HMM: Environmental toxin linked to dementia, study shows.

Chronic exposure to a toxin found in some lakes and desert topcrusts contributes to neurological problems commonly associated with ALS, Alzheimer’s and other neurodegenerative diseases, a new study shows – but at least in certain animals the damage appeared to be offset by increasing an amino acid in the diet.

The study, published Wednesday by the Royal Society of London, found that vervets chronically exposed to the neurotoxin BMAA developed neurofibrillary tangles and amyloid plaque deposits in the brain.

The finding stunned researchers, who were looking for preliminary signs of disease, but were not expecting to find advanced tangles and plaques.

“They looked identical to what you see in Alzheimer’s Disease, to the point that Dr. Robert Switzer (one of the neuropatholigists) mistakenly thought we had been looking at Alzheimer’s slides,” said Paul Alan Cox, the study’s lead author and an ethnobotanist at the Institute for Ethnomedicine in Jackson Hole, Wyoming. “No-one had seen tangles in an animal before…and the higher the exposure, the denser the tangles.”

But wait, there’s more:

The study also found that feeding the dietary amino acid L-serine to the vervets significantly reduced the number of tangles in their brains. Further human trials are underway to determine whether L-serine could help prevent cognitive impairment.

What you’d like to take from this is that dosing with L-serine would prevent Alzheimer’s, which would be great, especially as L-serine is cheap and readily available. But while that’s an appealing hypothesis, it may not turn out to be that simple.