Iron is known to play a significant role in the neurotoxicity associated with AD and PD, as evidenced by the presence of 5′-untranslated region (5′-UTR) IRE sequences in the transcripts of the APP and α-synuclein (α-syn), the activity of APP as a neuronal iron export ferroxidase, and the ability of iron to increase the neurotoxicity of Aβ [24]. Here, APP is linked to Parkinson disease.