PROS1 and Alzheimer disease: Characterization of NCAM and PSA-NCAM expression in AD and WT mice with aging through immunoblotting revealed a significant reduction in PSA-NCAM expression in old AD mice when compared to age-matched WT mice, across all regions (hippo, ANOVA, p < 0.001, F (1, 12) = 36.82; pfc, ANOVA, p < 0.001, F (1, 12) = 41.5; ctx, ANOVA, p < 0.001, F (1, 12) = 72.4; mb, ANOVA, p < 0.001, F (1, 12) = 21.4, n ≥ 4; Figures 5A,C).