Role of hydrogen sulfide in health and disease.

In the past, hydrogen sulfide (HS) was recognized as a toxic and dangerous gas; in recent years, with increased research, we have discovered that HS can act as an endogenous regulatory transmitter. In mammals, HS-catalyzing enzymes, such as cystathionine-β-synthase, cystathionine-γ-lyase, and 3-mercaptopyruvate sulfurtransferase, are differentially expressed in a variety of tissues and affect a variety of biological functions, such as transcriptional and posttranslational modification of genes, activation of signaling pathways in the cell, and metabolic processes in tissues, by producing HS. Various preclinical studies have shown that HS affects physiological and pathological processes in the body.