Low-Level Chronic Stress is a Risk Factor for the Development of Alzheimer’s Disease

The development of the sporadic type of AD, which represents 95% of cases, is associated with various risk factors, both genetic and environmental. Although the principal risk factor is aging, chronic stress has also been related to the appearance of this disease. “Our study seeks to determine whether a process of low-level chronic stress, similar to the classic stress experienced in daily life, could have an influence on the appearance of this neurodegenerative disease. We used young mice with induced Alzheimer’s, but which did not yet present the characteristic features of the disease. After submitting them to a six-week-long protocol of chronic stress, we observed that these animals presented severe memory loss and a significant increase in the two principal markers of AD: the beta-amyloid peptide and the protein Tau phosphorylate, two proteins that accumulate in the brain of AD patients. Therefore, we confirmed that low-level stress, applied in a chronic manner, contributes to aggravate and accelerate the principal features of the disease in these animals, which presented a genetic predisposition to develop Alzheimer’s”, explained Dr. Mar Cuadrado, a researcher in the area of Neurosciences of the CIMA and principle author of the article.

There are many studies that testify to the phenomenon whereby stress produces cognitive deterioration. In addition, patients with depression have episodes of memory loss and stress is one of the factors that are associated with depression. “In our article, we have confirmed that stress could directly affect the markers proper to Alzheimer’s disease”, commented Dr. Cuadrado.

Currently, the researchers of the CIMA seek to utilize these results in order to obtain animal models which develop all of the characteristics of Alzheimer’s patients. “In this way, we can more reliably test new molecules designed for the treatment of AD”, she indicated.