Two ways of aging
Molecular biologists and bioengineers from the University of California at San Diego have described the key mechanisms of aging. They identified two pathways that cells go through during aging, and developed a new way to genetically program these processes to increase life expectancy.
The life expectancy of a person is determined by the aging of individual cells of the body. To understand whether different cells age at the same rate and for the same reason, the researchers studied aging in yeast Saccharomyces cerevisiae.
The researchers were able to show that cells of the same genetic material in the same environment can age in different molecular and cellular ways. Using microfluidics, computer modeling and other methods, they found that about half of the cells age due to a gradual decrease in the stability of the nucleolus with a high level of DNA suppression, the other half due to the accumulation of heme and heme-dependent transcription, in which mitochondrial dysfunction occurs.
How the "destinies" of cells following different "aging programs" diverge. Yang Li et al. / Science, 2020.
Cells "choose" the path of aging of nucleoli or mitochondria at an early age and follow it throughout life.
To understand how cells make this decision, Nan Hao and his group identified the molecular processes underlying each aging pathway, as well as the connections between them. They identified a molecular circuit that controls the aging of cells, similar to an electrical circuit that controls the operation of household appliances.
By developing a new model of the aging process, researchers have found that they can manipulate and optimize it. They have developed a genetically novel third way of aging, consisting in the overexpression of Sir2 deacetylase, which contributes to the suppression of ribosomal DNA. This pathway is associated with a higher average life expectancy.
This study shows that it is possible to develop a gene or chemical therapy to reprogram the aging of individual human cells to delay the aging of the whole organism and lengthen the time of a healthy life.
The authors plan to repeat the experiments on more complex cells and organisms and, eventually, on human cells to find similar aging pathways. They will also test chemical methods of reprogramming aging to assess whether combinations of therapeutic agents and medicinal "cocktails" can lead to healthy longevity.
Article Y.Li et al. A programmable fate decision landscape underlies single-cell aging in yeast published in the journal Science.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru Based on UC San Diego: Researchers Discover Two Paths of Aging and New Insights on Promoting Healthspan.