NFE2L2 and Parkinson disease: Although association studies between NRF2 and UCHL-1 in PD have not yet been carried out, UCHL-1 is co-regulated with NRF2 in hyperglycaemia models [115], and NRF2 pathway has been proposed as a possible therapeutic approach for traumatic brain injury, where UCHL-1 is also upregulated [116]; however, a direct link between these two remains to be established.