The study found that rising ocean temperatures could threaten this unique species of shark.
Sharks are known as one of the most powerful and fearsome creatures in our oceans. But now it turns out that a certain species can teach us how to improve our heart health.
New experimental research presented at the ongoing Society for Experimental Biology conference in Prague suggests that muscle metabolic activity may be an important factor in the incredible longevity of the world’s oldest living vertebrate species, the Greenland halibut.
Scientists believe that these results could be good news for the conservation of this sensitive species and for human health.
What sharks can teach us about living longer
Also known as Somniosus microcephalus, the Greenland shark is the longest-lived vertebrate, with a life expectancy of 270 to 500 years or more.
“We want to understand what adaptations they have that allow them to live so long,” says Ewan Camplisson, a PhD student at the University of Manchester who worked on the study.
Previously, this longevity was thought to be due to the shark’s cold environment and limited movements. It has now been discovered that the factors behind this species’ extreme longevity appear to be much more complex.
So Camplisson and his team decided to study alternative theories.
“Most species show age-related changes in metabolism,” explains Camplisson. “We wanted to determine whether Greenland sharks also show this traditional sign of aging, or whether their metabolism remains unchanged over time. »
What tests did researchers conduct on Greenland sharks?
To measure the metabolism of sharks, Camplisson’s research team performed enzymatic tests on samples of the animals’ preserved muscle tissue.
Using a spectrophotometer—an instrument that measures the intensity of light absorbed after passing through a sample solution—they measured the metabolic activity of enzymes in sharks of different ages and at different environmental temperatures.
Following this study, Camplisson and his team found no significant change in the metabolic activity of the muscles depending on the age of the sharks.
This indicates that their metabolism does not decrease over time and may even play a key role in their longevity.
“This is very different from most animals, which tend to show some change in metabolic enzyme activity as they age,” says Camplisson. “The results support our hypothesis that Greenland sharks do not show the same traditional signs of aging as other animals. »
How do these results improve our understanding of Greenland shark health and ours?
The results of the shark study also showed that the metabolic enzymes of the Greenland species are significantly more active at high temperatures.
“This suggests that shark red muscle metabolism is not particularly adapted to polar environments, where we would otherwise expect to see less temperature-related variation in activity,” Camplisson said.
However, climate change brings with it a particularly worrisome potential trend that could weaken the adaptive capacity of long-lived species and therefore put them at risk of extinction.
“Female Greenland sharks do not become sexually mature until they are 150 years old, and with such a long generation time, the species will be less likely to adapt to anthropogenic changes in their environment,” explains Camplisson.
Camplisson has not yet completed his research on the Greenland shark.
In the future, he plans to test more enzymes and tissue types to gain a deeper understanding of shark metabolic activity, taking into account the effects of climate change.
“My main goal is to protect species, and the best way to do that is to understand them better,” he says.
What do his findings mean for humans and heart disease in particular?
“These are problems that become more frequent and more serious with age,” he says. “By studying the Greenland shark and its heart, we can better understand our own cardiovascular health. »