CTSD and Parkinson disease: et Vant., has been suggested to be neuroprotective in PD.322 In the postmortem striatum of sporadic PD patients, the level of microglial Nramp1 was found to be significantly increased, accompanied by iron deposition and α-synuclein aggregation.323 Under conditions of iron overload, functional Nramp1 is involved in the degradation of α-synuclein aggregates with lysosomal cathepsin D in microglia.323