Cardioprotective Effects of S-Nitrosothiols in Ischemia- Reperfusion: Role for Mitochondria and Calcium Channels

The most important clinical consequence of coronary disease is acute myocardial infarction caused by an occlusion that limits the irrigation to the heart. Although the gold standard treatment is to restore blood flow, this reperfusion causes inherent damage by increasing the size of the infarcted area primarily through the opening of the mitochondrial permeability transition pore (MPTP). The cardioprotective effect of nitric oxide (NO) has been described to operate through S-nitrosylation of several important proteins in the cardiomyocytes such as the calcium channels RyR2 and the L-type Ca2+ channel and mitochondrial proteins, including the MPTP. In this sense, an attractive strategy to prevent the ischemia-reperfusion damage is to increase the bioavailability of endogenous S-nitrosothiols. S-nitrosoglutathione reductase (GSNOR) is an enzyme involved in the metabolism of NO through denitrosylation, which would limit the cardioprotective effect of NO. Although inhibition of GSNOR has been studied in different organs, its effects on myocardial reperfusion have not yet been fully elucidated. In this chapter, we review the pathophysiology underlying myocardial reperfusion injury and the opening of the MPTP along with the cardioprotective role of S-nitrosothiols and the potential role for GSNOR