Human aging results in physiological brain calcification (Yamada et al., 2013) and a precipitous decline in the adult neural stem or progenitor cells with concomitant cognitive impairment (van Praag et al., 2005; Villeda et al., 2011), similar to the phenotypes of Slc20a2-HO mice (Ren et al., 2021). Here, HMOX1 is linked to Cognitive impairment.