Effects of Voluntary Wheel Running Exercise on Learning and Memory Function of Young Mice and Related Mechanisms

Abstract

Objective: This study is to investigate the effects of appropriate exercise on learning and memory function of mice, and the related mechanisms involving PAI-1 and miRNA (miR)-30b. Methods: Mice were subjected to the voluntary wheel running exercise training for 8 m. Morris water maze test was performed to assess the animal learning and memory function. Quantitative real-time PCR was conducted to detect the mRNA expression levels, while Western blot analysis and ELISA were used to determine protein expression levels. Bioinformatics analysis and dual-luciferase reporter assay were used to predict and confirm the up-stream regulator of PAI-1. Results: Morris water maze test showed that, compared with the control group, the escape latency was significantly declined in the exercise group. The swimming distance was significantly declined, while the platform crossing number was significantly increased, in the exercise group. Quantitative real-time PCR and Western blot analysis showed that, compared with the control group, the mRNA and protein expression levels of PAI-1 in both the hippocampal and blood tissues were significantly declined in the exercise group. According to the bioinformatics analysis, miR-30b might be the up-stream regulator of PAI-1, which was confirmed by the dual-luciferase reporter assay. In addition, compared with the control group, the expression levels of miR-30b in both the hippocampal and blood tissue samples were significantly elevated for the exercise group. Conclusion: Appropriate amount of exercise could improve the mouse learning and memory function, which might involve the up-regulated miR-30b expression and down-regulated PAI-1 expression in the hippocampal and blood tissues.