What is livagen?
Livagen is the synthetic tetrapeptide Lys-Glu-Asp-Ala (KEDA), one of the short peptide bioregulators from V. Kh. Khavinson's program at the Saint Petersburg Institute of Bioregulation and Gerontology. The group designed it from an amino acid analysis of liver polypeptide preparations (Brodskii et al., 2001), and its 2022 review table lists it as a hepatoprotector (Khavinson et al., 2022). A PubMed search on 12 October 2026 finds 18 records that name livagen in the title or abstract and one that gives only its sequence.
Nearly all of it comes from one network: the institute and its co-authors, and a Tbilisi State University genetics group that has published with Khavinson. Twelve of the 19 are in Russian. The evidence is cell, tissue and enzyme work plus one study in live rats, and no trial in people is indexed. Disguised Alpha does not currently list livagen; this page is a literature reference for laboratory researchers. Nothing on this page is guidance for use in people.
Livagen reference data
| Property | Value |
|---|---|
| Name | Livagen |
| Also called | Lys-Glu-Asp-Ala; KEDA; H-Lys-Glu-Asp-Ala-OH |
| Structure or sequence | Lys-Glu-Asp-Ala: L-lysyl-L-glutamyl-L-aspartyl-L-alanine, with a free N-terminal amine and a free C-terminal acid |
| Compound class | Synthetic tetrapeptide; a short peptide bioregulator in the Khavinson group's own terms, not a drug class |
| Molecular formula | C₁₈H₃₁N₅O₉ |
| Molecular weight | 461.5 g/mol (monoisotopic mass 461.21 Da) |
| PubChem CID | 87919683 |
Name, formula, weight and the all-L stereochemistry come from PubChem CID 87919683, filed under the name Livagen; the sequence matches the primary papers (Kost et al., 2003).
What the research covers
Six areas follow, each with its model. Most of the work measures chromatin in cultured lymphocytes, not liver function.
Liver explants and cultured hepatocytes
In organotypic culture, livagen stimulated growth of explants of rat liver, the tissue whose peptide complexes were used to design it (Khavinson, 2001). In hepatocyte cultures from rats aged 1 to 24 months, livagen raised protein synthesis, most in cells from old animals, where it also amplified the roughly hourly synthesis rhythm; epitalon did not change synthesis (Brodskii et al., 2001). Models: rat explants and hepatocyte cultures.
Digestive enzymes in young and old rats
The one indexed primary study in live animals looked at digestion. Small-intestine peptide hydrolases did not break livagen down even slightly, and in vitro it cut intestinal glycyl-L-leucine dipeptidase activity by 50%. After two weeks of livagen given by mouth, digestive enzyme activity fell in young rats and rose in old rats, in most cases toward young-control levels (Timofeeva et al., 2005). The abstract gives no group sizes or amounts. Model: young and old rats.
Enkephalin-degrading enzymes in human serum
A Moscow mental health research center, with Khavinson as a co-author, reported that livagen and epitalon inhibited the human serum enzymes that degrade Leu-enkephalin in vitro, with IC50 values of 20 µM for livagen and 500 µM for epitalon. Livagen was more effective than the peptidase inhibitors puromycin, leupeptin and D-PAM, and neither peptide bound mu or delta opioid receptors in rat brain membranes (Kost et al., 2003). Model: human serum and rat brain membranes.
Chromatin in lymphocytes from older donors
Most of the record is chromatin work in cultured lymphocytes, begun by St Petersburg and Tbilisi authors including T. Lezhava. In cells from old people, livagen activated ribosomal genes, decondensed pericentromeric structural heterochromatin and released genes repressed by age-related condensation (Khavinson et al., 2002). In cells from donors aged 75 to 88, all five peptides tested activated ribosomal genes; epitalon, livagen and prostamax also decondensed chromosome 1 pericentromeric heterochromatin, and epitalon and livagen changed chromosome 9 (Khavinson et al., 2004).
Two later Tbilisi abstracts without Khavinson tested livagen with epitalon, cortagen and vilon in lymphocytes from people aged 75 to 88 (and 20 to 40 in 2020), reporting on all four together, and they disagree: the 2020 abstract reports decondensed pericentromeric heterochromatin (Lezhava et al., 2020), the 2023 abstract none (Lezhava et al., 2023). Model: human lymphocyte cultures, not a human study.
Metal ions and lymphocytes from people with disease
In lymphocytes from healthy donors aged 20 to 38 and 75 to 86, in a study co-authored by Lezhava, livagen and epitalon each lessened the effect of nickel, zinc and cobalt ions on chromosome fragile sites, significantly only in the younger donors' cells (Dzhokhadze et al., 2008). In cultures from people with atherosclerosis, which carried more chromosome aberrations, aneuploidy and polyploidy than healthy donors' cultures, livagen alone or with cobalt ions was reported to bring these measures toward normal (Dzhokhadze et al., 2014). Model: human lymphocyte cultures; both papers are in Russian.
