HMOX1 and Parkinson disease: The expression of Nrf2 transcription factors decreases with age in brain tissue, probably due to a decrease in the expression of Nrf2 target genes and an increase in NF-κB target genes, such as NQO1, γ-glutamylcysteine synthetase (γ-GCS), HO-1, intercellular adhesion molecule 1 (ICAM-1) and IL-6 (Silva-Palacios et al., 2018), which exacerbates the manifestations of PD.