PSEN1 and Alzheimer disease: Microglial (Benveniste et al., 2001; von Bernhardi and Ramirez, 2001; Lopes et al., 2008) and astrocyte (Schubert et al., 2009) involvement are known to occur in the AD brain and have also been reported in the APP/PS1 mouse brain (Wegiel et al., 2001, 2003).