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    §LongevityResearch protocol

    Cortagen.

    Cortagen dosage protocols are designed around this synthetic tetrapeptide (Ala-Glu-Asp-Pro) that belongs to the Khavinson bioregulator class, studied for its neuroprotective and neuroregenerative p...

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    Research Use Only. PeptiJournal supports private research documentation and calculation support. It does not provide medical advice, human-use directions, or claims of safety or effectiveness.

    Cited diluent3 mL

    Cited protocol example—review and confirm.

    Per-event reference amount by cited phase

    Reference syringe capacity

    Concentration
    6,666.667
    mcg/mL
    Per event
    1 mg
    7 events/week
    Vials projected
    3
    4 cited weeks

    Calculated volume reference

    0255075100

    15.0 units

    1mL syringe

    Cortagen
    15.0u(0.150 mL)
    Daily

    Cited protocol & reconstitution guide

    Source-backed reference fields by phase, including any volume fields authored in the cited guide.

    Weeks 1–2

    1000 mcg

    Units / volume15 units (0.15 mL)

    Weeks 3–4

    2000 mcg

    Units / volume30 units (0.30 mL)

    Overview

    Overview

    Cortagen dosage protocols are designed around this synthetic tetrapeptide (Ala-Glu-Asp-Pro) that belongs to the Khavinson bioregulator class, studied for its neuroprotective and neuroregenerative properties[1][2]. Research indicates Cortagen may support peripheral nerve regeneration, enhance cognitive function, reduce oxidative stress in neural tissues, and promote cellular repair mechanisms without significant adverse effects at therapeutic doses[3][4]. This educational protocol presents a once

    Category
    Longevity
    Routes
    subcutaneous

    Mechanism

    Cortagen

    Mechanism of action

    Mechanism of action

    Cortagen (Ala-Glu-Asp-Pro) is a synthetic tetrapeptide derived from amino acid analysis of the natural brain cortex preparation Cortexin [3] . It acts as a gene expression modulator and epigenetic regulator, influencing the synthesis of proteins involved in neuronal growth, differentiation, and stress resistance [6] [7] . Preclinical studies demonstrate that Cortagen can upregulate neurotrophic factors, reduce oxidative stress markers, and accelerate peripheral nerve regeneration—increasing nerve fiber growth rate and conduction velocity by 27–40% in injury models [1] . In chronic cerebral ischemia models, Cortagen improved behavioral recovery and protected against oxidative damage [2] .

    Key research findings
    • 01

      Animal model (rat): In sciatic-nerve transection/suture models, intramuscular Cortagen (research-reported at 10 ug/kg for 10 days) increased regenerating nerve-fiber growth rate by ~27% and conduction velocity by ~40%, with a separate report describing a delayed effect on restoration of injured-nerve function (Turchaninova et al., 2000, Bull Exp Biol Med, PMID 11276314; Kolosova et al., 2002, Dokl Biol Sci, DOI 10.1023/a:1016098302564). Rodent observations only; not established in humans.

    • 02

      Animal model (rat): Cortagen injections reduced lipid-peroxidation products and oxidative protein modification in serum and cerebral cortex (Kozina, 2007, Bull Exp Biol Med, DOI 10.1007/s10517-007-0230-8) and, in chronic cerebral-ischemia models, were associated with faster recovery of behavior and limited oxidative stress (Zarubina & Shabanov, 2011, Eksp Klin Farmakol, PMID 21476278; 2016, DOI 10.1007/s10517-016-3193-9). These are preclinical antioxidant-associated signals, not clinical evidence.

    • 03

      Animal model (mouse): A cDNA microarray of >15,000 transcripts found that a 5-day Cortagen course altered expression of ~110 genes in mouse heart, and separate in-vivo work showed modulation of hypothalamic IL-2 mRNA, supporting a gene-expression-modulating mechanism shared in part with related short peptides (Anisimov SV, Khavinson, Anisimov VN, 2004, Neuro Endocrinol Lett, PMID 15159690; Kazakova et al., 2005, Bull Exp Biol Med, DOI 10.1007/s10517-005-0388-x).

    • 04

      In vitro (rat organotypic culture): Cortagen showed tissue-specific stimulation of cerebral-cortex explant growth, the basis of the 'cytogen' tissue-specificity hypothesis, and activated IL-2 mRNA in cultured splenocytes more weakly than related peptides (Khavinson, 2001, Bull Exp Biol Med, DOI 10.1023/a:1013058701974; Kazakova et al., 2002, Bull Exp Biol Med, DOI 10.1023/a:1020210615148).

