A practical reference on peptidase: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-11-29. Anything still debated is marked as such rather than presented as settled.
The primary structure of Selank is Thr-Lys-Pro-Arg-Pro-Gly-Pro, corresponding to the molecular formula C33H57N11O9 and a monoisotopic mass of roughly 751.9 daltons. The N-terminal threonine and the arginine residue in the fourth position are shared with tuftsin, which carries the sequence Thr-Lys-Pro-Arg. The three additional residues at the C-terminus, Pro-Gly-Pro, extend the chain and are associated with greater resistance to enzymatic degradation. This extension also separates Selank from the shorter parent peptide.
Naming conventions place Selank in the same research family as Semax, another Russian-developed peptide investigated for cognitive effects. The two compounds share a lineage but differ in sequence and in the biological systems proposed as their targets. Semax descends from ACTH fragments, whereas Selank descends from tuftsin. Publications sometimes identify Selank by its full peptide sequence or by laboratory codes rather than one uniform trade name. Because replication outside Russia is limited, reports on its properties are best read alongside the study design and the purity of the material tested.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic heptapeptide | Stabilized analog of tuftsin |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Single-letter form: TKPRPGP |
| Molecular formula | C33H57N11O9 | Monoisotopic mass about 751.9 Da |
| Appearance | White to off-white powder | Typically supplied as lyophilized solid |
| Solubility | Freely soluble in water | Also soluble in common polar solvents |
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 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.
In the United Kingdom, a new excise duty on vaping products (Vaping Products Duty) is scheduled to take effect from 1 October 2026, with registrations opening on 1 April 2026, following consultation. The government said it would implement a flat-rate structure of £2.20 per 10 mL of vaping liquid, alongside a one-off increase in tobacco duty to preserve the financial incentive to switch from smoking to vaping.
"Chordate". The Encyclopedia of Life. Chordate on GlobalTwitcher.com Chordate node at Tree Of Life Archived 24 February 2007 at the Wayback Machine Chordate node at NCBI Taxonomy Archived 28 April 2021 at the Wayback Machine
== 2023 UFC Honors awards == Starting in 2019, the UFC created year-end awards with "UFC Honors President's Choice Awards" for categories "Performance of the Year" and "Fight of the Year" being chosen by UFC CEO Dana White. The other "UFC Honors Fan Choice Awards" are for categories "Knockout of the Year", "Submission of the Year", "Event of the Year", "Comeback of the Year" and, from 2020, "Debut of the Year" in which fans are able to vote for the winner on social media. Winners receive a trophy commemorating their achievement along with a set of tires from sponsor Toyo Tires.
Stanley Airport is used by internal flights and provides connections to British bases in Antarctica. Flights to Argentina ended after the 1982 conflict. A weekly flight to Punta Arenas in Chile commenced in 1993, which now operates out of RAF Mount Pleasant. Scheduled passenger flights between the Mount Pleasant airfield and the UK are also operated twice a week by a civilian airline contractor on behalf of the Royal Air Force. Stanley was occupied by Argentine troops for about 10 weeks during the Falklands War in 1982. The Argentinians renamed the town Puerto Argentino, and although Spanish names for places in the Falklands were historically accepted as alternatives, this one is considered to be extremely offensive by many islanders. Stanley suffered considerable damage during the war, from both the Argentine occupation and the British naval shelling of the town, which killed three civilians. After the British secured the high ground around the town the Argentines surrendered with no fighting in the town itself. The beaches and land around it were heavily mined and some areas remain marked minefields. Since the Falklands War, Stanley has benefited from the growth of the fishing and tourism industries in the Islands. Stanley itself has developed greatly in that time, with the building of a large amount of residential housing, particularly to the east of the town centre. Stanley is now more than a third bigger than it was in 1982.
Supplementation can also contribute to the managing the symptomatic effects of hyperandrogenism. In a meta-analysis, high-dose vitamin D supplements given to women with vitamin D deficiency due to PMOS improved glucose levels, insulin sensitivity, and cholesterol levels, as well as lowering testosterone, sex hormone-binding globulin, and the free androgen index, all of which are associated with hyperandrogenism. Vitamin D supplementation in women with vitamin D deficiency but without PMOS did not show the same results.
Sources: en.wikipedia.org
Histoire et dictionnaire de Paris [History and dictionary of Paris] (in French). Paris: Éditions Robert-Laffont. Auguste, Jal (1872). Dictionnaire critique de biographie et d'histoire [Critical Dictionary of Biography and History] (in French). Paris: Éditions Plon. Piot, Eugène (1873). État civil de quelques artistes français [Marital status of some French artists] (in French). Paris: Librairie Pagnerre.
