MAPT and Alzheimer disease: Furthermore, pre-administration of DeHE via vena caudalis for one week effectively improved the Wortmannin and GF-109 203X (WT/GFX) induced spatial memory retention impairment of rats, antagonized tau hyperphosphorylation at multiple Alzheimer's disease site and arrested the overactivation of glycogen synthase kinase-3 induced by WT/GFX [63].