Washington, Apr 18 (ANI): A new study has found that a type of omega-3 fatty acid, docosahexaenoic acid (DHA) may slow the growth of two brain lesions that are hallmarks of Alzheimer’s disease. The most widely available source of DHA is cold water oily fish such as wild salmon, herring, mackerel, anchovies and sardines.

The study was conducted by UC Irvine scientists under lead author Kim Green and was co-authored by Frank LaFerla.

As part of the study, researchers studied the effects of DHA in three test groups of mice bred to develop the plaques and tangles associated with Alzheimer’s disease. Mice in the control group were given food that mimics a typical American diet, with the ratio of omega-6 fatty acids to omega-3 fatty acids being 10:1. Studies indicate that a proper ratio is important to maintain health, with the ideal being 3:1 to 5:1. Typical Western diets contain unhealthy ratios ranging from 10:1 to 30:1. Omega-6 fatty acids are found in corn, peanut and sunflower oils.

The mice were given food with a 1:1 ratio of omega-6 fatty acids to omega-3 fatty acids. One of these groups received supplemental DHA only, and two groups received DHA plus additional omega-6 fatty acids. After three months, mice in all of the test groups had lower levels of beta amyloid and tau than mice in the control group, but at nine months, only mice on the DHA diet had lower levels of both proteins.

Researchers found that DHA works better on its own than when paired with omega-6 fatty acids.

The study also determined the mechanism by which DHA leads to lower levels of beta amyloid. DHA, they found, leads to lower levels of presenilin, an enzyme responsible for cutting beta amyloid from its parent, the amyloid precursor protein. Without presenilin, beta amyloid cannot be generated. When clumped into plaques, beta amyloid disrupts communication between cells and leads to symptoms of Alzheimer’s disease. “We are greatly excited by these results, which show us that
simple changes in diet can positively alter the way the brain works and lead to protection from Alzheimer’s disease pathology,”
Frank LaFerla said.

Researchers also found that stress hormones appear to rapidly exacerbate the formation of plaques and tangles, suggesting that managing stress could slow the progression of Alzheimer’s. “Combined with mental stimulation, exercise, other dietary
intakes, and avoiding stress and smoking, we believe that people can significantly improve their odds against this disease,” Kim
Green said.

The findings of the research were published in the April issue of The Journal of Neuroscience. (ANI)