At a glance:
- Living in a low-oxygen environment extended life spans, preserved neurologic function in mice.
- Findings add to a growing body of research showing oxygen restriction may ward off neurologic decline and extend life span in animal models.
- Mechanisms behind the protective effects of oxygen deprivation remain to be elucidated.
A strain of mice born with abnormally short life spans defied expectations and lived 50 percent longer than expected when put in an environment with low oxygen roughly equivalent to a Mount Everest base camp, Harvard Medical School scientists report in a new study.
The findings, published May 23 in PLOS Biology, add to a growing list of approaches shown to lengthen life in animal models and provide the first demonstration that oxygen restriction could extend life span in a mouse model of aging.
Epidemiological observations have offered tantalizing clues to a curious phenomenon — people who reside at high altitudes tend to live longer and appear less prone to developing certain diseases.
In the new study, researchers sought to determine whether they could replicate this finding in animals.
“Epidemiological studies have hinted that populations that live at higher altitudes tend to live longer and stay healthier as they age. We wanted to test whether, in a more controlled setting, restricting oxygen appears to do the same in our mouse model of aging”,” said study senior author Vamsi Mootha, professor of systems biology in the Blavatnik Institute at Harvard Medical School.
Since time immemorial, humans have sought to cheat — or at least delay — death by extending their natural life spans, said study first author Robert Rogers, a postdoctoral researcher in the Mootha Lab.
This quest may be within closer reach with a mounting body of research over the past few decades that has identified a number of ways that significantly lengthen the lives of cells in petri dishes and common lab animals such as roundworms, fruit flies, and mice.
These strategies include caloric restriction and use of the diabetes medication metformin, the immunosuppressive drug rapamycin, and aspirin — all of them in various stages of testing in animal models and humans.
Some studies have suggested that oxygen restriction — limiting the concentration of oxygen in the ambient air at a level significantly below that at sea level, about 21 percent — can also extend life span in a variety of models, including fruit flies, worms, yeast, and mammalian cells in lab dishes. Thus far, however, oxygen restriction has remained unexplored in mammalian aging.