MAPT and Alzheimer disease: Although in vitro studies are valuable to assessing the impact of Zn on tau and Aβ, changes in the levels of one metal can affect the levels of others in vivo (Maret and Sandstead, 2006; Nations et al., 2008) The use of animal models allows for more translational findings and the ability to see the impact that Zn has in conjunction with AD pathology.