The double-edged role of hydrogen sulfide in the pathomechanism of multiple liver diseases

In mammalian systems, hydrogen sulfide (H(2)S)—one of the three known gaseous signaling molecules in mammals—has been found to have a variety of physiological functions. Existing studies have demonstrated that endogenous H(2)S is produced through enzymatic and non-enzymatic pathways. The liver is the body’s largest solid organ and is essential for H(2)S synthesis and elimination. Mounting evidence suggests H(2)S has essential roles in various aspects of liver physiological processes and pathological conditions, such as hepatic lipid metabolism, liver fibrosis, liver ischemia‒reperfusion injury, hepatocellular carcinoma, hepatotoxicity, and acute liver failure. In this review, we discuss the functions and underlying molecular mechanisms of H(2)S in multiple liver pathophysiological conditions.