Epitalon vs Thymalin
Epitalon (Synthetic tetrapeptide (pineal bioregulator)) and Thymalin (Thymic peptide fraction) are documented as co-studied in the PeptiDex library. This page puts the two entries side by side on class, molecular weight, half-life, origin, mechanism and studied research areas — every value taken from the entry it belongs to.
Why these two are co-studied
Cross-referenced for research context — not a usage or combination recommendation.
At a glance
| Attribute | Epitalon | Thymalin |
|---|---|---|
| Compound class | Synthetic tetrapeptide (pineal bioregulator) | Thymic peptide fraction |
| Research category | Longevity & Cellular | Longevity & Cellular |
| Length (amino acids) | 4 amino acids | Not documented |
| Molecular weight | 390.35 g/mol | Not documented |
| Half-life | Not documented | Not documented |
| Origin | Epitalon (also spelled Epithalon) is a synthetic tetrapeptide developed in Russia by Vladimir Khavinson and colleagues, designed as a short-peptide analog derived from studies of the pineal extract Epithalamin. It emerged from Russian peptide bioregulator research aimed at tissue-specific regulatory peptides. | Thymalin is a peptide preparation derived from a fraction of calf (bovine) thymus tissue, developed in Russia as a thymic bioregulator. It is a polypeptide/peptide complex rather than a single defined-sequence peptide. |
“Not documented” means the PeptiDex entry records no value for that field. Nothing on this page is estimated, and no figure is carried over from one compound to the other.
How Epitalon works
Epitalon is proposed to act as a peptide bioregulator influencing gene expression and pineal function. Reported preclinical mechanisms include modulation of the pineal gland and melatonin regulation, and studies have described effects on telomerase activity and telomere length in cultured human cells. The precise molecular mechanism in vivo is not fully established, and much of the mechanistic data comes from cell-culture and animal models.
How Thymalin works
Thymalin is described as a thymic peptide preparation reported to modulate immune function, particularly influencing T-lymphocyte differentiation and the balance of immune cell populations. As a mixture of thymic peptides, its actions are attributed to restoring or regulating immune parameters in preclinical and clinical research from the Russian literature. The precise molecular targets are not fully defined given its nature as a peptide fraction.
Mechanistic descriptions reflect published research-literature understanding and are quoted from each compound's own entry. Much peptide research is preclinical (in-vitro or animal-model); mechanism in humans may differ and is not established for many compounds.
Where each one appears in the literature
The research contexts each entry documents. Listing a research area is not a claim of efficacy or a therapeutic indication, and the two lists are not scored against each other.
Epitalon
Thymalin
What sets each apart
Epitalon
Epitalon is a defined 4-amino-acid pineal bioregulator peptide, distinct from thymic peptides (immune focus) and mitochondrial peptides, with a research emphasis on telomere/telomerase biology.
Thymalin
Unlike Thymosin alpha-1 (a single, defined 28-residue peptide), Thymalin is a multi-peptide thymic tissue fraction, so it has no single sequence or molecular weight.
Frequently asked questions
What is epitalon and what is it studied for?
Epitalon (epithalon) is a synthetic tetrapeptide, Ala-Glu-Asp-Gly, modeled on the pineal peptide epithalamin. It is studied in aging research for reported effects on telomerase activity, telomere length, circadian/melatonin regulation, and antioxidant markers, largely in older Russian experimental programs and cell/animal models.
What is the sequence and molecular weight of epitalon?
Epitalon is the tetrapeptide Ala-Glu-Asp-Gly (AEDG), with molecular formula C14H22N4O9 and a molecular weight of about 390.35 g/mol. Its short four-residue length is one reason it is thought to have a very brief systemic half-life.
How is epitalon cycled in research protocols?
Reported research and community protocols use short cycles rather than continuous dosing, commonly a 10-20 day course repeated once or twice per year. Cycling reflects the older Russian research design of intermittent short courses rather than daily long-term administration.
What is thymalin?
Thymalin is a low-molecular-weight polypeptide fraction extracted from calf (bovine) thymus, developed in Russia by Khavinson and Morozov. It is a heterogeneous complex of short peptides rather than a single defined molecule, and is studied as an immunomodulator that reportedly normalizes rather than simply boosts immune parameters.
How does thymalin differ from thymosin alpha-1?
Thymosin alpha-1 is a single, chemically defined 28-amino-acid peptide with a known sequence, whereas thymalin is a defined-process but undefined-composition extract containing a mixture of thymic peptides. Batch-to-batch peptide ratios can vary in thymalin, unlike the single synthetic molecule of thymosin alpha-1.
What is thymalin studied for?
Thymalin is studied in immune-senescence and aging research for reported restoration of T-cell counts, CD4/CD8 ratios, and NK-cell activity in older populations. Khavinson-era observational studies also reported reduced mortality in elderly cohorts, though these were non-randomized and are considered preliminary.
Answers are the ones published on each compound's own PeptiDex entry. They are educational summaries of research-literature context and are not medical advice.