A practical reference on Intranasal route: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-07-07. Anything still debated is marked as such rather than presented as settled.
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. 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.
Proposed mechanisms center on modulation of the GABA system, but no single molecular target has been confirmed. Rodent studies report changes in GABA-A receptor expression and in the turnover of serotonin, dopamine, and norepinephrine in several brain regions. Increases in brain-derived neurotrophic factor and its receptor have also been described after repeated administration. These findings come largely from animal models, and the degree to which they describe human neurochemistry remains an open question. The mechanism is best characterized as multi-system and not fully resolved.
Pharmacokinetic data are limited. Like most short peptides, Selank is vulnerable to plasma and tissue peptidases, and its measured half-life in circulation is short, on a minutes scale. The Pro-Gly-Pro tail slows this degradation but does not eliminate it. Intranasal administration is the route described in most reports, with absorption through the nasal mucosa and a hypothesized path into the central nervous system that avoids the blood-brain barrier. Direct measurements of human brain exposure are unavailable, so distribution claims rest on inference from animal work.
| 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 |
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.
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.
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.
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.
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.
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.
==== European Union ==== In November 2007, the European Commission requested the European Medicines Agency (EMA) to review the safety and effectiveness of dextropropoxyphene based medicines and on 25 June 2009 the EMA recommended a gradual withdrawal throughout the European Union. The EMA's conclusion was based on evidence that dextropropoxyphene-containing medicines were weak painkillers, the combination of dextropropoxyphene and paracetamol was no more effective than paracetamol on its own, and the difference between the dose needed for treatment and a harmful dose (the "therapeutic index") was too small.
After Protestantism, individuals professing no religion are also a significant group, having exceeded 8% of the population according to the 2010 census. The cities of Boa Vista, Salvador, and Porto Velho have the greatest proportion of Irreligious residents in Brazil. Teresina, Fortaleza, and Florianópolis were the most Roman Catholic in the country. Greater Rio de Janeiro, not including the city proper, is the most irreligious and least Roman Catholic Brazilian periphery, while Greater Porto Alegre and Greater Fortaleza are on the opposite sides of the lists, respectively. In October 2009, the Brazilian Senate approved, and enacted by the President of Brazil in February 2010, an agreement with the Vatican, in which the Legal Statute of the Catholic Church in Brazil is recognized.
Hindu-Arabic numerals were not originally designed to indicate their numeric value through the number of angles they contain. There are no historical records of this, and the myth is difficult to reconcile with digits past 3 or 4. The Greek philosopher Pythagoras was not the first to discover what is now called the Pythagorean theorem, as it was known and used by the Babylonians and Indians centuries before him. Pythagoras may have been the first to introduce it to the Greeks, but the first record of it being mathematically proven as a theorem is in Euclid's Elements which was published some 200 years after Pythagoras. There is no evidence that the ancient Greeks deliberately designed the Parthenon to match the golden ratio. The Parthenon was completed in 438 BCE, more than a century before the first recorded mention of the ratio by Euclid. Similarly, Leonardo da Vinci's Vitruvian Man makes no mention of the golden ratio in its text, although it describes many other proportions. The repeating decimal written as 0.999... represents exactly the same quantity as 1. The p-value is not the probability that the null hypothesis is true, or the probability that the alternative hypothesis is false; it is the probability of obtaining results at least as extreme as the results actually observed under the assumption that the null hypothesis was correct, which can indicate the incompatibility of results with the specific statistical model assumed in the null hypothesis. This misconception, and similar ones like it, contributes to the common misuse of p-values in education and research.
Sources: en.wikipedia.org
==== Return to government in 2023 ==== Lad was re-elected from Kalaghatgi in the 2023 Karnataka Assembly election and was inducted into Siddaramaiah's cabinet on 27 May 2023 as Minister for Labour. He was also appointed minister in charge of Dharwad district in June 2023.
President Donald Trump has stated the goals of the war were to destroy Iran's ballistic missiles, eliminate their navy, prevent them from acquiring nuclear weapons, and to stop Iranian proxies from holding power. Trump asserted that Iran's ballistic missile program could endanger US allies "throughout the world", including Europe and American mainland. Pete Hegseth said that Iran would be capable of nuclear blackmail with their ballistic missiles if the US did not attack it. However, a Defense Intelligence Agency assessment determined that Iran would not be capable of building intercontinental ballistic missiles until 2035. Secretary of State Marco Rubio warned that Iran posed an "imminent threat" to US bases in the event of Israeli strikes on Iran, thereby portraying the war as a preemptive one. Mike Johnson, the Speaker of the United States House of Representatives and Rubio said that Israel was going to attack Iran, after which Iran's retaliations against US bases would have brought them into war anyway. Senator Mark Warner of the Senate Intelligence Committee who was briefed by Rubio before the war began said that there was no evidence that Iran was going to launch a pre-emptive strike against the US, and that the war was ultimately decided upon by Israel. Trump rejected these claims, stating that "I might have forced their hands.
