Researchers have for years observed that patients regularly taking ibuprofen, naproxen or other nonsteroidal anti-inflammatory drugs seem to have less risk of developing Alzheimer's disease. Some researchers hypothesize that the Alzheimer's-diseased brain is actually inflamed and that damage happens when the microglia, the brain's immune cells, become overactive and attack healthy neurons. New research, however, indicates that the opposite may be happening--that, as microglia age, they lose their ability to protect the brain.
Wolfgang J. Streit and his colleagues at the University of Florida compared autopsy tissue from two nondemented brains, one of a 38-year-old man and the other of a 68-year-old man. Many of the microglia in the older man's brain had lost their fine branches or were otherwise deformed. Streit found even more of these withered microglia in the brains of people who also had high levels of beta-amyloid protein--a hallmark of Alzheimer's. Streit hypothesizes that beta-amyloid may cause the deformities in microglia.