On the other hand, enhancement of intracellular copper levels through addition of dietary copper in APP/PS1 transgenic AD mice (Crouch et al., 2009) and APP23 transgenic mice (Bayer et al., 2003) with parenchymal plaques but no neuronal loss (Elder et al., 2010; Sasaguri et al., 2017), causes a reduction in AD pathology. Here, APP is linked to Alzheimer disease.