Cortagen

Cortagen is Ala-Glu-Asp-Pro, derived from the same fractionation work that produced the Cortexin brain extract. Russian preclinical studies report faster axon regrowth and restoration of conduction velocity in crushed or transected sciatic nerve, along with improved cortical electrical activity after experimental brain injury. The proposed mechanism blends the class-standard chromatin de-repression argument with more specific claims about neurotrophic factor expression and Schwann cell activity. Human use in Russia is mostly in neurology and rehabilitation settings, again without controlled published data in English.

Targets: Cerebral cortex neurons, Peripheral nerve axons, Neurotrophic factor expression

• · Intramuscular is the traditional route for this one in Russian practice; subcutaneous is what most Western users actually do.
• · Used as a maintenance format between injectable courses.

Work out your exact syringe units →

• commonInjection-site soreness— More noticeable intramuscularly.
• commonNo consistent systemic side effects reported— Very limited exposure data.
• uncommonMild headache— Reported anecdotally in the first days of a course.

• Pregnancy and breastfeeding - no data.
• Active CNS malignancy.

• synergypinealon — The conventional brain Cytogen pairing - cortex plus neuron.
• redundantcerebrolysin — Cerebrolysin is a far better-studied brain peptide preparation aimed at the same indications.
• redundantcerluten — Cerluten is the brain Cytomax covering the same claimed ground.

• · For a nerve injury, track something objective - grip strength, two-point discrimination, or nerve conduction studies if you have access.
• · No bloodwork is established.

Not approved for human use in the US, UK or EU; sold as a research chemical or as a supplement capsule in Russia and Eastern Europe.

• Khavinson & Malinin, Gerontological Aspects of Genome Peptide Regulation (Karger monograph) (review)
• Khavinson et al., peripheral nerve regeneration studies with cortical tetrapeptide (Bulletin of Experimental Biology and Medicine) (preclinical)

The proposed mechanism for the entire Khavinson bioregulator series is that these short peptides penetrate cell and nuclear membranes and interact directly with specific promoter regions of DNA in a sequence-selective way, modulating expression of tissue-appropriate genes. It needs saying plainly that this is asserted far more often than it is demonstrated, and that essentially all supporting work comes from a single research lineage that also developed and sells the compounds. There is real indexed work behind Cortagen specifically - a microarray study of gene expression changes in mouse heart, studies on sciatic nerve regeneration and delayed restoration of injured nerve function, and effects on interleukin-2 gene expression in splenocytes and hypothalamic structures. That is a genuine if modest experimental record, and it is more than most bioregulators have. What it is not is a demonstration of the sequence-specific DNA-binding mechanism in a way an independent laboratory has confirmed. The deeper problem is a chemical one that consumers rarely encounter: a tetrapeptide of common amino acids, taken orally, is degraded to Ala, Glu, Asp and Pro, and any biological effect then has to be explained by something that survived. The parenteral route at least puts intact peptide into circulation. The oral capsule format that most people actually buy has to clear a bar that nobody has shown it clears. Approach the mechanistic account here as a hypothesis with a long tradition and a commercial interest attached, not as established pharmacology.

The oral route is where the problems concentrate. Bioregulator capsules are the format most people buy, a free tetrapeptide has poor oral bioavailability by basic peptide chemistry, and no absorption study has been published for this compound. Anyone taking oral Cortagen may well be taking four amino acids. The injectable route at least delivers intact peptide, at the cost of needing to inject. Beyond that, the failure is evaluative rather than physical: this compound is essentially non-toxic in everything reported, it produces no acute effect, and the evidence base consists of open-label work from a single commercially interested lineage. That combination means a course will feel like it might be working and no amount of introspection will tell you whether it is. The other realistic issue is supply - exported bioregulator capsules are sold as supplements with correspondingly loose quality control, and the actual peptide content of a capsule is rarely independently verified.

1. 5 mgDays 1-10, injectable course — 5 mg once daily intramuscular, from a 10 mg vial reconstituted in 1-2 mL of saline or water for injection. It dissolves readily.
2. 10 mgDays 1-10, standard injectable course — 10 mg once daily intramuscular for 10 days is the standard Khavinson course. Courses are repeated every 4-6 months in the Russian pattern of use rather than run continuously.
3. 20 mgOral capsule course, 20-30 days — 10-20 mg once or twice daily, taken 10-15 minutes before food, for 20-30 days. This is the more common consumer format and the one whose bioavailability is most questionable - oral absorption of an intact free tetrapeptide is inherently poor and has never been demonstrated for this compound.

• Gene promoter regions (proposed direct sequence-specific DNA binding) — No binding constant has ever been published. The mechanism is proposed rather than characterised

  Claimed modulation of tissue-appropriate gene expression. A microarray study did document gene expression changes in mouse heart after Cortagen, which demonstrates an effect on transcription without demonstrating the proposed direct-binding mechanism.

• Peripheral nerve regeneration — Not receptor-defined

  Reported effects on sciatic nerve regeneration and on delayed restoration of injured nerve function in rats. The most concrete experimental claim for this specific peptide.

• Interleukin-2 gene expression — Not quantified

  Reported changes in IL-2 mRNA in splenocytes and in rat hypothalamic structures after short peptide administration. Part of a broader immune-modulation claim across the bioregulator series.

