Alzheimer: Mystery of Dying Brain Cells Solved
About 55 million people live with dementia worldwide.
About 55 million people live with dementia worldwide. New research into why brain cells die is enabling scientists to develop effective Alzheimer drugs.Worldwide about 55 million people live with some form of dementia — of which Alzheimer's is just one such disease.
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Two-thirds of people with dementia live in developing countries. And as the global population ages, it is estimated that the number of dementia cases will grow to about 139 million by the year 2050. People in China, India, Latin America and Sub-Saharan Africa are likely to be worst hit.
Researchers have been looking for medical treatments for Alzheimer's for decades. But their successes have been limited so far.
There has been new hope, however, since the discovery of an active agent called Lecanemab. The drug was approved for use by the US Food and Drug Administration in 2023 and shows signs that it slows the development of Alzheimer's in its early stages.
Complex processes in the brain
It's been difficult to develop medicines against Alzheimer's because researchers have yet to fully understand what happens in the brain when the disease takes hold.
One of the most pressing questions is why brain cells die.
Researchers know that amyloid and tau proteins develop in the brain, but until recently, they did not know how the two proteins function together and how they influence cell death.
But researchers based in Belgium and the UK say they can explain what's happening now.
Mystery of cell death solved
According to a study, published in the journal Science, the researchers say there is a direct connection between these abnormal proteins — amyloid and tau — and what's called necroptosis — or cell death.
Cell death usually happens as an immune response to infection or an inflammation and rids the body of undesirable cells. That enables new, healthy cells to grow.
When the supply of nutrients collapses, the cells swell up, and that destroys a plasma membrane. The cells gets inflamed and dies off.
In the study, the researchers suggest that cells in Alzheimer's patients get inflamed when amyloid protein gets into neurons in the brain. That changes the internal chemistry of the cells.
The amyloid clumps together into so-called plaques, and the tau protein, which is fiber-like, forms its own bundles, known as tau tangles.
When these two things happen, the brain cells produce a molecule called MEG3.
The researchers attempted to block MEG3 and that said that when they were able to block it, the brain cells survived.
To do this, the researchers transplanted human brain cells into the brains of genetically modified mice, which produced a large amount of amyloid.
One of the researchers, Bart De Strooper of the Dementia Research Institute in the UK, said it was the first time — after 30-40 years of speculation — that scientists had found a possible explanation for cell death in Alzheimer's patients.
Hope for new medicines
The researchers, based at KU Leuven in Belgium and the Dementia Research Institute of University College London, said they hope their findings will help in the discovery of new medical treatments for Alzheimer's patients.
Their hope is not without good reason: the drug Lecanemab specifically targets the protein amyloid. If its possible to block the MEG3 molecule, medicine may manage to stop cell death in the brain altogether.
This article was originally published in German.
(The above story first appeared on LatestLY on Sep 21, 2023 06:40 PM IST. For more news and updates on politics, world, sports, entertainment and lifestyle, log on to our website latestly.com).