Natural chemicals found in green tea and red wine may disrupt a key step in the Alzheimer’s disease pathway, according to new research.
Researchers from the University of Leeds said they have identified the process, or disease pathway, that allows harmful clumps of protein to latch on to brain cells, causing them to die. They were then able to interrupt this pathway using the purified extracts of EGCG from green tea and resveratrol from red wine.
“This is an important step in increasing our understanding of the cause and progression of Alzheimer’s disease,” said lead researcher Professor Nigel Hooper of the University’s Faculty of Biological Sciences.
“It’s a misconception that Alzheimer’s is a natural part of aging. It’s a disease that we believe can ultimately be cured through finding new opportunities for drug targets like this.”
Alzheimer’s is characterized by a build-up of amyloid protein in the brain, which clumps together to form toxic, sticky balls of varying shapes.
These balls latch on to the surface of nerve cells in the brain by attaching to proteins on the cell surface called prions, causing the nerve cells to malfunction and eventually die, researchers explain.
“We wanted to investigate whether the precise shape of the amyloid balls is essential for them to attach to the prion receptors, like the way a baseball fits snugly into its glove,” said co-author Dr. Jo Rushworth. “And if so, we wanted to see if we could prevent the amyloid balls binding to prion by altering their shape, as this would stop the cells from dying.”
The team formed amyloid balls in a test tube and added them to human and animal brain cells.
“When we added the extracts from red wine and green tea, which recent research has shown to re-shape amyloid proteins, the amyloid balls no longer harmed the nerve cells,” said Hooper.
“We saw that this was because their shape was distorted, so they could no longer bind to prion and disrupt cell function. We also showed, for the first time, that when amyloid balls stick to prion, it triggers the production of even more amyloid, in a deadly vicious cycle.”
The research team’s next steps are to understand exactly how the amyloid-prion interaction kills off neurons, according to Hooper.
“I’m certain that this will increase our understanding of Alzheimer’s disease even further, with the potential to reveal yet more drug targets,” he said.
The study, funded by the Wellcome Trust, Alzheimer’s Research UK and the Medical Research Council, was published in the Journal of Biological Chemistry.
Source: University of Leeds