Choline intake improves memory and attention-holding capacity

An experimental study in rats has shown that consuming choline, a vitamin B group nutrient found in foodstuffs like eggs and chicken or beef liver, soy and wheat germ, helps improve long-term memory and attention-holding capacity. The study, conducted by scientists at the University of Granada (Spain) Simón Bolívar University, (Venezuela) and the University of York (United Kingdom), has revealed that choline is directly involved in attention and memory processes and helps modulate them.

Researchers studied the effects of dietary supplements of choline in rats in two experiments aimed at analysing the influence of vitamin B intake on memory and attention processes during gestation and in adult specimens.

In the first experiment, scientists administered choline to rats during the third term of gestation in order to determine the effect of prenatal choline on the memory processes of their offspring. Three groups of pregnant rats were fed choline-rich, standard or choline-deficient diets. When their offspring had reached adult age, a sample of 30 was selected: 10 were female offspring of dams fed a choline-supplement, 10 had followed a choline-deficient diet and the other 10, a standard diet, acting as a control group.

Long-term memory

This sample of adult offspring underwent an experiment to measure their memory retention: 24 hours after being shown an object all the offspring (whether in the choline-supplement group or not) remembered it and it was familiar to them However, after 48 hours, the rats of dams fed a prenatal choline-rich diet recognized the object better than those in the standard diet group, while the choline-deficient group could not recognize it. Thus, the scientists concluded that prenatal choline intake improves long-term memory in the resulting offspring once they reach adulthood.

In the second experiment, the researchers measured changes in attention that occurred in adult rats fed a choline supplement for 12 weeks, versus those with no choline intake. They found that the rats which had ingested choline maintained better attention that the others when presented with a familiar stimulus. The control group, fed a standard diet, showed the normal learning delay when this familiar stimulus acquired a new meaning. However, the choline-rich intake rats showed a fall in attention to the familiar stimulus, rapidly learning its new meaning.

The study has been undertaken by University of Granada Department of Experimental Psychology researchers Isabel De Brugada-Sauras and Hayarelis Moreno-Gudiño (also on the research staff of Simón Bolívar University together with Diamela Carias); Milagros Gallo-Torre, researcher in the University of Granada Department of Psychobiology and Director of the “Federico Olóriz” University Research Institute for Neuroscience; and Geoffrey Hall, of the Department of Psychology of the University of York. Their study has recently given rise to publications in Nutritional Neuroscience and Behavioural Brain Research.

Changes in the gut bacteria protect against stroke

The human body contains ten times more bacterial cells than human cells, most of which are found in the gut. These bacteria contain an enormous number of genes in addition to our host genome, and are collectively known as the gut metagenome.

How does the metagenome affect our health? This question is currently being addressed by researchers in the rapidly expanding field of metagenomic research. Several diseases have been linked to variations in the metagenome. Researchers at Chalmers University of Technology and Gothenburg University now also show that changes in the gut metagenome can be linked to atherosclerosis and stroke.

The researchers compared a group of stroke patients with a group of healthy subjects and found major differences in their gut microbiota. In particular, they showed that genes required for the production of carotenoids were more frequently found in gut microbiota from healthy subjects. The healthy subjects also had significantly higher levels of a certain carotenoid in the blood than the stroke survivors.

Carotenoids are a type of antioxidant, and it has been claimed for many years that they protect against angina and stroke. Thus, the increased incidence of carotenoid-producing bacteria in the gut of healthy subjects may offer clues to explain how the gut metagenome affects disease states.

Carotenoids are marketed today as a dietary supplement. The market for them is huge, but clinical studies of their efficacy in protecting against angina and stroke have produced varying results. Jens Nielsen, Professor of Systems Biology at Chalmers, says that it may be preferable to take probiotics instead – for example dietary supplements containing types of bacteria that produce carotenoids.

“Our results indicate that long-term exposure to carotenoids, through production by the bacteria in the digestive system, has important health benefits. These results should make it possible to develop new probiotics. We think that the bacterial species in the probiotics would establish themselves as a permanent culture in the gut and have a long-term effect”.

“By examining the patient’s bacterial microbiota, we should also be able to develop risk prognoses for cardiovascular disease”, says Fredrik Bäckhed, Professor of Molecular Medicine at Gothenburg University. ”It should be possible to provide completely new disease-prevention options”.