=== Approval ratings === In a survey conducted by Ipespe/Febraban and released in February 2023, Lula's third government was rated as good or excellent by 40% of Brazilians, regular by 27%, and bad or terrible by 28%, while 5% did not respond. In the following month, between the 2nd and 6th, Ipec conducted an analysis that was released on the 19th; in it, 41% of Brazilians rated the government as "good or excellent", 30% considered the administration "regular", and 24% thought it was "bad or terrible"; 5% did not know or preferred not to respond. In this way, Lula began his third term with higher approval than his predecessor, Jair Bolsonaro, who in March 2019 was considered "good or excellent" by 34%. Regarding confidence in Lula, 53% of the population said they trusted him, while 43% stated that they did not trust him and 4% preferred not to express an opinion. Finally, the survey found that the president's way of governing had the approval of 57% of Brazilians. On 29 and 30 March, Datafolha interviewed 2,028 people in 126 municipalities, and the Lula government was rated as excellent or good by 38%, regular by 30%, and bad or terrible by 29% of respondents. On 23 May, according to a new survey, 54% of respondents approved of the government, while 39% of respondents disapproved of the government. In June 2023, according to a new Ipec survey, the Lula government had the approval of 37% of the population, while 32% considered it regular, 28% disapproved of it, and 3% did not know how to answer.
==== Effects ==== In contrast to amphetamines like (–)-cathinone, but similarly to mescaline, DOM has shown no stimulant-like or reinforcing effects in rhesus monkeys. Conversely however, DOC has shown reinforcing effects, including conditioned place preference (CPP) and self-administration, in rodents similarly to methamphetamine. This is analogous to other findings in which various 2C and NBOMe drugs have been found to produce brain dopaminergic elevations and reinforcing effects in rodents.
Sources: en.wikipedia.org
=== Chemical toxicity === The chemical toxicity of depleted uranium is identical to that of natural uranium and about a million times greater in vivo than DU's radiological hazard, with the kidney considered to be the main target organ. Health effects of DU are determined by factors such as the extent of exposure and whether it was internal or external. Three main pathways exist by which internalization of uranium may occur: inhalation, ingestion, and embedded fragments or shrapnel contamination. Properties such as phase (e.g. particulate or gaseous), oxidation state (e.g. metallic or ceramic), and the solubility of uranium and its compounds influence their absorption, distribution, translocation, elimination and the resulting toxicity. For example, metallic uranium is less toxic compared to hexavalent uranium(VI) uranyl compounds such as uranium trioxide (UO3).
== Adverse effects == In individuals already taking sulphonylureas, use of DPP-4-class medications concurrently increases their risk for low blood sugar events relative to those on sulphonylureas alone. Adverse effects include nasopharyngitis, headache, nausea, heart failure, hypersensitivity, and skin reactions. In late August 2015, the US FDA issued a warning that drugs like sitagliptin, saxagliptin, linagliptin, alogliptin, and other DPP-4 inhibitors could cause joint pain that can be severe and disabling. However, studies assessing risk of rheumatoid arthritis among DPP-4 inhibitor users have been inconclusive. A 2014 review found that the use of saxagliptin and alogliptin increased individuals' risk of developing heart failure, leading the FDA to add warnings to the labels of these drugs in 2016. A 2018 meta-analysis indicated that the use of DPP-4 inhibitors was associated with a 58% increased risk of developing acute pancreatitis compared to placebo or no treatment. Additionally, a 2018 observational study suggested an elevated risk of developing inflammatory bowel disease, specifically ulcerative colitis, which peaked after three to four years of use and decreased after more than four years. Finally, a 2020 Cochrane systematic review found insufficient evidence to suggest that metformin monotherapy reduced all-cause mortality, serious adverse events, cardiovascular mortality, non-fatal myocardial infarction, non-fatal stroke, or end-stage renal disease when compared to DPP-4 inhibitors for the treatment of type 2 diabetes.
== Macromolecules in nature == Proteins are polymers of amino acids joined by peptide bonds. DNA and RNA are polymers of nucleotides joined by phosphodiester bonds. These nucleotides consist of a phosphate group, a sugar (ribose in the case of RNA, deoxyribose in the case of DNA), and a nucleotide base (either adenine, guanine, thymine, uracil, or cytosine, where thymine occurs only in DNA and uracil only in RNA). Polysaccharides (such as starch, cellulose, and chitin) are polymers of monosaccharides joined by glycosidic bonds. Some lipids (organic nonpolar molecules) are macromolecules, with a variety of different structures.
The West Bengal Police has jurisdiction concurrent with the twenty-two revenue districts of the State (excluding the metropolitan city of Kolkata) which comprises one of the two general police districts of West Bengal under the Police Act 1861. The other general police district consists of the major portions of the metropolitan area of Kolkata, and has a separate police force (Kolkata Police Commissionerate) constituted and administered under the Calcutta Police Act 1866 & Calcutta (Suburban Police) Act 1866. This arrangement, unique in India, was conceived during colonial times when Calcutta was the capital of British India. The city police have been kept independent of the state police force.
== Education == Fischbach earned his A.B. in Biochemical Sciences from Harvard College in 2003. During that time (2000–2003), he worked in Jeffrey Settleman's lab at the Massachusetts General Hospital Cancer Center on the biochemistry of oncogenic mutants of the small GTPase Ras. In 2007, he earned his Ph.D. in Chemistry and Chemical Biology from Harvard University, working in Christopher T. Walsh's laboratory at Harvard Medical School on iron acquisition in bacterial pathogens and the biochemistry of natural product biosynthesis.
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.
Reports describe effects on GABA-A receptor expression, monoamine turnover, and neurotrophic factor levels. These are proposed mechanisms drawn mainly from animal models. No single molecular target has been established.