Evaluation of high-strength exercise on Alzheimer's disease using microarray and bioinformatics tools
Evaluation of high-strength exercise on Alzheimer's disease using microarray and bioinformatics tools
negar abdolahzadeh,1samira sasan,2abolfazl hasanramezani,3Elham fereydouni,4javad amini,5,*
1. Bojnourd University of Medical Sciences, Faculty of Medicine, Novel Technologies, North Khorasan, Iran. 2. Bojnourd University of Medical Sciences, Faculty of Medicine, Novel Technologies, North Khorasan, Iran. 3. Bojnourd University of Medical Sciences, Faculty of Medicine, Novel Technologies, North Khorasan, Iran. 5. Bojnourd University of Medical Sciences, Faculty of Medicine, Novel Technologies, North Khorasan, Iran.
Introduction: Alzheimer's disease, which stands as the most commonly observed cause of dementia, manifests itself through anomalous modifications in the brain, eventually culminating in a drastic deterioration of cognitive faculties and alterations in conduct and personality. Individuals suffering from Alzheimer's disease display a plethora of semantic incapacities, alongside functional inadequacies in the respective domains, which impede the normal activation of cognitive processes. The field of cognitive neuroscience, in its quest to augment comprehension of the fundamental biological mechanisms that underlie Alzheimer's disease, endeavors to formulate and implement preventive and therapeutic interventions premised on the latest research findings.
Population aging is a global phenomenon, according to statistics, 1.5 billion elderly people are expected in 2050. On the other hand, Alzheimer's disease is known as the most common cause of neuronal degeneration in the elderly.
This disease affects many parts of the brain and causes disturbances in the patient's activities, including memory, thinking, learning speech and judgment. Studies show that the life expectancy of Alzheimer's patients after diagnosis is only nine years. While in 2016, around 47 million people around the world were struggling with dementia. As per the findings of the World Alzheimer's Disease Report 2021, it has been observed that an enormous number of human beings, exceeding 55 million in total, are currently grappling with the complex and challenging condition of cognitive impairment on a global scale. Forecasts show that this number will reach 131 million people in 2050.
One of the important parts of the brain that is damaged in Alzheimer's disease is the hippocampus. It has been found that the volume of the hippocampus in Alzheimer's patients decreases by about 3 to 5 percent every year. Decreased hippocampal volume leads to memory impairment and increased risk of dementia. Considerable scientific data has suggested that environmental variables, such as physical activity and diet, can engender improved cognitive performance. Also has been shown that physical activity can be beneficial for cognitive function in people with neurodegenerative disease, regular activity is associated with various structural changes in the nervous system, especially in the hippocampus.
Considering the positive effects of exercise on the health of the elderly, the importance of examining the effect of exercise on these patients is essential. In this study, changes in gene expression, protein network and cellular pathways under the influence of high-intensity exercise on the hippocampus were investigated and compared with Alzheimer's disease.
Methods: Hippocampal tissue microarray data (effective high-intensity exercise) in GEO database were analyzed by GEO2R online software. DiseGeNET database employed for the increased genes expressed were examined with Alzheimer's disease-related genes. Also, STRING database was used to examine protein connections, then the resulting network was analyzed with Cytoscape software. The Enrichr database was also used to examine cellular pathways.
Results: The results showed that nearly 20 percent of the increased expression genes in high-strength are associated with Alzheimer's disease. Among them, three genes ARGGAP36, PDYN and HLA-DQA1 had the highest expression and in protein network analysis, SNAP25, SYT1 and GABRG2 proteins had the highest degree. Also, with increasing sports activity, the amount of neuronal growth factors increases. On the other hand, MAPK and cAMP cell pathways are activated.
Conclusion: Increased exercise increases the expression of growth factors and genes related to calcium homeostasis in the hippocampus. But it also activates cellular pathways such as MAPK and cAMP. It seems that managing these cellular pathways can improve the beneficial effect of exercise on Alzheimer's disease.