A good night’s sleep is essential for keeping the brain healthy, yet sleep problems are one of the earliest signs of Alzheimer’s disease.
Now researchers believe they have discovered why. Instead of blaming the disease’s famous amyloid plaques alone, they found that the brain’s own defense system may be accidentally causing the problem. The research was published in Alzheimer’s & Dementia.
Alzheimer’s disease affects millions of people worldwide. It slowly destroys memory and thinking abilities, but changes inside the brain begin many years before symptoms appear.
Poor sleep is often one of the first warning signs, making it an important target for researchers.
The brain contains immune cells called microglia. Their normal job is to protect the brain by removing waste, fighting infection, and cleaning up damaged tissue. When amyloid plaques appear, however, these cells become highly active and release inflammatory signals.
Scientists at the University of Kentucky wondered whether this immune reaction, rather than the plaques themselves, was preventing healthy sleep. They tested the idea using mice genetically programmed to develop Alzheimer’s-like brain changes. Brain wave recordings allowed them to monitor sleep with great precision.
The researchers found that the biggest sleep disruption happened soon after plaques first appeared. Surprisingly, adding many more plaques later did not make sleep much worse. This finding suggested that the immune response triggered early in the disease may be more important than the total amount of plaque.
Next, the team temporarily removed most of the microglia using an existing research drug. Almost immediately, the Alzheimer’s mice slept for more than two additional hours each day. Importantly, the plaques did not disappear, showing that restoring sleep did not require removing the protein deposits.
The extra sleep mainly occurred during deep restorative sleep, the stage when the brain strengthens memories and clears away waste products. Scientists believe this cleaning process helps maintain healthy brain function. Losing it may contribute to faster progression of Alzheimer’s disease.
The study also identified changes in electrical brain activity that could one day become a simple way to detect Alzheimer’s disease. The researchers believe portable EEG devices might eventually help doctors monitor patients at home and identify brain changes before serious memory loss develops.
The team is now searching for safer ways to calm overactive microglia instead of removing them completely. Existing medicines already used for other diseases could potentially be adapted if future studies confirm they reduce harmful brain inflammation.
Study analysis: This is an exciting and potentially important discovery because it challenges one of the traditional explanations for sleep loss in Alzheimer’s disease. However, it remains early-stage research performed in animals, so it does not prove the same treatment will work in people.
If future clinical studies support these findings, targeting brain inflammation may become an entirely new approach for improving sleep and quality of life in Alzheimer’s patients.
If you care about Alzheimer’s disease, please read studies that bad lifestyle habits can cause Alzheimer’s disease, and strawberries can be good defence against Alzheimer’s.
For more health information, please see recent studies that oral cannabis extract may help reduce Alzheimer’s symptoms, and Vitamin E may help prevent Parkinson’s disease.
Source: University of Kentucky.
