Sen and his team found that the immune cell interleukin 1I (IL-1I) prompts production of the short-lived gas hydrogen sulfide, impacting the brain cells' ability to use food and glucose. Sen referenced damage to the protein PSD95 which is essential to the framework of the synapses that connect brain cells and which get modified by the gas hydrogen sulfide.
Loss of PSD95 already is implicated in dementia as well as depression, anxiety disorders and addiction. IL-1Beta signaling in the brain plays a critical role in learning and memory however, the rapid accumulation that follows injury appears to have the opposite effect. But, as with IL-1I at high levels, hydrogen sulfide seems more bent on cell destruction.
"It is maintained at a threshold level in every tissue of our body," Sen says. "But when it increases, it produces adverse reactions."
"It kills a very important protein for synaptic plasticity. This is a completely novel mechanism," that he hopes will one day translate to a novel therapy for several neurodegenerative disorders as well as brain injury. Hydrogen sulfide is a poisonous, flammable and colourless gas with a characteristic odour of rotten eggs. It is also found in sewers, sewage treatment plants, pulp and paper industry, natural gas plants, petrochemical plants, coke oven plants, food processing plants and tanneries. The study appeared in the journal Molecular Cell.