Endogenous cyanide in life processes

This article examines the biological role and potential medical significance of endogenous hydrogen cyanide (HCN). Its exogenous analogs (hydrocyanide, sodium cyanide, potassium cyanide, etc.) were previously considered exclusively toxic to humans – lethal poisons. It addresses the toxic effects of exogenous cyanide compounds, the metabolism of endogenous cyanide in the body, and the regulation of hydrogen cyanide formation and breakdown in cells. It also examines methods for determining endogenous hydrogen cyanide levels in the body, the sites of action, and the mechanisms by which HCN influences individual vital processes in health and certain pathologies. Several studies have shown that both a deficiency and an excess of endogenous cyanides in the body can be associated with the onset and progression of various vital disorders. It has been demonstrated that by altering endogenous hydrogen cyanide levels in the body by influencing its synthesis and breakdown, it is possible to regulate metabolic reactions, physiological processes, and pathological processes. In this regard, various technologies are currently being developed to prevent and treat various life-threatening disorders using substances that regulate endogenous cyanide levels in the body. The diagnostic value of measuring endogenous hydrogen cyanide in exhaled air is being substantiated for various human respiratory diseases. Some researchers consider hydrogen cyanide, which is produced in the cells of bacteria, plants, animals, and humans, to be a universal regulatory factor, adding to the group of lowmolecular gaseous signaling biological regulators – gasotransmitters. Research in this area is rapidly gaining momentum.

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