In the course of our lifetime, we often encounter stress in either high or low levels. Well, it now appears connected with Alzheimer’s disease. Researchers from the Max Planck Institute of Psychiatry in Munich claim that stress hormones lead to generation of abnormally phosphorylated tau protein in the brain and ultimately, memory loss. It probably promotes neuropathological changes that are also seen in Alzheimer’s disease.
In the course of the research, it was pointed out that stress, and the hormones released during stress can fasten the development of Alzheimer disease-like biochemical and behavioral pathology. For proving this assumption scientists subjected rats to stress by overcrowding, placement on a vibrating platform for an hour everyday over a period of one month. Animals then revealed alterations in tau and deficits in memories that depended on an intact hippocampus.
“Viewing stress as a trigger of Alzheimer’s disease offers exciting new research possibilities aimed at preventing and delaying this severe disease. Moreover, since vulnerability to major depression is known to be increased by stress, it will be interesting to know the role of molecules such as beta-amyloid and tau in the onset and progress of this condition,” remarked Osborne Almeida from the Max Planck Institute of Psychiatry.
The mice allegedly had elevated hyperphosphorylation of tau protein in the hippocampus and prefrontal cortex. Those with abnormally hyperphosphorylated tau probably were impaired in behavioral flexibility, a function vital for accurate functioning of the prefrontal cortex. The research concludes that stress hormones and stress may indeed cause modifications in the tau protein like those occurring in Alzheimer’s disease.
Additional investigations will be conducted to determine how applicable the results obtained in animals are to the development of non-familial forms of Alzheimer’s disease.