If you have been reading about AEDG and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2025-09-01. Numbers and descriptions here follow the published literature rather than marketing material.
The molecule is a short, linear, hydrophilic peptide that dissolves readily in water or aqueous buffer. Its principal chemical liabilities are hydrolytic rather than oxidative, since it contains no cysteine, methionine, or tryptophan residues. The aspartate–glycine step is a recognised site for aspartimide formation under mildly acidic or basic conditions, generating isoaspartate and succinimide-related products over time. Desiccated lyophilised powder held at −20 °C is comparatively stable, whereas dilute solutions degrade faster and are best frozen as single-use aliquots rather than thawed repeatedly.
No pharmacopoeial monograph exists for this peptide, so quality rests on the supplier's internal specifications and on whatever independent testing a purchaser arranges. Certificates of analysis differ widely in which tests they report and in the limits applied. The counter-ion introduced during purification, commonly acetate or trifluoroacetate, changes the net peptide content of a given mass of powder, so two samples of equal weight may not contain equal amounts of the active sequence. Third-party laboratories can verify purity, identity, residual solvents, and counter-ion content for a fee, which makes documentation more informative than labelling.
Verification of a sample usually begins with reversed-phase high-performance liquid chromatography, which resolves the peptide from truncated sequences and other impurities and expresses purity as a percentage of total peak area. Mass spectrometry by electrospray ionisation or matrix-assisted laser desorption supplies an independent check, because the measured mass can be compared against the theoretical value for AEDG. Amino acid analysis or tandem mass spectrometry sequencing can confirm residue order. Each of these methods answers a different question: a purity figure does not establish identity, and an identity match does not establish how much of the material is intact peptide.
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.
| Property | Value | Notes |
|---|---|---|
| Identity confirmation | Electrospray or MALDI mass spectrometry | Observed mass compared with theoretical 390.35 Da |
| Purity specification | 95 percent or greater by RP-HPLC | Common convention for research-grade peptide |
| Counter-ion | Acetate or trifluoroacetate | Affects net peptide content of a weighed sample |
| Solution storage | −80 °C as single-use aliquots | Repeated freeze–thaw cycles accelerate loss |
| Main degradation route | Aspartimide formation at Asp-Gly | Produces isoaspartate and related species |
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.
Epitalon emerged from research conducted in Saint Petersburg by Vladimir Khavinson and colleagues, who studied short peptides as potential regulators of aging. The work built on epithalamin, a pineal gland extract reported to influence neuroendocrine function. Epitalon was designed as a synthetic counterpart with a defined sequence, allowing reproducible experiments that extracts could not support. Early publications described effects on melatonin rhythms and lifespan in animal models. These findings circulated mainly in Russian-language journals during the 1990s, which limited their visibility among English-speaking researchers.
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.
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.
Freeze-dried epitalon is normally kept at minus twenty degrees Celsius in a sealed, desiccated container, protected from light. Short excursions at ambient temperature during shipping are generally tolerated, but repeated warming and cooling cycles encourage moisture uptake, which shortens shelf life. Once dissolved, the peptide is far less stable than the solid: aqueous solutions are subject to hydrolysis and to deamidation at the aspartate and glutamate residues. Working solutions are therefore held refrigerated and used within days, and repeated freezing and thawing of the same vial is best avoided.
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.
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.
==== Biosynthesis ==== L-Quisqualic acid is a glutamate receptor agonist, acting at AMPA receptors and metabotropic glutamate receptors positively linked to phosphoinositide hydrolysis. It sensitizes neurons in hippocampus to depolarization by L-AP6. Being a 3,5-disubstituted oxadiazole, quisqualic acid is a stable compound. One way of synthesizing quisqualic acid is by enzymatic synthesis. Therefore, cysteine synthase is purified from the leaves of Quisqualis indica var. villosa, showing two forms of this enzyme. Both isolated isoenzymes catalyse the formation of cysteine from O-acetyl-L-serine and hydrogen sulphide, but only one of them catalyses the formation of L–quisqualic acid.
=== Food additives === Potassium sodium tartrate (KNaC4H4O6, Rochelle salt) is a main constituent of some varieties of baking powder; it is also used in the silvering of mirrors. Potassium bromate (KBrO3) is a strong oxidizer (E924), used to improve dough strength and rise height. Potassium bisulfite (KHSO3) is used as a food preservative, for example in wine and beer-making (but not in meats). It is also used to bleach textiles and straw, and in the tanning of leathers.
