As people live longer their chances of developing Alzheimer’s disease also grows – however, researchers from UCLA have found that fish oils can really reduce your chances of developing Alzheimer’s. More importantly, they have found out why this is so.

You can read about this in the Journal of Neuroscience.

Greg Cole, professor of medicine and neurology, David Geffen School of Medicine, UCLA and associate director of UCLA’s Alzheimer Disease Research Center, and team say that omega-3 fatty acid docosahexaenoic acid (DHA), which is found in fish oil, raises the production of LR11. LR11 is a protein which exists at excessively low levels among Alzheimer’s disease patients. LR11 is known to destroy the protein that forms the plaques linked to the disease.

These plaques are deposits of beta amyloid, a protein that experts say is toxic to neurons in the brain – these deposits, as their numbers grow lead to Alzheimer’s. If high levels of LR11 protect people from developing Alzheimer’s, it is logical that levels that are too low will have the opposite effect.

Alzheimer’s is a devastating neurodegenerative disease that brings with it memory loss, dementia, personality change and eventually death. Approximately 5.1 million people in the USA suffer from Alzheimer’s disease, according to the national Alzheimer’s Association. The Association estimates that there may well be about 11 to 16 million sufferers by the middle of this century.

The scientists looked at the effects of fish oil, or its constituent DHA, in multiple biological systems and administered the oil or fatty acid by diet and by adding it directly to neurons cultivated in the lab.

Cole said “We found that even low doses of DHA increased the levels of LR11 in rat neurons, while dietary DHA increased LR11 in brains of rats or older mice that had been genetically altered to develop Alzheimer’s disease.”

To demonstrate that the benefits of DHA were not confined to nonhuman animal cells, the scientists also confirmed that DHA has a direct impact on human neuronal cells in culture as well. Consequently, elevated levels of DHA, which in turn lead to an abundance of LR11 appear to protect against Alzheimer’s disease, while low LR11 levels have the opposite effect as they allow the formation of the amyloid plaques.

Fish oil and its significant component, omega-3 fatty acids, have been a bastion of alternative health practitioners for years and have been sanctioned by the American Heart Association to decrease the chances of developing cardiovascular disease.

DHA is considered an ‘essential’ fatty acid because our bodies cannot make it from other sources – we have to obtain it though diet. DHA is the most abundant essential fatty acid in the brain, according to several studies, Cole explains – it is crucial for the healthy brain development of the fetus and infant. Studies have also indicated an association between low DHA levels with cognitive impairment. Low DHA levels have also been linked to raised oxidative stress in the Brains of patients with Alzheimer’s.

As a result of these findings, the National Institutes of Health (NIH) is currently carrying out a large-scale clinical trial with DHA in patients with established Alzheimer’s disease. For those patients it may be too late in Alzheimer’s progression for DHA to make much difference. However, Cole hopes trials are eventually conducted on patients who are in the earliest stages of Alzheimer’s. He doubts the pharmaceutical industry will carry out such trials as fish oils are abundantly available already.

We have yet to decide, says Cole “What the optimal dose should be. It could be that a smaller amount might be helpful, especially in a place like the south of France, where people are already on a Mediterranean diet.”

Perhaps the dose would need to be higher in the USA where fish consumption is comparatively low.

Cole said “There’s a deficiency of DHA to begin with. And this may contribute to the low LR11 seen in many Alzheimer’s patients.”

“Omega-3 Fatty Acid Docosahexaenoic Acid Increases SorLA/LR11, a Sorting Protein with Reduced Expression in Sporadic Alzheimer’s Disease (AD): Relevance to AD Prevention”
Qiu-Lan Ma, Bruce Teter, Oliver J. Ubeda, Takashi Morihara, Dilsher Dhoot, Michael D. Nyby, Michael L. Tuck, Sally A. Frautschy, and Greg M. Cole
The Journal of Neuroscience, December 26, 2007, 27(52):14299-14307
doi:10.1523/JNEUROSCI.3593-07.2007
Click here to view Abstract online

Written by – Christian Nordqvist