The metabolism of Greenland sharks may help explain their longevity

• Greenland sharks can live up to 400 years, making them the longest-lived fish.
• Scientists are studying the secrets of these sharks’ longevity.
• Understanding the longevity of Greenland sharks may improve human health and aging research.

Abigail Adams, the wife of the second US president, was born in 1744. It is quite possible that the Greenland sharks that were swimming in the North Atlantic Ocean at that time are still alive today.

There is no doubt that these large, predatory sharks can live for hundreds of years. In 2016, researchers found that they can live at least 272 years, but they can live up to 400.

However, why these sharks live so long is a mystery. Some theories include the shark’s slow growth rate and low metabolic rate, but research continues.

Scientists hope that unlocking the secrets of these fish’s lifespan will help people live longer and healthier lives. We may not live to be 400 years old, but extending the average human lifespan by another ten years would be a great achievement.

One of the scientists on the hunt is Evan Camplisson. He is studying the metabolism of sharks and their aging process.

“Better understanding the anatomy and adaptations of a long-lived species like the Greenland shark allows us to improve human health,” Camplisson, a PhD student at the University of Manchester, told Business Insider.

Slow metabolism throughout life

Greenland sharks, found mostly in the Arctic and North Atlantic oceans, are slow swimmers, measuring 8 to 23 feet in length and weighing up to 1.5 tons, according to National Geographic.

Predators feed on salmon, eels, seals, and even polar bears. However, they can probably go a long time between meals. According to a 2022 study, a 493-pound fish can do well on between 2 and 6 ounces of food per day.

New research by Camplisson, presented earlier this month at the Society for Experimental Biology’s annual conference, suggests that sharks’ metabolic rates may not slow as they age, which could help explain why sharks live so long.

This is not the case for most animals, including humans. For example, a person’s metabolism slows down in later years, which contributes to unhealthy weight gain.

Camplisson examined the activity of five metabolic enzymes preserved in Greenland shark muscle tissue. “In most species, animal age predicts changes in the activity of these enzymes,” he said.

“Some of them will show a reduction over time because they may start to fail or deteriorate, while others will compensate and increase their activity to make sure the animal is still producing enough energy,” he added.

Looking at Greenland sharks estimated to be 60-200 years old, they found no change in enzyme activity. Of course, a Greenland shark can only be middle-aged at 200 years old, so it won’t be until they reach the third or fourth century.

Camplisson plans to look at more enzymes to see if and how enzymes change as sharks age.

Aging is complicated

More work needs to be done before such research can be applied to humans.

“Aging is an incredibly complex system, and we still don’t have a clear answer to exactly how it works,” Camplisson said.

For example, changes in metabolism are only one part of aging in humans. Genetic errors, protein instability, and a number of other processes are known as “signs of aging.” According to Camplisson, sharks have more to teach us in these areas.

“We want to take a closer look at some of these traits to see if the Greenland shark has signs of traditional aging,” he said.

While Greenland sharks’ remarkable aging process allows them to survive for centuries, this can be a double-edged sword as their environment changes rapidly.

Camplisson said the species, considered “endangered” by the World Conservation Union, may be too slow to adapt to climate change, marine pollution and other stressors.