Higher methylation levels in rRNA genes in the hippocampus of the brain results in a lower production of proteins and thus limited hippocampal function can result in learning and memory impairment and resultant suicidal tendencies. In a study comparing genetic differences between healthy people and psychiatric patients 60 different epigenetic markers associated with brain cell signaling were found. Environmental factors such as child abuse appears to cause the expression of an epigenetic tag on glucocorticoid receptors (associated with stress responses) that was not found in suicide victims. This is an example of experience-dependent plasticity. Environmental enrichment in individuals is associated with increased hippocampal gene histone acetylation and thus improved memory consolidation (notably spatial memory).
Sources: en.wikipedia.org
==== Psychedelics ==== The Zendo Project conducted by the Multidisciplinary Association for Psychedelic Studies uses principles from psychedelic therapy to provide safe places and emotional support for people having difficult experiences on psychedelic drugs at select festivals such as Burning Man, Boom Festival, and Lightning in a Bottle without medical or law enforcement intervention.
== Medical application == S. helianthus shows a variety of promising applications in the medical field due to its toxin-producing capability. ShK-186, a peptide inhibitor, is a toxin that has been previously implemented in clinical trials for its potential treatment of autoimmune diseases. It has been further developed into an “investigational drug”, known as Dalazatide, in which it targets the disease-causing cells corresponding to ailments including type 1 diabetes, lupus erythematosus and multiple sclerosis. The aforementioned cytolysins, St I and St II, have also shown pharmacological potential in studies with guinea pig models, with direct implications on neural and cardiac activity. Due to its capability of protease inhibition, ShPI-1 is another toxin with medical potential. This toxin is a “non-specific inhibitor” and provides a variant with “increased biomedical potential” for its inhibition properties. Though many of these toxins require further research, S. helianthus serves great potential in biomedical applications for toxin production.
leucine zipper (ZIP) A common structural motif in DNA-binding transcription factors and some other types of proteins, approximately 35 amino acids in length, characterized chiefly by the recurrence of the amino acid leucine every seven residues. When modeled in an idealized alpha-helical conformation, the leucine residues are positioned in such a way that they can interdigitate with the same or similar motifs in an alpha helix belonging to another similar polypeptide, facilitating dimerization and the formation of a complex resembling a zipper.
At the ends of the linear chromosomes are specialized regions of DNA called telomeres. The main function of these regions is to allow the cell to replicate chromosome ends using the enzyme telomerase, as the enzymes that normally replicate DNA cannot copy the extreme 3′ ends of chromosomes. These specialized chromosome caps also help protect the DNA ends, and stop the DNA repair systems in the cell from treating them as damage to be corrected. In human cells, telomeres are usually lengths of single-stranded DNA containing several thousand repeats of a simple TTAGGG sequence. These guanine-rich sequences may stabilize chromosome ends by forming structures of stacked sets of four-base units, rather than the usual base pairs found in other DNA molecules. Here, four guanine bases, known as a guanine tetrad, form a flat plate. These flat four-base units then stack on top of each other to form a stable G-quadruplex structure. These structures are stabilized by hydrogen bonding between the edges of the bases and chelation of a metal ion in the centre of each four-base unit. Other structures can also be formed, with the central set of four bases coming from either a single strand folded around the bases, or several different parallel strands, each contributing one base to the central structure. In addition to these stacked structures, telomeres also form large loop structures called telomere loops, or T-loops. Here, the single-stranded DNA curls around in a long circle stabilized by telomere-binding proteins.
