Caspase Inhibition Prevents the Increase in Caspase-3, -2, -8 and -9 Activity and Apoptosis in the Cold Ischemic Mouse Kidney

Abstract

Prolonged cold ischemic time is a risk factor for the development of delayed graft function. The adverse impact of cold ischemia may be associated with tubular cell death in the kidney. Caspase-3 is a major mediator of apoptotic cell death. We hypothesized that caspase inhibition would reduce apoptosis and other features of cold ischemia. Kidneys of C57BL/6 mice were perfused with cold University of Wisconsin solution containing a pancaspase inhibitor or vehicle via the left ventricle. The contralateral right kidney was used as a control. The left kidney was stored for 48 h at 4°C to produce cold ischemia. Caspase-3 activity was massively (100-fold) increased in cold ischemic kidneys compared with controls. On immunoblot analysis, the processed form of caspase-3 was increased in cold ischemic kidneys compared with controls. The increase in caspase-3 was associated with significantly more renal tubular apoptosis and brush-border injury. In addition, caspase-2, -8 and -9 activities were increased in cold ischemic kidneys. The pancaspase inhibitor prevented the formation of the processed form of caspase-3 and the increase in caspase activity, and reduced apoptosis and brush-border injury. Caspase inhibition may prove useful in kidney preservation.