The role of n-3 dietary polyunsaturated fatty acids in brain function and ameliorating Alzheimer's disease: Opportunities for biotechnology in the development of nutraceuticals

Prospective epidemiological surveys and numerous animal studies have shown an important role for dietary docosahexaenoic acid (DHA) in healthy brain function and reducing the risk of dementia. The evidence for this is summarised and some further experiments of our own are described. For the experimentation we have used the Tg2576 mouse, which is a well known model of amyloid pathology and cognitive impairment as seen in Alzheimer's disease. We found that, while brain levels of DHA showed a positive correlation with behaviour and a negative correlation with insoluble beta-amyloid (1-40), the general benefits of DHA-enriched diets were not as great as have sometimes been reported in the literature. This may be due to either the age of the animals we tested and/or the fact that we examined the effects of DHA supplementation against a normal healthy control diet condition, unlike previous studies, in order to mimic dietary supplement use in the human population. In addition, we point to some ways in which biotechnology could be used to supplement the world's supply of omega-3 PUFAs (especially DHA) since there is an increasing shortage of such compounds for dietary consumption. (C) 2011 Elsevier Ltd. All rights reserved.