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Led by Todd Cohen, PhD, assistant professor of neurology, UNC scientists used human cell cultures to show how amyloid beta can trigger a dramatic inflammatory response in immune cells and how that interaction damages neurons. Then they showed how that kind of neuron damage leads to the formation of bead-like structures filled with abnormal tau protein . Similar bead-like structures are known to form in the brain cells of people with Alzheimer's disease. The UNC researchers also identified two proteins -- MMP-9 and HDAC6 -- that help promote this harmful, amyloid-to-inflammation-to-tau cascade. These proteins and others associated with them could become drug targets to treat or prevent Alzheimer's. "It's exciting that we were able to observe tau -- the major Alzheimer's protein -- inside these beaded structures," said Cohen, who is also a member of the UNC Neuroscience Center. "We think that preventing these structures from forming would leave people...

"In humans, navigation is much more cumbersome to research than learning or memory," says Thomas Wolbers, a neuroscientist specializing in aging and cognition at the German Center for Neurodegenerative Diseases . "But it has such a dramatic impact on everyday life, and the key structures of the 'navigational network' in the brain are very sensitive to both ordinary healthy aging and pathological factors." Currently, Alzheimer's disease is diagnosed based on an individual's medical history, genetic risk factors, and performance on tests that measure memory, language, and reasoning impairments. Wolbers and his colleagues from the United States and the United Kingdom suggest that navigational impairments are among the earliest signs of the Alzheimer's progression. Healthy older individuals, for instance, strongly prefer to map objects and landmarks relative to their body position (an egocentric strategy) rather than in relation to external obje...