NFE2L2 and Parkinson disease: Our IHC data revealed distinct neuronal nuclear p-NRF2 (S40) enrichment in PD brains compared with control brains, both in SN and periaqueductal grey (PAG) regions (Compare Fig. 1A, B, Controls and 1C, D, PD; also see Fig. 1E, F and Additional file 1: Fig. S1A, B).