Dihexa

Dihexa was developed at Washington State University by Joseph Harding and Joseph Wright, published in 2013. It is a small, orally bioavailable peptidomimetic built on the angiotensin IV (Ang IV) scaffold, modified to resist peptidase degradation and enhance CNS penetration. Its primary mechanism — potentiation of HGF/MET signaling — is distinct from all other nootropic peptides.

In animal models of Alzheimer's dementia, Dihexa reversed cognitive impairment at doses 10 million times lower than BDNF, the gold standard benchmark. It promotes synaptogenesis (new synapse formation) rather than merely protecting existing synapses, making it theoretically capable of structural cognitive restoration rather than just preservation.

// HGF/MET SUPERAGONISM

Dihexa potentiates the binding of Hepatocyte Growth Factor (HGF) to its receptor c-MET, a receptor tyrosine kinase expressed broadly in neurons. HGF/MET signaling drives synaptogenesis, dendritic arborization, and neuronal survival — processes that are deficient in Alzheimer's disease and cognitive aging.

// SYNAPSE FORMATION

By amplifying HGF/MET downstream signaling (PI3K/Akt and MAPK/ERK), Dihexa significantly increases synaptic density in the hippocampus and prefrontal cortex — areas critical for memory formation and executive function. This structural remodeling is detectable by electron microscopy in treated animals.