Billions have been spent on research that might lead to new drugs for treating Alzheimer’s, but while substantial progress has been made, there’s not much yet in the way of a cure. But one new study suggests that dieting may be an important factor for managing the neurodegenerative disease’s symptoms. According to the findings, chemical compounds typically found in green tea and carrots reversed Alzheimer’s-like symptoms in mice.
“You don’t have to wait 10 to 12 years for a designer drug to make it to market; you can make these dietary changes today,” said senior author Terrence Town, a professor of physiology and neuroscience at the University of Southern California. “I find that very encouraging.”
Town and colleagues focused on two compounds: EGCG ( epigallocatechin-3-gallate), one of the main ingredients of green tea, and FA (ferulic acid), commonly found in carrots, tomatoes, rice, wheat, and oats. The researchers randomly assigned 32 mice, which were genetically modified to have Alzheimer’s, to one of four groups, divided into an equal number of males and females. For three months, mice were given a combination of EGCG and FA, either EGCG or FA only, or a placebo — yes, rodents also have the placebo effect. Additionally, a group of healthy mice provided baseline performance for Alzheimer’s-free symptoms.
Before and after the three-month diet, the rodents were subjected to a barrage of tests that gauged their thinking and memory skills. One such test involves a Y-shape maze in order to assess a mouse’s spatial working memory, which is key to finding your way out of a building.
A healthy mouse will explore each arm of the Y maze in search of food or a way out. They will enter the three arms in sequence more often than by chance alone. But rodents with Alzheimer’s-like symptoms don’t do this as well because their spatial memory is impaired, making them more likely to explore the same arm twice.
“After three months, combination treatment completely restored spatial working memory and the Alzheimer’s mice performed just as well as the healthy comparison mice,” Town said.
Alzheimer’s disease is widely believed to be caused by the accumulation of beta-amyloid proteins which clump together to form plaques between neurons and disrupt cell function. Another physical characteristic of the Alzheimer’s diseased brain is the buildup of tau proteins, which tangle inside neurons, blocking their transport system. Town suspects that the compounds prevent bigger amyloid proteins from breaking up into smaller amyloid beta proteins that clog neurons. They may also reduce neuroinflammation and oxidative stress in the brain, both important aspects of Alzheimer’s pathology.
But while the study is exciting, its findings apply to mice and most such discoveries never translate into human treatments. Even so, green tea and carrots are harmless and there’s nothing to stop people from including them in their diet. In the future, Town wants to explore this combination treatment further.
The findings appeared in the Journal of Biological Chemistry.