GAPDH and Alzheimer disease: Intriguingly, when we measured aPKC expression/activity in different ages of 3xTg-AD and Non-Tg hippocampal extractions, it revealed that relative expression of total aPKC and an active form of aPKC, p-aPKC (T410/403), relative to GAPDH (as a loading control) was significantly reduced in 9-month-old 3xTg-AD hippocampi, but not 2-months-old 3xTg-AD samples (Figure 1A, C, * P < 0.05).