The short version of Peptide storage fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-05-13. Anything still debated is marked as such rather than presented as settled.
Epitalon is the common name for a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, usually abbreviated AEDG. All four residues are proteinogenic amino acids, and the free peptide has a calculated mass near 390 grams per mole. Because the chain is short and carries no modifications, it is assembled readily by solid-phase synthesis and is distributed mainly as a freeze-dried solid for laboratory work. Catalogue listings use the spellings epitalon, epithalone, and simply AEDG, and the three refer to the same sequence.
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.
Identity and purity are checked by reversed-phase high-performance liquid chromatography, usually with ultraviolet detection near 214 nanometres, where the peptide bond absorbs. Mass spectrometry confirms the expected mass and reveals whether truncation products or adducts are present. Acid hydrolysis followed by amino acid analysis gives the residue ratio, which should approximate one alanine, one glutamate, one aspartate and one glycine. Counter-ions such as acetate or trifluoroacetate remain in the dried product and lower net peptide content, so a stated purity figure on a label does not by itself describe how much peptide a vial holds.
Regulatory treatment differs by country. No formulation of epitalon holds a marketing authorisation as a medicine in the United States or the European Union, where material sold for laboratory use is handled as a research chemical and is not intended for human consumption. In Russia, several short peptide preparations from the same institute's peptide series are registered medicinal products, and epitalon appears in that national context. Elsewhere it is frequently offered as a cosmetic ingredient, a category with lighter requirements. Advertising claims about longevity or disease prevention are restricted in most jurisdictions, which limits how sellers describe the compound.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Computed for the free acid of Ala-Glu-Asp-Gly |
| Molecular mass | About 390.35 g/mol | Free peptide; salt forms shift the value |
| Appearance | White to off-white solid | Typical of short peptides after freeze-drying |
| Solubility class | Freely soluble in water | Aqueous buffers are also commonly used |
| Common synonyms | Epitalon, epithalone, AEDG | AEDG is the single-letter sequence |
Published studies on epitalon are dominated by a small number of research groups, and independent replication in other laboratories remains limited. Proposed mechanisms include activation of telomerase and modulation of melatonin rhythms, but the evidence for either rests mainly on cell cultures and animal models. Whether the peptide produces comparable effects in humans is an open question, and the absence of large controlled trials means the literature is best read as exploratory rather than settled.
Epitalon is a synthetic four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9, and its calculated molar mass is approximately 390.35 grams per mole. The compound is a short fragment related to a peptide fraction isolated from bovine pineal gland extracts, and it is normally supplied as a lyophilised powder intended for laboratory research. It is not a registered pharmaceutical product in most countries.
The peptide emerged from research carried out in Saint Petersburg from the late 1980s onward, where investigators searched for shorter active fragments of a pineal preparation known as epithalamin. The name epitalon was chosen to reflect that parent extract. Early reports described effects on neuroendocrine markers and on the lifespan of laboratory animals. Much of that work appeared in Russian-language journals, with English translations following later, which affects how readily the original protocols can be assessed by outside groups.
The most widely cited claim is that epitalon activates telomerase and thereby extends telomere length. Supporting evidence comes largely from cultured human cells, where treatment was associated with increased telomerase activity and delayed replicative senescence. Telomerase activation is a biologically consequential effect, since the enzyme is largely silenced in most somatic cells. However, the route by which a short peptide would reach and act on the enzyme's regulatory machinery has not been established. Independent replication in human trials is scarce, so the link between cell-culture observations and whole-body aging remains an open question.
Human data are limited to small studies, often without the randomization, blinding, or control groups expected in contemporary clinical research. Reported outcomes have included changes in melatonin levels, immune markers, and subjective measures, but sample sizes were generally too small to support firm conclusions. Some reviews treat the peptide as promising while noting methodological weaknesses; others question whether the observed effects are specific. The compound is frequently discussed in longevity-focused communities, where enthusiasm often outpaces the published evidence. Separating established findings from speculation is therefore important when reading summaries of this research.
== History == The first example of a palladium catalyzed coupling of aryl halides with organotin reagents was reported by Colin Eaborn in 1976. This reaction yielded from 7% to 53% of diaryl product. This process was expanded to the coupling of acyl chlorides with alkyl-tin reagents in 1977 by Toshihiko Migita, yielding 53% to 87% ketone product.
In theory, many cancers might be prevented in this way, since an excess of thyroid cancer, presumably due to radioiodine uptake, is the only proven long-term effect after exposure of a population to radioactive fission products from a reactor accident or atomic bomb fallout. Taking large amounts of iodide saturates thyroid receptors and prevents uptake of most radioactive iodine-131 that may be present from fission product exposure (although it does not protect from other radioisotopes, nor from any external radiation). The protective effect of KI lasts approximately 24 hours, so must be dosed daily until a risk of significant exposure to this isotope no longer exists; as it decays relatively rapidly with a half-life of eight days (other iodine isotopes of concern are even shorter-lived), 99.95% of the radioiodine has vanished after three months.
