PSEN1 and Alzheimer disease: A study using functional astrocytes derived from induced pluripotent stem cells (iPSCs) from patients with Alzheimer’s disease (AD) and the PSEN1 ΔE9 mutation, a condition linked to an increase in the accumulation of Aβ amyloid, showed a higher basal OCR compared with isogenic control cells, as well as increased reactive oxygen species and reduced lactate production [33].