Cytoprotective actions of hydrogen sulfide in ischaemia-reperfusion injury

Hydrogen sulfide (H(2)S) has been known as a highly toxic gas for several centuries. There have been considerable advances made in the H(2)S field regarding its physiological role; however, there is much more work that needs to be done. The biosynthesis of H(2)S has been attributed to three endogenous enzymes: cystathionine β-synthase (CBS), cystathionine γ-lyase (CGL or CSE) and 3-mercaptopyruvate sulfurtransferase (3-MST). These enzymes require further investigation to more fully elucidate the cellular expression profile, regulation and precise role of these critical enzymes in the production of H(2)S. In recent years, H(2)S has been demonstrated to have cytoprotective effects in multiple organ systems. In particular, it has been demonstrated that the administration of H(2)S either prior to ischaemia or at reperfusion significantly ameliorates myocardial and hepatic ischaemia-reperfusion injury. Therefore, this review focuses on the cardioprotective and hepatoprotective role of H(2)S. In addition, the review provides a summary of several known molecular targets of H(2)S protection.