BDNF and Alzheimer disease: Estradiol promotes BDNF signaling induction (10), acts as an antioxidant and promotes cell survival (9, 11), protects against stroke damage (72, 73), prevents insulin resistance (11), and prevents protein aggregation of AD hallmarks Aβ (71) and phosphorylated tau (pTau) tangles (69, 74), effectively protecting neurons from energy loss and excitotoxicity.