Cortagen

Cortagen (Ala-Glu-Asp-Pro, also designated AEDP) is a synthetic tetrapeptide bioregulator identified as the primary active fraction of Cortexin, a polypeptide complex derived from bovine cerebral cortex tissue. The compound is associated with the Russian bioregulator peptide research program developed by Professor Vladimir Khavinson and colleagues at the St. Petersburg Institute of Bioregulation and Gerontology.

Note on nomenclature: "PDA" as a peptide designation is ambiguous. In the context of this entry, PDA is interpreted as referring to Cortagen (Ala-Glu-Asp-Pro), since this sequence matches the Ala-Glu-Asp-Pro tetrapeptide derived from Cortexin. Cortagen should not be confused with polydopamine (also abbreviated PDA in materials science contexts).

Cortagen is available as a research compound primarily in Russia and Eastern Europe. It is not approved by the FDA or EMA. Its research base is primarily composed of Russian-language preclinical studies.

Cortagen operates as a short-peptide bioregulator, a class of compounds theorized to act at the epigenetic and transcriptional level to restore gene expression patterns disrupted by aging, stress, or ischemic injury. The tetrapeptide sequence Ala-Glu-Asp-Pro is believed to interact with regulatory DNA sequences and nuclear proteins to influence chromatin organization and the expression of genes governing neuronal survival, antioxidant defense, and neurotrophic factor production.

At the cellular level, Cortagen has been shown to prevent excessive lipid peroxidation during ischemic stress and maintain superoxide dismutase (SOD) and catalase activity in brain tissue — hallmarks of antioxidant neuroprotection. It also stimulates neurotrophic factor production and promotes structural recovery of peripheral nerve tissue following traumatic injury, based on preclinical data.

The epigenetic mechanism — specifically, modulation of heterochromatin structure in aging neurons — distinguishes Cortagen from receptor-mediated peptides like Semax or Selank. This mode of action is consistent with other short Khavinson-class bioregulators (e.g., Epitalon, Thymalin) and positions Cortagen as a gene expression modulator rather than a receptor ligand.