Everything below concerns anxiolytic. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2025-11-22. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
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.
Selank is a synthetic heptapeptide developed in Russia during the 1990s. Researchers at the Institute of Molecular Genetics of the Russian Academy of Sciences designed it as a stabilized analog of tuftsin, a naturally occurring immunomodulatory tetrapeptide. The compound has been studied primarily for its reported anxiolytic and nootropic effects. It remains largely unknown in Western pharmacology and is not approved as a medicine by major regulators such as the FDA or the EMA.
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.
| Property | Value | Notes |
|---|---|---|
| Common route | Intranasal | Also injected in some animal work |
| Solubility class | Freely soluble in water | Solid form is hygroscopic |
| Typical storage | About -20 degrees Celsius | Keep desiccated and dark |
| Purity method | Reverse-phase HPLC | Reported as area percent |
| Confirmatory method | Mass spectrometry | Verifies expected molecular mass |
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.
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.
Characterization of Selank in a laboratory setting relies on standard peptide methods. Reverse-phase high-performance liquid chromatography separates the target from related impurities and provides a purity figure, commonly reported as 95 percent or higher. Mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, confirms the molecular mass and helps detect truncation or modification. Amino acid analysis can verify composition when a sequence-level check is needed. These techniques together establish identity and purity for a given lot.
Lyophilized Selank, the dry powder form, is generally stored frozen at minus 20 degrees Celsius or colder for long-term keeping. The solid is hygroscopic and should stay sealed, dry, and protected from light. Once dissolved, the peptide is less stable and is usually held refrigerated at 2 to 8 degrees Celsius for short periods. Repeated freezing and thawing is avoided because it can promote aggregation and loss of activity. Buffers and pH choice also affect how long a solution remains usable.
Solubility behavior is a practical concern for handling. Selank dissolves readily in water and in common aqueous buffers, which simplifies preparation of working solutions. The choice of solvent, ionic strength, and pH can influence aggregation over time, particularly at higher concentrations. Aqueous solutions are typically sterile-filtered before use. Because stability depends on several variables, storage and handling notes should be treated as general guidance rather than fixed rules, and specific values are best confirmed against a certificate of analysis for each batch.
It is localized in the cytosol, but in response to high glucose it becomes glycosylated by OGT and/or phosphorylated by ERK, which causes translocation to the nucleus. In the nucleus β2 heterodimerizes with E47, binds to the E1 element of the insulin promoter and recruits co-activator p300 which acetylates β2. It is able to interact with other transcription factors as well in activation of the insulin gene. MafA is degraded by proteasomes upon low blood glucose levels. Increased levels of glucose make an unknown protein glycosylated. This protein works as a transcription factor for MafA in an unknown manner and MafA is transported out of the cell. MafA is then translocated back into the nucleus where it binds the C1 element of the insulin promoter. These transcription factors work synergistically and in a complex arrangement. Increased blood glucose can after a while destroy the binding capacities of these proteins, and therefore reduce the amount of insulin secreted, causing diabetes. The decreased binding activities can be mediated by glucose induced oxidative stress and antioxidants are said to prevent the decreased insulin secretion in glucotoxic pancreatic β cells. Stress signalling molecules and reactive oxygen species inhibits the insulin gene by interfering with the cofactors binding the transcription factors and the transcription factors itself. Several regulatory sequences in the promoter region of the human insulin gene bind to transcription factors.
Bayer's original trade name of heroin is typically used in non-medical settings. It is used as a recreational drug for the euphoria it induces. Anthropologist Michael Agar once described heroin as "the perfect whatever drug." Tolerance develops quickly, and increased doses are needed in order to achieve the same effects. Its popularity with recreational drug users, compared to morphine, reportedly stems from its perceived different effects. Short-term addiction studies by the same researchers demonstrated that tolerance to heroin and morphine developed at a similar rate. When compared to the opioids hydromorphone, fentanyl, oxycodone, and pethidine (meperidine), former addicts showed a strong preference for heroin and morphine, suggesting that heroin and morphine are particularly susceptible to misuse and causing dependence. Morphine and heroin were also much more likely to produce euphoria and other positive subjective effects when compared to these other opioids. Heroin came into widespread use in South Africa in 2009 but the epidemic of heroin addiction has escalated since 2013 as prices have fallen rapidly in recent years. Heroin is primarily used by unemployed young men. Heroin generates intense feelings of euphoria, deep contentment, and relaxation. It also reduces appetite. Effects may last two to four hours. The drug can be inhaled after being warmed in a glass pipe but can be also smoked with cannabis in the form of a joint. It is primarily injected intravenously.
== Growth and morphology == Rhizopus oryzae grows quickly in optimal temperatures, at 1.6 mm per hour (nearly 0.5 μm per second - enough to be able to directly visualize hyphal elongation in real-time under the microscope). R. oryzae can grow in temperature of 7 °C to 44 °C and the optimum growth temperature is 37 °C. There is very poor growth from 10 °C to 15 °C and negligible growth at 45 °C. There is substantial growth in media containing 1% NaCl, very poor growth at 3% NaCl, and none at 5% NaCl. R. oryzae favors slightly acidic media. Good growth is observed at a pH of 6.8; in the range of 7.7-8.1, there is very poor growth. Most amino acids—with the exception of L-valine—promote R. oryzae growth, with L-tryptophan and L-tyrosine being the most effective. It also grows well on mineral nitrogen sources, except nitrate, and can utilize urea. Rhizopus oryzae has variable sporangiosphores. They can be straight or curved, swollen or branched, and the walls can be smooth or slightly rough. The colour of sporangiosphores range from pale brown to brown. Sporangiosphores grow between 210-2500 μm in length and 5-18 μm in diameter. The sporangia in R. oryzae are globose or subglobose, wall spinous and black when mature, 60-180 μm in diameter. They can be distinguishable from Rhizopus stolonifer as they have smaller sporangia and spores. The optimal conditions for sporangium production are temperatures between 30 °C to 35 °C and low water levels.
