Dihexa in Clinical Trials: What We've Learned So Far Stem cell, Granulocyte Colony Stimulating Factor and or Dihexa to promote limb function recovery in a rat sciatic nerve damage repair model: Experimental animal studies ScienceDirect Dihexa Peptide Dallas Cognitive Enhancement & Brain Health 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 Dihexa Wikipedia