HMOX1 and Parkinson disease: Moreover, heme Oxygenase-1 (HSP32) has been described as being induced and playing a role in the degradation of heme into ferrous iron in the neurons and astrocytes of the hippocampus and cortex in AD patients as well as in the astrocytes of the striatum nuclei of PD patients, possibly leading to iron toxicity through the induction of oxidative stress via the Fenton reaction [181,182,183,184].