HSPA5 and Alzheimer disease: The integration of the ER stress response in CR pups relative to AD pups was indicated by a significant increase in the ratio of XBP1s/XBP1u gene expression (Fig. 4F) as well as the protein expression of p-IRE1α (Fig. 4G), p-eIF2α (Fig. 4H), and CHOP (Fig. 4I), but not GRP78, an endogenous chaperone protein that inhibits hepatic lipogenesis (Fig. 4J).