DKK1 and Alzheimer disease: Dkk1 is an antagonist of the Wnt/β‐catenin pathway, thus, an increased effect of Dkk1 has been proposed as one of the contributors to AD pathogenesis by promoting Aβ‐induced synaptic loss, tau hyperphosphorylation and neuroinflammation both in vitro, and ex vivo.49, 50, 51