Fig. 27.
Therapeutic effects of H2S donors and H2S biosynthesis inhibitors: a simplified overview. Some pathophysiological states are associated with H2S deficiency; this can be corrected by H2S donors (a form of replacement therapy) (left side). Other pathophysiological states are associated with H2S overproduction; this can be corrected by H2S biosynthesis inhibitors (right side). The scheme represents an oversimplification for a number of reasons. For example, the same pathophysiological condition can manifest itself with both H2S overproduction and H2S deficiency. In diabetes, the pancreatic beta cell destruction is linked to H2S overproduction; diabetes can also elevate H2S levels in the liver, with pathophysiological consequences. At the same time, the cardiovascular consequences of diabetes include vascular H2S deficiency, which contributes to vascular complications. In addition, in some diseases (e.g., cancer or burn injury), both systemic H2S biosynthesis inhibition and H2S donation can exert beneficial effects through different sets of biologic actions.