After decades of scientific debate, scientists in Britain and Belgium believe they have figured out how brain cells die in Alzheimer’s disease, they report BBC.

In an article in the journal Science, researchers link abnormal proteins that accumulate in the brain to “necroptosis,” a form of cellular suicide.

The findings were described as “exciting” as they offer new ideas for treating the disease.

It is the loss of brain cells – neurons – that leads to the symptoms of Alzheimer’s disease, including memory loss.

Scientists knew that the brains of people with Alzheimer’s disease accumulate proteins called amyloid and tau, but researchers could not link all the key signs of the disease together.

• The reason for the progression of Alzheimer’s disease has been revealed

Researchers from the Dementia Research Institute at University College London in the UK and KU Leuven in Belgium say that abnormal amyloid starts to accumulate in the spaces between neurons, leading to brain inflammation that the neurons don’t like. This begins to change their internal chemistry.

Tau protein also appears, and brain cells begin to produce a specific molecule (called MEG3) that causes death through necroptosis.

Necroptosis is one of the methods our body normally uses to remove unwanted cells as new cells are produced.

The brain cells survived when the team was able to block MEG3.

“This is a very important and exciting discovery,” researcher Bart De Strooper, from the UK’s Dementia Research Institute, told the BBC.

“For the first time, we have a clue about how and why neurons die in Alzheimer’s disease. For 30-40 years there have been many assumptions, but no one has been able to determine the mechanisms.

“It really provides strong evidence that this is a specific pathway to suicide.”

The answers were obtained by experiments during which human brain cells were transplanted into the brains of genetically modified mice. The animals were programmed to produce large amounts of abnormal amyloid.

There have been recent advances in the development of drugs that remove amyloid from the brain, and there are the first treatments that slow the destruction of brain cells.

Professor De Strooper says the discovery that blocking the MEG3 molecule can prevent brain cell death could lead to “a whole new line of drug development”.

• Lilly’s donanemab slows Alzheimer’s disease by 60% in patients with mild Alzheimer’s disease – study