Fig. 5From: Recent advances on the molecular mechanisms of exercise-induced improvements of cognitive dysfunctionExercise improves cognitive function through the gut-brain axis. In the context of disrupted intestinal barrier, LPS and amyloid proteins may enter the brain. LPS activates aberrant polarization of astrocytes via TRL4/MyD88/lkB/NF-kB and produces large amounts of pro-inflammatory factors. This is immediately followed by microglia-mediated neuroinflammation and degeneration of motor neurons, ultimately leading to cognitive dysfunction. Exercise improves the integrity of the intestinal epithelium and increases the levels of tight junction proteins, such as ZO-1, Occludin, and Claudin. A stronger intestinal barrier reduces the entry of LPS and amyloid into the brain, and attenuates the above reactions within the brainBack to article page