Cortexin vs VIP

Polypeptide bioregulator from bovine cortex; modulates neurotransmitter activity; activates GABA and dopamine systems; reduces excitotoxicity; stimulates neuronal repair

Cortexin is a polypeptide bioregulator derived from porcine cerebral cortex, used clinically in Russia and Eastern Europe as a neuroprotective and nootropic agent for stroke, traumatic brain injury, and chronic cerebrovascular disorders. It contains a complex mixture of tissue-specific neuropeptides, amino acids, and microelements proposed to support neuronal survival, reduce excitotoxic damage, and promote neurotrophic factor expression in injured brain tissue. Russian clinical trials have examined cortexin in acute ischemic stroke rehabilitation and other neurological conditions, with results suggesting potential benefit in functional recovery, though studies are predominantly published in Russian-language journals with limited methodological transparency by international standards. Cortexin is not FDA-approved; it is a licensed prescription drug in Russia and several post-Soviet states, where it has regulatory approval for neurological indications. Cortexin administration: in clinical settings where it is approved, cortexin is administered by intramuscular injection, typically as a 10 mg dose reconstituted in saline or procaine. Clinical courses in Russian practice involve daily injections over 10-day cycles, repeated 1–2 times per year for chronic neurological conditions. This administration pattern is common to several Russian polypeptide bioregulators, including cerebrolysin — another porcine-derived peptide mixture with a broader international clinical trial dataset — and cortagen, a cardiac-focus bioregulator from the same pharmacological class. Cortexin is the cerebral-cortex-specific member of this class; cortagen targets cardiovascular tissue, and thymalin targets thymic/immune tissue. Provider availability for cortexin outside Russia is limited compared to peptides with international regulatory approvals; it is occasionally carried by compounding pharmacies and specialized nootropic suppliers. The PeptideBase cognitive peptides directory lists verified providers who carry neuroprotective peptide compounds.

Pleiotropic neuropeptide binding VPAC1/VPAC2 receptors; suppresses neuroinflammation, regulates circadian rhythm via SCN, modulates immune response

Vasoactive intestinal peptide (VIP) is a 28-amino-acid neuropeptide widely expressed in the central and peripheral nervous system that acts through VPAC1 and VPAC2 receptors to regulate neuroinflammation, circadian timing, immune modulation, and neurotransmitter release. VIP exerts potent anti-inflammatory effects by suppressing pro-inflammatory cytokine production in activated microglia and macrophages, and has been proposed as a therapeutic target for neuroinflammatory conditions including Alzheimer's disease, given its ability to shift microglial activation toward neuroprotective phenotypes. In vitro studies demonstrate that VIP significantly reduces inflammatory injury markers in microglial models exposed to neurotoxic stimuli, and preclinical data support VPAC receptor signaling as a mechanism for maintaining cognitive function under inflammatory conditions. VIP has no standalone FDA approval for neurological indications; research into exogenous VIP administration for neuroinflammatory and cognitive applications remains in early preclinical stages with no human clinical trials completed. VIP peptide therapy: CIRS, POTS, and mast cell contexts VIP has attracted clinical research interest beyond classical neurological applications. In the context of Chronic Inflammatory Response Syndrome (CIRS) — a condition proposed to arise from dysregulated innate immune response following biotoxin exposure — VIP nasal spray (Aviptadil) was included in the Shoemaker Protocol for its proposed ability to reduce neuroinflammatory cytokine activity and restore VIP deficiency observed in some CIRS patient cohorts. Published research by Shoemaker and colleagues documents VIP receptor abnormalities in CIRS, and observational data suggests intranasal VIP administration may partially restore inflammatory markers in this population; this work has not been replicated in large randomised controlled trials and remains within specialist functional medicine contexts. VIP and pulmonary/vascular research: Aviptadil (synthetic VIP) received FDA Breakthrough Therapy Designation for acute respiratory distress syndrome (ARDS) and was studied in COVID-19-related acute lung injury for its ability to reduce cytokine storm and preserve alveolar epithelial cells via VPAC1 receptor activation. Phase 2 data showed improvements in respiratory outcomes vs placebo in COVID-19 ARDS, though Phase 3 data was mixed. VIP is also proposed as a therapeutic target in pulmonary arterial hypertension given its vasodilatory and anti-proliferative effects on pulmonary vasculature. Injectable VIP for pulmonary vascular applications and intranasal VIP for neuroinflammatory conditions represent the most clinically developed research tracks for this compound.