HMOX1 and neurodegenerative disease: Upregulated Nrf2 activates other endogenous redox-regulated enzymes, such as heme oxygenase-1 (HO-1) and glutathione cysteine ligase modulatory subunit (GCLM), consequently counteracting the ROS-induced oxidative stress and providing beneficial effects in various diseases, particularly neurodegenerative diseases [7–9].