MT-3 plays an important role in brain zinc and copper homeostasis, which is expressed mainly in the brain, where it is particularly abundant in zinc-enriched neurons (ZEN), astrocytes, cerebellar cortex, and the early degenerated hippocampus in AD [85, 86]; In contrast, brain MT-1 and MT-2 are mainly expressed in glia cells and mainly in the astrocytes [85]. This evidence concerns the gene MT3 and Alzheimer disease.