Intracellular and extracellular microtubule associated protein tau as a therapeutic target in Alzheimer disease and other tauopathies.

Introduction: Microtubule associated protein tau, a protein mainly expressed in neurons, plays an important role in several diseases related to dementia, named tauopathies. Alzheimer disease is the most relevant tauopathy. The role of tau protein in dementia is now a topic under discussion, and is the focus of this review.