Alzheimer's Linked to Breakdown in Brain's Cleaning Process

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Researchers continue to piece together what causes Alzheimer’s. Right now, we know that poor sleep is linked to the disease, but as to whether it’s a cause or a side effect has yet to be determined. Researchers understand that as we age, the chances of getting the disease rise. Once people reach age 65, their risk doubles every five years. This increased risk has to do with our brain’s ability to clear out the gunk, if you will.

Researchers from the Washington University School of Medicine in St. Louis have found that as we age, a change takes place centering onamyloid beta 42, a chemical that’s responsible for plaque buildup in the brain, which leads to the development of Alzheimer’s. However, there’s a disposal process in place that helps to clear out all this gunk before it has a chance to clump together and create amyloid plaques.

The paper, which was published in the Annals of Neurology, details how the researchers analyzed the amount of amyloid beta 42 in “112 participants and compared to the ages of participants and the amount of amyloid deposition.”

Senior author of the study, Randall J. Bateman, reported their results to Medical Xpress:

“We found that people in their 30s typically take about four hours to clear half the amyloid beta 42 from the brain. In this new study, we show that at over 80 years old, it takes more than 10 hours.”

There’s a slower turnover rate of amyloid beta, which means one or several of the disposal processes may be malfunctioning. Scientists believe that there are four ways the brain uses to channel the excess amyloid beta: by moving it across the blood-brain barrier, having other proteins absorb it, creating plaques, or directing it into the spine.

Bateman said:

“Through additional studies like this, we’re hoping to identify which of the first three channels for amyloid beta disposal are slowing down as the brain ages. That may help us in our efforts to develop new treatments.”