Overview
Testagen is a synthetic tetrapeptide bioregulator (Lys-Glu-Asp-Gly, KEDG) developed by Professor Vladimir Khavinson, targeting testicular tissue and the male reproductive axis. It is studied for its ability to support testosterone biosynthesis, Leydig cell function, and hormonal balance in aging men, with proposed applications in age-related male hypogonadism research.
Mechanism of action
Testagen penetrates both cell and nuclear membranes in testicular and hypothalamic-pituitary target tissues, interacting directly with DNA promoter regions of genes involved in steroidogenesis and gonadal function. It is proposed to stimulate Leydig cell activity by upregulating transcription of enzymes in the testosterone biosynthetic pathway (CYP11A1, 3β-HSD, CYP17A1). Testagen influences both the hypothalamic-pituitary-gonadal (HPG) axis controlling testosterone production and the hypothalamic-pituitary-thyroid (HPT) axis governing metabolic hormones. Like other Khavinson bioregulators, its tissue specificity arises from DNA sequence recognition patterns in the target organ. In aging testicular tissue, the peptide is proposed to reverse age-related epigenetic silencing of steroidogenic gene promoters.
Dosing protocols
| Purpose | Route | Dosage | Frequency | Notes |
|---|---|---|---|---|
| male hormonal research | subcutaneous | 0.1–0.5 mg | daily for 10–20 days | Standard Khavinson protocol: 10-day injection cycles, 2–4 times per year. |
| oral research use | oral | 1–2 mg | daily | Some researchers use oral or sublingual routes; bioavailability data not established. |
Dosing information is for educational purposes only. Consult a qualified healthcare professional before using any peptide.
Research summary
Russian research from Khavinson's group demonstrates Testagen's effects on testosterone pathway gene expression in aged testicular tissue models, with animal studies showing improved Leydig cell function and testosterone synthesis. Human evidence is limited to observational data from Russian clinical programs in aging men. The research base does not include randomized placebo-controlled trials meeting Western standards. Evidence of benefit in age-related male hypogonadism remains preliminary; no head-to-head comparisons with testosterone replacement therapy have been published.
Side effects
Side effects vary by individual. This is not an exhaustive list. Report unusual symptoms to a healthcare professional.
Common stacks
Peptides commonly paired with Testagen for synergistic effects.
Legal status
Not FDA-approved. Developed and studied in Russia; commercially sold as a cytogen bioregulator supplement. Available in Western markets as a research chemical. Not approved for therapeutic human use outside Russia.
Where to get it
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