The secret of cold-blooded animals' 'young and old forever'

Not only turtles, some cold-blooded animals such as salamanders, frogs. also have a very slow aging rate, which helps them to prolong their lifespan compared to other creatures. This discovery has brought scientists closer to the secret of the mechanism of aging.

Cold-blooded animals live longer?

Lizards can regrow limbs and tails if cut off.

When it comes to longevity, scientists have long paid special attention to turtles and turtles, animals that can live a long time. For example, the oldest known animal today is a 190-year-old giant Seychelles tortoise named Jonathan.

Recently, biologist Beth Reinke, working at Northeastern Illinois University, Chicago, USA, and colleagues conducted large-scale studies of aging in wild populations.

The study is based on the hypothesis that the reason turtles live so long is because they are cold-blooded animals that do not have to expend energy to maintain body temperature. From there, they can channel their energy into fighting the aging process.

To confirm this hypothesis, Beth and her colleagues compared the aging rates of cold-blooded and warm-blooded animals. 100 researchers from around the world compared the aging rates of 77 species of reptiles and amphibians in the wild. They found that the aging rate of cold-blooded animals was not much different from that of warm-blooded animals.

However, among cold-blooded animals, the aging rate is quite large compared to warm-blooded animals. Specifically, some cold-blooded species age faster than similarly sized warm-blooded species, while others age more slowly. In particular, turtles, frogs, crocodiles and salamanders and lizards age very slowly.

Life expectancy in reptiles and amphibians varies from 1 to 137 years - a much broader range than the 4 to 84 years seen in primates. However, species with insignificant senescence occur in reptiles and amphibians, and turtles are among the slowest.

In addition to turtles, lizards are particularly promising for future aging research. Many lizards can live 10 years or more. With its small size, lizards can easily hide from enemies or camouflage.

Furthermore, they are famous for their ability to regrow severed limbs and tails, leading many scientists to believe that there is a link between the lizard's ability to 'regenerate' and long life.

Because cold-blooded factor is not the answer to slow aging, the researchers tested several additional studies to understand why some cold-blooded species age quickly while others do the opposite. again. After looking at local temperatures, they found that hot climates accelerate aging in reptiles but decrease them in amphibians.

Jonathan the tortoise is 190 years old this year.

Energy conversion process

One of the most interesting findings in Beth Reinke's research is that the slowest aging cold-blooded animals are also the creatures with the strongest defenses to help them escape the clutches of predators. In particular, physical protection such as shells and apricots are associated with low rates of aging.

The shell helps to prevent the turtle from being eaten, which means that the turtle's chance of dying from external factors is lower than that of such unprotected animals. The low mortality rate at any age means turtles can survive long enough to activate cellular defenses against aging. In other words, being protected allows animals to live long enough to evolve into an anti-aging form.

Agreeing with this point of view, research by biologist Rita da Silva, University of Southern Denmark, on 23 species of turtles living in captivity shows that 75% have zero or no aging rate. significantly.

This means turtles can age very slowly or not at all in captivity. Some species have a negligible aging rate, including Greek turtles, black swamp turtles, Aldabra giant tortoises. with an average lifespan of 60 years or more.

In captivity, reptiles do not have to expend energy in search of food or shelter. As a result, some species like turtles have converted this energy source into the ability to destroy damaged cells and fight the DNA damage that builds up over time during cell division, helping to protect the body. even as they enter old age.

The results of both studies were published in scientific journals and were well received by experts. Ecologist Rob Salguero-Gómez, of the University of Oxford, UK, said the new finding is not surprising but challenges previously understood understanding of aging.

In fact, it is uncommon for a process of decline in bodily function that increases the risk of death after an organism reaches adulthood. This adds to the scientific community's understanding of aging in the evolutionary tree.

Studies are getting closer to the anti-aging abilities of turtles and tortoiseshells, but it's still too early to tell if these findings are related to aging in humans.

Scientist Rita da Silva notes that particular care must be taken when making these comparisons because scientists have not been able to find a clear link between aging in turtles and humans. But it can be said that humanity has gone a step further in understanding the mechanism of aging.