    • 05

      In vitro (ex vivo human lymphocytes, donors aged 75-88): Cortagen, alongside other short peptides, was reported to activate ribosomal genes and decondense age-condensed chromatin (deheterochromatinization), an epigenetic-aging readout in cultured cells, not a clinical outcome (Khavinson, Lezhava & Malinin, 2004, Bull Exp Biol Med, DOI 10.1023/b:bebm.0000024393.40560.05; Lezhava et al., 2023, Georgian Med News, PMID 37042594).

    • 06

      In vitro + animal model (null/weak results, included for balance): Cortagen produced no comitogenic effect on mouse thymocyte proliferation (Khavinson et al., 2002, Bull Exp Biol Med, DOI 10.1023/a:1019830308824) and, unlike the related peptide epithalon, did not alter immunity or hemostasis parameters in hypophysectomized or aged birds (Kuznik et al., 2008, Adv Gerontol, PMID 19432169); observed effects in research appear tissue- and context-dependent.

    Primary source: Based on PubMed-indexed literature, the research base for Cortagen (synthetic tetrapeptide Ala-Glu-Asp-Pro) is real but narrow and preclinical: roughly 15 indexed reports, overwhelmingly from a single Russian research lineage (Khavinson / St. Petersburg Institute of Bioregulation and Gerontology and collaborators), concentrated in Bulletin of Experimental Biology and Medicine and based mainly on rodent and in vitro/ex vivo models, with several reports in Russian and some null findings. No registered or controlled human efficacy trials were located and independent replication outside the originating group is limited, so research maturity remains low.

    Researched Effects

    Researched benefits

    Areas of active research and investigation. Results may vary and are based on preclinical or early clinical data.

    ✨

    Supports peripheral nerve regeneration with improved growth rate and conduction velocity in injury models[1].

    ✨

    Demonstrates neuroprotective effects in ischemia models by reducing lipid peroxidation and preserving antioxidant enzyme activity[2].

    ✨

    May enhance cognitive function and memory through promotion of synaptic plasticity and neurite outgrowth[4][5].

    ✨

    Shows gene expression modulation in cardiac and neural tissues with broad regulatory effects[3][6].

    Protocol Reference

    Protocol reference

    Research Use Only. PeptiJournal supports private research documentation and calculation support. It does not provide medical advice, human-use directions, or claims of safety or effectiveness.
    subcutaneous

    Commonly cited research range: 1–2 mg, daily.

    Reference figures reported in the research literature — not a dosing recommendation. For interactive vial math and scheduling, see the Calculator and Schedule tabs.

    Cited protocol & reconstitution guide

    Source-backed reference fields by phase, including any volume fields authored in the cited guide.

    Weeks 1–2

    1000 mcg

    Units / volume15 units (0.15 mL)

    Weeks 3–4

    2000 mcg

    Units / volume30 units (0.30 mL)

    Storage & Handling

    Storage requirements(typical for most peptides)

    ❄️
    Lyophilized (powder)
    -20°C (frozen)

    Can be stored for extended periods. Protect from moisture.

    🧊
    Reconstituted
    2-8°C (refrigerated)

    Store in refrigerator door. Never freeze after reconstitution.

    ⏱️
    Stability window
    28-30 days after reconstitution

    Label vials with reconstitution date. Discard if cloudy.

    Reconstitution steps

    1. 01🌡️Draw 3.0 mL bacteriostatic water with a sterile syringe.
    2. 02🧴Inject slowly down the vial wall; avoid foaming.
    3. 03💉Gently swirl/roll until dissolved (do not shake).
    4. 04💧Label and refrigerate at 2–8 °C (35.6–46.4 °F), protected from light.
    5. 05🔄Important: This guide is for educational purposes only and is not medical advice. For research use only. Not for human consumption.

    Additional storage notes

    Lyophilized

    Store at −20 °C (−4 °F) for long-term; 2–8 °C (35.6–46.4 °F) acceptable for short-term (weeks to months).

    Reconstituted

    Refrigerate at 2–8 °C (35.6–46.4 °F); use within 4 weeks and avoid freeze–thaw .

    Allow vials to reach room temperature before opening to reduce condensation uptake.

