The liver is aging faster than the brain – BBC

Liver cells are aging faster than the cells of the brain, scientists have found. Department of Science “Gazety.Ru” figured out why this happens, and tells how the discovery could help researchers in the fight against aging.

About that the real reflection of the physical condition of the human body is not listed in the passport of the year of birth, and biological age, scientists have known for a long time. So, recently, researchers have found that people age at very different rates: for example, the biological age of a 38-year-old man could range from 28 years to 61 years. This means that some people, the body grows old for three years for 12 months, and the other – just for one year for 16.5 months. Responding to a question about why this is happening, the study authors stated that the primary role in the formation of such differences do not play the internal factors (genetics only 20% responsible for aging rate), and external, such as the quality of food and living conditions, the intensity of training exercise, regular medical examinations.

However, the authors of an article published in the evening on September 17 in the journal Cell Systems , say: the aging process largely depends on the processes that occur over time in any particular type of cell in our body. The research team led by Martin Beck, of the European Molecular Biology Laboratory found that

different bodies age at different rates, and it happens because of the unequal rate of aging of individual cells.

The scientists analyzed the condition of the cells of the liver and brain of laboratory mice at the age of six months (equivalent to 18 “human” years) and 24 months. In contrast to previous research, the authors have focused not on the study of gene expression (ie, an understanding of which genes are “turned on” and “off” with age), and on what types of proteins produced by cells of these organs. The researchers were able to detect differences in the state of 468 proteins in young and old rodents, many of which originated in the process of protein synthesis. Furthermore, it was found that in the process of aging 130 proteins change their locations in the cell, in other words carried phosphorylation (change in protein after its creation) and splice (“notching” of certain nucleotide sequences of RNA molecules and their subsequent connection which is stored in the “mature” molecule).

Most of the scientists struck by the fact that age-related changes in the proteins were very specific: the vast majority of them were characterized by only one agency. The authors attribute this to the fact that the cells of different organs have dissimilar properties so,

liver cells during the life of the organism are updated frequently, so do not have the resistance to age-related changes. At the same time most of the neurons in the brain “lives” in it from his birth until his death the body, which means that they must have “innate” ability to withstand time. It turns out that the liver is aging much faster than the brain.

In addition, the liver cells and brain perform completely different functions if the primary goal of the first – exercise metabolism, the latter responsible for the brain neuroplasticity (the ability to change and to restore lost connections after injury or as a response to external stimuli).

«Our work shows that the aging mechanisms of different organs are different from each other and that they are controlled by the process of elaboration and updating of protein. We think that with the other organs of the situation is the same. Now we are faced with another question: can one organ affect the rate of aging of the other? “- Says one of the authors Martin Gettser.

“Gazety.Ru” talked with the head of the research team, Martin Beck and find out what role the findings made by scientists can play in the development of methods to combat aging.

– Martin, can you say – unless, of course, simplify your results – that our internal organs have different biological age?

– It is not exactly. Age they have one – it is simply a different effect on every organ. The liver has a high ability to renew itself – which means that its cells divide and updated throughout their lives – and the brain can not do it. We compared the molecule (RNA and proteins) contained in the bodies of both young and old animals. We found differences, which mean that the liver (which is, in principle, constantly updated) is much stronger than suffering from age-related changes. Furthermore, these changes differ from each other, for example in the brain affected larger molecules which are responsible for implementing the communication between cells, and in the liver of these molecules do not. The liver also suffer enzyme molecules, providing metabolism. They are present in many tissues, but in the brain are not degraded so much.

– This mechanism – the result of an evolutionary development of tissues? Can you explain why aging is so uneven?

– On the question of whether it is a product of evolution, we can clearly answer “yes”, because the lower eukaryotes (organisms whose cells contain nuclei. – “Times”) does not have a tissue. Although we know that even aging yeast cells, there are organisms that can be called a “potentially immortal.”

Specific aging bodies – a consequence of the development of specialized cells and tissues that contain specialized same molecule and perform specific tasks.

– Will the results of your work in understanding how the body as a whole is aging? Can we say that a person dies when the amount accumulated in different organs of damage reaches a certain value?

– Yes, of course, to understand how the aging system, you need to understand how to do her part. Some scientists also hope that this will help develop new – a “direct” – methods of treating certain age-related diseases. Regarding the second question … It would be better to ask your doctor. But I would say “no.” Death may occur due to a sharp deterioration of only one vital organ.

– Is it possible to be in the future in any way affect the rate of aging of various organs and thus prolong the person’s life?

– Well, you can say that this is already happening: you can eat healthy food, do not drink or smoke, thereby “helping” the liver and lungs. Although, of course, to create special drugs, to study aging of various organs have for a long time.