OCLN and Alzheimer disease: Our results show that serum LPS and TNF−α were significantly elevated (p < 0.01), brain LPS were significantly elevated (p < 0.01), and the abundances of blood–brain barrier proteins occludin, ZO−1, and claudin−5 were reduced (p < 0.05 or p < 0.01) in AD mice compared with wildtype mice, trends that were reversed by exercise (Figure 6A–G), which attenuated the occurrence of intestinal and cerebral leaks.