DKK1 and Alzheimer disease: Furthermore, persistent activation of Wnt signaling, via Wnt ligands or by inhibiting negative regulators [e.g., DKK-1, GSK-3β, and soluble Frizzled related protein (sFRP)], is indeed able to overcome the toxic effects induced by Aβ and ameliorate cognitive performance in AD [2, 21, 25, 61, 76, 78–84].