Can the Smell of Rotten Eggs Make You Live Longer?
Hydrogen sulfide makes rotten eggs smell horrible, but the chemical may also be a fountain of youth. Researchers have found that when nematode worms were exposed to an atmosphere containing a small amount of hydrogen sulfide, the worms' lifespan increased significantly.
Worms exposed to a small concentration (50 parts per million) of hydrogen sulfide lived up to eight times longer than their counterparts breathing normal air. The team, from the Fred Hutchinson Cancer Research Center, achieved similar results in 15 different experiments.
While the effects varied, the average lifespan increase was significant. About 77% of worms demonstrated a longevity increase of 70%. In a nematode's life, that's only 9.6 days, but in a human's, it could be more than 50 years.
Of course, the results don't necessarily mean that exposing humans to hydrogen sulfide will have the same effects. Still, nematode worms have many biological similarities with humans, including a central nervous system and the ability to reproduce. But since they only live for two to three weeks, the worms are ideally suited for studying lifespan.
"Further research into the genetic mechanisms that influence H2S-induced changes in nematodes may reveal similar mechanisms in higher organisms, including humans, with potentially wide-ranging implications in both basic research and clinical practice," Mark Roth, one of the researchers, said. For example, understanding how hydrogen sulfide affects physiology in animals may lead to the development of drugs that could delay the onset of age-related diseases in humans such as cancer, Alzheimer's and heart disease.
In 2005, Roth was the first to show that exposing mice to small amounts of hydrogen sulfide causes the animals to shut down metabolically, entering a state of hibernation. In humans, such a tool could be useful for "buying time" for severely ill patients who might face injury or death from insufficient blood and oxygen supply to organs and tissues.
Roth has a hypothesis for the cause of hibernation. Hydrogen sulfide, which is found in small amounts in the body, is molecularly similar to oxygen and binds at some of the same proteins. Hydrogen sulfide likely competes with oxygen and interferes with the body's ability to use oxygen for energy production. Without oxygen, the body shuts down.
But how hydrogen sulfide prolongs life is not yet understood. Roth and his colleague Dana Miller ruled out each of the three genetic pathways that are known to influence lifespan in the nematode. However, they're investigating another gene that might play a role.
However far-fetched they seem, these results may help people avoid or overcome a wide variety of illnesses.