    Clinical Evidence

    Clinical evidence

    Preclinical research reports neuroregenerative and antioxidant activity; human data are limited.

    Based on PubMed-indexed literature, the research base for Cortagen (synthetic tetrapeptide Ala-Glu-Asp-Pro) is real but narrow and preclinical: roughly 15 indexed reports, overwhelmingly from a single Russian research lineage (Khavinson / St. Petersburg Institute of Bioregulation and Gerontology and collaborators), concentrated in Bulletin of Experimental Biology and Medicine and based mainly on rodent and in vitro/ex vivo models, with several reports in Russian and some null findings. No registered or controlled human efficacy trials were located and independent replication outside the originating group is limited, so research maturity remains low.

    1. 01Animal model (rat): In sciatic-nerve transection/suture models, intramuscular Cortagen (research-reported at 10 ug/kg for 10 days) increased regenerating nerve-fiber growth rate by ~27% and conduction velocity by ~40%, with a separate report describing a delayed effect on restoration of injured-nerve function (Turchaninova et al., 2000, Bull Exp Biol Med, PMID 11276314; Kolosova et al., 2002, Dokl Biol Sci, DOI 10.1023/a:1016098302564). Rodent observations only; not established in humans.
    2. 02Animal model (rat): Cortagen injections reduced lipid-peroxidation products and oxidative protein modification in serum and cerebral cortex (Kozina, 2007, Bull Exp Biol Med, DOI 10.1007/s10517-007-0230-8) and, in chronic cerebral-ischemia models, were associated with faster recovery of behavior and limited oxidative stress (Zarubina & Shabanov, 2011, Eksp Klin Farmakol, PMID 21476278; 2016, DOI 10.1007/s10517-016-3193-9). These are preclinical antioxidant-associated signals, not clinical evidence.
    3. 03Animal model (mouse): A cDNA microarray of >15,000 transcripts found that a 5-day Cortagen course altered expression of ~110 genes in mouse heart, and separate in-vivo work showed modulation of hypothalamic IL-2 mRNA, supporting a gene-expression-modulating mechanism shared in part with related short peptides (Anisimov SV, Khavinson, Anisimov VN, 2004, Neuro Endocrinol Lett, PMID 15159690; Kazakova et al., 2005, Bull Exp Biol Med, DOI 10.1007/s10517-005-0388-x).
    4. 04In vitro (rat organotypic culture): Cortagen showed tissue-specific stimulation of cerebral-cortex explant growth, the basis of the 'cytogen' tissue-specificity hypothesis, and activated IL-2 mRNA in cultured splenocytes more weakly than related peptides (Khavinson, 2001, Bull Exp Biol Med, DOI 10.1023/a:1013058701974; Kazakova et al., 2002, Bull Exp Biol Med, DOI 10.1023/a:1020210615148).
    5. 05In vitro (ex vivo human lymphocytes, donors aged 75-88): Cortagen, alongside other short peptides, was reported to activate ribosomal genes and decondense age-condensed chromatin (deheterochromatinization), an epigenetic-aging readout in cultured cells, not a clinical outcome (Khavinson, Lezhava & Malinin, 2004, Bull Exp Biol Med, DOI 10.1023/b:bebm.0000024393.40560.05; Lezhava et al., 2023, Georgian Med News, PMID 37042594).
    6. 06In vitro + animal model (null/weak results, included for balance): Cortagen produced no comitogenic effect on mouse thymocyte proliferation (Khavinson et al., 2002, Bull Exp Biol Med, DOI 10.1023/a:1019830308824) and, unlike the related peptide epithalon, did not alter immunity or hemostasis parameters in hypophysectomized or aged birds (Kuznik et al., 2008, Adv Gerontol, PMID 19432169); observed effects in research appear tissue- and context-dependent.

    Evidence maturity varies by compound; much peptide research is preclinical (in vitro or animal-model). Where human data are limited, findings should be read as research observations, not clinical conclusions.

    References

    Literature references

    Published research articles and sources related to Cortagen.

