NFE2L2 and Parkinson disease: PCs can act on cellular mechanisms that cause DN degeneration through the modulation of gene expression and the activation of antioxidant enzymes regulated by the nuclear factor erythroid 2-related factor 2 (NrF2) pathway, thus suggesting great neuroprotective potential for PD (Magalingam et al., 2015; Hussain et al., 2018; Kujawska and Jodynis-Liebert, 2018).