So that the memory becomes like a young one
Researchers at the University of Edinburgh managed to restore the "youth of mind" to aging mice with the help of an experimental drug that suppresses the production of stress hormones glucocorticoids.
Article by Karen Sooy et al. Partial Deficiency or Short-Term Inhibition of 11β-Hydroxysteroid Dehydrogenase Type 1 Improves Cognitive Function in Aging Mice is published in the latest issue of The Journal of Neuroscience. A summary of the results of the study is published in Technology Review (Experimental Drug Preserves Memory in Rodents).
A short-term increase in the level of glucocorticoids synthesized by the adrenal glands contributes to the memorization of events in stressful situations, however, chronic exposure to high concentrations of these hormones exacerbates age-related memory loss in both animals and humans. The mechanisms of this phenomenon are not completely clear, but scientists suggest that exposure to glucocorticoids contributes to damage to certain areas of the brain.
The authors turned their attention to the enzyme 11-beta-hydroxysteroid dehydrogenase type I, which provides the formation of the active form of the most important glucocorticoid hormone in brain cells and a number of other tissues. Suppression of the activity of this enzyme allows you to selectively neutralize the destructive effect of hormones, without disturbing the development of stress reactions important for the body as a whole.
Blocking one or both copies of the gene encoding 11-beta-hydroxysteroid dehydrogenase protected mice from senile memory loss. Moreover, a 10-day course of a drug developed by scientists that penetrates the blood-brain barrier and inhibits the activity of an enzyme in brain cells rejuvenated the brains of two-year-old mice (the maximum age of ordinary laboratory mice) to such an extent that when performing a spatial memory test, they were not inferior to young healthy animals.
According to experts, 20-30% of people aged 75 years and older are characterized by elevated levels of glucocorticoids. Most of all, the so-called declarative memory suffers, that is, the ability to memorize new facts. Senile memory loss is a risk factor for developing Alzheimer's disease, as well as other forms of dementia.
Currently, researchers are working on creating a drug that can restore memory to the elderly, while protecting them from Alzheimer's disease. They also note that the new drug may have positive side effects: earlier animal experiments showed that blocking 11-beta-hydroxysteroid dehydrogenase in mice normalizes tissue sensitivity to insulin and blood glucose levels. Moreover, several pharmaceutical companies are already working on the creation of similar compounds intended for the treatment of type 2 diabetes.
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of CNews R&D
20.10.2010