From Lab to Life Key Role of Rotten Egg Gas

Consider H₂S,  hydrogen sulfide, or ‘rotten egg gas’.  It has killed miners in the past, even though it can be detected at low concentrations and thus initiate evacuation.

Hydrogen sulfide is historically called stinkdamp or sour damp by miners. It kills miners through rapid neurological paralysis, respiratory failure, and physical accumulation in underground spaces.  Miners often recognize it at low levels by its distinct rotten-egg odor. However, at higher concentrations, the gas quickly numbs or completely paralyzes the smelling nerves … making it undetectable by smell just when it becomes most lethal.

Now it emerges H₂S is a key ‘gaseous mediator’ for the brain, along with nitric oxide. It facilitates key processes related to memory.  It turns out our brain makes H₂S on purpose, every second – in order to think! (See ** for early research on this. (A Japanese researcher made this discovery first, as early as 1996 – 30 years ago!)

** Brain, Learning, and Memory: Role of H2S in Neurodegenerative Diseases,  V.S. Nagpure et al., Handbook of Experimental Pharmacology, 2015.

Turns out our brains can’t work properly without hydrogen sulfide.  Why?  How?  The brain, it seems, brews its own supply of hydrogen sulfide from one amino acid, ‘on demand’.  At our ‘synapses’  (the tiny gap between neurons),  “it turns the memory switch up”,  scientists found.

First, it strengthens the synaptic connections between brain cells in the hippocampus, site of long-term memories. Second, it helps control intracellular calcium concentrations in neurons, vital for normal signaling and healthy synapses.  Third, it influences how brain cells release chemical messengers—such as glutamate (which aids learning).  Fourth,  it supports blood-brain barrier integrity, that keeps bad stuff in our blood streams out of our brains.

Can H₂S be therapeutic, healing?  Yes!  Slow-release  compounds “can improve memory and cognitive deficits in animal models of Alzheimer’s disease and brain injury.”

The brain is truly an amazing organ. It can make crucial use of a gaseous compound that in high concentrations is lethal.