Dihexa Peptide: HGF/c-Met Signaling and Synaptogenesis Research
Dihexa is a metabolically stabilized angiotensin IV analog studied as a potentiator of HGF/c-Met signaling in the brain. This research-use-only reference explains what Dihexa is, how it engages the hepatocyte growth factor pathway, the spinogenesis and synaptogenesis it drives in hippocampal models, its reported potency, and the important caveats in its evidence base.
Research-use-only disclaimer: Dihexa supplied as a research chemical is intended strictly for in-vitro and laboratory research use and is not intended for human or veterinary use in that context. Every finding below is drawn from cell-culture or animal models and is described in hedged, mechanistic terms. Nothing here is medical advice.
TL;DR
Dihexa (N-hexanoic-Tyr-Ile-(6) aminohexanoic amide) is a metabolically stabilized angiotensin IV analog from Washington State University. It binds HGF and potentiates signaling through the c-Met receptor, inducing c-Met phosphorylation and hippocampal spinogenesis and synaptogenesis in research models; those effects were blocked by an HGF antagonist and c-Met knockdown. Note: a key study carries a journal Notice of Concern. Research use only.
Identity: angiotensin IV analog, N-hexanoic-Tyr-Ile-(6) aminohexanoic amide; orally active, BBB-permeable.
Mechanism: binds HGF and potentiates c-Met signaling; induces c-Met phosphorylation.
Effect: hippocampal spinogenesis and synaptogenesis, blocked by HGF antagonist and c-Met knockdown.
Potency: reported far more potent than its parent angiotensin IV in model assays.
Caveat: a key synaptogenesis paper carries a 2021 journal Notice of Concern; treat the data cautiously.
What Is Dihexa?
Dihexa is a small synthetic peptide developed at Washington State University by the Harding and Wright groups. Its full name is N-hexanoic-Tyr-Ile-(6) aminohexanoic amide, and it was engineered from angiotensin IV to survive metabolism, cross the blood-brain barrier, and remain orally active, which the native peptide cannot do.[1] It is studied as a tool for probing growth-factor-driven neuroplasticity.
How Does Dihexa Engage HGF/c-Met?
The proposed mechanism runs through hepatocyte growth factor (HGF) and its receptor c-Met. Dihexa binds HGF with high affinity and potentiates HGF signaling, inducing c-Met phosphorylation in research models.[2] The dependence on this pathway is supported by loss-of-function tests: an HGF antagonist and short-hairpin RNA knockdown of c-Met both blocked Dihexa's effects, and an HGF antagonist blocked the procognitive action of orally delivered Dihexa.[2]
Does Dihexa Drive Synaptogenesis?
In hippocampal research models, Dihexa and its parent compound induced dendritic spine formation (spinogenesis) and synaptogenesis comparable to HGF itself.[2] Because new, stable synapses are a structural basis of learning and memory, this readout is why Dihexa is studied as a probe of how a single growth-factor pathway can reshape connectivity.
How Potent Is Dihexa vs Angiotensin IV?
Dihexa was designed to be far more potent and stable than angiotensin IV, and in model assays it is reported to act at very low concentrations, which is the basis of the "most potent" language often attached to it.[1] Potency in a dish is not the same as a proven effect in an organism, so these numbers describe experimental activity, not human outcomes.
What Are the Caveats in the Evidence?
This is the part a serious reference should not skip. The central synaptogenesis study carries a 2021 Notice of Concern from the journal editors regarding possible image issues; it has not been formally retracted, but the flag means its figures should be read with caution.[2] Add to that the general limits of the field: most Dihexa data is preclinical, there are no large independent human trials, and much of the supporting work comes from a small number of groups. For research, Dihexa is an interesting HGF/c-Met tool with a genuinely open evidence question.
| Property | Detail |
|---|---|
| Class | Metabolically stabilized angiotensin IV analog |
| Structure | N-hexanoic-Tyr-Ile-(6) aminohexanoic amide |
| Target | HGF / c-Met system |
| Reported effect | c-Met phosphorylation; hippocampal spinogenesis and synaptogenesis |
| Controls | Blocked by HGF antagonist and c-Met knockdown |
| Evidence caveat | Key paper has a 2021 Notice of Concern; preclinical only |
How is research-grade Dihexa characterized?
Dihexa's modified structure makes identity confirmation important. Research-grade Dihexa is typically verified by reversed-phase HPLC for purity and mass spectrometry for identity, handled cold, and supplied for laboratory use only. At PrymaLab, research peptides are characterized with HPLC/MS verification and independent third-party testing. No specific lot data are asserted in this general reference.
Frequently Asked Questions
What is Dihexa?
A metabolically stabilized angiotensin IV analog (N-hexanoic-Tyr-Ile-(6) aminohexanoic amide) studied as an HGF/c-Met potentiator; orally active and blood-brain-barrier permeable.
How does Dihexa work?
It binds HGF and potentiates c-Met signaling, inducing c-Met phosphorylation and hippocampal spinogenesis/synaptogenesis in models; effects are blocked by HGF antagonists and c-Met knockdown.
Is the Dihexa research reliable?
The mechanism has strong loss-of-function support, but a central study carries a 2021 journal Notice of Concern and the field is preclinical with limited independent replication. Read it cautiously.
Is Dihexa approved for human use?
No. Dihexa is a research-use-only compound with no approved therapeutic use, studied only in cell and animal models.
References
- McCoy AT, Benoist CC, Wright JW, et al. Evaluation of metabolically stabilized angiotensin IV analogs as procognitive/antidementia agents. J Pharmacol Exp Ther. 2013;344(1):141–154.
- Benoist CC, Kawas LH, Zhu M, et al. The procognitive and synaptogenic effects of angiotensin IV-derived peptides are dependent on activation of the HGF/c-Met system. J Pharmacol Exp Ther. 2014;351(2):390–402. Reference
Final disclaimer: This article is an educational research reference. Dihexa is sold and studied for laboratory research use only and is not approved by any regulatory authority for human or veterinary use. Statements have not been evaluated by the FDA. Nothing here should be interpreted as medical advice.
Mechanistic descriptions are observations from cell and animal models that may not generalize, and some cited data carries a journal Notice of Concern. Always verify the legal status of any research compound in your jurisdiction before purchase or use.
