pineal peptides raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2025-10-01. Anything still debated is marked as such rather than presented as settled.
The four residues give epitalon a molecular formula of C14H22N4O9 and a molecular weight near 390.35 daltons. The presence of two acidic residues, glutamate and aspartate, makes the free peptide strongly acidic, while the alanine and glycine ends provide neutral, nonpolar character. This combination produces a molecule with substantial water solubility. Because there are no cysteine, methionine, or tryptophan residues, the peptide lacks the most common oxidation-sensitive side chains, which simplifies handling compared with many longer peptides.
The proposed relationship between epitalon and pineal function is a central part of its background. Khavinson's group reported that short peptides corresponding to regions of larger pineal proteins could influence gene expression in cells. Epitalon was framed as a synthetic analogue of an active fragment rather than a direct isolation product. Whether the tetrapeptide reproduces the effects of the parent extract is an open question, because comparative studies are limited and the parent extract itself is not a single defined substance.
Epitalon is a synthetic tetrapeptide with the residue sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its monoisotopic mass is approximately 390.35 daltons, and it is usually supplied as a lyophilised trifluoroacetate or acetate salt. The compound was derived from a pineal gland extract called epithalamin, a heterogeneous preparation investigated in the former Soviet Union. Researchers associated with the Saint Petersburg Institute of Bioregulation and Gerontology described the tetrapeptide as a constituent fragment of that extract. Commercial material is offered as a laboratory reagent rather than as a finished pharmaceutical product.
Literature searches for this compound must account for several spelling variants. Indexing databases contain epitalon, epithalon, epithalone, and AEDG, and relevant records are scattered across Russian-language and English-language journals that do not consistently cross-cite. Early publications describe the parent extract as a mixture of many peptides, whereas later work addresses the single synthetic tetrapeptide. That shift in nomenclature complicates comparison between studies, because extract data and tetrapeptide data are sometimes cited interchangeably. A search strategy omitting the alternate spellings will return an incomplete set of references.
| Property | Value | Notes |
|---|---|---|
| Amino acid sequence | Ala-Glu-Asp-Gly | Tetrapeptide, often abbreviated AEDG |
| Molecular formula | C14H22N4O9 | Free peptide, unmodified termini |
| Molecular weight | ~390.35 Da | Calculated for the free acid form |
| Appearance | White to off-white powder | Typical lyophilized product form |
| Solubility class | Freely soluble in water | Two acidic residues dominate ionic character |
Epitalon is a synthetic tetrapeptide whose sequence is alanine-glutamate-aspartate-glycine, written in single-letter code as AEDG. The four residues are joined by three peptide bonds, giving a linear backbone with no branching and no disulfide bridges. Its calculated molecular mass for the free form is approximately 390.3 daltons, a figure that rises when the compound is supplied as an acetate or trifluoroacetate salt. Because the chain is short, the molecule is defined entirely by its residue order rather than by any folded three-dimensional structure.
The compound is described in the literature as a derivative of epithalamin, a preparation obtained from bovine pineal tissue. Work on this peptide family was carried out mainly by a research group in Saint Petersburg beginning in the 1980s, and the substance was later registered for clinical use in Russia under the name Epitalon. Outside that region it is generally treated as a research chemical rather than an approved medicine. Statements about its biological activity rest on a relatively small number of studies, and independent replication remains limited.
In its supplied form epitalon is a white to off-white powder, usually lyophilized and often hygroscopic. It dissolves readily in water and in aqueous buffers, and it is commonly handled as the acetate or trifluoroacetate salt to improve stability during purification and drying. The amide backbone is labile in aqueous media, so solutions are less durable than the dry solid. Handling notes in the chemical literature therefore emphasize keeping the powder dry, cool and shielded from light until it is dissolved.
Epitalon is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, abbreviated AEDG. Its molecular formula is C14H22N4O9 and its calculated monoisotopic mass is approximately 390.35 daltons. The compound does not occur naturally as a free peptide; it is produced by solid-phase peptide synthesis. Because it contains two acidic residues and no basic residues, the neutral form carries a net negative charge at physiological pH. This charge profile influences how the peptide behaves in solution and during chromatographic analysis.
Laboratory-grade epitalon is typically supplied as a lyophilized powder. Purity is commonly assessed with reverse-phase high-performance liquid chromatography, often paired with mass spectrometry to confirm molecular identity. Amino acid analysis and peptide mapping can provide additional confirmation of sequence. Certificates of analysis for research materials frequently report purity above 95 percent, although the methods behind such figures vary between suppliers. The absence of a pharmacopeial monograph means that no single standardized assay defines the compound, so reported results depend on the analytical protocol chosen.
The compound is generally presented as a synthetic fragment of epithalamin, a pineal gland extract investigated in the former Soviet Union from the 1970s onward. Vladimir Khavinson and colleagues in Saint Petersburg developed short peptides modelled on such extracts, and epitalon became the most widely cited of those sequences. Most primary reports appeared in Russian-language journals or in proceedings with limited international circulation. Independent replication in laboratories outside that network remains sparse, and much repeated secondary material traces back to a small number of originating groups.
