اثر تمرين استقامتي قبل از القاي آلزايمر بر يادگيري، حافظه و تغييرات گاما سكرتاز هيپوكمپ در رت هاي نر نژاد ويستار

The Effect of Endurance Training Before Induction of Alzheimers on Learning Memory and the Changes in Hippocampal Gamma-secretasein Male Wistar Rats

اﯾﻦ ﭘﮋوﻫﺶ ﺑﺎ ﻫﺪف ﺑﺮرﺳﯽ اﺛﺮ ﺗﻤﺮﯾﻦ اﺳﺘﻘﺎﻣﺘﯽ ﻗﺒﻞ اﻟﻘﺎي آﻟﺰاﯾﻤﺮ ﺑﺮ ﯾﺎدﮔﯿﺮي، ﺣﺎﻓﻈﻪ و ﺗﻐﯿﯿﺮات ﮔﺎﻣﺎﺳﮑﺮﺗﺎز ﻫﯿﭙﻮﮐﻤﭗ ﻣﻮ ﻫﺎي ﻧﺮ ﻧﮋاد وﯾﺴﺘﺎر اﻧﺠﺎم ﺷﺪ. 32 ﺳﺮ رت ﻧﺮ ﺑﺎﻟﻎ 8 ﻫﻔﺘﻪاي ﺑﺎ ﻣﯿﺎﻧﮕﯿﻦ وزﻧﯽ 17 ± 250 ﮔﺮم، ﻗﺒﻞ از اﻟﻘﺎي آﻟﺰاﯾﻤﺮ ﺑﻪ ﺻﻮرت ﺗﺼﺎدﻓﯽ ﺑﻪ دو ﮔﺮوه اﺳﺘﺮاﺣﺖ )16 ﺳﺮ( و ﺗﻤﺮﯾﻦ )16 ﺳﺮ( ﺗﻘﺴﯿﻢ ﺷﺪﻧﺪ. ﭘﺲ از 4 ﻫﻔﺘﻪ )ﻫﻔﺘﻪ اول و دوم ﺑﺎ ﺳﺮﻋﺖ 10 ﻣﺘﺮ ﺑﺮ دﻗﯿﻘﻪ در دو ﻧﻮﺑﺖ 15 دﻗﯿﻘﻪ اي، ﻫﻔﺘﻪ ﺳﻮم ﺑﺎ ﺳﺮﻋﺖ 15 ﻣﺘﺮ ﺑﺮ دﻗﯿﻘﻪ در ﺳﻪ ﻧﻮﺑﺖ 15 دﻗﯿﻘﻪ اي و در ﻫﻔﺘﻪ ﭼﻬﺎرم ﺑﺎ ﺳﺮﻋﺖ 15 ﻣﺘﺮ ﺑﺮ دﻗﯿﻘﻪ در ﭼﻬﺎر ﻧﻮﺑﺖ 15 دﻗﯿﻘﻪ اي ﺑﺎ وﻗﻔﻪ 5 دﻗﯿﻘﻪ اي(، ﻫﺮ ﮔﺮوه ﺑﻪ دو زﯾﺮﮔﺮوه: 1- ﺗﺰرﯾﻖ آﻣﯿﻠﻮﺋﯿﺪﺑﺘﺎ و 2- ﺑﺪون ﺗﺰرﯾﻖ ﺗﻘﺴﯿﻢ ﺷﺪﻧﺪ... ﻫﻤﭽﻨﯿﻦ، ﮔﺎﻣﺎ ﺳﮑﺮﺗﺎز در ﮔﺮوه ﺗﻤﺮﯾﻦ ﻧﺴﺒﺖ ﺑﻪ ﮔﺮوه اﺳﺘﺮاﺣﺖ در ﻣﺮﺣﻠﻪ ﺑﻌﺪ از اﻟﻘﺎي آﻟﺰاﯾﻤﺮﮐﺎﻫﺶ ﻣﻌﻨﺎداري را ﻧﺸﺎن داد )0/001= p(. ﺗﻤﺮﯾﻦ ﻫﻮازي ﻗﺒﻞ از اﻟﻘﺎي آﻟﺰاﯾﻤﺮ ﻣﻨﺠﺮ ﺑﻪ ﮐﺎﻫﺶ ﮔﺎﻣﺎ ﺳﮑﺮﺗﺎز و اﻓﺰاﯾﺶ ﯾﺎدﮔﯿﺮي و ﺣﺎﻓﻈﻪ و از اﯾﻦ ﻃﺮﯾﻖ اﻣﮑﺎن دارد ﺑﻪ ﺷﮑﻞﭘﺬﯾﺮي ﻫﯿﭙﻮﮐﺎﻣﭙﯽ ﮐﻤﮏ و ﻓﻮاﯾـﺪ ﺷـﻨﺎﺧﺘﯽ و ﻋﻤﻠﮑﺮدي در ﭘﯽ داﺷﺘﻪ ﺑﺎﺷﺪ.

This study aimed to investigate the effect of endurance training before induction of Alzheimers on learning, Memory and changes in the hippocampal gamma-secretase in male Wistar rats. For this purpose, 32 8-week-old mature male rats with the avergae weight of 250±17g were randomly divided into two groups of rest (16) and exercise (16) beore Alzheimers induction. After 4 weeks (two 15-min intervals with the speed of 10 m/min in first and second weeks, three 15-min intervals with the speed of 15 m/min in the third week,and four 15-min intervals with the speed of 15 m/min in the fourth week, with 5-min stops), each group was divided into two subgroups: 1. Amyloid beta injection, and 2. no injection. After 72 hours, the animals were killed and their hippocampus was removed. The changes of gamma secretase were measured by Real Time PCR and the obtaiend data analyzed by one-way ANOVA. Morris learning and memory test revealed a significant difference between the time elapsed for finding the platform in different groups on the second (p = 0.001, F = 10.758), third (p ≥ 0.001, p = 0.0057) and the fourth days (p = 0.001, F = 4.846). The time elapsed for finding the platform in the rest-injection group Aβ1-42 was significantly longer than the other gorups on all days (p ≥ 0.001). The results of probe test for spatial memory showed that the time spent in the quadrant of the target circle was significantly different for different groups (p = 0.001, F = 9.25). Also, gamma secretase was significantly decreased in the exercise group compared to rest group after Alzheimers induction (p = 0.001). Aerobic exercise before Alzheimers induction leads to a decrease in gamma-secretase and increase in learning and Memory, and it may lead to hyppocampal plasticity that brings about cognitive and functional benefits.