Jyotirmaya Behera states “Our findings suggest that dietary administration of garlic containing allyl sulfide could help maintain healthy gut microorganisms and improve cognitive health in the elderly.” Findings will be presented at the American Physiological Society’s annual meeting in Florida.
“The diversity of the gut microbiota is diminished in elderly people, a life stage when neurodegenerative diseases such as Alzheimer’s and Parkinson’s develop and memory and cognitive abilities can decline,” explains Neetu Tyagi, PhD “We want to better understand how changes in the gut microbiota relate to aging-associated cognitive decline.”
24 month old mice were given allyl sulfide orally which were compared to mice that were 4 and 24 months old that had not received the dietary supplement. The older mice receiving the supplement were observed to show better long and short term memory as well as healthier gut bacteria than those that did not get the supplement. 24 month old mice that did not get the supplement also had impaired spatial memory.
Reduced gene expression of neuronal derived natriuretic factor in the brain was revealed to likely be responsible for the cognitive decline in further investigations; the NDNF gene was recently discovered by University of Louisville researchers and to be required for both long and short term memory consolidation.
Animals receiving allyl sulfide were found to exhibit higher levels of NDNF gene expression; recombinant NDNF protein therapy in the brain was observed to restore cognitive abilities of the older mice who had not received the supplement. Administration of allyl sulfide orally was found to produce hydrogen sulfide gas which is a messenger molecule that prevents intestinal inflammation in gut lumen.
Findings suggest dietary allyl sulfide promotes memory consolidation by restoring gut bacteria, Additional investigations are being conducted to gain better understandings on the relationship between gut microbiota and cognitive decline; and how garlic might be used to treat the aging human population.