PSEN1 and Alzheimer disease: After 6 h, Rg3 (50 μM) has been found to reduce Aβ levels in cultured primary neurons and in the brains of mice models of Alzheimer’s disease by decreasing the association of presenilin-1 (PS1) with lipid rafts and inhibiting Υ-secretase activity (Kang et al., 2013).