Physical exercise prevents amyloid β1-40-induced disturbances in NLRP3 inflammasome pathway in the hippocampus of mice

Amyloid beta (A beta), one of the main hallmarks of Alzheimer's Disease (AD), may stimulate pattern recognition receptors (PRR) such as the NLRP3 inflammasome, inducing a pro-inflammatory state in the brain that contributes to disease development. Physical exercise can have multiple beneficial effects on brain function, including anti-inflammatory and neuroprotective roles. The objective of this study was to investigate the prophylactic effect of moderate treadmill exercise for 4 weeks on inflammatory events related to NLRP3 signaling in the hippocampus of mice after intracerebroventricular A beta(1-40) administration. Our results show that A beta(1-40) administration (400 pmol/mouse, i.c.v.) significantly increased the immunocontent Iba-1 (a microglial reactivity marker), NLRP3, TXNIP, and caspase-1 in the hippocampus of mice. However, physical exercise prevented the hippocampal increase in Iba-1, TXNIP, and activation of the NLRP3 inflammasome pathway caused by A beta(1-40). Moreover, physical exercise per se reduced the TXNIP and caspase-1 immunocontent in the hippocampus. No alterations were observed on the immunocontent of GFAP, ASC, and IL-1 beta in the hippocampus after A beta(1-40) and/or physical exercise. These results reinforce the role of NLRP3 inflammasome pathway in AD and point to physical exercise as a possible non-pharmacological strategy to prevent inflammatory events triggered by A beta(1-40) in mice.

Automated summary

The study demonstrates that A beta(1-40) may induce activation of the NLRP3 inflammasome pathway in the hippocampus of mice, but physical exercise can prevent this increase and reduce the inflammatory response caused by A beta(1-40).