How Pomegranates Help Fight Alzheimer's Disease
Perhaps you have heard from previous studies that pomegranates have been found to help protect against Alzheimer’s disease. Now scientists involved in new research have identified which compounds in this fruit seem to be behind this benefit.
The authors of several earlier research efforts have reported how compounds found in the hard-rind fruit pomegranate possess neuroprotective properties. Among them is an animal study appearing in Current Alzheimer’s Research, in which experts demonstrated that pomegranate extract changed levels and ratios of amyloid-beta peptides, which supports a reduction in the development of Alzheimer’s disease.
Accumulation of amyloid-beta protein in the brain is one of the characteristics of Alzheimer's disease. Among the numerous research efforts underway are those attempting to prevent, reduce, or eliminate buildup of these substances.
In the animal study, the authors noted that their findings supported a specific mechanism in pomegranate extract that fights the production of amyloid-beta. Another study appearing at the same time noted that compounds in pomegranate inhibit the formation of advanced glycation endproducts, substances that play a key role in the development of Alzheimer’s.
New pomegranate and Alzheimer’s study
In the latest study, researchers have identified what they believe are the compounds in pomegranates that possess anti-Alzheimer’s effects. To make that determination, the authors evaluated 21 isolated components from pomegranate extract, most of which were polyphenols called ellagitannins, and their metabolites called urolithins, which are produced when bacteria in the gut metabolize the polyphenols in pomegranate extract.
The researchers discovered that only the urolithins were able to penetrate the blood-brain barrier. To fight the formation of amyloid-beta, it’s necessary for a substance to pass through the blood-brain barrier, which suggests urolithins could have a role in treatment of Alzheimer's disease.
Urolithins have anti-inflammatory and neuroprotective properties. The researchers showed that these products of gut bacteria can reduce amyloid-beta levels and that they also increased the lifespan of an animal model of Alzheimer’s disease.
Further studies of the benefits of pomegranate extract in the fight against Alzheimer’s disease are needed to refine the protective benefits and determine exactly how compounds from this fruit may help prevent or treat this devastating disease.
Ahmed AH et al. Pomegranate extract modulates processing of amyloid-B precursor protein in an aged Alzheimer’s disease animal model. Current Alzheimer’s Research 2014; 11(9): 834-43
Liu W et al. Pomegranate phenolics inhibit formation of advanced glycation endproducts by scavenging reactive carbonyl species. Food & Function 2014 Nov; 5(11): 2996-3004
Yuan T et al. Pomegranate’s neuroprotective effects against Alzheimer’s disease are mediated by urolithins, its ellagitannin-gut microbial derived metabolites. ACS Chemical Neuroscience 2015 Nov 17