Chemicals naturally occurring in green tea and red wine can actually put a stop to the process that leads to brain damage in Alzheimer’s disease, according to a study conducted by researchers from the University of Leeds and published in the Journal of Biological Chemistry.
“This is an important step in increasing our understanding of the cause and progression of Alzheimer’s disease,” lead researcher Nigel Hooper said.
Alzheimer’s disease is the most common form of dementia. It is an incurable, degenerative disease marked by progressive cognitive decline, including a loss of memory and daily functioning.
“It’s a misconception that Alzheimer’s is a natural part of aging,” Hooper said.
Instead, the disease occurs when a type of protein known as amyloid builds up in the brain, forming sticky clumps in a variety of different shapes. When these clumps attach to the proteins on a brain cell, those proteins malform (becoming a type of defective, infectious protein known as a prion) and the cells die.
Prior studies have linked EGCG, a chemical found in green tea, and resveratrol, a chemical found in red wine, with a lower risk of dementia and with higher cognitive function at later ages. More recently, they have been shown to change the shape of amyloid proteins.
“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,” co-author Jo Rushworth said. “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.”
Amyloid disrupted, brain cells protected
The researchers exposed human and animal brain cells in the laboratory to artificially produced amyloid clusters. For the first time, they demonstrated “that when amyloid balls stick to prion, it triggers the production of even more amyloid, in a deadly vicious cycle,” Hooper said.
When the tea and wine extracts were introduced early in the process; however, the researchers found that the shape of the amyloid clusters was disrupted.
“The amyloid balls no longer harmed the nerve cells,” Hooper said.
The results were hailed by Simon Ridley, head of research at Alzheimer’s Research UK, one of the study’s founders.
“Understanding the causes of Alzheimer’s is vital if we are to find a way of stopping the disease in its tracks,” Ridley said. “With half a million people affected by Alzheimer’s in the UK, we urgently need treatments that can halt the disease – that means it’s crucial to invest in research to take results like these from the lab bench to the clinic.”
Resveratrol and EGCG have been linked to many of the observed health benefits of red wine and green tea, respectively. Resveratrol is also found in peanuts.
Encouragingly, a study published in the journal Phytomedicine in 2011 found that the antioxidants found in green tea are actually more effective at protecting against Alzheimer’s and dementia when digested by the body first.