Sources: en.wikipedia.org
== Partial list of peptide hormones in humans == Adrenocorticotropic hormone (ACTH) Adropin Amylin Angiotensin Atrial natriuretic peptide (ANP) Calcitonin Cholecystokinin (CCK) Gastrin Ghrelin Glucagon Glucose-dependent insulinotropic polypeptide (GIP) Glucagon-like peptide-1 (GLP-1) Growth hormone Follicle-stimulating hormone (FSH) Human chorionic gonadotropin (hCG) Insulin Leptin Luteinizing hormone (LH) Melanocyte-stimulating hormone (MSH) Orexin/Hypocretin Oxytocin Parathyroid hormone (PTH) Prolactin Renin Somatostatin Thyroid-stimulating hormone (TSH) Thyrotropin-releasing hormone (TRH) Vasopressin, also called arginine vasopressin (AVP) or anti-diuretic hormone (ADH) Vasoactive intestinal peptide (VIP) Somatotropin (GH1) Gonadotropin Releasing Hormone 1 (GNRH1) Gonadotropin Releasing Hormone 2 (GNRH2) Growth Hormone Releasing Hormone (GHRH) Parathyroid Hormone Like Hormone (PTHLH) Corticotropin Releasing Hormone (CRH) Anti-Müllerian Hormone (AMH) Chorionic Somatomammotropin Hormone 1 (CSH1) Chorionic Somatomammotropin Hormone 2 (CSH2) Pro-Melanin Concentrating Hormone (PMCH) Resistin (RETN)
In his psychological theory—which is not necessarily linked to a particular theory of social structure—the persona appears as a consciously created personality or identity, fashioned out of part of the collective psyche through socialisation, acculturation and experience. Jung applied the term persona because, in Latin, it means both personality and the masks worn by Roman actors of the classical period, expressive of the individual roles played. The persona, he argues, is a mask for the "collective psyche", a mask that 'pretends' individuality so that both self and others believe in that identity, even if it is really no more than a well-played role through which the collective psyche is expressed. It has also been referred to as the social archetype or the conformity archetype. Jung regarded the "persona-mask" as a complicated system that mediates between individual consciousness and the social community: it is "a compromise between the individual and society as to what a man should appear to be". But he also makes it quite explicit that it is, in substance, a character mask in the classical sense known to theatre, with its double function: both intended to make a certain impression on others and to hide (part of) the true nature of the individual, which he calls the 'shadow'. The therapist then aims to assist the individuation process through which the client (re)gains their "own self"—by liberating the self, both from the deceptive cover of the persona and from the power of unconscious impulses.
The outer chloroplast membrane is a semi-porous membrane that small molecules and ions can easily diffuse across. However, it is not permeable to larger proteins, so chloroplast polypeptides being synthesized in the cell cytoplasm must be transported across the outer chloroplast membrane by the TOC complex, or translocon on the outer chloroplast membrane. The chloroplast membranes sometimes protrude out into the cytoplasm, forming a stromule, or stroma-containing tubule. Stromules are very rare in chloroplasts, and are much more common in other plastids like chromoplasts and amyloplasts in petals and roots, respectively. They may exist to increase the chloroplast's surface area for cross-membrane transport, because they are often branched and tangled with the endoplasmic reticulum. When they were first observed in 1962, some plant biologists dismissed the structures as artifactual, claiming that stromules were just oddly shaped chloroplasts with constricted regions or dividing chloroplasts. However, there is a growing body of evidence that stromules are functional, integral features of plant cell plastids, not merely artifacts.
This poses a real challenge for the translators because they have to render the meaning, i.e. find an equivalent, of a very specific, scientific term in the target language and frequently the narrator uses a more general name instead of a specific term and the translator has to rely on the image presented in the programme to understand which term is being discussed in order to transpose it in the target language accordingly. Additionally, translators of minorised languages often face another problem: some terms may not exist in the target language. In such cases, they have to create new terminology or consult specialists to find proper solutions. Also, sometimes the official nomenclature differs from the terminology used by actual specialists, which leaves the translator to decide between using the official vocabulary that can be found in the dictionary, or rather opting for spontaneous expressions used by real experts in real-life situations.
== Global locations == Arby's currently has locations in Canada, Costa Rica, Saudi Arabia, Egypt, Mexico, South Korea, Turkey, and the United States (in every state except Rhode Island and Vermont). There are also Arby's locations for service members in the Kadena Air Base and Camp Foster in Okinawa, Japan.
Sources: en.wikipedia.org
Mass spectrometry provides the identity check, because the observed mass is compared with the theoretical mass of the AEDG sequence. Chromatography separates and quantifies impurities but does not by itself prove which peptide is present. The two techniques are normally used together.
Yes. Trifluoroacetate and acetate ions remain associated with the peptide after purification, so a weighed quantity of powder contains less peptide than the nominal mass suggests. Certificates that report net peptide content rather than raw weight are more directly comparable between suppliers.
Dilute aqueous solutions are less stable than the dry powder and are usually aliquoted and frozen to avoid repeated freeze–thaw cycles. Lyophilised material is best stored desiccated at −20 °C, protected from light. Working solutions are typically prepared fresh from a frozen aliquot.
The peptide contains four residues in the order alanine, glutamate, aspartate and glycine, abbreviated AEDG. The chain is linear and held together by three peptide bonds. Its calculated mass for the uncharged free form is about 390.3 daltons.