Livagen

Livagen (KEDA, Lys-Glu-Asp-Ala) is a synthetic tetrapeptide developed by Prof. Vladimir Khavinson and colleagues at the St. Petersburg Institute of Bioregulation and Gerontology, positioned as a liver-tissue-focused member of the institute's "cytogen" line of single-sequence synthetic bioregulator peptides — the same broad research program that produced Vilon (thymus), Glandokort (adrenal, a "cytomax" natural complex rather than a cytogen), and Epithalon (pineal gland), all also built on this site.

Chemically, Livagen is a four-residue peptide: molecular formula C18H31N5O9, molecular weight approximately 461.46 g/mol, CAS number 195875-84-4. As with the other Khavinson cytogen peptides in this catalog, its defining research premise is that a very short, tissue-derived amino acid sequence can exert tissue-selective effects on gene expression, in this case specifically in liver (hepatic) cells.

At Verified Peptides, we want to note directly that Livagen's published evidence base is, even by the standards of this already thinly-evidenced peptide-bioregulator family, quite narrow: we located essentially one dedicated experimental study specific to Livagen, plus its inclusion in the institute's broader review literature on the bioregulator class as a whole. We present what that research actually shows below, without inflating it beyond what the primary source supports.

The broader research context Livagen sits within is well-established independent of Khavinson's own work: age-related decline in hepatocyte protein synthesis capacity is a recognized feature of liver aging in mainstream hepatology and gerontology research, linked to reduced ribosomal biogenesis, mitochondrial decline, and accumulated cellular damage in aging liver tissue. This general phenomenon — that older liver cells synthesize protein less efficiently than younger ones — is not a Khavinson-specific claim; it is the backdrop against which Livagen's proposed liver-tissue-restorative effect is framed, even though the specific claim that a Lys-Glu-Asp-Ala tetrapeptide can reverse this decline via direct chromatin interaction remains a claim substantially developed by, and evidenced within, one research program.

At Verified Peptides, we located one dedicated experimental study specific to Livagen: "Rhythm of protein synthesis in cultures of hepatocytes from rats of different ages: norm and effect of the peptide livagen" (Izvestiya Akademii Nauk, Seriya Biologicheskaya, 2001, PMID 15926314). This study examined protein-synthesis rhythms in hepatocyte cultures from rats of different ages, both under normal conditions and following Livagen treatment, reporting that Livagen increased protein synthesis levels across ages, with the largest effect in hepatocytes from old rats, and that a comparison peptide (Epithalon) produced no such effect in the same assay.

Beyond this specific study, Livagen appears in the institute's broader review literature on the peptide-bioregulator class, including Khavinson and Kuznik's "Peptide bioregulators: the new class of geroprotectors" (PMID 23734519), which summarizes decades of the group's animal and cell-culture research across its full organ-specific bioregulator catalog, including liver-focused compounds like Livagen, without providing extensive Livagen-specific detail beyond what the dedicated 2001 study reported.

We want to be direct with researchers about what this means in practice: Livagen's evidence base consists, to our knowledge, of a single dedicated rat hepatocyte culture study plus its mention within a broader self-authored review, both originating from the same institute that developed and commercially sells the compound. We are not aware of any independent replication of the hepatocyte protein-synthesis findings by researchers outside Khavinson's group, any study in a species other than rat, or any human clinical research — registered or published — involving Livagen. This places Livagen's evidence base at the narrower end of the Khavinson bioregulator peptides built on this site so far, and researchers should weigh it accordingly rather than assume the broader bioregulator program's claims automatically transfer to strong, compound-specific support for Livagen.

No FDA, EMA, or other Western regulatory body has evaluated or approved Livagen for any indication. At Verified Peptides, we sell research-grade Livagen exclusively for laboratory research, consistent with its current, narrowly preclinical evidence status.

Livagen's four-letter shorthand, KEDA, follows the standard single-letter amino acid code for its sequence (Lysine-Glutamic acid-Aspartic acid-Alanine), a naming convention used consistently across several of Khavinson's short cytogen peptides, similarly to how Vilon is shorthanded as KE for Lys-Glu.

Livagen is one of several liver-focused compounds within the broader Khavinson bioregulator catalog; a related but distinct compound called Ovagen, associated with reproductive/ovarian tissue research rather than liver, is sometimes discussed alongside it in vendor literature due to naming similarity, but the two are unrelated compounds targeting entirely different organ systems, illustrating a naming-confusion risk researchers should watch for across this catalog of similarly-styled product names.

The dedicated hepatocyte study behind most of what is known about Livagen specifically examined rhythmic (time-of-day-dependent) patterns in hepatocyte protein synthesis, not simply a single static measurement, reporting that Livagen affected the amplitude of these rhythmic fluctuations in aged rat hepatocytes rather than simply raising protein synthesis to a flat higher level — a more nuanced finding than a simple "increases protein synthesis" summary conveys, and one that researchers interested in circadian or rhythmic aspects of hepatic aging may find specifically relevant.

As with other single-sequence Khavinson cytogens, Livagen's small size (four residues) is central to its proposed mechanism of direct nuclear entry and chromatin interaction, a proposed mode of action that, if broadly true, would be unusual relative to how most larger peptide hormones and growth factors in this catalog are understood to act via cell-surface receptor binding rather than direct intranuclear chromatin interaction.

Like several other names on the Phase 4 build list, Livagen traces back to a broader Khavinson bioregulator research program reported to have originated in Soviet military-funded research beginning in the 1970s, which investigated tissue-extract peptides for functional resilience in populations under sustained physiological stress before the work was reoriented toward civilian aging and organ-function research. Livagen's specific liver-focused branch of that program appears to have been developed and characterized considerably later than some other cytogens in the catalog, such as Epithalon and Vilon, which is consistent with its comparatively narrower published research footprint.

At Verified Peptides, we require independent third-party HPLC purity testing and mass spectrometry identity confirmation for every batch of research-grade Livagen we offer, with a Certificate of Analysis (COA) available for each lot. As a four-residue peptide, Livagen is straightforward to synthesize to high purity using standard solid-phase peptide synthesis methods, but batch verification remains important for consistent, reproducible research results.

We source exclusively from manufacturers operating under Good Manufacturing Practice (GMP)-aligned quality systems, and every lot is independently verified rather than accepted solely on a supplier's internal documentation. Researchers should always request and review the specific COA for the lot they receive, confirming purity percentage and molecular identity before use in any experimental protocol.

Lyophilized Livagen is stable when stored at -20°C, protected from light and moisture, and researchers can generally expect the unreconstituted peptide to maintain integrity over an extended period under these conditions. At Verified Peptides, we ship lyophilized peptide with appropriate cold-chain packaging to preserve stability in transit.

Once reconstituted with bacteriostatic water or another appropriate sterile diluent, Livagen solution should be stored refrigerated at 2–8°C and used within the timeframe indicated on the product's documentation. As with other short peptides in this catalog, reconstituted solutions are generally less stable than the lyophilized form and are more susceptible to degradation and microbial contamination with repeated freeze-thaw cycling.

Researchers should avoid repeated freeze-thaw cycles of reconstituted material and should follow the specific storage guidance provided with each lot's documentation to preserve sample validity for research use.

Because Livagen's evidence base rests on a single published study, researchers designing new experimental work with this compound should pay particular attention to replicating the original study's exact handling and reconstitution conditions where possible, since deviations in preparation method have not been separately validated against the original 2001 hepatocyte findings and could introduce an additional, uncharacterized source of variability into results.