United States: In a recent study analyzing brain cells from 84 cadaver samples, researchers discovered that Alzheimer’s mainly follows two distinct phases, with certain neurons particularly vulnerable in the early phase.
Further Details
Ed Lein, a senior investigator at the Allen Institute for Brain Science, explains, “There’s an early phase where there’s a very slow increase in the amount of pathology,” as reported by NPR News.
This phase is followed by “a more exponential phase where suddenly things get really bad,” Lein added.
In this early phase, a unique subset of neurons, known as somatostatin inhibitory neurons, begins to deteriorate. This was reported by Lein and his team of approximately 100 scientists.
According to Lein, “That was quite a surprise” as these neurons have received comparatively less focus in Alzheimer’s research until now.
What Do These Findings Suggest?
The research also suggests that Alzheimer’s treatments could be more beneficial if administered early on to protect these vulnerable inhibitory neurons.
The study highlights how innovative tools and methodologies are enabling scientists to gain new insights into Alzheimer’s, providing detailed data on the millions of brain cells affected.
Dr. Richard Hodes, director of the National Institute on Aging, which helped fund the research, stated, “They’ve produced a picture of what’s going on that no one could have anticipated just a few years ago,” according to NPR News.
How Are Brain Changes Tracked?
The team examined data from over 3.4 million cells from individuals aged 65 and older, with samples ranging from healthy brains to various Alzheimer’s stages.
The researchers focused on the middle temporal gyrus, a region involved in language, memory, and vision, to establish a timeline of how Alzheimer’s alters the brain.
As Lein described, “We measure all the genes in each individual cell,” allowing researchers to identify specific cells and observe disease-induced changes.
“We were looking for vulnerable cell populations, for instance, certain types of neurons that might be lost early in the disease,” Lein added.
“But it turns out that the first cells lost are actually some of the inhibitory neurons,” he concluded.