Dihexa

Dihexa (N-hexanoic-Tyr-Ile-(6) aminohexanoic amide) is a synthetic oligopeptide derived from angiotensin IV, developed at Washington State University by Dr. Joseph Harding's research group. Dihexa has generated extraordinary interest in the cognitive research community based on a single defining characteristic: it is approximately 10 million times more potent than BDNF at promoting new synapse formation. This astonishing potency, measured by its ability to drive dendritic spine formation in hippocampal neuron cultures at femtomolar (10^-15 M) concentrations, makes Dihexa the most potent synaptogenic compound ever identified in the published literature.

Dihexa exerts its effects by binding to hepatocyte growth factor (HGF) and potentiating its interaction with the c-Met receptor. The HGF/c-Met pathway is a key driver of synaptogenesis, neuronal survival, and neurite outgrowth in the central nervous system. At sub-picomolar concentrations, Dihexa enhances HGF-mediated dendritic spine formation — the structural basis of synaptic connections. More spines mean more potential synapses, and more synapses mean greater cognitive bandwidth for learning, memory consolidation, and information processing. Dihexa also demonstrates neuroprotective effects: it protects against scopolamine-induced amnesia, improves performance in spatial memory tasks, and preserves cognitive function in models of neurodegeneration.

Research from the Harding laboratory and subsequent investigations demonstrate that Dihexa reverses cognitive deficits in aged animal models, improves spatial learning and memory consolidation, and promotes the formation of new functional neural connections. The compound's ability to cross the blood-brain barrier after peripheral administration (both oral and subcutaneous) distinguishes it from many neuroprotective compounds that require direct CNS delivery. However, the extreme potency of Dihexa also demands caution: uncontrolled synaptogenesis could theoretically have unpredictable effects on neural circuit organization, and long-term safety data remain limited.

Dihexa is suited for advanced researchers investigating synaptogenesis, cognitive repair, neurodegenerative processes, and the HGF/c-Met signaling axis. Given its extreme potency, precise dosing and careful protocol design are essential.

Reconstitute the 10mg vial with 2ml bacteriostatic water (yielding 5mg/ml). Dihexa can be administered subcutaneously, orally (dissolved in solution), or intranasally. Typical research dosing ranges from 10-40mg per day orally or 5-20mg subcutaneously — the oral bioavailability is sufficient for many research applications. Despite its femtomolar in vitro potency, in vivo dosing requires milligram quantities due to distribution, metabolism, and blood-brain barrier transit. Store at 2-8C after reconstitution. Dihexa has a half-life of approximately 2-4 hours. Given the limited long-term safety data, most research protocols are limited to 4-8 weeks.

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## Longevity & Anti-Aging