Scientists find the key driver of Alzheimer’s disease development

Credit: Unsplash+

In a study from the University of Pittsburgh and elsewhere, scientists found neuroinflammation is the key driver of the spread of pathologically misfolded proteins in the brain and causes cognitive impairment in patients with Alzheimer’s disease.

They showed in living patients that neuroinflammation—or activation of the brain’s resident immune cells, called microglial cells—is not merely a consequence of disease progression.

Rather, it is a key upstream mechanism that is indispensable for disease development.

The research suggests that combination therapy aimed to reduce amyloid plaque formation and limit neuroinflammation might be more effective than addressing each pathology individually.

Alzheimer’s disease is characterized by the accumulation of amyloid plaques—protein aggregates lodged between nerve cells of the brain—and clumps of disordered protein fibers, called tau tangles, forming inside the nerve cells.

Although studies in cultured cells and lab animals amassed ample evidence that microglial activation drives the spread of tau fibers in Alzheimer’s disease, this process has never been proven in humans.

The study findings suggest that targeting neuroinflammation might be beneficial for people with early-stage Alzheimer’s disease and that it might help reverse or at least slow down the accumulation of pathologic tau protein in the brain and stave off dementia.

To determine the mechanism by which disordered tangles of tau protein fibers and amyloid plaques spread across the brain and lead to dementia, the researchers used live imaging to look deep into the brains of people with various stages of Alzheimer’s disease and healthy aging individuals.

They found that neuroinflammation was more prevalent in older people and that it was even more pronounced in patients with mild cognitive impairments and those with Alzheimer’s disease-associated dementia.

Bioinformatics analysis confirmed that tau propagation depended on microglial activation—it is a key element that links the effects of amyloid plaque aggregation to tau spread and, ultimately, cognitive impairment and dementia.

The team says the results suggest that it is the interaction between neuroinflammation and amyloid pathology that unleashes tau propagation and eventually leads to wide-spread brain damage and cognitive impairment.

If you care about Alzheimer’s disease, please read studies about possible way to delay or reverse Alzheimer’s disease, and how to treat mild to moderate Alzheimer’s disease.

For more information about brain health, please see recent studies about alternative drug strategy against Alzheimer’s disease, and strawberries could help prevent Alzheimer’s disease.

The study was conducted by Tharick Pascoal et al and published in Nature Medicine.

Copyright © 2023 Knowridge Science Report. All rights reserved.