Testagen
Also known as Lys-Glu-Asp-Gly, testicular bioregulator, testis bioregulator
Testagen is a tetrapeptide (Lys-Glu-Asp-Gly) bioregulator from Khavinson's series that targets testicular tissue — specifically Leydig cells responsible for testosterone production. By restoring gene expression in testicular cells, it can help normalize testosterone levels, improve sperm quality, and support male reproductive health without directly injecting exogenous hormones.
How it works
Tetrapeptide that penetrates Leydig cell nuclei and interacts with chromatin, normalizing gene expression in testosterone-producing cells. Stimulates steroidogenesis at the cellular level, potentially increasing LH receptor expression and testosterone synthesis without exogenous hormone supplementation.
Benefits
- Stimulates testosterone production by restoring Leydig cell function
- Improves sperm quality and motility
- Supports male reproductive health and fertility
- Non-hormonal approach to testosterone optimization
- Anti-aging effects on testicular tissue
- May improve libido and sexual performance
- Restores HPT axis function
Dosing
100–500 mcg · Once daily
Typical course: 100–500mcg/day SubQ for 10–30 days. Some protocols use sublingual. Course-based — not chronic.
Ranges reflect commonly cited research protocols, not a prescription. Dose with a licensed provider.
Reconstitution
25mg vial with 2–5mL BAC water. Refrigerate, use within 30 days.
Helix’s free reconstitution calculator gives you the exact draw volume → get the app
Common stacks
Reported side effects
- Generally well tolerated
- Injection site irritation
- Limited long-term human data outside Russia
Who it’s for
Men with low testosterone, hypogonadism, reduced fertility, or seeking non-hormonal testosterone support. Men on TRT who want to preserve natural production. Advanced users seeking HPTA restoration.
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