Of mice, men and the fountain of life

Would you smell rotten-eggs to stay young? Okay, it’s an exaggeration. Well you don’t have to literally smell rotten eggs but just get a sniff of the gas that smells like rotten eggs and you could cheat death and stay young because you’ll end up in suspended animation. At least this is what some scientists had hoped for.

I’m talking about Hydrogen Sulfide which has been reported to induce suspended animation to mice by US researchers led by study senior author Dr. Warren Zapol of Massachusetts General Hospital. They further said that:

Hydrogen sulfide is the stinky gas that can kill workers who encounter it in sewers; but when administered to mice in small, controlled doses, within minutes it produces what appears to be totally reversible metabolic suppression.

Carson Chow blogged about this in Scientific Clearing House back in 2005 with the following details:

When the mice were exposed to 80 ppm of H2S, their oxygen consumption dropped by 50% in the first 5 minutes. After 6 hours, their metabolic rate dropped by 90% and the core body temperature reached 15 degrees Celsius where the ambient temperature was 13 degrees. When the mice were returned to room air and temperature, their metabolic rate and body temperature returned to normal.

Wait, what’s suspended animation?

Good question. Suspended animation is the slowing of life processes by external means without termination. Breathing, heartbeat, and other involuntary functions may still occur, but they can only be detected by artificial means. (Wikipedia)

The dream, which has been a major subject of science fiction, is to cheat death by temporarily stopping the body’s natural clock, thereby delaying death and preserving the human body for some future purpose like space travel or enabling one’s self to see and experience what life on Earth would be like centuries from now.

In the real world, suspended animation has its practical uses in the medical field. In particular suspended animation induced by hypothermia is an alternative to heart-lung machines in some open-heart surgeries. Another use is the preservation of living organs that would have to be transported over long distances to where patients need them.

Where do mice and Hydrogen sulfide come in?

Using gases falls under the chemical-induced suspended animation and it doesn’t cause brain or tissue damage as do hypothermia, which is temperature-induced suspended animation.

Ever since mice were put to suspended animation thanks to Hydrogen sulfide, it could also be used in larger mammals and eventually humans, in theory. This is exactly what scientists did. They moved on to sheep, because hey, if it will work in sheep there is greater chance it would also work in humans.

And why not? The possibilities were simply hard to resist. Again Carson Chow wrote:

If this works in humans, we may now have a means of reducing metabolic demand after traumatic injury or surgery. H2S may become a standard part of the repertoire of paramedics. I won’t bother to dwell on the space travel implications.

Unfortunately, the idea never worked on larger mammals as tests in sheep as conducted by Haouzi et al. had discouraging results. Aschwin de Wolf writing in Depressed Metabolism put it straightforwardly: “Hydrogen sulfide does not induce hypometabolism in sheep

How can H2S induce hypometabolism in mice? The authors state that “the present results have little to offer on the pathways that are responsible for H2S-induced decrease of metabolism.” They raise the point that in small animals such as mice a large portion of metabolism is devoted to heat production instead of ATP production. In contrast, small reductions in oxygen utilization in humans, as produced by H2S exposure, will affect ATP generation. Or as Ikaria’s Csaba Szabo speculates in “Hydrogen sulphide and its therapeutic potential”, “the window of opportunity to compromise oxidative phosphorylation in a human, therefore, must be smaller than in the mouse.“

The authors do not expect that higher dosages of H2S will produce hypometabolism in large mammals because the 60 ppm that was administered to sheep already exceeds what is known to be toxic in humans.

So now the search for safe and effective means of inducing hypometabolism in humans goes on. The “fountain of life” remains to be an product of our desire for immortality and the Hydrogen sulfide will remain as such, smelling like rotten-eggs and in large doses, deadly to us humans.

One Reply to “Of mice, men and the fountain of life”

  1. Well it's not really much of a fountain of youth, if you have to spend eternity as a meat popcicle. But it could improve the wait time on holidays to other worlds.

Leave a Reply