Suppressing the activity of the mTOR gene prolongs life by 20%
By suppressing the activity of the mTOR gene, American scientists from the National Institute of Heart, Lung and Blood Diseases, working under the guidance of Dr. Toren Finkel, extended the life of mice by about 20%. This corresponds to an increase in the average life expectancy of a person by 16 years – from 79 to 95 years. The target gene chosen by the authors is involved in the metabolism and maintenance of the body's energy balance. There is also evidence of the relationship between its activity and the life-prolonging effect of a low-calorie diet.
To conduct the study, the scientists created genetically modified mice, in whose body only about 25% of the normal amount of the protein product of the mammalian rapamycin target gene mTOR was produced. This roughly corresponds to the minimum level of protein required to maintain the vital activity of the body. Apart from the slightly smaller body size, the mice of this line were no different from normal animals.
The average life expectancy of experimental animals was 28 months for males and 31.5 months for females. In the control group, these indicators were equal to 22.9 and 26.5 months, respectively. Genetic modification also increased the maximum lifespan of mice, which was more pronounced in males (see graph).
Drawings from an article in Cell ReportsA detailed study of the state of the organism of genetically modified mice showed that, despite the significantly better health of aging animals as a whole, a decrease in the activity of the mTOR gene had only a selective positive effect on the functioning of individual organs.
For example, aging experimental animals consistently demonstrated a better state of muscle tissue and higher results when performing tasks to find a way out of the maze and maintain balance, which indicates better memory retention and the ability to coordinate movements. At the same time, their bone tissue was destroyed faster than the bone tissue of normal mice, and an age-related increase in the frequency of infectious diseases indicated a decrease in immune function.
The authors believe that the results obtained can help in the development of treatment methods for age-related diseases affecting individual organs, for example, Alzheimer's disease. However, in order to clarify the molecular mechanisms linking the aging processes of various tissues and the role of the mTOR protein in these processes, it is necessary to conduct further studies on mice and human cells.
Article by J. Julie Wu et al. Increased Mammalian Lifespan and a Segmental and Tissue-Specific Slowing of Aging after Genetic Reduction of mTOR Expression is published in the journal Cell Reports.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on materials from NIH / National Heart, Lung and Blood Institute:
Single gene change increases mouse lifespan by 20 percent.
02.09.2013