Biochemistry of Redox-Active Sulfur Compounds in Mammalian Cells and Approaches to Their Detection (A Review).

The discovery of new classes of regulatory molecules in human and animal metabolism always leads to a large-scale study of their properties in the context of biochemistry, physiology, and pharmacology. About 20 years ago, hydrogen sulfide (H2S) and its derivatives called reactive sulfur species (RSS), such as persulfides, polysulfides, nitrosothiols, sulfenic acids, and others became one of such classes of molecules. The participation of RSS in a variety of physiological and pathological processes, including the regulation of vascular tone, inflammation, long-term potentiation in the central nervous system, etc., has been shown. Changes in RSS levels or patterns of modification of their targets are associated with a wide range of cardiovascular, oncological, neurodegenerative, and other pathologies. For a part of these processes, mechanisms have been studied that involve direct modification of regulatory (NF-κB, Keap1) or effector (GAFD, eNOS, TRPA1) proteins through reactions of cysteine residues and metal-containing centers with APS. The presence of different regulated enzymatic systems producing RSS and numerous molecular targets allows us to consider H2S and its derivatives as an important class of small regulatory molecules. H2S is belongs to the class of so-called "gasotransmitters," along with nitric oxide (II) and carbon monoxide. Over the last 20 years, a vast amount of data on the biochemistry of these compounds and approaches to their study has been accumulated. [ABSTRACT FROM AUTHOR]