Fish Oil Prevents Alzheimer's Plaques

January 11, 2008

Brain Needs Fish Oil Fatty Acid to Make Plaque-Fighting Protein

It's known that people who get plenty of DHA, one of the two main fish oil fatty acids, have a reduced risk of Alzheimer's disease, notes Greg M. Cole, PhD, associate director of the UCLA Alzheimer's Disease Research Center. Dr. Cole with other UCLA researchers has found that your brain needs DHA- the fish oil fatty acid, to make a plaque-fighting protein. People with Alzheimer's disease tend to have low levels of a brain protein called LR11 (also known as SorLA). Additionally, about 15% of people with Alzheimer's disease carry a genetic mutation that reduces production of LR11. LR11 helps clear the brain of the precursor protein for amyloid, and amyloid is essential for production of the brain-destroying A-Beta plaque (also known as beta-amyloid plaque) that clogs the brains of people with Alzheimer's disease.

Sure enough, in live rodents and in cultures of human brain cells, the researchers found that the fish-oil compound DHA causes brain cells to make lots more LR11. "Because reduced LR11 is known to increase beta amyloid production and may be a significant genetic cause of late-onset Alzheimer's disease, our results indicate that DHA increases in LR11 levels may play an important role in preventing late-onset Alzheimer's disease," Dr. Cole and his colleagues conclude. It may be too late for people with late-stage Alzheimer's disease to get much benefit from fish oil. But Dr. Cole suggests that it may be a great help if taken at the first signs of Alzheimer’s disease. The UCLA scientists report their findings in the Dec. 26, 2007 issue of The Journal of Neuroscience.

More evidence that the omega-3 fatty acid DHA may help prevent and fight Alzheimer's disease

In the brain of someone with Alzheimer's disease there are tangles of twisted fibers and clumps of proteins along with massive levels of free radical production and also signs of inflammation. These protein clumps based on beta-amyloid protein are connected to brain nerve cell death, the hallmark of this disease. This leads to personality changes, severe progressive memory loss and eventually death.

DHA is an omega-3 fat found in ocean going fish and seafood. Researchers at Louisiana State University's Neuroscience center of Excellence found that DHA helped brain cells in two ways:

1) Inhibiting the production of beta-amyloid proteins, the protein found in Alzheimer's brain plaques

2) Boosting the production of a protein known as NPD1. This protein protects brain cells and helps them stay alive.

The study is published in the September 8th, 2005 issue of The Journal of Clinical Investigation. Note: for more information on DHA and Alzheimer's disease see our radio studies for March 24th, 2005.