the carboxylation of glutamate allows for better binding of calcium cations, Hydroxyproline, generated by hydroxylation of proline, is a major component of the connective tissue collagen. Hypusine in the translation initiation factor EIF5A, contains a modification of lysine. Some non-proteinogenic amino acids are not found in proteins. Examples include 2-aminoisobutyric acid and the neurotransmitter gamma-aminobutyric acid. Non-proteinogenic amino acids often occur as intermediates in the metabolic pathways for standard amino acids – for example, ornithine and citrulline occur in the urea cycle, part of amino acid catabolism (see below). A rare exception to the dominance of α-amino acids in biology is the β-amino acid beta alanine (3-aminopropanoic acid), which is used in plants and microorganisms in the synthesis of pantothenic acid (vitamin B5), a component of coenzyme A.
Enthesitis, wherein there is inflammation of the entheses, the sites where tendons or ligaments insert into the bone. It is associated with HLA B27 arthropathies such as ankylosing spondylitis, psoriatic arthritis, and reactive arthritis. Apophysitis, inflammation of the bony attachment, generally associated with overuse among growing children.
Sources: en.wikipedia.org
=== Partial-thickness engineered oral mucosa === Cell culture techniques make it possible to produce epithelial sheets for the replacement of damaged oral mucosa. Partial-thickness tissue engineering uses one type of cell layer, this can be in monolayers or multilayers. Monolayer epithelial sheets suffice for the study of the basic biology of oral mucosa, for example its responses to stimuli such as mechanical stress, growth factor addition and radiation damage. Oral mucosa, however, is a complex multilayer structure with proliferating and differentiating cells and monolayer epithelial sheets have been shown to be fragile, difficult to handle and likely to contract without a supporting extracellular matrix. Monolayer epithelial sheets can be used to manufacture multilayer cultures. These multilayer epithelial sheets show signs of differentiation such as the formation of a basement membrane and keratinization. Fibroblasts are the most common cells in extracellular matrix and are important for epithelial morphogenesis. If fibroblasts are absent from the matrix, the epithelium stops proliferating but continues to differentiate. The structures obtained by partial-thickness oral mucosa engineering form the basis for full-thickness oral mucosa engineering.
=== Scarless wound healing === Scarless wound healing is a concept based on the healing or repair of the skin (or other tissue/organs) after injury with the aim of healing with subjectively and relatively less scar tissue than normally expected. Scarless healing is sometimes mixed up with the concept of scar free healing, which is wound healing that results in absolutely no scar (free of scarring) may occur naturally at some locations of the human body and research in 2025 has decoded molecular players that drive that scarless healing. However, they are different concepts. The opposite of scarless wound healing is scarification (wound healing to scar more). Historically, certain cultures consider scarification attractive; however, this is generally not the case in the modern western society, in which many patients are turning to plastic surgery clinics with unrealistic expectations. Depending on scar type, treatment may be invasive (intralesional steroid injections, surgery) and/or conservative (compression therapy, topical silicone gel, brachytherapy, photodynamic therapy). Clinical judgment is necessary to successfully balance the potential benefits of the various treatments available against the likelihood of a poor response and possible complications resulting from these treatments. Many of these treatments may only have a placebo effect, and the evidence base for the use of many current treatments is poor.
Plastic casings are not eaten. They also can be flat or shirred. Generally, smoke and water cannot pass through the casing, so plastic is used for non-smoked products where high yields are expected. The inner surface can be laminated or co-extruded with a polymer with an affinity for meat protein causing the meat to stick to the film, resulting in some loss when the casing is peeled, but higher overall yield due to better moisture control. Plastic casings are generally made from polymers such as polyamide, polypropylene, or polyethylene. Polyamide (Nylon) plastic casings are the most commonly used in production of cooked sausages and hams such as luncheon meat and bologna. Polyamide casings come in two main varieties: Oriented and non-oriented. The oriented polyamide are shrinkable casings and will shrink during the cooking process thereby reducing the water loss. Non-oriented polyamide casings remain the same diameter during the cooking process and thereby allow for expansion of the meat during cooking. The use of polyamide casings has expanded recently with the advent of various varieties and structures of casings such as multilayer casings.
An anxiolytic (; also antipanic or anti-anxiety agent) is a medication or other intervention that reduces anxiety. This effect is in contrast to anxiogenic agents which increase anxiety. Anxiolytic medications are used for the treatment of anxiety disorders and their related psychological and physical symptoms.
Sources: en.wikipedia.org
Most published work uses intranasal application, either as drops or as a nasal spray. Injection routes appear in a smaller set of animal experiments. Oral use is uncommon in the literature because peptide breakdown and poor absorption limit this route.
Reported human trials are few, brief and originate mainly from one country. They describe effects on anxiety-related measures, but sample sizes are small and reporting is limited. The results are widely regarded as preliminary rather than confirmed.
Reverse-phase liquid chromatography is used to assess purity and separation of related impurities. Mass spectrometry confirms that the observed molecular mass matches the expected peptide. A certificate of analysis from the supplier is the usual document of record.
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.