Similarly, ethylene oxide is detected by the bright pink color of the indicator when passing air through aqueous solutions of some salts of sodium or potassium (chlorides, iodides, thiosulfates, etc.) with the addition of phenolphthalein:
== Further reading == Wolfram-Schauerte, Maik; Pozhydaieva, Nadiia; Grawenhoff, Julia; Welp, Luisa M.; Silbern, Ivan; Wulf, Alexander; Billau, Franziska A.; Glatter, Timo; Urlaub, Henning; Jäschke, Andres; Höfer, Katharina (August 16, 2023). "A viral ADP-ribosyltransferase attaches RNA chains to host proteins". Nature. 620 (7976): 1054–1062. Bibcode:2023Natur.620.1054W. doi:10.1038/s41586-023-06429-2. PMC 10468400. PMID 37587340.
Sources: en.wikipedia.org
== External links == "Real-world Evidence from a Narrow Therapeutic Index Product (Levothyroxine) Reflects the Therapeutic Equivalence of Generic Drug Products". U.S. Food and Drug Administration (FDA). 19 November 2020. Archived from the original on 2 October 2020. Levothyroxine pronunciation guide – audio, phonetic spelling, and syllable breakdown
=== Books === 1910 Conflicts in the Child's Soul 1912 Psychology of the Unconscious 1916 Seven Sermons to the Dead (a part of the Red Book, published privately) 1921 Psychological Types 1933 Modern Man in Search of a Soul (essays) 1944 Psychology and Alchemy 1951 Aion: Researches into the Phenomenology of the Self 1952 Symbols of Transformation (revised edition of Psychology of the Unconscious) 1954 Answer to Job 1956 Mysterium Coniunctionis: An Inquiry into the Separation and Synthesis of Psychic Opposites in Alchemy 1957 The Undiscovered Self 1959 Flying Saucers: A Modern Myth of Things Seen in the Skies (Translated by R. F. C. Hull) 1960 Synchronicity: An Acausal Connecting Principle 1962 Memories, Dreams, Reflections (autobiography, co-written with Aniela Jaffé) 1964 Man and His Symbols (Jung contributed one part, his last writing before his death in 1961; the other four parts are by Marie-Louise von Franz, Joseph L. Henderson, Jaffé, and Jolande Jacobi) 2009 The Red Book: Liber Novus (manuscript produced c. 1915–1932) 2020 Black Books (private journals produced c. 1913–1932, on which the Red Book is based)
The protein-rich, alkaline, aqueous fluid within the inner chloroplast membrane and outside of the thylakoid space is called the stroma, which corresponds to the cytosol of the original cyanobacterium. Nucleoids of chloroplast DNA, chloroplast ribosomes, the thylakoid system with plastoglobuli, starch granules, and many proteins can be found floating around in it. The Calvin cycle, which fixes CO2 into G3P takes place in the stroma.
The commercial success of these documentaries may derive from this narrative shift in the documentary form, leading some critics to question whether such films can truly be called documentaries; critics sometimes refer to these works as "mondo films" or "docu-ganda." However, directorial manipulation of documentary subjects has been noted since the work of Flaherty, and may be endemic to the form due to problematic ontological foundations. Documentary filmmakers are increasingly using social impact campaigns with their films. Social impact campaigns seek to leverage media projects by converting public awareness of social issues and causes into engagement and action, largely by offering the audience a way to get involved. Examples of such documentaries include Kony 2012, Salam Neighbor, Gasland, Living on One Dollar, and Girl Rising. Although documentaries are financially more viable with the increasing popularity of the genre and the advent of the DVD, funding for documentary film production remains elusive. Within the past decade, the largest exhibition opportunities have emerged from within the broadcast market, making filmmakers beholden to the tastes and influences of the broadcasters who have become their largest funding source. Modern documentaries have some overlap with television forms, with the development of "reality television" that occasionally verges on the documentary but more often veers to the fictional or staged. The "making-of" documentary shows how a movie or a computer game was produced.
== Physicochemical properties == Polyacrylamide is a polyolefin. It can be viewed as polyethylene with amide substituents on alternating carbons. Unlike various nylons, polyacrylamide is not a polyamide because the amide groups are not in the polymer backbone. Owing to the presence of the amide (CONH2) groups, alternating carbon atoms in the backbone are stereogenic (chiral). For this reason, polyacrylamide exists in atactic, syndiotactic, and isotactic forms, although this aspect is rarely discussed. The polymerization is initiated with radicals and is assumed to be stereorandom.
Sources: en.wikipedia.org
It is a four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine. The chain is unmodified and contains only standard proteinogenic residues, which makes it straightforward to produce by solid-phase synthesis and to characterise by standard peptide methods.
Epitalon and epithalon both circulate, and the difference reflects transliteration of a name coined in Russian-language publications. Reference to the extract it derives from, epithalamin, explains the shared stem. Databases and suppliers are inconsistent, so a search for one spelling alone may miss relevant entries.
No. Epithalamin is a multi-component preparation obtained from pineal tissue, and its exact composition is not fully characterised. Epitalon is a single defined tetrapeptide described as a short synthetic counterpart of that extract, so the two are related in origin but not interchangeable in identity.
The solid is kept cold, dry and dark, typically at minus twenty degrees Celsius, in a sealed container with desiccant. Dissolved material is kept refrigerated and used promptly. Freezing and thawing a solution repeatedly is avoided because it accelerates degradation.