Testagen

Overview

Testagen is a synthetic tetrapeptide (Lys-Glu-Asp-Gly) from the Khavinson bioregulator series, studied for potential effects on testicular function, Leydig cell signaling, and age-related changes in gonadal hormone pathways.

Mechanism of Action

Testagen is proposed to modulate gene expression in Leydig cells, influencing StAR (steroidogenic acute regulatory protein) and CYP11A1, which catalyze rate-limiting steps of testosterone production. The Lys-Glu-Asp-Gly sequence may interact with specific DNA promoter regions per the Khavinson model.

Research Summary

Preclinical studies in aged male rats showed increased steroidogenesis gene expression and partial normalization of Leydig cell morphology (Khavinson et al., Bulletin of Experimental Biology and Medicine, 2014). In vitro Leydig cell cultures showed upregulated StAR protein and increased testosterone output. No Western-framework clinical trials conducted.

Dosing Information

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

• Peptide Regulation of Cell Differentiation (2020)