==== Glutathione ==== Glutathione or its homologues, e.g. homoglutathione in Fabaceae; hydroxymethylglutathione in Poaceae are the major water-soluble non-protein thiol compounds present in plant tissue and account for 1-2% of the total sulfur. The content of glutathione in plant tissue ranges from 0.1 – 3 mM. Cysteine is the precursor to glutathione (and its homologues). First, γ-glutamylcysteine is synthesized from cysteine and glutamate catalyzed by gamma-glutamylcysteine synthetase. Second, glutathione is synthesized from γ-glutamylcysteine and glycine (in glutathione homologues, β-alanine or serine) catalyzed by glutathione synthetase. Both steps of the synthesis of glutathione are ATP-dependent. Glutathione is maintained in the reduced form by an NADPH-dependent glutathione reductase, and the ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG) generally exceeds a value of 7. In sulfur metabolism glutathione is reductant for the conversion of APS to sulfite. It is also the major transport form of reduced sulfur in plants. Roots likely largely depend for their reduced sulfur supply on shoot/root transfer of glutathione via the phloem, since the reduction of sulfur occurs predominantly in the chloroplast. Glutathione is also involved in the reduction and assimilation of selenite into selenocysteine.
It has since been elucidated that androgens like testosterone and dihydrotestosterone (DHT) function as trophic factors for the prostate gland, stimulating cell division and proliferation and producing tissue growth and glandular enlargement, which, in the context of prostate cancer, results in stimulation of tumors and a considerable acceleration of disease progression. As a result of these discoveries, androgen deprivation therapy (ADT), via a variety of modalities including surgical castration, high-dose estrogens, SAAs, GnRH analogues, NSAAs, and androgen biosynthesis inhibitors (e.g., abiraterone acetate), has become the mainstay of treatment for prostate cancer. Although ADT can shrink or stabilize prostate tumors and hence significantly slow the course of prostate cancer and prolong life, it is not generally curative. While effective in slowing the progression of the disease initially, most advanced prostate cancer patients eventually become resistant to ADT and prostate cancer growth starts to accelerate again, in part due to progressive mutations in the androgen receptor (AR) that result in the transformation of drugs like bicalutamide from AR antagonists to agonists. A few observations form the basis of the reasoning behind combined androgen blockade (CAB), in which castration and an NSAA are combined. It has been found that very low levels of androgens, as in castration, are able to significantly stimulate growth of prostate cancer cells and accelerate disease progression.
== Inferior == The inferior tarsus (tarsus inferior; inferior tarsal plate) is smaller, is thin, is elliptical in form, and has a vertical diameter of about 5 mm (0.2 in). The free or ciliary margins of these plates are thick and straight.
Sources: en.wikipedia.org
=== Divergences with A&W (Great American Brand) === The Canadian menu diverges significantly from their international counterparts franchised through A Great American Brand. This divergence is due to the brand's separate management and ownership. The only Burger Family product available by name in U.S. locations is the Papa Burger. The Papa Burger differs significantly between Canada and the U.S. Notable products on the U.S. menu not available in Canada include deep-fried cheese curds and soft serve-based products such as sundaes.
Proto-oncogene tyrosine-protein kinase Fyn (p59-FYN, Slk, Syn, MGC45350, Gene ID 2534) is an enzyme that in humans is encoded by the FYN gene. Fyn is a 59-kDa member of the Src family of kinases typically associated with T-cell and neuronal signaling in development and normal cell physiology. Disruptions in these signaling pathways often have implications in the formation of a variety of cancers. By definition as a proto-oncogene, Fyn codes for proteins that help regulate cell growth. Changes in its DNA sequence transform it into an oncogene that leads to the formation of a different protein with implications for normal cell regulation. Fyn is a member of the protein-tyrosine kinase oncogene family. It encodes a membrane-associated tyrosine kinase that has been implicated in the control of cell growth. The protein associates with the p85 subunit of phosphatidylinositol 3-kinase and interacts with the fyn-binding protein. Alternatively spliced transcript variants encoding distinct isoforms exist.
Alza Corporation was an American pharmaceutical and medical systems company. Founded in 1968 by Dr. Alejandro Zaffaroni; the company's name is a portmanteau of his name. Alza was a major pioneer in the field of drug delivery systems, bringing over 20 prescription pharmaceutical products to market, and employing about 10,000 people during 20 years. In 2001, Alza was acquired by Johnson & Johnson via a stock-for-stock transaction worth US$10.5 billion. The company owns the patents on the following delivery platforms: Alzamer Depot D-Trans DUROS implant E-Trans electrotransport OROS (Osmotic Release Oral System) Macroflux transdermal system Stealth liposomal
Sources: en.wikipedia.org
Selank is a synthetic heptapeptide designed as a stabilized analog of the natural tetrapeptide tuftsin. It has been investigated mainly for anxiolytic and cognitive effects. It is not an approved pharmaceutical in most countries.
It was developed in Russia, at the Institute of Molecular Genetics of the Russian Academy of Sciences, during the 1990s. Most published research originates from Russian institutions. Independent international replication remains limited.
Tuftsin is a natural tetrapeptide with the sequence Thr-Lys-Pro-Arg that participates in immune signaling. Selank extends that sequence with Pro-Gly-Pro at the C-terminus. The added residues are linked to greater resistance to enzymatic breakdown.
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.