In early-stage laboratory experiments, the researchers identified the process which allows harmful clumps of protein to latch on to brain cells, causing them to die. They were able to interrupt this pathway using the purified extracts of EGCG from green tea and resveratrol from red wine.
The findings, published in the Journal of Biological Chemistry, offer potential new targets for developing drugs to treat Alzheimer's disease, which affects some 800,000 people in the UK alone, and for which there is currently no cure.
"This is an important step in increasing our understanding of the cause and progression of Alzheimer's disease," says 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 ageing; it's a disease that we believe can ultimately be cured through finding new opportunities for drug targets like this."
Alzheimer's disease is characterised by a distinct build-up of amyloid protein in the brain, which clumps together to form toxic, sticky balls of varying shapes. These amyloid 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.
"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," says 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. Professor Hooper said: "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. 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," he added.
Professor Hooper says that the team's next steps are to understand exactly how the amyloid-prion interaction kills off neurons. "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.
Dr Simon Ridley, Head of Research at Alzheimer's Research UK, the UK's leading dementia research charity, which part-funded the study, said: "Understanding the causes of Alzheimer's is vital if we are to find a way of stopping the disease in its tracks. While these early-stage results should not be a signal for people to stock up on green tea and red wine, they could provide an important new lead in the search for new and effective treatments. 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."
The research was funded by the Wellcome Trust, Alzheimer's Research UK and the Medical Research Council.
Jessica Kwok and Ronaldo Ichiyama, International Spinal Research Trust (Feb 2018), £94,450
Dave Lewis and Colleagues in South Africa, HEFCE Global Challenge Research (Jan 2018), £48,000
Sarah Calaghan, Ed White, John Colyer, Isuru Jayasinghe, BHF (Jan 2018), £128,308
Christine Foyer and Alison Baker, HEFCE GCRF Grant (Jan 2018), £71,158
Alison Baker, Yun Yung Gong and Lindsay Stringer and ICRISAT India, HEFCE GCRF Grant (Jan 2018), £27,000
Graham Askew, Simon Walker, BBSRC (Jan 2018), £699,781
Jennifer Tomlinson, Royal Society (Jan 2018), £512,801
Alison Dunn, NERC (Dec 2017), £18,000
Jennifer Tomlinson, Royal Society-Research Fellows Enhancement Award (Dec 2017), £94,681
Helen Miller, AB AGri Grant (Dec 2017), £73,600
Simon Walker, Royal Society Enhancement Award (Dec 2017), £10,000
Carrie Ferguson, Bryan Taylor, Harry Rossiter, The Physiological Society (Dec 2017), £7,392
Ralf Richter, Royal Society (Dec 2017), £6,000
Christine Foyer, British Council Newton Fund (Dec 2017), £49,840
Adrian Whitehouse and colleagues in School of Chemistry and University of Liverpool, MRC (Nov 2017), £622,319
Michelle Peckham, Neil Ransom, MRC (Nov 2017), £495,159
Dave Lewis, British Council India (Nov 2017), £22,540
Hannah Dugdale, Royal Society (Nov 2017), £15,000
Elton Zeqiraj, Royal Society (Nov 2017), £15,000
Shaunna Burke, Cancer Research UK Innovation Grant (Nov 2017), £20,000
Alex O'Neill and colleagues in Chemistry, BBSRC (Nov 2017), £431,865
Jessica Kwok, Wings for Life (Nov 2017), £87,365
Tom Bennett, BBSRC (Oct 2017), £523,679
Neil Ranson, Darren Tomlinson, BBSRC (Oct 2017), £494,318
Nikita Gamper, BBSRC (Oct 2017), £490,426
Amanda Bretman and colleagues from UEA, NERC (Oct 2017), £430,886
Juan Fontana, Rosetrees Trust consumables grant (Oct 2017), £22,500
Helen Miller, DSM Nutritional Products AG (Sep 2017), £69,988
Neil Ranson, Juan Fontana, Mark Harris, Michelle Peckham, Ralf Richter, Peter Stockley, Patricija Van Oosten-Hawle and colleagues in Engineering, FMH and MAPS, Wellcome Trust Equipment Call (Sep 2017), £418,000
Jamie Johnston, Physiological Society (Sep 2017), £10,000
Frank Sobott, Adrian Goldman, Mark Harris, Andrew Macdonald, Stephen Muench, Sheena Radford and colleagues in FMH and MAPS, Wellcome Trust Equipment Call (Aug 2017), £415,000
Ralf Richter, David Brockwell, Eric Hewitt, Jessica Kwok, Emanuele Paci and MAPS/FMH, BBSRC (Jun 2017), £600,000
Eric Blair, Adrian Whitehouse, Nicola Stonehouse, Alison Baker, Richard Bayliss, Joan Boyes, Ryan Seipke, Sally Boxall and MAPS/FMH, BBSRC (Jun 2017), £376,000
Stefan Kepinski, Yoselin Benitez-Alfonso, Tom Bennett, Michelle Peckham, BBSRC (Jun 2017), £331,000
Roman Tuma, Lars Jeuken, Paul Millner, Sheena Radford, Peter Stockley and MAPS/FMH, BBSRC (Jun 2017), £222,000
Vas Ponnambalam, Darren Tomlinson, Stephen Wheatcroft, BHF (May 2017), £107,878
Graham Askew in collaboration with Bangor University, BBSRC (Mar 2017), £477,383
Stephen Muench, BBSRC (Mar 2017), £132,945
Nic Stonehouse, MRC (Mar 2017), £906,341
Bill Kunin, Steve Sait, BBSRC (Mar 2017), £602,831
Adrian Goldman, EU (Mar 2017), £546,576
Sheena Radford, Wellcome Trust (Mar 2017), £1,836,482
Tom Bennett, Royal Society (Mar 2017), £15,000
Jamie Johnston, Royal Society (Mar 2017), £15,000
Beatrice Filippi, Royal Society (Mar 2017), £15,000