• Antioxidant enzyme expression — Not quantified

  Claimed increase in antioxidant enzyme activity. Reported within the same research lineage; not independently replicated.

Nothing acute. Effects, where claimed, appear over the course of a 10-20 day injectable course or a 20-30 day oral one rather than at any identifiable point. The nerve regeneration work specifically examined delayed effects, which is consistent with the transcriptional mechanism the series claims and inconsistent with anything you would feel. Courses are repeated two or three times a year in the standard Khavinson pattern. There is no published timecourse data of any kind because there is no pharmacokinetic study.

Standard Khavinson practice is to run tissue-specific bioregulators alongside the pineal peptide Epitalon as a combined course, and to pair brain-targeted peptides such as Pinealon with Cortagen in the same 10-30 day block. That is the tradition rather than an evidence-based protocol, and it is worth recognising that the practice of stacking multiple bioregulators originates with the group that sells them. Running Cortagen with Cortexin is duplication by the manufacturer's own framing - Cortagen is positioned as the synthetic tetrapeptide counterpart of the Cortexin extract - with the added consideration that Cortexin carries bovine protein allergen exposure that the synthetic peptide does not. If you are choosing between them on that basis alone, the synthetic one is the safer object. Whether either does anything is a separate question.

Against Cortexin, the extract it is derived from: Cortagen has the advantage of being a defined synthetic molecule with no bovine protein and no anaphylaxis risk, and the disadvantage of an even thinner clinical record. Neither has a randomised controlled trial. Against Epitalon and the rest of the Khavinson series: same evidential situation, same single research lineage, same asserted DNA-binding mechanism. If you find one convincing you will find them all convincing, and if you do not, the same applies. Against Cerebrolysin: Cerebrolysin has thousands of randomised patients and independent Cochrane scrutiny producing an ambiguous answer; Cortagen has open-label reports from its developers. Against Semax or Noopept, which are also Russian and also registered: those have published human comparative trials and identified mechanisms. Cortagen has neither, and the language used to market it is considerably more confident than the language used for either of them. That inversion - the weakest evidence dressed in the strongest claims - is the single most useful thing to notice about the bioregulator category.

$30–$120/month. Oral bioregulator capsules typically run 40-90 USD for a 20-30 day course, which is the format most consumers buy and the one with the weakest absorption argument. Injectable 10 mg vials from Russian sources run roughly 8-20 USD each, so a 10-day injectable course is 80-200 USD. Since courses are repeated only two or three times a year, the annualised cost is modest either way.

• ?The proposed sequence-specific DNA-binding mechanism has never been independently demonstrated outside the Khavinson research lineage.
• ?No pharmacokinetic data exists in any species - no tmax, half-life, bioavailability, distribution, clearance or protein binding.
• ?Oral bioavailability of an intact free tetrapeptide has not been demonstrated for this compound, and basic peptide chemistry argues against it.
• ?Whether any intact peptide crosses the blood-brain barrier has never been shown.
• ?No randomised controlled trial of Cortagen exists that I could locate.
• ?The tissue-specificity claim sits awkwardly with the finding that a cortex-derived peptide produces measurable gene expression changes in mouse heart.
• ?The reported benign safety profile comes from the same sources that report the efficacy, with no independent toxicology.
• ?The 10-day course length and 4-6 month repeat interval are convention across the whole bioregulator series rather than the result of any dose-finding study.
• ?The molecular weight of 430.4 Da is consistent with the Ala-Glu-Asp-Pro tetrapeptide but I did not verify it against a primary characterisation.
• ?Actual peptide content of exported consumer capsules is not independently verified by anyone.

• Effect of tetrapeptide cortagen on regeneration of sciatic nerve Turchaninova LN, Kolosova LI, Malinin VV, Moiseeva AB, Nozdrachev AD, Khavinson VK, Bulletin of Experimental Biology and Medicine, 2000 · PMID 11276314

  One of the more concrete experimental claims for Cortagen specifically - peripheral nerve regeneration in rats. From the developing group, as is essentially all of this literature.

• The delayed effect of cortagen on the restoration of injured nerve function Kolosova LI, Moiseeva AB, Turchaninova LN, Malinin VV, Polyakov EL, Nozdrachev AD, Khavinson VK, Doklady Biological Sciences, 2002 · PMID 12134478

  Follow-up on the nerve regeneration finding, examining the delayed rather than acute effect - which is consistent with the transcriptional mechanism the series claims.

• Elucidation of the effect of brain cortex tetrapeptide Cortagen on gene expression in mouse heart by microarray Anisimov SV, Khavinson VKh, Anisimov VN, Neuro Endocrinology Letters, 2004 · PMID 15159690

  The closest thing to direct support for a transcriptional mechanism - genome-wide expression changes in mouse heart after Cortagen. Note the tissue: a peptide claimed to be cortex-specific producing measurable changes in cardiac gene expression is an interesting result for the tissue-specificity claim, and not obviously in its favour.

• In vitro effect of short peptides on expression of interleukin-2 gene in splenocytes Kazakova TB, Barabanova SV, Khavinson VKh, Glushikhina MS, Parkhomenko EP, Malinin VV, Korneva EA, Bulletin of Experimental Biology and Medicine, 2002 · PMID 12447482

  Immune gene expression effects across the short peptide series. Relevant to the claim that these peptides act transcriptionally, and to the observation that the effects are not confined to the nominal target tissue.