A reduction in the ability to protect oneself from inflammation and oxidative damage can result in degenerative brain diseases, as well as heart disease and other disorders, notes Dr Poulose. In previous research conducted by Dr Poulose and laboratory director James Joseph, PhD, aged rats given diets that contained 2 percent strawberry, blueberry or blackberry extract for two months experienced a reversal in the age-associated decline in nerve function and behavior that results in impairment of memory and learning. "The good news is that natural compounds called polyphenolics found in fruits, vegetables and nuts have an antioxidant and anti-inflammatory effect that may protect against age-associated decline," Dr Poulose remarked.
For the current research, the duo studied the brain's natural "house-cleaning" process, which involves autophagy by cells known as microglia. These cells remove and recycle toxic proteins that can interfere with brain function. "In aging, microglia fail to do their work, and debris builds up," Dr Poulose explained. "In addition, the microglia become over-activated and actually begin to damage healthy cells in the brain."
In experiments with cultured mouse cells, Dr Poulose found that blueberry and strawberry extracts inhibited a protein that interferes with autophagy. "The results strongly suggest that the benefits of both berries extend beyond the antioxidant and anti-inflammatory effects to cellular toxic clearance through induction of autophagy in brain," concludes a written summary of the findings.
Dr Poulose commented that the study adds evidence to the benefits of consuming polyphenolic-rich foods, including berries and walnuts. "Our research suggests that the polyphenolics in berries have a rescuing effect," he stated. "They seem to restore the normal housekeeping function. These findings are the first to show these effects of berries."
