Researchers at the University of California - Irvine, say that stress hormones can rapidly accelerate the formation of the brain lesions that cause Alzheimer's disease. Based on these findings, the researchers suggest that managing stress and reducing certain medications used by the elderly could significantly slow down the progression of the disease.
Reported in the Journal of Neuroscience, the researchers said the study findings will have profound implications for how to treat the elderly who suffer from Alzheimer's disease. "It is remarkable that these stress hormones can have such a significant effect in such a short period of time," researcher Frank 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."
The study was conducted with genetically modified mice, which were injected with dexamethasone, a chemical similar to the body's own stress hormones. After only one week, the levels of the Alzheimer's protein beta-amyloid increased by 60 percent. These levels of beta-amyloid are compararable to what is seen in the brains of untreated eight- to nine-month-old mice, demonstrating the profound consequence of glucocorticoid exposure.
Even more noteworthy were the effects of the dexamethasone when given to 13-month-old mice that already had some plaque in the brain. In these cases, the hormone significantly worsened the existing plaque lesions in the brain and led to increased accumulation of another tell-tale Alzheimer's protein.
Stress management was now emerging as an important factor in treating Alzheimer's disease, according to co-researcher Kim Green, who said that medications routinely given to the elderly may need to be re-examined. "Some medications prescribed for the elderly for various conditions contain glucocorticoids. These drugs may be leading to accelerated cognitive decline in patients in the early stages of Alzheimer's," explained Green.
Source: University of California - Irvine