London, Feb 13 (IANS): Researchers have identified a drug that can cut the risk of developing Alzheimer's disease by targeting the first step in the toxic chain reaction leading to the death of brain cells.

The drug called bexarotene, which revealed the potential to delay the onset of Alzheimer's disease, has raised the possibility that other molecules like it can be used to reduce the risk of developing Alzheimer's disease, the researchers said.

"The body has a variety of natural defences to protect itself against neuro-degeneration but as we age, these defences become progressively impaired and can get overwhelmed," said Michele Vendruscolo, professor at the University of Cambridge. 

The researchers in the study, published in the journal Science Advances, assembled a library of more than 10,000 small molecules which interact in some way with amyloid-beta, a molecule that plays a vital role in Alzheimer's disease.

Using a new test, they were able to determine what happens during each stage of Alzheimer's development and also what might happen if one of those stages was somehow switched off.

By analysing the way the drug works at the molecular level, the researchers found that bexarotene stops the first step in the molecular cascade that leads to the death of brain cells. 

Over the next 35 years, the number of people with Alzheimer's disease is predicted to go from 40 million to 130 million, with 70 percent of those in the middle or low-income countries, the researchers concluded.