Quick Comparison
| Cortagen | GHK-Cu | |
|---|---|---|
| Half-Life | 1-3 hours | Topical: variable (local effect) | Injectable: 1-2 hours |
| Typical Dosage | Oral/sublingual: 10-20 mg once daily. Injectable: 1-10 mg subcutaneous once daily. Typical course: 10-20 days, repeated two or three times yearly. Available in capsule form in some markets. | Topical: 1-2% serum or cream once or twice daily. Injectable: 1-2 mg subcutaneous once daily. Microneedling: applied topically immediately after microneedling for enhanced penetration. Typical courses run 4-12 weeks. |
| Administration | Oral, sublingual, or subcutaneous injection | Topical (serums, creams), subcutaneous injection, or microneedling |
| Research Papers | 1 papers | 27 papers |
| Categories |
Mechanism of Action
Cortagen
Cortagen (Ala-Glu-Asp-Pro) is a synthetic tetrapeptide belonging to the Khavinson family of peptide bioregulators — short peptides proposed to regulate gene expression in a tissue-specific manner. The bioregulator hypothesis, developed by Professor Vladimir Khavinson over decades of research at the St. Petersburg Institute of Bioregulation and Gerontology, proposes that short peptides (2-4 amino acids) can penetrate cell membranes and nuclear envelopes, interact directly with DNA in a sequence-specific manner, and modulate transcription of tissue-relevant genes.
Cortagen is specifically designed to target neurons of the cerebral cortex. According to the Khavinson model, the AEDP tetrapeptide sequence has complementarity to specific DNA sequences in gene promoter regions active in cortical neurons. Upon binding to these regulatory elements, Cortagen is proposed to modulate chromatin structure and transcription factor access, influencing the expression of genes involved in neuronal function, synaptic transmission, antioxidant defense, and protein synthesis. The tissue specificity — cortex rather than other brain regions or body tissues — is attributed to the unique chromatin accessibility and transcription factor environment in cortical neurons that determines which genes are available for regulation.
Preclinical studies from Russian research programs have reported that Cortagen treatment improves cognitive function, enhances learning and memory, and provides neuroprotection in models of cerebral ischemia and age-related cognitive decline. The proposed mechanism involves restoration of age-related declines in protein synthesis in cortical neurons, enhancement of antioxidant enzyme expression (SOD, catalase, GPx), and improved synaptic function through upregulation of synaptophysin and other synaptic proteins. It should be noted that the peptide bioregulator field remains controversial in Western pharmacology — while the Russian research program is extensive, the proposed direct DNA-binding mechanism has not been independently validated through the standard molecular biology methods expected in Western peer-reviewed literature.
GHK-Cu
GHK-Cu (glycyl-L-histidyl-L-lysine copper complex) is a naturally occurring tripeptide first isolated from human plasma in 1973 by Dr. Loren Pickart. Its copper-binding affinity is exceptionally high, and this copper chelation is central to its biological activity — the copper ion is coordinated by the histidine and lysine residues, creating a stable yet bioavailable copper delivery system.
The primary mechanism involves activation of copper-dependent enzymes critical for tissue structure and defense. Lysyl oxidase requires copper to catalyze the oxidative deamination of lysine and hydroxylysine residues in collagen and elastin precursors, forming the covalent cross-links (desmosine and isodesmosine) that give connective tissue its tensile strength and elasticity. Without adequate copper delivery, collagen fibers remain weak and poorly organized. Superoxide dismutase (Cu/Zn-SOD) uses the copper delivered by GHK-Cu for its antioxidant catalytic cycle, converting destructive superoxide radicals into hydrogen peroxide and oxygen.
Beyond copper delivery, GHK-Cu has remarkable gene-regulatory effects. Transcriptomic studies have shown it modulates the expression of over 4,000 human genes — approximately 6% of the genome. It upregulates genes involved in collagen synthesis (types I, III, V), elastin production, glycosaminoglycan synthesis, integrin and laminin expression, and growth factor production (TGF-β, VEGF, FGF). Simultaneously, it downregulates genes associated with inflammation, tissue destruction (matrix metalloproteinases), and fibrosis. In skin specifically, GHK-Cu stimulates dermal fibroblast proliferation, increases dermal thickness, improves skin density and firmness, and enhances wound contraction. It also promotes nerve outgrowth and blood vessel formation at wound sites. The breadth of its gene-regulatory activity suggests it acts as a master signaling molecule for tissue remodeling, essentially resetting gene expression patterns toward a younger, more regenerative profile.
Risks & Safety
Cortagen
Common
mild headache, temporary fatigue during initial use.
Serious
limited Western safety data, most evidence comes from Russian-language literature, no long-term data on repeated use.
Rare
allergic reactions.
GHK-Cu
Common
mild skin irritation, redness, bruising, injection site irritation.
Serious
theoretical risk of copper accumulation with long-term high doses; no long-term safety data for injectable use.
Rare
allergic reactions, contact dermatitis.
Full Profiles
Cortagen →
A short synthetic peptide (Ala-Glu-Asp-Pro) developed by the Khavinson Institute in Russia. Designed to support brain cortex function by modulating gene expression in brain cells. Part of the Khavinson peptide bioregulator family alongside Epithalon and Vilon. One of the few peptides specifically formulated for brain function optimization, available in both injectable and oral/sublingual forms.
GHK-Cu →
A naturally occurring copper-binding peptide found throughout the body; levels drop after age 20. The most studied cosmetic peptide, with proven effects on collagen production, skin renewal, wound healing, and antioxidant protection. It influences over 4,000 genes, shifting them toward a younger, more regenerative pattern. People use it for skin aging, wound healing, and anti-aging.