Moscow, 28 Apr, Vladislav Dragonhopytov. x Slottering proteins — process that leads to premature cell death. This explains the evidence that cold has a beneficial effect on lifespan.
Protein aging
It is known that the basis of many diseases associated with aging is the process of protein aggregation, when abnormally folded and clumped proteins, known as amyloid fibrils, accumulate in tissues.
This happens for various reasons: due to mutations in the DNA sequence, when normal protein synthesis is disrupted, during environmental stresses such as extreme temperatures, when exposed to oxidants (reactive oxygen species), and as a result of aging.
Cells have control mechanisms that monitor and remove abnormally twisted proteins. However, with age, the protection weakens and protein aggregates begin to accumulate in tissues, blood vessels and joints. This is one of the main causes of cardiovascular diseases, sclerosis, Alzheimer's and Parkinson's diseases.
Protein metabolism disorders in the early stages manifest themselves as a complex of symptoms of amyloidosis, such as fatigue, weakness, swelling of the arms and legs, shortness of breath, palpitations, autonomic and erectile dysfunction, indigestion, and internal inflammation. As we age, the problems increase.
Cold Rejuvenation
The results of a study that biologists from the University of Cologne conducted on a model organism, the soil worm Caenorhabditis elegans, showed that as the temperature drops, pathological protein aggregation slows down. The cold activates the cellular cleansing mechanism, which breaks down harmful protein accumulations, and the life span of the body is increased. If at standard 20 degrees Celsius C. elegans usually lives 20 days, then at 15 degrees it is almost a third longer — up to 28-29 days.
Scientists have found that at low temperatures the cell produces more activator protein PSME3, which regulates the work of proteasomes — molecular complexes that remove damaged proteins. As a result of the proteolysis reaction, peptide bonds are destroyed, the cell is cleared of harmful proteins and its life is extended.
The authors tested their findings on cultured human cells carrying risk genes for two neurodegenerative diseases that affect the elderly, amyotrophic lateral sclerosis (ALS) and Huntington's disease. The experiment demonstrated that when the temperature drops to 36 degrees, the human analogue of the PSME3 protein is activated in the cells.
«We believe that the results can be extended to other age-related neurodegenerative diseases, as well as to other animal species,» study leader Professor David Wilches was quoted in a university press release.
If extreme cooling is dangerous for organisms, then moderate cooling can have a positive effect. It has been proven to prolong the life of cold-blooded animals such as worms, flies or fish, whose body temperature is affected by environmental conditions. It turned out that the same effect applies to mammals, whose temperature fluctuates in a very narrow range. In mice, for example, lifespan is increased even with a small decrease of 0.5 degrees.
«Together, these data show that over the course of evolution, cold has retained its influence on the regulation of the proteasome — with therapeutic implications for aging and related diseases,» says Vilches.
Normal human body temperature is between 36.5 and 37 degrees. A fall below 35 causes a malfunction in physiological processes and can lead to death. But a shift of half a degree is quite acceptable. During the day, fluctuations reach one degree, and 36 degrees is considered the normal temperature of a sleeping person. It was to this value that scientists cooled human cells during the study.
“At high temperatures, metabolic processes throughout the body are much more intense and cells use up their resources faster,” explains Galina Khusainova, an expert in the field of rejuvenation and longevity, founder of the online project “Academy of Free Age”, “A decrease in body temperature slows down metabolic processes, which is natural should lead to an increase in life expectancy. The same effect is manifested with moderate fasting — a proven factor in longevity. «
The key was the discovery that proteasome activity can be increased without additional cooling, only through genetic engineering — by additional expression of the PSME3 protein . With this variant, proteasomes are able to remove pathological proteins from the body, regardless of body temperature. And this means that in the future it will be possible to create a drug to combat age-related diseases.
We are getting colder and healthier
According to medical observations, over the period from 1862, when regular measurements began, to the present day, the normal human body temperature has decreased from 36.6 to 36.1 degrees. For the past 160 years, it has been decreasing by about 0.03 degrees every decade.
There is no clear explanation for this yet. It is believed that the availability of food, more comfortable living conditions, the development of hygiene and medicine have led to a weakening of chronic inflammatory processes — therefore, temperatures have decreased. Some scientists attribute the «cooling» of modern people to a general slowdown in metabolism or to other causes, such as the active use of antibacterial drugs that suppress the activity of intestinal microbes.
According to experts, regardless of the biological mechanism, a slight decrease in body temperature has a beneficial effect on the body. After a short exposure to cold, the immune system is activated, lymph flow and capillary circulation are increased, the potential for protecting nerve cells is improved, metabolism is accelerated, the amount of pro-inflammatory components is reduced, and cellular repair processes are launched.
Hypothermia, cryotherapy, various forms of hardening are gaining more and more popularity. Cryotechnologies are widely used in cosmetology to improve skin condition, reduce wrinkles and reduce inflammation. However, they are not yet used for radical rejuvenation.
«No one can say that cold is guaranteed to prolong life,» Khusainova notes. «Because of the long lifespan, humans are an inconvenient model for experiments. So we can only rely on the findings obtained from model animals.»
“The benefits of hardening for a person have not been scientifically confirmed,” adds Ekaterina Kashukh, an expert at the Hemotest laboratory, candidate of medical sciences. “The main thing is to remember that you need to harden gradually and regularly so as not to harm the body. If you have chronic diseases, you should first consult with a doctor. Hypertensive patients and patients with cardiovascular diseases should be especially careful — such procedures can be dangerous for them. data-url=»https://ria.ru/20230405/serdtse-1862930203.html» data-title='Ball or «pear». People with what form of heart live less'>
Life expectancy is influenced by many factors: heredity, access to medical care, nutrition, lifestyle. And many of them are likely more important than ambient temperature. In addition, physical education, a positive attitude and an active life position play an important role.