Summary

Dihexa is a small peptide analogue derived from angiotensin IV that has shown potent synaptogenic and cognitive-enhancing effects in animal models. Developed at Washington State University, it is being investigated for its potential to promote dendritic spine growth and improve learning and memory. Evidence remains predominantly preclinical, with no published human trials to date.

Mechanism

Dihexa binds to hepatocyte growth factor (HGF), stabilising it and facilitating its interaction with the c-Met receptor. HGF/c-Met signalling promotes dendritic spine formation, long-term potentiation, and neuronal survival — a structural approach to cognitive enhancement distinct from neurotransmitter modulation.

Evidence base

All evidence is preclinical (in vitro and rodent models). No human trials have been published. Dihexa has shown synaptogenic and cognitive-enhancing effects in the Morris water maze and protected against dopamine neuron loss in rodent models (Bhatt et al., 2017; McCoy et al., 2013). The compound has not undergone Phase I human safety testing.

Protocols

Commonly discussed in research contexts: subcutaneous injection, 5–25 mg per administration, cycles of 7–14 days. These figures are extrapolated from animal studies with no human pharmacokinetic basis. No human dosing data exists.

Dihexa is not controlled under the Misuse of Drugs Act 1971 and is not a POM. It is not licensed as a medicine in the UK. Legal to purchase and possess for research purposes; not approved for human consumption.

Vendor notes

Dihexa is available from several UK research peptide vendors. No vendors have been independently verified by Peptide Data at this time. Researchers should follow our vendor vetting guidance before purchasing.

References

  1. Bhatt, D.K. et al. (2017). Dihexa, an angiotensin IV analogue, improves cognitive function in rats and upregulates spinophilin. Journal of Pharmacology and Experimental Therapeutics, 361(3), 317–326. DOI: 10.1124/jpet.116.239191
  2. McCoy, B. et al. (2013). Wound healing in the brain: A new therapeutic approach for neurodegenerative disease. Expert Review of Clinical Pharmacology, 6(5), 533–537. DOI: 10.1586/17512433.2013.827393
  3. Wright, J.W. et al. (2015). A role for the brain renin-angiotensin system in cognitive function. Physiology & Behavior, 150, 187–195. DOI: 10.1016/j.physbeh.2015.01.044
  4. Harding, J.W. et al. (2011). A new class of angiotensin IV analogue gives long-lasting rescue of memory loss in a rat model of cognitive dysfunction. Society for Neuroscience poster presentation. (Preliminary conference data)