Longevity and disease resistance in humans may soon be transformed by studying and emulating the genetic strategies encoded in nature’s most resilient and long-lived species. As explored in the book Live Longer: What You Can Do, What Medicine Can Do, which I coauthored, current research is unlocking how the Arctic bowhead whale, African elephant and microscopic tardigrade use DNA repair systems and molecular shields to defy the expected limits of lifespan and resist cancer. Now, research is working to adapt these mechanisms for use in mammalian cells. It is also exploring new therapies for aging, cancer and post-surgical recovery.
The Evolutionary Outliers
The evolutionary outliers set the stage for this exploration. Take the bowhead whale, a giant of the Arctic, for example. It claims the crown for mammalian longevity. These whales survive up to 200 years in frigid waters and maintain genome stability despite having billions of cells and a lifespan spanning centuries. The recently profiled Greenland shark also stands out among these outliers, with a lifespan often estimated between 300 and an astonishing 500 years, making it the longest-lived vertebrate known to science. Their stable metabolism, slow growth and resistance to environmental assaults provide a compelling model to decode the biological roots of longevity.
Then there are elephants, with bodies containing vastly more cells than humans. They defy cancer statistics. More specifically, they rarely develop tumors. This phenomenon has perplexed researchers for decades, leading to what is called Peto’s Paradox. It describes how large, long-lived animals such as elephants and whales do not have higher cancer rates than smaller animals, despite having more cells and a greater statistical risk.
The idea is that these species have evolved effective cancer suppression mechanisms, including enhanced DNA repair, a form of programmed cell death that removes damaged cells and cell cycle regulation. The finding challenges previous assumptions about cancer risk and drives research into similar mechanisms in other organisms.
For example, the bacterium Deinococcus radiodurans is often referred to as the most radiation-resistant organism known. The bacterium thrives in environments with intense radiation that would otherwise be lethal to most life forms. This is similar to what is seen in tardigrades.
What Earth’s longest-lived animals can teach us about aging better
A humble mollusk can live to 507. The oldest Greenland Sharks navigate deep, dark Arctic waters for longer than America has existed. And the wrinkly, cancer-resistant naked mole rat can live well into its 30s, a veritable rodent Methuselah.
Human centenarians excite a deep fascination. What are their secrets? Do they eat breakfast? Skip lunch? Exercise every day? What genes helped keep them strong and disease-free, years longer than most people? But across the animal kingdom, evolution has given rise to much vaster age gaps — and a growing scientific quest to understand what a menagerie of creatures with the extraordinary ability to defy the ravages of time can teach us about to make human aging better.
For more than two decades, longevity researchers have been testing interventions to extend the lives of lab mice, a step toward antiaging drugs for humans.
“We can make mice live 30 percent longer. It doesn’t really work for anything greater than that — but if you look at the wild kingdom, you can find 100-fold differences within mammals that are similar to us,” said Vera Gorbunova, a biologist at the University of Rochester and a leader in the field.
Scientists like Gorbunova scour the natural world for exceptionally long-lived outliers, from beavers to bats to sharks, to learn more about how they stay cancer-free, resist infections or retain their eyesight for centuries. They also look for consistency — specific genes, proteins or enzymes that exist in a variety of animals and might be a basic component of long life.
“Nature has had several billion years to experiment with ways of making animals resist aging better,” said Steven Austad, an aging researcher at the University of Alabama at Birmingham and author of the book “Methuselah’s Zoo.” “If we look at animals that do things better than we do, maybe we could get some better clues about how to keep ourselves healthy longer.”
Read the full story: What Earth’s longest-lived animals can teach us about aging better (WaPo)