Dihexa

Also known as: N-hexanoic-Tyr-Ile-(6)-aminohexanoic amide, PNB-0408, angiotensin IV analog

Wellness

In plain English

Dihexa is an experimental compound derived from a fragment of angiotensin (a blood-pressure hormone) that was engineered to enter the brain and encourage new connections between nerve cells. In laboratory and animal models it strongly promotes synapse formation and improved memory, which is why it is marketed for cognition. However, there are no completed human trials, it is not FDA-approved, and there are theoretical safety concerns because it acts through a growth-factor pathway (HGF/c-Met) that is also involved in cancer.

The science

Dihexa is a small, orally active, blood-brain-barrier-penetrant angiotensin IV analog. Its procognitive and synaptogenic effects are dependent on activation of the hepatocyte growth factor (HGF)/c-Met receptor system, augmenting dendritic spine and synapse formation (Benoist et al., 2014; Wright & Harding, 2015). It reversed cognitive deficits in preclinical Alzheimer's and Parkinson's models at very low doses. All evidence is preclinical; there are no published human clinical trials, and because c-Met signaling is implicated in tumor growth, systemic long-term safety is unestablished. It is not FDA-approved and is sold as a research chemical.

References

• Benoist CC et al., J Pharmacol Exp Ther 2014 (HGF/c-Met-dependent synaptogenesis)
• Wright JW, Harding JW, Prog Neurobiol 2015 (angiotensin IV analogs for Alzheimer's/Parkinson's)