Testagen

Overview

Testagen is a synthetic tetrapeptide (Lys-Glu-Asp-Gly / KEDG) from the Khavinson bioregulator series, claimed to target testicular tissue. Not FDA-approved. Evidence base is extremely thin, with essentially no independently replicated or peer-reviewed support for the advertised reproductive or endocrine benefits in humans.

Mechanism of Action

Proposed mechanism per the Khavinson model: the peptide penetrates cell cytoplasm and nucleus and preferentially binds CAG-containing DNA sequences in vitro. Specific effects on Leydig-cell StAR or CYP11A1 expression remain hypothetical and are not supported by replicated peer-reviewed studies.

Research Summary

Evidence is extremely limited. Fedoreyeva et al. (Biochemistry [Moscow], 2011; PMID 22117547) — from Khavinson-group collaborators — showed that fluorescently labeled Lys-Glu-Asp-Gly (testagen) penetrated HeLa-cell cytoplasm and nucleus and bound CAG-containing deoxyribooligonucleotides in vitro. No replicated Leydig-cell, animal, or human clinical-trial data has been published in indexed peer-reviewed literature. Reproductive or steroidogenic benefits in humans have not been demonstrated.

Vendors selling Testagen

Scored vendors carrying Testagen, ranked by trust grade. Grades are computed from indexed Certificates of Analysis. Full $/mg pricing is on the comparison page.

Reported Side Effects

• Limited human safety data
• Injection site irritation (preclinical)
• No significant adverse effects in published preclinical studies
• Potential hormonal fluctuation with repeated dosing (theoretical)

Research References

• Penetration of short fluorescence-labeled peptides into the nucleus in HeLa cells and in vitro specific interaction with DNA (Fedoreyeva, Kireev, Khavinson, Vanyushin) (2011)

Frequently asked questions

Has Testagen been independently lab-tested?

Disclosed Labs has collected 16 Certificates of Analysis (COA) for Testagen from 6 independent testing labs. 9 vendors have submitted material for testing. Products average 99.5% tested purity across the corpus. Full testing data is available at https://www.disclosedlabs.com/peptides/testagen/testing.

What is the average purity of Testagen on the market?

Based on 16 COAs analyzed by Disclosed Labs, Testagen products average 99.5% (±0.8%) tested purity. Individual vendor results vary; see per-vendor COA data at https://www.disclosedlabs.com/peptides/testagen/coas.

Where can researchers source Testagen?

7 vendors with Disclosed Labs trust grades currently list Testagen, including Glacier Aminos, OROS Research, Skye Peptides. Compare live prices and lab-verified COAs at https://www.disclosedlabs.com/prices/testagen.

How does Testagen work?

Proposed mechanism per the Khavinson model: the peptide penetrates cell cytoplasm and nucleus and preferentially binds CAG-containing DNA sequences in vitro. Specific effects on Leydig-cell StAR or CYP11A1 expression remain hypothetical and are not supported by replicated peer-reviewed studies.

What does the research say about Testagen?

Evidence is extremely limited. Fedoreyeva et al. (Biochemistry [Moscow], 2011; PMID 22117547) — from Khavinson-group collaborators — showed that fluorescently labeled Lys-Glu-Asp-Gly (testagen) penetrated HeLa-cell cytoplasm and nucleus and bound CAG-containing deoxyribooligonucleotides in vitro. No replicated Leydig-cell, animal, or human clinical-trial data has been published in indexed peer-reviewed literature. Reproductive or steroidogenic benefits in humans have not been demonstrated.