Effect of new peptide bioregulators livagen and epitalon on enkephalin-degrading enzymes in human serum
Study of multiple preparations
Enkephalinase inhibition, IC50
Livagen 20 µM; Epitalon 500 µMConcentrations producing 50% inhibition in the serum assay
Opioid-receptor binding
No interaction detected at tested µ- or δ-receptorsRat-brain membrane assay
Livagen and Epitalon inhibited enkephalin breakdown in human serum, with IC50 values of 20 and 500 µM respectively. Neither bound the tested µ- or δ-opioid receptors.
Study notes · methods, sources and limitations
Participants or model Human-serum enzyme assay and rat-brain membrane receptor-binding assay.
Design Human-serum enzyme assay and rat-brain membrane receptor-binding assay.
Important limitations
These are laboratory concentrations and enzyme endpoints, not evidence of opioid-like clinical effects or an effective human dose.
Izvestiia Akademii nauk. Seriia biologicheskaia 2003 · Journal publication
Rhythm of protein synthesis in cultures of hepatocytes from rats of different ages. Norm and effect of the peptide livagen
Study of multiple preparations
Protein synthesis
Increased with Livagen; unchanged with EpitalonCultured rat hepatocytes
Livagen increased protein synthesis in cultured rat liver cells, most strongly in cells from old animals. Epitalon did not change protein-synthesis intensity in this experiment.
Study notes · methods, sources and limitations
Participants or model Cultured hepatocytes from rats aged 1–24 months.
Design Cultured hepatocytes from rats aged 1–24 months.
Age range
1–24 months
Important limitations
The animals supplied cells; this was not a treatment trial in living rats or people.
Izvestiia Akademii nauk. Seriia biologicheskaia 2001 · Journal publication
Functional morphology of an organotypic liver culture exposed to the peptide livagen
Liver-culture morphology
Improved structural preservation and cellular/intracellular regeneration markers reported; numerical size not supplied
Livagen supported liver-cell structural integrity and regeneration-related morphology in an organotypic culture. The abstract supplies no numerical effect size.
Study notes · methods, sources and limitations
Participants or model Organotypic liver culture; sample size and species not supplied in the indexed abstract.
Design Organotypic liver culture; sample size and species not supplied in the indexed abstract.
Important limitations
A tissue-culture result; clinical liver function, fibrosis and patient outcomes were not tested.
Advances in gerontology = Uspekhi gerontologii 2002 · Journal publication
A synthetic four-amino-acid peptide, KEDA, developed in liver-peptide research. Studies examine liver-cell protein synthesis, chromatin and enzymes that break down enkephalins.
KEDA tetrapeptide studied in liver-cell cultures, chromatin assays and enkephalin breakdown. In a human-serum assay its enzyme-inhibition IC50 was 20 µM.
More study findings
Lab research · 2004
Effects of short peptides on lymphocyte chromatin in senile subjects
Study of multiple preparations
Chromatin readouts
Ribosomal-gene activation and decondensation reported; no numerical treatment effect supplied
Five short peptides increased ribosomal-gene activity and altered condensed chromatin in sampled leukocytes. Epitalon, Livagen and Prostamax changed chromosome-1 pericentromeric chromatin; Epitalon and Livagen also changed chromosome 9.
Study notes · methods, sources and limitations
Participants or model Leukocytes sampled from people aged 75–88 years and exposed to peptides in culture.
Design Leukocytes sampled from people aged 75–88 years and exposed to peptides in culture.
Donor ages
75–88 years
Important limitations
People donated cells; they were not treated in a clinical trial. Chromatin changes do not establish rejuvenation or longer life. Related chromatin-program publications may overlap.
Bulletin of experimental biology and medicine 2004 · Journal publication
Review dates and the material assessed are listed with each publication below.
02 / HOW TO READ THE RESEARCH
Understanding the evidence
Human research
Human-derived serum and cells; no human efficacy trial established
Study methods
Cell, tissue and animal models; quantitative assay results linked
Independent replication
New citations are not automatically independent replication; shared programs and translated reports require cohort checks
Source access
Primary-publication records linked; full-text versus abstract review shown per source
Safety evidence
Reported tolerability is not proof of safety; uncommon harms and long-term outcomes remain unresolved
Open a topic for the evidence assessment.
More findings, background and history
What remains unclear
The available experimental studies leave human benefit and safety uncertain.
No human intervention report has been identified among the linked records; unclassified archival leads may remain. Several publications can describe the same participants.
Evidence belongs to the preparation actually studied. A tissue extract and a synthetic peptide can belong to the same research tradition without having equivalent effects or safety.
Liver: the molecular link
Ventvil → Livagen / KEDA
The 2020 Russian review discusses the liver complex and defined tetrapeptide together as separate experimental interventions.
Clinical evidence and limitations
The recovered review describes animal and cell models of fibrosis/hepatitis, not a human treatment trial.
Original model-specific papers and molecular characterization remain necessary. A shared research program is not proof of identical composition or effects.
PATENT RESEARCH / COLLECTION UPDATED 7 NOVEMBER 2026
Patents and claimed inventions
These 1 grouped records distinguish claimed molecules, uses, formulations and related chemistry. Patent disclosure does not establish clinical benefit or approval.
