Neuropeptide analogues studied for cognition
This group brings together peptides derived from, or modelled on, natural neuropeptides and brain proteins that have been studied in memory, mood, sleep or brain-injury research. Their starting points differ widely: fragments or analogues of ACTH, tuftsin, angiotensin IV, ciliary neurotrophic factor and the sortilin propeptide, plus a porcine brain extract and a sleep-linked nonapeptide. Proposed mechanisms include changes in BDNF, GABA binding and potassium-channel activity, and none is settled. Cerebrolysin has the most human trial data; for the others, human data are small, non-blinded or absent.
How the members differ
- Semax is an ACTH(4-10) analogue linked to BDNF in rat brain, and Selank is a tuftsin analogue reported to modulate GABA binding; both are registered in Russia.
- Cerebrolysin is a porcine brain-derived peptide mixture whose individual active components are not defined.
- Dihexa (from angiotensin IV), P021 (from CNTF) and PE-22-28 (a sortilin propeptide fragment that blocks the TREK-1 channel) have only animal and cell data.
- DSIP was named for the slow-wave sleep it was proposed to promote, but no gene, protein or receptor for it has been isolated.
Compounds in this group
CerebrolysinHuman trial evidence · Approved outside the USCerebrolysin is a porcine brain-derived preparation of low-molecular-weight peptides and amino acids given by intravenous infusion or injection. It is authorised in Austria and used in Russia, Eastern Europe, China and other Asian countries for supportive treatment after stroke and head injury and in dementia, but it is not approved by the FDA. Randomized trials and Cochrane reviews report mixed results, including no clear effect on death after acute ischaemic stroke; this entry summarizes them for research reference only.
SemaxLimited human data · Approved outside the USSemax is a synthetic ACTH-fragment analogue developed in Russia and studied in rodent and cell models of neuroprotection and in small Russian clinical studies of stroke. It is reported to be registered as a drug in Russia but is not FDA-approved.
SelankLimited human data · Approved outside the USSelank is a synthetic heptapeptide analogue of tuftsin, studied in rodents and cell membranes for effects on GABAergic and opioid-related signaling. Small Russian-language clinical studies exist, and it is reported to be registered as a drug in Russia but not in the United States.
DSIPLimited human data · Not approved — research use onlyDSIP is a naturally occurring neuropeptide first isolated from rabbit brain, investigated in sleep, stress and neuroendocrine research.
DihexaPreclinical research · Not approved — research use onlyA small angiotensin IV-derived peptide analog investigated in animal and cell models of synaptic connectivity and neurotrophic signaling.
P-21Preclinical research · Not approved — research use onlyP-21 is a synthetic peptide derived from the neurotrophic factor CNTF, studied in preclinical research on neurogenesis and neuronal plasticity.
PE-22-28Preclinical research · Not approved — research use onlyPE-22-28 is a short synthetic peptide reported as a spadin-related fragment, investigated in neuronal ion channel and mood-related animal models.
Compare Cerebrolysin, Semax, Selank side by side
For research use only. Not for human or veterinary use. Not a drug, food, or dietary supplement. Mechanism descriptions summarize published research and are not claims of effect in people.