If you read this and you are not a smoker, then the main risk factor for death is probably your age for you. This is because we almost completely eliminated early-stage mortality, thanks to advances in science and engineering. But despite this progress, we have not yet found out how to remove the damaging effects of aging itself.
New research on mice, published in Nature reveals that stem cells (type of cells that can develop into many other types) in a certain brain area regulate aging. Researchers have been able to slow down and accelerate the aging process by transplanting or eradicating stem cells from that area.
Aging is a huge challenge for society. It is estimated that by 2050, for the first time ever, the number of older people (over 65) and children (under 15) on Earth will be equalized. This change is reflected in the problems of health systems and social welfare systems. It is becoming increasingly important to understand how to maintain good health while we are alive.
The number of mechanisms that keep healthy organisms is relatively small and they are preserved among species, meaning that we can learn a lot about them by studying animals like mice. Among the most important are senese cells – dysfunctional cells that are formed while we are aging and cause tissue damage. It is believed that these mechanisms are linked at the cellular and tissue levels. Like collapsing domination, collapse in any place can trigger catastrophic collapse.
Researchers behind this new work have studied the hypothalamus of mice, for which we already know to control aging. This structure, which has a hazel shape, is located in the center of the brain and connects the nervous and endocrine (hormonal) system. The hypothalamus helps regulate many basic needs and behaviors such as hunger, sleep, fear and aggression. In a human brain, the beginning of a behavior is usually very complex, but if you run away from something in a panic or get caught in wild anger, then your hypothalamus is on the wheel.
The team studied a specialized stem cell group in the hypothalamus and tracked what happens to them while the mice are old. Mice usually live for about two years, but they have discovered that these cells are beginning to disappear when mice have had about 11 months. By 22 months the cells were completely gone. The rate at which stem cells disappear is closely related to changes that cause aging, such as decline in learning abilities, memory, sociability, muscular endurance and athletic performance.
However, correlation does not mean that there is a cause-and-effect relationship. In order to find out if the stem cell count decreases this age change, stem cells have been deleted by a specifically designed virus that kills them only in the presence of a particular drug. In mice over the past 15 months, this combination has destroyed 70 percent of stem cells in the hypothalamus. Signs of aging with them were shown to be urinary and mice died about 200 days earlier as a result. This is a significant figure because mice average live about 730 days
Researchers have built hypothalamic stem cells of newborn mice in medieval mice. In this case, the animals became more socially, cognitively capable and lived for 200 days longer than their normal life span.
These experiments offer information on how stem cells disappear from the hypothalamus. Infection was successful only when the stem cells were genetically modified to be resistant to inflammation. It appears that while the animal's old, chronic, low level of inflammation in the hypothalamus increases.
Inflammation kills hypothalamic stem cells because they are the most vulnerable. This hampers the function of a hypothalamus with domino effect in the whole organism.
Elixir of Youth
The ultimate goal of aging research is to identify pharmaceutical targets or interventions in a lifestyle that will improve human health in later life. Although this research was carried out on mice, if they were able to show that the same mechanisms were in the work of humans, one day they could use a similar technique to improve the health of later life. But this is far in the future.
Other interventions, such as removing sneezing cells, also have a positive effect on health, extending the life of mice for up to 180 days. A logical next step is to see if these interventions can be "dropped off."
This study points to potential pathways for stem cell repair: preventing their loss by controlling the inflammatory process. This could be achieved by the development of drugs that kill sneezing cells or the use of anti-inflammatory compounds.
The disadvantage of this research is that only male mice have been used. It is well known that the structure of the hypothalamus is significantly different between the sexes. Life-prolonging drugs and mutations usually have significantly different degrees of effectiveness in males and females.
Will people ever live significantly above the current longest life of 125 years is hard to say. But the biggest obstacle to healthier later life is, it seems, no longer a rate of development but the speed with which we can turn our growing knowledge of aging biology into medicines and lifestyle advices.