تأثیر 4 هفته پیش آماده سازی ورزشی بر سطح آمیلوئیدبتای محلول و اختلال حافظه در رتهای مبتلا به بیماری آلزایمر القاء شده با تزریق Aβ1-42

Background: Alzheimer's disease (AD) is the most common form of dementia and amyloid peptides playing a central role in its pathogenesis. Recently, regular exercise has been considered as one of the most important non-pharmacological mechanisms to contrast with AD. Therefore, the aim of the present study was to investigate the effect of 4 weeks of exercise preconditioning on the level of soluble amyloid and memory impairment in rats with AD induced by A&beta;1-42 injection. Methods: Eighty four male rats with mean&plusmn;SD weight of 195&plusmn;20 g were randomly divided into two groups of aerobic training or resting for 4 weeks. Then, each group was subdivided into 3 subgroups of AD, sham and non-injected. Forty eight hours after the last training session, injection of A&beta;1-42 or DMSO into the hippocampus was performed. Seven days after surgery, rats of each groups were either sacrificed (7 rats) or subjected to behavioral testing (7 rats), randomly. Following the collection of blood samples in the victim's rats, the hippocampal tissue was extracted and the levels of A&beta;1-42 in plasma and hippocampus, as well as the plasma level of the soluble Low-Density Lipoprotein Receptor-Related Protein-1 (sLRP-1) evaluated. Results: The results showed that in the exercise + AD group, hippocampal level of A&beta;1-42 were lower, and plasma level of A&beta;1-42 were higher than the AD group (p<0.001). Plasma sLRP-1 level in the exercise + AD group was also greater than the AD group (p<0.001). Moreover, spatial learning and memory were significantly better in the exercise + AD than AD group (p<0.01). Conclusion: It seems that 4 weeks of exercise preconditioning could reduce the loss of spatial learning and memory through increasing soluble amyloid beta clearance from the brain. &nbsp;