Identifying the role of cytochrome c in post-resuscitation pathophysiology

• Cytochrome c may initiate apoptosis.
• Cytochrome c may improve metabolic capacity and allow the cells to better withstand an injury.
• Cytochrome c may serve as a potential prognostic and therapeutic biomarker after cardiac arrest.

Cytochrome c, an electron carrier that normally resides in the mitochondrial intermembrane space, may translocate to the cytosol under ischemic and hypoxic conditions and contribute to mitochondrial permeability transition pore opening. In addition, reperfusion of brain tissue following ischemia initiates a cell death cascade that includes cytochrome c–mediated induction of apoptosis. Further studies are needed to determine the contribution of cytochrome c in the regulation of cell death, as well as its value as an in vivo prognostic marker after cardiac arrest and resuscitation.