Pomegranates may improve memory in Alzheimer's patients

Forgetfulness, difficulty finding words and confusion about time and place are some of the most common symptoms of Alzheimer’s disease (AD), the most frequently occurring type of dementia. Now, researchers at the University of Copenhagen and the US National Institute on Aging have discovered that an ordinary fruit can help treat this incurable disease.

The researchers had previously discovered that a specific molecule, nicotinamide riboside (NAD supplement), plays a key role in neurodegenerative diseases such as Alzheimer’s and Parkinson’s, as it actively helps remove damaged mitochondria from the brain.

“Many patients with neurodegenerative diseases experience mitochondrial dysfunction, also known as mitophagy,” explained Vilhelm Bohr, an Affiliate Professor at the University of Copenhagen and previously Department Chair at the National Institute on Aging.

“This means that the brain has difficulties removing weak mitochondria, which thus accumulate and affect brain function. If you are able to stimulate the mitophagy process, removing weak mitochondria, you will see some very positive results.”

The team has now shown that a substance found in pomegranates, strawberries and walnuts, called urolithin A, removes weak mitochondria from the brain just as effectively as NAD supplement. The results of their latest study, published in the journal Alzheimer’s & Dementia, found that long-term urolithin A treatment significantly improved learning, memory and olfactory function in AD transgenic mice.

“Even though the study was conducted on mouse models, the prospects are positive,” Bohr said. “So far, research has shown promising results for the substance in the muscles, and clinical trials on humans are being planned.”

The researchers still don’t know how much urolithin A is needed to improve memory and alleviate symptoms of Alzheimer’s, with Bohr noting, “I imagine that it is more than a pomegranate a day. However, the substance is already available in pill form, and we are currently trying to find the right dosage.”

He also hopes the substance can be used for preventative purposes with no significant side effects.

“The advantage of working with a natural substance is the reduced risk of side effects,” he said. “Several studies so far show that there are no serious side effects of NAD supplementation. Our knowledge of urolithin A is more limited.

“Clinical trials with urolithin A have been effective in muscular disease, and now we need to look at Alzheimer’s disease.”

Illustration: KU.