Green vegetables are commonly associated as an essential part of a healthy diet, but new research from the University of South Florida has found that basil and other herbs may protect the brain against Alzheimer’s disease pathology.
The study was based around investigation of the gut microbiome, discovering within it a sense mechanism that explains why fenchol – a natural compound abundant in basil plants – can reduce brain neurotoxicity that leads to Alzheimer’s.
However, the correlation is not direct. The study’s results first demonstrated that short-chain fatty acids (SCFAs), metabolites produced in the gut microbiome that provide nutrition for colon cells, also contribute to brain health. SCFA activity is largely reduced in older patients with Alzheimers.
The protective effects are produced when the short-chain fatty acids bind to and activate the fatty acid receptor 2 (FFAR2). The researchers have discovered that the fenchol found in basil is excellent at triggering this biological communication.
“Our study is the first to discover that stimulation of the FFAR2 sensing mechanism by these microbial metabolites (SCFAs) can be beneficial in protecting brain cells against the toxic accumulation of the amyloid-beta (Aβ) protein associated with Alzheimer’s disease,” said principal investigator Hariom Yadav.
The fenchol-rich basil plant was discovered as an appropriate candidate for mimicking the beneficial signaling through a large-scale screening process concerning over 144,000 natural compounds. The results narrowed the range down to just 15 leading candidates, with fenchol showing the highest amount of potential for the stimulation of FFAR signalling.
Upon discovering this, the researchers closely examined the compound, discovering that it decreases senescent neuronal cells (otherwise known as ‘zombie cells’) that are commonly located in brains with Alzheimers. These are cells that build up in aging organs to create an inflammatory environment, sending stress signals that ultimately spread the characteristic to otherwise healthy cells.
“Fenchol actually affects the two related mechanisms of senescence and proteolysis,” explained Yadav. “It reduces the formation of half-dead zombie neuronal cells and also increases the degradation of (nonfunctioning) Aβ, so that amyloid protein is cleared from the brain much faster.”
The discovery shows great potential for the future prevention of Alzheimers, but further research is still required. It is unclear whether concentrated doses of fenchol should be administered as a pill, or if regular consumption of plants such as basil would be sufficient.
“We also want to know whether a potent dose of either basil or fenchol, if it could be delivered by nasal spray, would be a quicker way to get the compound into the brain,” explained Yadav.
The study has published in the Frontiers in Aging Neuroscience.