2006 · US7101854B2 · Livagen: KEDA molecular and hepatocyte-use claimsMolecule · 26.3 ± 1.8 → 21.7 ± 1.5
Reported findings
The patent reports changes in selected liver and immune markers during treatment.
Bilirubin
26.3 ± 1.8 → 21.7 ± 1.5Source table’s blanket units are questionable for different analytes, so no unit correction is invented
ALT
53.1 ± 4.7 → 40.8 ± 3.1Before/after; no established controlled treatment effect
Patent-defined substance or composition · Patent publication
Format: Original patent text and indexed metadata · Reviewed: Claims, selected reported findings and limitations reviewed; supporting experiments not comprehensively appraised.
Vladimir Khatskelevich Khavinson · US7101854B2 · patent family 20240745
The patent reports changes in selected liver and immune markers during treatment.
Results and tables
Reported patent results
Reported findings
The patent reports changes in selected liver and immune markers during treatment.
Livagen/KEDA patent example in 23 patients aged 32–53 with chronic persistent hepatitis; before/after, without a clear untreated comparator.
Results · 23-patient clinical description and Tables 4–5; unit limitations retained.
Measure
Result
Comparison, timing and statistics
Bilirubin
26.3 ± 1.8 → 21.7 ± 1.5
Source table’s blanket units are questionable for different analytes, so no unit correction is invented · p<0.05
ALT
53.1 ± 4.7 → 40.8 ± 3.1
Before/after; no established controlled treatment effect · p<0.05
Not marked significant in the table; selective positive reporting avoided
Uncontrolled marker changes do not prove liver regeneration, prevention of hepatocyte death or clinical disease modification. Published/patent versions may describe the same observations.
Livagen/KEDA patent example in 23 patients aged 32–53 with chronic persistent hepatitis; before/after, without a clear untreated comparator.
Source reviewed
Original patent publication accessed through Google Patents. Claims, selected reported findings and source limitations checked. The results section identifies the examples, tables and any numerical extraction gaps. No complete experimental audit, prosecution review or legal claim construction was performed.
Study limitations
Molecular identity and a patent use claim do not establish treatment of human liver disease.
Uncontrolled marker changes do not prove liver regeneration, prevention of hepatocyte death or clinical disease modification. Published/patent versions may describe the same observations.
Patents record claimed inventions and supporting disclosures. Publication or grant does not establish clinical efficacy, safety or marketing approval. Members of one patent family and related journal reports can describe the same experiments.
Status labels are Google Patents index snapshots for the displayed publication or application; each record lists the review date. Official registers and every national family member have not been independently checked. These labels do not establish freedom to operate.
Reviewed 2026-11-06.
Read the source ↗2003 · Effect of new peptide bioregulators livagen and epitalon on enkephalin-degrading enzymes in human serumEnkephalinase inhibition, IC50: Livagen 20 µM; Epitalon 500 µM
Livagen and Epitalon inhibited enkephalin breakdown in human serum, with IC50 values of 20 and 500 µM respectively. Neither bound the tested µ- or δ-opioid receptors.
Results and tables
Reported findings and study design
Livagen and Epitalon inhibited enkephalin breakdown in human serum, with IC50 values of 20 and 500 µM respectively. Neither bound the tested µ- or δ-opioid receptors.
Human-serum enzyme assay and rat-brain membrane receptor-binding assay.
Results · Primary-publication indexed abstract
Measure
Result
Comparison, timing and statistics
Enkephalinase inhibition, IC50
Livagen 20 µM; Epitalon 500 µM
Concentrations producing 50% inhibition in the serum assay
Opioid-receptor binding
No interaction detected at tested µ- or δ-receptors
Rat-brain membrane assay
These are laboratory concentrations and enzyme endpoints, not evidence of opioid-like clinical effects or an effective human dose.
Human-serum enzyme assay and rat-brain membrane receptor-binding assay.
Source reviewed
Original-publication metadata and indexed abstract checked in Europe PMC. No unavailable full-text figures inferred.
Study limitations
These are laboratory concentrations and enzyme endpoints, not evidence of opioid-like clinical effects or an effective human dose.
Reviewed 2026-11-01.
Read the source ↗2002 · Functional morphology of an organotypic liver culture exposed to the peptide livagenLiver-culture morphology: Improved structural preservation and cellular/intracellular regeneration markers reported; numerical size not supplied
Livagen supported liver-cell structural integrity and regeneration-related morphology in an organotypic culture. The abstract supplies no numerical effect size.
Results and tables
Reported findings and study design
Livagen supported liver-cell structural integrity and regeneration-related morphology in an organotypic culture. The abstract supplies no numerical effect size.
Organotypic liver culture; sample size and species not supplied in the indexed abstract.
Results · Primary-publication indexed abstract
Measure
Result
Comparison, timing and statistics
Liver-culture morphology
Improved structural preservation and cellular/intracellular regeneration markers reported; numerical size not supplied
A tissue-culture result; clinical liver function, fibrosis and patient outcomes were not tested.
Organotypic liver culture; sample size and species not supplied in the indexed abstract.
