Animals fed the nutrient mix performed better in maze tests than animals not fed the combination, a result attributed to improved cognitive function, according to results published in the Federation of American Societies of Experimental Biology (FASEB) journal .
Researchers from MIT are now taking the research a step further and have are exploring the potential of a beverage-based prevention for Alzheimer's and other brain diseases.
"It may be possible to use this [combination] to partially restore brain function in people with diseases that decrease the number of brain neurons, including, for example, Alzheimer's disease, Parkinson's, strokes and brain injuries.
Of course, such speculations have to be tested in double-blind, placebo-controlled clinical trials," said senior author Richard Wurtman.
Trials are reportedly underway in Europe, and preliminary results have been submitted to the Alzheimer's Association International Conference on Alzheimer's Disease, to be held in Chicago at the end of this month.
Don't forget the gerbils Wurtman and co-workers supplemented the diets of gerbils with uridine (in its monophosphate form, 0.5 per cent) and choline (0.1 per cent), and docosahexaenoic acid (DHA, 300 mg/kg/day) for four weeks.
DHA is an omega-3 fatty acids obtained predominantly from marine sources.
Choline is found in meats, nuts and eggs, and can also be made by the body.
Uridine, on the other hand, is contained in breast milk and synthesized by the body - it cannot be obtained from food sources, however.
At the end of the study, significant increases in phospholipid levels in the brain were observed when the compounds were given together, while administration of only DHA or UMP or UMP plus choline produced smaller increases.
When the animals were subjected to different maze tests, the combination of supplements produced the best results, indicating enhanced cognitive function.
Sparking the connections The MIT researchers report that the benefits of the combination are due to the restoration of synapses, where information is passed between neurons.
These play a critical role in learning and memory.
All three dietary supplements used in the study are precursors to the fatty molecules that make up cell membranes, including the membranes of brain cells, which form synapses.
The researchers report that gerbils that received all three supplements had as much as 70 per cent more phospholipids in the cell membranes than control animals, suggesting the formation of new synapses.
"The improvements in cognition observed in normal gerbils in this study and in rats with impaired cognition, in a previous study, correlate perfectly with the evidence of increased brain synapses, as shown biochemically and anatomically," said Wurtman.
"This suggests that treating the animals with the experimental mixture affects behavior by increasing the number of synapses in important brain regions."
For the preliminary results of the clinical trial, we must await the end of the month to discover if similar benefits can be repeated in humans.
The research was funded by the National Institutes of Health and the CBSMCT.
Source: FASEB Journal Published online ahead of print 7 July 2008, doi:10.1096/fj.08-112425 "Dietary uridine enhances the improvement in learning and memory produced by administering DHA to gerbils" Authors: S. Holguin, J. Martinez, C. Chow, R. Wurtman