HMOX1 and Cognitive impairment: The scavenging of reactive oxygen species (O2− and H2O2) by the nuclear factor erythroid 2-related factor 2 and heme oxygenase-1 (NRF2/HO-1) signaling pathway was the primary method to achieve the goal of anti-oxidation, and a promising factor for improving the cognitive impairment seen in AD [40].