N-Acetyl Epithalon Amidate

Addition of the tetrapeptide Epithalon (Ala-Glu-Asp-Gly) to telomerase-negative human fetal fibroblast cultures induced expression of the catalytic subunit of telomerase (hTERT), restored telomerase enzymatic activity, and produced elongation of telomeres. The authors interpret this as reactivation of the silenced telomerase gene in somatic cells. This is the foundational in vitro cell-culture report from the Khavinson group underpinning the telomerase hypothesis for the peptide. As an early single-laboratory study, it has had limited independent replication.

In lab dishes, adding this small pineal-gland peptide to human skin-type cells switched back on telomerase, the enzyme that rebuilds the protective caps (telomeres) on the ends of chromosomes, and the caps grew longer. Because telomere shortening is tied to cellular aging, the researchers suggested the peptide might help cells live longer. It is important to note this comes from a single Russian research group and has not been widely reproduced by independent labs.

Epithalon applied to aging human fetal fibroblast cultures induced telomere elongation to lengths comparable to those seen in early passages and allowed the cells to undergo roughly 10 additional divisions (up to 44 passages) beyond untreated controls, apparently overcoming the Hayflick replicative limit. The effect is attributed to peptide-induced telomerase reactivation and telomere restoration. This extends the group's earlier telomerase findings to replicative capacity. Independent confirmation of Hayflick-limit bypass remains sparse.

Normal human cells can only divide a set number of times before stopping (the Hayflick limit). In this study, treating aging cells with the Epithalon peptide lengthened their chromosome caps and let them divide about 10 extra times before stopping. This suggested the peptide could delay cellular aging in a dish. As with the related work, the results come from the same research group and have not been broadly independently verified.

Female mice given subcutaneous Epithalon from 6 months of age until death showed no change in body weight, food intake, physical activity, or behavior, but exhibited slowed age-related decline in reproductive function, lower body temperature, reduced free-radical (lipid peroxidation) processes, extended lifespan, and decreased spontaneous tumor incidence. The authors frame the peptide as a geroprotector acting partly via antioxidant mechanisms. This is a representative in vivo rodent study from the Anisimov/Khavinson group; independent replication outside this group is limited.

Mice were given the peptide from middle age until the end of life. The treated mice aged more slowly by several measures, lived longer on average, had lower rates of naturally occurring tumors, and showed less oxidative (free-radical) damage, without changes to weight or behavior. This is one of the animal studies used to argue the peptide may slow aging. However, this work comes from the original Russian research group, and strong independent human data are lacking.