Laboratory work has examined effects on telomerase activity in cultured cells, on melatonin rhythms in animals, and on markers of oxidative stress. Some experiments report measurable changes while others show none, and the reported findings rest largely on small studies. The absence of large independent trials means the generality of these results is unresolved rather than settled. Review articles occasionally apply the label geroprotector, a term that reflects a research hypothesis about ageing rather than an established clinical finding.
=== Other symptoms === Breathing difficulties can occur, resulting from neuromyotonic activity of the laryngeal muscles. Laryngeal spasm possibly resulting from neuromyotonia has been described previously, and this highlights that, in patients with unexplained laryngospasm, neuromytonia should be added to the list of differential diagnoses. Studies have shown subtly decreased metabolism on positron emission tomography (PET) and single photon emission computed tomography (SPECT) in the left inferior frontal and left temporal lobes. and or basal ganglia hypermetabolism. Ancillary laboratory tests including MRI and brain biopsy have confirmed temporal lobe involvement. Cranial MRI shows increased signal in the hippocampus. Cerebral spinal fluid (CSF) shows normal protein, glucose, white blood cell, and immunoglobulin G (IgG) levels, but there are weak oligoclonal bands, which are absent in the blood serum. Marked changes in circadian serum levels of neurohormones and increased levels of peripheral neurotransmitters were also observed. The absence of morphological alterations of the brain pathology, the suggestion of diffusion of IgG into the thalamus and striatum, more marked than in the cortex (consistent with effects on the thalamolimbic system) the oligoclonal bands in the CSF and the amelioration after PE all strongly support an antibody-mediated basis for the condition. Raised CSF IgG concentrations and oligoclonal bands have been reported in patients with psychosis.
The primary structure of a biological polymer to a large extent determines the three-dimensional shape (tertiary structure). Protein sequence can be used to predict local features, such as segments of secondary structure, or trans-membrane regions. However, the complexity of protein folding currently prohibits predicting the tertiary structure of a protein from its sequence alone. Knowing the structure of a similar homologous sequence (for example a member of the same protein family) allows highly accurate prediction of the tertiary structure by homology modeling. If the full-length protein sequence is available, it is possible to estimate its general biophysical properties, such as its isoelectric point.
Tuftsin is a tetrapeptide (Thr-Lys-Pro-Arg, TKPR) located in the Fc-domain of the heavy chain of immunoglobulin G (residues 289-292). It has an immunostimulatory effect. It is named for Tufts University where it was first discovered in 1983.
Sources: en.wikipedia.org
The development of a germanium-wire based anode that more than doubles the capacity of lithium-ion batteries was reported in 2014. In the same year, Lee et al. reported that defect-free crystals of graphene large enough to have electronic uses could be grown on, and removed from, a germanium substrate. Arsenic and antimony are not semiconductors in their standard states. Both form type III-V semiconductors (such as GaAs, AlSb or GaInAsSb) in which the average number of valence electrons per atom is the same as that of Group 14 elements, but they have direct band gaps. These compounds are preferred for optical applications. Antimony nanocrystals may enable lithium-ion batteries to be replaced by more powerful sodium ion batteries. Tellurium, which is a semiconductor in its standard state, is used mainly as a component in type II/VI semiconducting-chalcogenides; these have applications in electro-optics and electronics. Cadmium telluride (CdTe) is used in solar modules for its high conversion efficiency, low manufacturing costs, and large band gap of 1.44 eV, letting it absorb a wide range of wavelengths. Bismuth telluride (Bi2Te3), alloyed with selenium and antimony, is a component of thermoelectric devices used for refrigeration or portable power generation. Five metalloids – boron, silicon, germanium, arsenic, and antimony – can be found in cell phones (along with at least 39 other metals and nonmetals). Tellurium is expected to find such use. Of the less often recognised metalloids, phosphorus, gallium (in particular) and selenium have semiconductor applications.
== Causes of elevated IGF1 levels == Medical conditions: acromegaly (especially when GH is also high) delayed puberty pregnancy hyperthyroidism some rare tumors, such as carcinoids, secreting IGF1 Diet: High-protein diet consumption of dairy products (except for cheese) consumption of fish IGF1 assay problems Calorie restriction has been found to have no effect on IGF1 levels.
Circumcision is a surgical procedure that removes the foreskin from the human penis. In the procedure's most common form, the foreskin is extended with forceps, then a circumcision device may be placed, after which the foreskin is excised. Topical or locally injected anesthesia is generally used to reduce pain and physiologic stress. Circumcision is undertaken for religious, cultural, social, and medical reasons. It may be medically necessary in cases of phimosis, chronic urinary tract infections (UTIs), and other pathologies of the penis that do not resolve with other treatments. The procedure is contraindicated in cases of certain genital structure abnormalities or poor general health. The procedure is associated with reduced rates of urinary tract infections and sexually transmitted infections including incidence of cancer-causing forms of human papillomavirus (HPV), and is known to reduce HIV transmission among heterosexual men in high-risk populations by up to 60%; its prophylactic efficacy against HIV transmission in the developed world or among men who have sex with men is debated. Neonatal circumcision decreases the risk of penile cancer. Complication rates increase significantly with age. Bleeding, infection, and the removal of either too much or too little foreskin are the most common acute complications, while meatal stenosis is the most common long-term. There are various cultural, social, legal, and ethical views on circumcision. Major medical organizations hold differing views on circumcision's prophylactic efficacy in developed countries.