    1. 01
      PubMed — Effect of tetrapeptide cortagen on regeneration of sciatic nerve (nerve growth rate and conduction velocity improvements) View Source
    2. 02
      PubMed — Cortexin and cortagen as correcting agents in functional and metabolic disorders in the brain in chronic ischemia View Source
    3. 03
      PubMed (Neuroendocrinology Letters) — Elucidation of the effect of brain cortex tetrapeptide Cortagen on gene expression in mouse heart by microarray View Source
    4. 04
      PubMed (Biogerontology) — Peptide bioregulation of aging: results and prospects (lifespan extension and biomarker modulation) View Source
    5. 05
      Bentham Open (Open Neuropsychopharmacology Journal) — Modulatory effects of Cortexin and Cortagen on locomotor activity and anxiety-related behavior in mice View Source
    6. 06
      MDPI (Molecules) — Peptide Regulation of Gene Expression: A Systematic Review (epigenetic mechanisms) View Source
    7. 07
      Springer (Bulletin of Experimental Biology and Medicine) — Mechanisms Underlying Geroprotective Effects of Peptides View Source
    8. 08
      MedlinePlus — Subcutaneous (SQ) injections: technique, site rotation, and best practices View Source
    9. 09
      CDC (Subcut Injection PDF) — Vaccine Administration: Subcutaneous (SUBCUT) Injection technique and guidance View Source
    10. 10
      Bachem — Handling and Storage Guidelines for Peptides (stability and storage conditions) View Source
    11. 11
      MDPI (International Journal of Molecular Sciences) — Short Peptides Protect Fibroblast-Derived Induced Neurons from Age-Related Changes View Source
    12. 12
      Wikipedia — Cortagen (tetrapeptide overview and background) View Source
    13. 13
      Pure Lab Peptides — Cortagen (20 mg) product page (quality and batch documentation) View Source
    Search PubMed for Cortagen

    Observed Effects

    Observed effects in cited research

    Reported
    • Generally well tolerated with no significant adverse effects observed at therapeutic doses in animal studies[5].
    • Occasional mild injection-site reactions (redness/itch) may occur with subcutaneous administration.

    Research Considerations

    Research considerations

    Research Use Only - not for human or veterinary therapeutic use. Current evidence is limited to in vitro and/or animal-model research; human data are minimal or absent. Consult a licensed healthcare professional for any clinical decisions.

    Factors noted in the research literature; not patient-specific medical advice.

    Regulatory Status

    Regulatory status

    RUO

    Research Use Only. PeptiJournal supports private research documentation and calculation support. It does not provide medical advice, human-use directions, or claims of safety or effectiveness.

    Comparisons

    Comparisons

    CompoundMechanismRouteStatus
    CortagenthisA synthetic tetrapeptide (Ala-Glu-Asp-Pro) of the Khavinson bioregulator class studied for neuroprotective and neuroregenerative activity, including peripheral nerve repair.subcutaneousInvestigational / RUO
    Epitalon (Epithalon)A synthetic tetrapeptide (Ala-Glu-Asp-Gly) studied for activation of telomerase and modulation of pineal/melatonin and circadian pathways, of interest in geroprotection research.subcutaneousInvestigational / RUO
    FOXO4-DRIA D-retro-inverso peptide designed to disrupt the FOXO4-p53 interaction in senescent cells, releasing p53 to selectively induce apoptosis of senescent cells (a senolytic mechanism).subcutaneousInvestigational / RUO
    GlutathioneAn endogenous tripeptide (gamma-L-glutamyl-L-cysteinyl-glycine) functioning as a major intracellular antioxidant and redox buffer, supporting phase-II detoxification conjugation and neutralization of reactive oxygen species.subcutaneousInvestigational / RUO
    LivagenA synthetic tetrapeptide bioregulator (Lys-Glu-Asp-Ala) studied for peptidase modulation and epigenetic/chromatin effects (e.g., heterochromatin decondensation) in aging cell models.subcutaneousInvestigational / RUO
    DSIPA naturally occurring nonapeptide studied for influence on sleep architecture and hypothalamic-pituitary-adrenal (stress-axis) modulation; its precise receptor targets remain incompletely characterized.subcutaneousInvestigational / RUO
    GHK-CuStimulates collagen and glycosaminoglycan synthesis, promotes angiogenesis, and acts as antioxidant and anti-inflammatory agent.subcutaneous, topicalInvestigational / RUO

    Attributes shown for research comparison only; not a statement of efficacy or therapeutic equivalence.

    FAQ

    Frequently asked questions

    Research-use notice

    Research Use Only. This educational content and calculation support is intended for private research documentation. It does not provide medical advice, human-use directions, or claims of safety or effectiveness.

    Cited guide source: View source

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