Source reviewed
Original-publication metadata and indexed abstract checked in Europe PMC. No unavailable full-text figures inferred.
Study limitations
A tissue-culture result; clinical liver function, fibrosis and patient outcomes were not tested.
Reviewed 2026-11-01.
Read the source ↗2001 · Rhythm of protein synthesis in cultures of hepatocytes from rats of different ages. Norm and effect of the peptide livagenProtein synthesis: Increased with Livagen; unchanged with Epitalon
Livagen increased protein synthesis in cultured rat liver cells, most strongly in cells from old animals. Epitalon did not change protein-synthesis intensity in this experiment.
Results and tables
Reported findings and study design
Livagen increased protein synthesis in cultured rat liver cells, most strongly in cells from old animals. Epitalon did not change protein-synthesis intensity in this experiment.
Cultured hepatocytes from rats aged 1–24 months.
Results · Primary-publication indexed abstract
Measure
Result
Comparison, timing and statistics
Protein synthesis
Increased with Livagen; unchanged with Epitalon
Cultured rat hepatocytes
Age range
1–24 months
The animals supplied cells; this was not a treatment trial in living rats or people.
Original-publication metadata and indexed abstract checked in Europe PMC. No unavailable full-text figures inferred.
Study limitations
The animals supplied cells; this was not a treatment trial in living rats or people.
Reviewed 2026-11-01.
Read the source ↗2004 · Effects of short peptides on lymphocyte chromatin in senile subjectsChromatin readouts: Ribosomal-gene activation and decondensation reported; no numerical treatment effect supplied
Khavinson VKh, Lezhava TA, Malinin VV · Bulletin of experimental biology and medicine 2004
Five short peptides increased ribosomal-gene activity and altered condensed chromatin in sampled leukocytes. Epitalon, Livagen and Prostamax changed chromosome-1 pericentromeric chromatin; Epitalon and Livagen also changed chromosome 9.
Results and tables
Reported findings and study design
Five short peptides increased ribosomal-gene activity and altered condensed chromatin in sampled leukocytes. Epitalon, Livagen and Prostamax changed chromosome-1 pericentromeric chromatin; Epitalon and Livagen also changed chromosome 9.
Leukocytes sampled from people aged 75–88 years and exposed to peptides in culture.
Results · Primary-publication indexed abstract
Measure
Result
Comparison, timing and statistics
Chromatin readouts
Ribosomal-gene activation and decondensation reported; no numerical treatment effect supplied
Donor ages
75–88 years
People donated cells; they were not treated in a clinical trial. Chromatin changes do not establish rejuvenation or longer life. Related chromatin-program publications may overlap.
Leukocytes sampled from people aged 75–88 years and exposed to peptides in culture.
Source reviewed
Original-publication metadata and indexed abstract checked in Europe PMC. No unavailable full-text figures inferred.
Study limitations
People donated cells; they were not treated in a clinical trial. Chromatin changes do not establish rejuvenation or longer life. Related chromatin-program publications may overlap.
Reviewed 2026-11-01.
Read the source ↗2002 · Effects of Livagen peptide on chromatin activation in lymphocytes from old people.
Khavinson VKh, Lezhava TA, Monaselidze JG, Dzhokhadze TA, Dvalishvili NA, Bablishvili NK, Ryadnova IY · Bulletin of experimental biology and medicine · PMID 12533768
Livagen altered chromatin organization and ribosomal-gene activity in donor-derived lymphocytes.
Population / setting
Cultured lymphocytes from older donors
Source reviewed
Primary citation and indexed abstract reviewed through Europe PMC. Full article not appraised.
Study limitations
Cells from human donors are not a human treatment trial; rejuvenation and liver benefit were not established.
Full methods, reporting completeness and independent replication remain to be appraised.
Reviewed 2026-10-05.
Read the source ↗2005 · [Effect of peptide Livagen on activity of digestive enzymes in gastrointestinal tract and non-digestive organs in rats of different ages].Intestinal glycyl-L-leucine dipeptidase activity in vitro: 50% reduction
Young and old rats; companion digestive-enzyme assays
Source reviewed
Primary citation and indexed abstract reviewed through Europe PMC. Full article not appraised.
Study limitations
Rat enzyme activity and in-vitro stability do not establish human absorption or clinical benefit.
Full methods, reporting completeness and independent replication remain to be appraised.
Reviewed 2026-10-05.
Read the source ↗2020 · The influence of polypeptide liver complex and tetrapeptide KEDA on organism physiological function in norm and age-related pathology
V. Kh. Khavinson, A. Yu. Solovyev, S. I. Tarnovskaya, N. S. Linkova · Biology Bulletin Reviews 3(6):451–455
Mechanistic review with a table of 15 short peptides on page 453. Tissue labels in the research map are the authors’ proposed targets, not established clinical indications.
Population / setting
Review of earlier research
Source reviewed
Author-hosted English PDF and its peptide table checked. Each cited experiment remains a separate appraisal task.
Study limitations
Source-linked does not mean a completed risk-of-bias review.
A review is not an independent clinical replication; proposed mechanisms do not establish efficacy or safety.