Abstract
Cysteine is an amino acid with a thiol group in its side chain, and plays an essential role in maintaining the structure of proteins through disulfide bonds. It also acts as an antioxidant, and enzyme activity center within cells. In recent years, cysteine persulfide and polysulfides, in which a sulfur atoms are added to the cysteine thiol group, are abundantly present in cells as forms of glutathione and protein persulfides and polysulfides, and they have a wide variety of biological effects such as extremely strong antioxidant activity, anti-inflammatory effects, regulation of immune function, and control of energy metabolism. These diverse biological functions are not found in the original cysteine thiols, or are much stronger, so it is called a supersulfide, meaning that it has functions that exceed those of sulfides. Currently, the metabolism and functional regulation of supersulfides are attracting a great deal of attention worldwide as targets for new drug discovery and diagnosis. We are interested in the powerful anti-inflammatory effects of supersulfides. In this lecture, I would like to report on research results focusing on the control of inflammation by supersulfides, particularly on innate immune responses such as Toll-like receptors and inflammasomes. I would also like to discuss developments in the treatment of inflammatory diseases based on the anti-inflammatory effects of supersulfides.
