A study of cells from 84 cadaver brains suggests that Alzheimer’s has two distinct phases, and that one type of neuron is especially vulnerable. “There’s an early phase where there’s a very slow increase in the amount of pathology,” says Ed Lein , a senior investigator at the Allen Institute for Brain Science in Seattle, “then a more exponential phase where suddenly things get really bad.” The study also found evidence that a small subset of neurons known as somatostatin inhibitory neurons begin to die off during the early phase of Alzheimer’s, Lein and a team of nearly 100 other scientists report in the journal Nature Neuroscience .
“That was quite a surprise,” Lein says, because these neurons have received relatively little attention from Alzheimer’s researchers. The findings suggest that Alzheimer’s treatments are most likely to help early in the disease, and that one strategy might be to protect vulnerable inhibitory neurons. The results also show how scientists’ understanding of Alzheimer’s is being changed by new tools and techniques that can reveal detailed information about millions of individual brain cells.
“They’ve produced a picture of what’s going on that no one could have anticipated just a few years ago,” says Dr. Richard Hodes , who directs the National Institute on Aging, which played a key role in funding the research. Tracking brain cell changes The study looked at more than 3.
4 million cells from the brains of people who.