The cold activates a cellular cleansing mechanism that breaks down harmful protein aggregates responsible for various diseases associated with aging.
- A moderate drop in body temperature can have very positive effects.
- Cold actively removes protein clumps, thereby preventing protein aggregation which is pathological in some age-related diseases.
- These results could provide therapeutic targets for aging and related diseases.
In recent years, studies on different model organisms have already shown that life expectancy increases significantly when body temperature is lowered, but the precise way in which this works is still unclear in many areas. A team from the Aging Research Group at the University of Cologne discovered the mechanism responsible and published their work on April 3 in Nature Aging.
The cold actively removed harmful protein clumps
Professor Dr David Vilchez and his colleagues used a non-vertebrate model organism, the nematode Caenorhabditis elegans, and cultured human cells. Both carried the genes for two neurodegenerative diseases that typically occur in older people: amyotrophic lateral sclerosis (ALS) and Huntington’s disease. Both diseases are characterized by accumulations of harmful and damaging protein deposits, called “pathological protein aggregations”. In both model organisms, cold actively removed protein clumps, thereby preventing protein aggregation that is pathological in both ALS and Huntington’s disease.
More specifically, the scientists explored the impact of cold on the activity of proteasomes, a cellular mechanism that removes damaged proteins from cells. Research revealed that the proteasome activator PA28γ/PSME3 alleviated deficits caused by aging in both nematode and human cells. In both cases, it was possible to initiate proteasome activity by a moderate decrease in temperature.
“Taken together, these results show how, over the course of evolution, cold has retained its influence on proteasome regulation, with therapeutic implications for aging and age-associated diseases. We believe these results can be applied to other age-related neurodegenerative diseases”Professor Vilchez said in a communicated. These results could provide therapeutic targets for aging and related diseases.
A moderate drop in body temperature can have positive effects
It has long been known that while extremely low temperatures can be harmful to organisms, a moderate drop in body temperature can have very positive effects. For example, a lower body temperature prolongs the longevity of cold-blooded animals such as worms, flies or fish, whose body temperature fluctuates with the temperature of the environment.
However, the same phenomenon also applies to mammals, which maintain their body temperature within a narrow range, regardless of how cold or hot their environment is. For example, the nematode lives much longer if moved from the standard temperature of 20 degrees Celsius to a colder temperature of 15 degrees Celsius. And in mice, a slight decrease in body temperature of just 0.5 degrees significantly extends their lifespan. This supports the hypothesis that temperature reduction plays a central role in longevity in the animal kingdom and is a well-conserved evolutionary mechanism.
Even in humans, a correlation between body temperature and lifespan has been reported. The normal human body temperature is between 36.5 and 37 degrees Celsius. While an acute drop in body temperature below 35 degrees leads to hypothermia, human body temperature fluctuates slightly during the day and even reaches 36 degrees during sleep. Interestingly, a previous study reported that human body temperature has steadily decreased by 0.03 degrees Celsius per decade since the industrial revolution, suggesting a possible link to the gradual increase in human life expectancy over the past 160 last years.
