GPNMB protein levels increase in astrocytes and microglia in the SN of CBE‐treated Thy1‐α‐syn mice [31] and in astrocytes in the striatum of 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP)‐treated mice [76], suggesting that it may be involved in inflammatory pathways in PD. Here, GPNMB is linked to Parkinson disease.