Effects Of Treadmill Exercise On DCX And A Beta1-42 In AD Mice

Abstract

PURPOSE: To investigate the effects of different load exercise on the hippocampal neurogenesis markers DCX and Aβ1-42 in adult AD mice. METHODS: The 3-month-old APP/PS1 dual-transgenic AD mice were randomly divided into four groups: Control group(ADC), Low-load exercise group(ADL), Medium-load exercise group(ADM) and High-load exercise group(ADH), Wild-type control group(WTC) was also be set, 6 mice in each group. ADC and WTC group mice were fed naturally for 5 months. Intervention with different loads of aerobic exercise for every exercise group. Low load running speed was 12 m/min, medium load running speed was 15 m/min, and high load running speed was 18m/min. 5d/w for 30 min/d for 5 months. Then, the Morris Water Maze (MWM) test was performed to estimate mice’ learning and memory abilities, the immunofluorescence technique was used to determine the expression levels of DCX and Aβ1-42 in the hippocampus. RESULTS: (1)In the process of navigation training, all mice’ escape latencies gradually shortened. On the second day, the average escape latency of the ADC group was significantly higher than that of the WTC group (p<0.05). Compared with the ADC group and the ADL group, the mice in the ADM group were significantly reduced from the third day, and the mice in the ADH group were significantly reduced from the fourth day (p<0.05). In the MWM navigation experiment, for the time of through the area of the original platform, ADC group was significantly reduced than WTC group (p<0.01), ADM group and ADH group was significantly higher than ADC group and ADL group (p<0.01,p<0.05). (2) Compared with WTC group, the expression of DCX in ADC group was lower but Aβ1-42 was higher(P<0.05). Compared with ADC group, the expression of DCX in every exercise group was higher but Aβ1-42 was lower(P<0.05, P<0.01). Compared with ADL group, the expression of DCX in ADM group was higher but Aβ1-42 was lower(P<0.05). CONCLUSIONS: Medium and high load exercise can significantly improve the spatial learning and memory ability of AD mice. Exercise, especially medium load exercise, can enhance the expression of DCX in AD mice and reduce the expression of Aβ1-42 in hippocampal.