The findings suggest that managing stress and reducing certain medications prescribed for the elderly could slow down the progression of this devastating disease.
In a study with genetically modified mice, Frank LaFerla, professor of neurobiology and behavior, and a team of UCI researchers found that when young animals were injected for just seven days with dexamethasone, a glucocorticoid similar to the body’s stress hormones, the levels of the protein beta-amyloid in the brain increased by 60%.
When beta-amyloid production increases and these protein fragments aggregate, they form plaques, one of the two hallmark brain lesions of Alzheimer’s disease.
The scientists also found that the levels of another protein, tau, also increased. Tau accumulation eventually leads to the formation of tangles, the other signature lesion of Alzheimer’s. The findings appear in this week’s issue of the Journal of Neuroscience.
“It is remarkable that these stress hormones can have such a significant effect in such a short period of time,” LaFerla said. “Although we have known for some time that higher levels of stress hormones are seen in individuals in the early stages of Alzheimer’s, this is the first time we have seen how these hormones play such a direct role in exacerbating the underlying pathology of the disease.”