Epithalon

Research summary

Epithalon, also spelled Epitalon, is a synthetic tetrapeptide (Ala-Glu-Asp-Gly, or AEDG) designed from the amino-acid composition of epithalamin, a polypeptide extract of bovine pineal gland. It is best known for cell-culture studies reporting telomerase activation and telomere elongation, and for rodent and primate studies of aging markers and melatonin. Most of this research comes from one Russian group, and independent replication is limited.

Also known as

Epitalon · Epithalone · AEDG peptide · Ala-Glu-Asp-Gly

Sequence

Ala-Glu-Asp-Gly

What is Epithalon (Epitalon)?

Epithalon is the four-amino-acid peptide Ala-Glu-Asp-Gly. It was synthesized on the basis of the amino-acid composition of epithalamin, a bovine pineal gland extract, and appears in the literature as Epitalon, Epithalon and Epithalone¹. Its developers, Vladimir Khavinson's group at the St. Petersburg Institute of Bioregulation and Gerontology, later reported detecting AEDG among the tetrapeptides of a pineal polypeptide complex by mass spectrometry².

Over roughly 25 years the peptide has been studied in vitro, in vivo and in silico, with reported effects on melatonin synthesis, interleukin-2 mRNA and the activity of enzymes including acetylcholinesterase and telomerase; reviewers note it remains uncertain whether these are its only mechanisms¹. A 2026 narrative review by US clinicians, which assesses synthetic Epitalon separately from the older epithalamin studies, concludes that it is biologically active but clinically unproven³.

Telomerase and telomere research

The finding most often linked to Epitalon is a 2003 study in which adding the peptide to telomerase-negative human fetal fibroblasts induced expression of the telomerase catalytic subunit, telomerase activity and telomere elongation⁴. A follow-up by the same group reported that treated fetal lung fibroblasts, whose telomeres had shortened with passaging, regained telomere length and went through ten more passages than controls while still dividing⁵.

For years these results came almost entirely from the same group. In 2025 a group at Brunel University London reported concentration-dependent telomere extension in normal human epithelial cells and fibroblasts through upregulation of hTERT and telomerase. In two breast cancer cell lines, telomeres also lengthened, but through the alternative lengthening of telomeres (ALT) pathway⁶. Because sustained telomere maintenance is also how cancer cells keep dividing, the cancer-cell result is a caution as much as a confirmation.

Animal and primate studies

In female SHR mice given Epitalon from three months of age until natural death, the peptide did not change food intake, body weight or mean life span. It did reduce chromosome aberrations in bone marrow cells and extended the life span of the last 10% of survivors by 13.3%; total tumor incidence was unchanged, while leukemia was less frequent⁷.

In old rhesus monkeys, Epitalon lowered basal glucose and insulin, raised night-time melatonin and changed the response to a glucose challenge, with no effect in young animals⁸. A perifusion study in a Paris laboratory, however, found that the tetrapeptide did not change melatonin secretion from isolated pineal glands of young or old rats, even after stimulation with isoproterenol⁹. One measured circulating hormone in living animals and the other glands in vitro, so the results are not strictly contradictory, but the melatonin question is not settled.

Other cell work includes a Chinese study in which Epitalon added to the culture medium of post-ovulatory mouse oocytes reduced reactive oxygen species, spindle defects and apoptosis during in vitro aging¹⁰, and a Russian-Italian study reporting higher expression of neuronal differentiation markers such as Nestin and GAP43 in human gingival mesenchymal stem cells¹¹.

Limitations of the evidence

Most Epitalon studies come from Khavinson's institute and close collaborators in St. Petersburg. Replication by unrelated laboratories is limited to a handful of cell studies^6,10. Human evidence consists of small physiological or biomarker studies and an older study in retinitis pigmentosa; no adequately powered randomized trial exists, and pharmacokinetic and long-term safety data are inadequate³.

• Telomere findings come from cultured cells, not from measurements in whole organisms^4,6.
• The lifetime mouse study found no change in mean life span⁷.
• Melatonin findings differ between in vivo and in vitro models^8,9.
• Epitalon is not FDA-approved; a 2026 review notes unresolved regulatory and product-quality questions after an FDA advisory review³.

Sourcing Epithalon for research

Epithalon sits in our bioregulators range alongside Pinealon. Every lot is independently tested and ships from the USA with a lot-matched certificate of analysis showing HPLC purity and mass-spec identity, published in our certificate library. For other compounds used in cellular-aging research, see NAD+ and MOTS-c.

Further reading

• Epitalon vs Pinealon: Comparing Two Khavinson Bioregulator Peptides
• Peptide Storage and Stability: How to Store Lyophilized Peptides