Alzheimer’s disease

A fluroescent-tagged antibody bearing silver and gold particles reveals I and L bradykinin receptors lit in a ghostly green glow on the surfact of cultured human cellsPreliminary research suggests it may someday be possible to diagnose and forecast risk for Alzheimer’s disease using skin cells, thanks to a small protein, or peptide, that few previously associated with the disease. Researchers at Washington University School of Medicine in St. Louis have discovered that skin cells from people with inherited forms of Alzheimer’s disease respond to the peptide by triggering Alzheimer’s-like changes, but skin cells from healthy individuals do not. They say the findings need to be explored further in cases of non-inherited Alzheimer’s disease, but the results could eventually lead to a way of determining an individual’s risk of developing Alzheimer’s before clinical symptoms arise.

With the graying of America, millions of people across the nation are facing the same tough question: when do older people become unsafe drivers? In one of the first studies to track driving performance in older adults, researchers at Washington University in St. Louis found that over time, driving abilities predictably worsen in individuals with early Alzheimer’s disease and, to a lesser extent, in older adults without dementia. People with mild dementia had the fastest rate of decline, but there also were declines in nondemented study participants. The researchers also found that increased age alone appeared to be a risk factor in driving performance. Because Alzheimer’s disease is progressive and driving performance inevitably does worsen, the challenge is to figure out how to predict and evaluate dangerous declines in driving performance. The researchers suggest that testing individuals with mild dementia every six months might be a useful way to keep unsafe drivers off the roads.

Image courtesy of Cindy LustigParts of the brain involved in a “resting network” show large differences between young adults, older adults, and people with Alzheimer’s disease.Researchers tracking the ebb and flow of cognitive function in the human brain have discovered surprising differences in the ability of younger and older adults to shut down a brain network normally active during periods of passive daydreaming. The differences, which are especially pronounced in people with dementia, may provide a clear and powerful new method for diagnosing individuals in the very early stages of Alzheimer’s disease.

At the time of the first MRI scans, the turquoise color shows areas of the hippocampus in patients with mild Alzheimer’s disease that are shaped differently than in healthy older people. Two years later, even more changes have occurred, represented by the purple color.Even when people have no symptoms, their brains already may be dotted with the plaques and tangles that characterize Alzheimer’s disease. As treatments to halt the progress of Alzheimer’s disease appear on the horizon, scientists are looking for new ways to identify Alzheimer’s-associated changes in the brain before cognitive decline begins. By examining brain images, researchers, led by John G. Csernansky, M.D., the Gregory B. Couch Professor of Psychiatry, and Lei Wang, Ph.D., research associate in psychiatry, both at Washington University’s Silvio Conte Center for Neuroscience Research, found that the volume and shape of certain brain structures change in different patterns during Alzheimer’s disease than in healthy aging. They believe that someday using these imaging techniques may allow for earlier diagnosis of Alzheimer’s disease, preferably before the most devastating symptoms appear.