Epithalon — also written Epitalon and registered in chemistry indices as the tetrapeptide Ala-Glu-Asp-Gly (AEDG), CAS 307297-39-8 — is among the most extensively studied compounds in Russian gerontology research. Originally developed by Prof. Vladimir Khavinson at the St. Petersburg Institute of Bioregulation and Gerontology, Epithalon is the synthetic short-peptide analog of epithalamin, a pineal-gland extract first characterised in the 1970s. Its principal research interest lies in a single mechanism: telomerase activation and the downstream question of whether short peptides can influence telomere length in somatic cells.
The Khavinson Bioregulator Programme
Epithalon is one of approximately 20 short peptides — collectively the "Khavinson peptides" or "cytomax/cytogen bioregulators" — isolated and synthesised during a decades-long Soviet and Russian research programme that began at the Military Medical Academy in Leningrad. The underlying hypothesis is straightforward: tissue-specific short peptides, 2–4 amino acids in length, function as gene-regulatory signals that maintain organ-specific cellular function. AEDG was identified as the active fragment of pineal-derived epithalamin.
The programme produced over 200 published preclinical and clinical reports across rodent, primate, and human trials. Major endpoints studied include lifespan extension in mice, telomerase activation in cell culture, melatonin rhythm normalisation, and immune function in elderly cohorts. The literature is largely Russian-language and PubMed-indexed under transliterations including Epitalon, Epithalon, and the chemical descriptor AEDG.
Telomerase and Telomere Length — What the Research Shows
The mechanistic claim that drives most Epithalon research interest is telomerase activation. In somatic cells, telomeres — the protective TTAGGG repeats at chromosome ends — shorten with each division. When they reach a critical length, the cell enters replicative senescence. Telomerase, the ribonucleoprotein complex that elongates telomeres, is normally repressed in adult somatic tissue. Reactivation of telomerase is therefore a central question in longevity research.
Published cell-culture studies (Khavinson et al., 2003; Khavinson and Bondarev, 2003) report measurable telomerase activation in human somatic cell lines exposed to AEDG, with telomere elongation observed across replicative cycles in fibroblast cultures. These findings have been cited in subsequent reviews of small-peptide telomere research, though direct replication outside the Khavinson group is limited and methodological differences make cross-study comparison difficult.
The compound has also been studied for effects on pineal melatonin rhythm. In aged rodent models, AEDG normalises the circadian melatonin curve, which is otherwise blunted with chronological ageing. This pineal-axis effect is the secondary mechanism most cited in the literature.
Physical Properties
| Property | Epithalon (AEDG) |
|---|---|
| Sequence | Ala-Glu-Asp-Gly |
| CAS number | 307297-39-8 |
| Molecular formula | C14H22N4O9 |
| Molecular weight | 390.35 g/mol |
| Appearance | White lyophilised powder |
| Solubility | Bacteriostatic water, sterile saline |
| Storage (lyophilised) | −20 °C, protected from light |
Research Design Considerations
Several methodological points recur across the Epithalon literature and are worth understanding before interpreting any specific paper.
Dose ranges studied
Preclinical rodent studies typically use intraperitoneal or subcutaneous administration at 0.1–1.0 µg per animal per day, cycled over 5–10 days. Cell-culture studies use micromolar concentrations in growth medium. The compound's small size and lack of receptor-pocket binding mean that conventional dose-response curves are often biphasic rather than monotonic.
Endpoints and detection
Telomere length measurements use TRF (terminal restriction fragment) Southern blot or qPCR-based methods. Telomerase activity is most commonly assayed by TRAP (Telomeric Repeat Amplification Protocol). Researchers should be aware that AEDG's effect sizes in the literature are modest — telomerase activation is typically reported as a fold-change over baseline, not an absolute enzymatic value, and replication across laboratories has not been uniformly successful.
Khavinson school vs. Western literature
The bulk of Epithalon clinical literature originates from a single research school, which is a known limitation when assessing strength of evidence. Independent Western replication is sparse. Researchers designing protocols should treat the existing literature as hypothesis-generating rather than definitive.
For accurate replication of published Epithalon protocols, batch-specific COA with HPLC-MS verification is essential. Sub-99% purity introduces tetrapeptide deletion products and oxidation impurities that confound TRAP and Southern blot assays.
Purity and COA Standards
AEDG is a short tetrapeptide and is relatively simple to synthesise via solid-phase peptide synthesis (SPPS). Despite this, commercial preparations vary substantially in purity. Research-grade Epithalon should meet:
- ≥99% HPLC purity (reverse-phase, UV 220 nm detection)
- Mass spectrometry confirmation at the expected molecular ion (m/z 391.4, [M+H]+)
- Batch-specific COA documenting both, not generic catalog data
- Residual TFA below 0.5% (typical SPPS byproduct)
The two impurity classes most likely to confound AEDG research are deletion sequences — particularly tripeptide AED and EDG fragments — and aspartate side-chain isomerisation products. Both are HPLC-resolvable and should be quantified in a complete COA.
Epithalon in the Broader Khavinson Catalog
Researchers working on multi-peptide longevity protocols often encounter Epithalon alongside other Khavinson short peptides such as Pinealon (Glu-Asp-Arg, EDR — also pineal-axis), Thymalin (thymus, immune), and Cortexin (cortical, CNS). The bioregulator framework treats these as a class with overlapping but distinct tissue specificity. Most laboratories evaluating Khavinson peptide hypotheses focus on Epithalon and Pinealon as the most pharmacologically characterised members.
Epithalon (AEDG) Research Compound
10mg lyophilised · ≥99% HPLC-MS · Batch COA · EU & CIS delivery
View Research Compound →Summary
Epithalon is the synthetic tetrapeptide AEDG, developed within the Khavinson bioregulator programme and studied principally for telomerase activation and pineal melatonin-axis effects. The cell-culture and rodent literature is extensive but largely originates from a single research school; independent replication outside the Khavinson group is limited. For laboratories assessing the telomerase hypothesis or pineal-axis modulation, AEDG remains the canonical tool compound. Research-grade material should meet ≥99% HPLC purity with batch-specific COA documentation.