Liver injury models, as summarized in a review
The 2022 table cites a 2020 Russian-language review for the hepatoprotector label (Khavinson et al., 2022). That review, co-authored by Khavinson, summarizes in vitro work and animal models of acute and chronic hepatitis and cirrhosis for livagen and for Ventvil, a polypeptide complex extracted from calf liver, and says both normalized immune and antioxidant status (Kuznik et al., 2020). We found no primary report of those animal experiments indexed in PubMed under livagen's name or sequence.
Key studies
- Khavinson VK. "Tissue-specific effects of peptides." Bull Exp Biol Med. 2001. PMID 11713572. Rat explants.
- Brodskii VIa, et al. "Rhythm of protein synthesis in cultures of hepatocytes from rats of different ages. Norm and effect of the peptide livagen." Izv Akad Nauk Ser Biol. 2001. PMID 15926314. Rat hepatocyte cultures; in Russian.
- Kost NV, et al. "Effect of new peptide bioregulators livagen and epitalon on enkephalin-degrading enzymes in human serum." Izv Akad Nauk Ser Biol. 2003. PMID 12942748. Serum enzymes in vitro; in Russian.
- Khavinson VKh, et al. "Effects of short peptides on lymphocyte chromatin in senile subjects." Bull Exp Biol Med. 2004. PMID 15085253. Lymphocyte cultures.
- Timofeeva NM, et al. "Effect of peptide Livagen on activity of digestive enzymes in gastrointestinal tract and non-digestive organs in rats of different ages." Adv Gerontol. 2005. PMID 16075683. Young and old rats; in Russian.
Handling and storage of lyophilized livagen
General laboratory practice for a freeze-dried tetrapeptide, covered in the peptide storage guide and the reconstitution guide:
- Keep the sealed powder at -20°C, dry and protected from light, and let a cold vial reach room temperature before opening.
- With two acidic residues and one basic residue, livagen is an acidic peptide, and the reconstitution guide notes that acidic peptides dissolve best in basic solutions. Test a small portion in water first, add salt or buffer only after it dissolves, and record the pH.
- The storage guide lists aspartic acid residues as prone to hydrolysis, so make solutions fresh, keep single-use aliquots at 2 to 8°C away from light, and avoid freeze-thaw cycles.
- Confirm identity by mass: monoisotopic 461.21 Da, 14.02 Da above testagen. Salt forms weigh more than the free peptide's 461.5 g/mol, so base molarity on the supplier's stated form and content.
Frequently asked questions
What is livagen?
The synthetic tetrapeptide Lys-Glu-Asp-Ala (KEDA), PubChem CID 87919683. Khavinson's group lists it as a hepatoprotector, citing a review rather than a primary study (Khavinson et al., 2022).
Why is livagen linked to the liver?
Its sequence came from an amino acid analysis of liver polypeptide preparations (Brodskii et al., 2001), and it stimulated rat liver explants (Khavinson, 2001). The animal liver-injury work behind its hepatoprotector label appears in a review (Kuznik et al., 2020), not in an indexed primary paper.
Has livagen been tested in people?
PubMed indexes no study in which people received livagen. The human material in its record is donated blood: lymphocytes grown with the peptide and serum enzymes tested in vitro (Kost et al., 2003). Livagen has no Drugs@FDA record and is not an approved drug in the United States (openFDA search, 12 October 2026).
How strong is the evidence on livagen?
Weak. Of the 19 PubMed records naming livagen or its sequence, all but one 2014 record with no author list come from Khavinson's network, including a Tbilisi group that has published with him. Only one primary study used live animals (Timofeeva et al., 2005), and two Tbilisi abstracts disagree on a chromatin endpoint (Lezhava et al., 2023).
How is livagen related to vesugen, testagen and prostamax?
They share the Lys-Glu-Asp core. Vesugen is the tripeptide Lys-Glu-Asp, and livagen, testagen and prostamax add alanine, glycine or proline as a fourth residue (Khavinson et al., 2022).
Does Disguised Alpha sell livagen?
Not currently. Related bioregulators in the catalog: Vesugen, whose three residues open livagen's sequence, and Epitalon, tested beside it in the enzyme and chromatin studies.
Related compounds and guides
- Peptide bioregulators list, A to Z
- Peptide bioregulators explained
- Vesugen research guide and product page
- Epitalon research guide and product page
- Testagen research guide: Lys-Glu-Asp-Gly
- Prostamax research guide: Lys-Glu-Asp-Pro
All Disguised Alpha products are for laboratory research only and are not for human consumption.