Sources: en.wikipedia.org
A protein called divalent metal transporter 1 (DMT1), which can transport several divalent metals across the plasma membrane, then transports iron across the enterocyte's cell membrane into the cell. If the iron is bound to heme it is instead transported across the apical membrane by heme carrier protein 1 (HCP1). These intestinal lining cells can then either store the iron as ferritin, which is accomplished by Fe2+ binding to apoferritin (in which case the iron will leave the body when the cell dies and is sloughed off into feces), or the cell can release it into the body via the only known iron exporter in mammals, ferroportin. Hephaestin, a ferroxidase that can oxidize Fe2+ to Fe3+ and is found mainly in the small intestine, helps ferroportin transfer iron across the basolateral end of the intestine cells. In contrast, ferroportin is post-translationally repressed by hepcidin, a 25-amino acid peptide hormone. The body regulates iron levels by regulating each of these steps. For instance, enterocytes synthesize more Dcytb, DMT1 and ferroportin in response to iron deficiency anemia. Iron absorption from diet is enhanced in the presence of vitamin C and diminished by excess calcium, zinc, or manganese. The human body's rate of iron absorption appears to respond to a variety of interdependent factors, including total iron stores, the extent to which the bone marrow is producing new red blood cells, the concentration of hemoglobin in the blood, and the oxygen content of the blood.
=== Foundation and early years === Medtronic was founded in 1949 in Minneapolis by Earl Bakken and his brother-in-law, Palmer Hermundslie, as a medical equipment repair shop. Bakken invented several medical technology devices that continue to be used around the world today. Through his repair business, Bakken came to know C. Walton Lillehei, a doctor of heart surgery at the University of Minnesota Medical School. The deficiencies of artificial pacemakers at the time became evident during a power outage over Halloween in 1957, which affected large sections of Minnesota and western Wisconsin. A pacemaker-dependent paediatric patient of Lillehei died because of the blackout. The next day, Lillehei spoke with Bakken about developing some form of battery-powered pacemaker. Bakken modified the design for a transistorized metronome and created the first battery-powered external pacemaker. It fit in a four-inch-square box that could be taped to a patient's chest, transmitted electrical signals to the heart through wires that passed through the patient's chest, and could be removed without surgery.
== Relationship to East and Southeast Asians == Genetic markers of immunoglobulin among the Sinhalese show high frequencies of afb1b3 which has its origins in the Yunnan and Guangxi provinces of southern China. It is also found at high frequencies among Odias, certain Nepali and Northeast Indian, southern Han Chinese, Southeast Asian and certain Austronesian populations of the Pacific Islands. At a lower frequency, ab3st is also found among the Sinhalese and is generally found at higher frequencies among northern Han Chinese, Tibetan, Mongolian, Korean and Japanese populations. The Transferrin TF*Dchi allele which is common among East Asian and Native American populations is also found among the Sinhalese. HumDN1*4 and HumDN1*5 are the predominant DNase I genes among the Sinhalese and are also the predominant genes among southern Chinese ethnic groups and the Tamang people of Nepal. A 1988 study conducted by N. Saha, showed the high GC*1F and low GC*1S frequencies among the Sinhalese are comparable to those of the Chinese, Japanese, Koreans, Thais, Malays, Vietnamese, Laotians and Tibetans. Hemoglobin E a variant of normal hemoglobin, which originated in and is prevalent among populations in Southeast Asia, is also common among the Sinhalese and can reach up to 40% in Sri Lanka.
Sources: en.wikipedia.org
Epitalon is a synthetic tetrapeptide composed of four amino acids: alanine, glutamate, aspartate, and glycine. It is written as Ala-Glu-Asp-Gly. The free peptide has a molecular weight of about 390 daltons and is normally supplied as a lyophilized powder.
No. Epitalon is chemically synthesized, not extracted. It was designed as a short synthetic fragment conceptually related to larger pineal peptides studied in the same research tradition, particularly the extract known as epithalamin. The two are distinct materials with different compositions.
The term bioregulator is used in this research tradition for short peptides proposed to influence gene expression or cell function. Epitalon is grouped with other synthetic short peptides under this label. The term reflects a proposed mechanism rather than an established drug classification.
It is based on epithalamin, a peptide-rich preparation obtained from pineal gland tissue and studied in the former Soviet Union. Researchers later identified the tetrapeptide AEDG as a constituent fragment of that material. Modern supplies are produced by chemical synthesis rather than tissue extraction.