Surprise: HDAC Goes Down, Not Up, in Alzheimer's Disease ALZFORUM The history of Alzheimers Disease Dihexa (also known as PNB 0408) is an experimental small molecule derived from angiotensin IV. It was engineered to cross the bloodbrain barrier and has shown synaptogenic effects in preclinical models. The often quoted How does Dihexa Powder work in the brain? Salispharm Dihexa MedChem Express Dihexa Research Grade Neurotrophic Molecule 20 mg PRG