Prevention of senile dementia: keep your belly hungry!
Malnutrition may protect the brain from Alzheimer's disease
Hormones responsible for the feeling of hunger and satiety play a leading role in the mechanism of this protection. The results of the study are published in the journal PLoS ONE (Hunger in the Absence of Caloric Restriction Improves Cognition and Attenuates Alzheimer's Disease Pathology in a Mouse Model).
Caloric restriction of food consumed is a diet in which a person consumes slightly fewer calories than is recommended on average, but not so little as to starve. Many studies have proven the benefits of such a technique not only for maintaining a normal weight, but also for health. It has been proven that limiting daily calorie intake prolongs life. The results of animal experiments also suggest that light fasting can protect the brain from the development of neurodegenerative diseases, but the mechanism of this protection has not yet been studied.
Inga Kadish from the Department of Cell Biology at the University of Alabama School of Medicine (School of Medicine at the University of Alabama) and her colleagues suggested that the feeling of hunger creates a state of moderate stress in the body. This, in turn, activates signaling metabolic pathways that prevent the deposition of beta-amyloid plaques that destroy nerve cells in Alzheimer's disease. To test this theory, scientists analyzed the effect of the hormone ghrelin, which is synthesized by the cells of the gastric mucosa and causes hunger. Scientists gave mice a precisely dosed synthetic form of the hormone in tablets so that the mice constantly remained a little hungry. Another group of mice kept on a calorie restriction regime (20 percent less than normal), and the third ate normally. At the same time, all mice were endowed with three genetic mutations that cause the development of Alzheimer's disease in humans.
For a long time, researchers have been evaluating the ability of mice to memorize information and the presence of beta-amyloid deposits in their brains. The results showed that the first two groups of mice passed the maze much better and faster than mice who ate normally. The maze is the best test for evaluating the memory of mice and the speed of memorizing new information. Analysis of the formation of beta-amyloid deposits in the brain of mice showed that in the first two groups of mice, the rate of their formation was much lower than in mice on a normal diet. In general, both ghrelin intake and calorie restriction reduce the formation of beta-amyloid plaques by 48 percent, and the overall risk of developing Alzheimer's disease by 67 percent. Thus, the researchers proved once again that moderate malnutrition can protect against the development of this disease. And for those who cannot limit themselves to food for a long time, scientists hope to offer fundamentally new medicines — ghrelin agonists in the near future.
Portal "Eternal youth" http://vechnayamolodost.ru08.04.2013