Angiotensin (1-7) vs Testagen

Binds Mas receptor (MasR), activating nitric oxide synthase and reducing oxidative stress. Opposes TGF-β and angiotensin II signaling to reduce fibrosis. Enhances insulin sensitivity and provides cardiovascular protection.

Angiotensin-(1-7) [Ang-(1-7)] is an endogenous heptapeptide hormone generated primarily through cleavage of angiotensin II by ACE2, functioning as a counter-regulatory arm of the renin-angiotensin system (RAS) by binding the Mas receptor to promote vasodilation, anti-fibrotic, anti-inflammatory, and cardioprotective effects that oppose the vasoconstrictive actions of angiotensin II. Ang-(1-7) acts through the ACE2/Mas receptor axis to reduce oxidative stress, attenuate NF-kB-mediated inflammation, and suppress TGF-beta fibrosis signaling; the ACE2/Ang-(1-7)/Mas axis has emerged as a key regulatory pathway in cardiovascular and metabolic disease, and gained renewed research attention given ACE2's role as the SARS-CoV-2 entry receptor. A Phase 1-2 randomized clinical trial of Ang-(1-7) infusion in COVID-19 ICU patients reported preliminary safety, tolerability, and dose-response data, providing the primary indexed human pharmacokinetic evidence; broader cardiovascular protective applications are supported by preclinical data but have not been established by completed Phase 3 trials. Ang-(1-7) has no FDA approval and no approved therapeutic indication in any jurisdiction; it is an endogenous peptide under active clinical investigation as a candidate for cardiovascular, metabolic, and inflammatory conditions, with emerging human safety data but an incomplete evidence base for any specific approved clinical use.

Khavinson-class tetrapeptide bioregulator derived from testicular tissue; proposed to modulate gene expression in Leydig and Sertoli cells; investigated for age-related testicular function decline

Testagen is a synthetic tetrapeptide and Khavinson-class peptide bioregulator derived from testicular tissue, investigated for regulatory effects on testicular cell function and age-related reproductive hormone decline. Like other Khavinson-class bioregulators, testagen is proposed to act as a short regulatory peptide that modulates gene expression in target organ cells — in this case, testicular Leydig cells responsible for testosterone synthesis and Sertoli cells that support spermatogenesis. The Khavinson bioregulator model posits that short peptides derived from specific tissues preferentially interact with chromatin regulatory elements in homologous tissues, restoring expression of age-downregulated genes and partially reversing organ-level functional decline associated with aging. Research interest in testagen centers on age-associated decline in testicular function, including reduced Leydig cell activity and the associated decline in testosterone biosynthesis that characterizes male aging. Preclinical studies have examined testagen-class peptides for effects on reproductive hormone levels, testicular histomorphology, and markers of gonadal function in aged animal models. Testagen is part of the broader Khavinson bioregulator research program that has also characterized thymalin (thymus), cortagen (cardiovascular/neural), cartalax (cartilage), and pinealon (pineal gland) as organ-specific regulatory peptides. Testagen benefits investigated in preclinical research include support for testosterone biosynthesis pathways, maintenance of Leydig cell populations, and preservation of testicular tissue architecture with aging. These effects are proposed to occur through epigenetic regulatory mechanisms rather than direct hormonal supplementation, distinguishing bioregulator peptides from exogenous testosterone replacement. Testagen is classified as a research compound with no regulatory approval in any jurisdiction. No human clinical trials have established safety or efficacy for testicular support, testosterone augmentation, or reproductive function endpoints. Research protocols have examined testagen primarily via subcutaneous injection, with oral delivery also studied in bioregulator research contexts.