A new study analyzing macaque monkeys that survived Hurricane Maria in Puerto Rico finds that extreme weather events may accelerate aging in humans.
Macaque monkeys aged two years after hurricane, study finds
According to the study, published in the Proceedings of the National Academy of Sciences (PNAS) on the 7th, macaques that experienced hurricanes appeared to have aged an average of nearly two years compared to macaques that did not experience disasters, equivalent to seven to eight years of human lifespan. This suggests that when the frequency of extreme weather events increases due to the climate crisis, it may bring adverse biological consequences to animals that experience these events.
Category 4 Hurricane Maria struck Puerto Rico in September 2017, killing more than 3,000 people, leaving the island's 3.4 million residents without power for weeks, and causing more than $100 billion in damage.
In addition to the human toll, the hurricane also affected Puerto Rico's wildlife, such as the free-roaming macaque population on nearby Cayo Santiago Island.
Scientists analyzed the health data of a population of macaques that had lived at the local Caribbean Primate Research Center since 1938, four years before the hurricane and one year after it. They found that Hurricane Maria may have accelerated the aging of the macaques' immune systems.
4% of genes related to macaque immune cell expression were changed
Past studies have found that people who survive extremely adverse experiences have a higher risk of heart disease and other common illnesses in older adults, but researchers say it's unclear how these harmful experiences contribute to disease.
People born in the same year may have different biological ages, which determines when and how they develop such diseases.
In the new study, scientists analyzed the surviving macaques for biological markers of aging, including molecular changes and disruptions in genes involved in inflammatory responses and in helping proteins fold into their proper functional structures.
Researchers found that approximately 4% of the genes involved in immune cell expression in the macaques were altered after the hurricane. The study also indicated that genes with increased expression after the hurricane were associated with inflammatory responses, while genes with decreased expression were related to the body's natural protein production, structural modification processes, and adaptive immune responses.
"On average, macaques that experienced the hurricane had an immune gene profile that was two years longer, or about seven to eight years of human lifespan," said lead author Marina Watowich of the University of Washington.
Exposure to extreme natural disasters will accelerate biological aging
A key mechanism involved in gene regulation in immune system cells could explain how events associated with extreme weather and other natural disasters can trigger diseases related to biological age, researchers say.
“In individuals exposed to extreme natural disasters, we found changes in immune cell gene expression that mimicked the natural aging process in many respects,” said Noah Snyder-Mackler, another author of the study. “We also observed evidence of accelerated biological aging in animal samples from Hurricane Maria.”
The scientists also found that some macaques' biological age increased more than others, suggesting that other environmental factors may influence their responses to adversity. For example, macaques that received more social support after a storm were better able to overcome various adverse effects.
However, the researchers also emphasized that a limitation of this study was that it was not possible to measure the aging rate of the same group of macaques before and after the hurricane.
Source: Environmental Information Center (https://e-info.org.tw/node/233347)