Bone Morphogenetic Protein-7 Reduces Cold Ischemic Injury in Rat Kidney

Abstract

Background Deceased donor kidneys have a high incidence of delayed graft function attributable to ischemia–reperfusion injury. Although preservation solution and cold storage reduce cold ischemic injury, the depletion of cellular energy and oxidative signalling leads to cellular damage. Because bone morphogenetic protein-7 has renoprotective effect, we have hypothesized that recombinant human bone morphogenetic protein-7 (rh BMP-7) will better preserve kidney tissue exposed to prolonged cold ischemia in comparison with University of Wisconsin (UW) solution. We evaluated how the duration of cold ischemia influences the cold ischemic injury. Methods Levels of lipid peroxidation, protein carbonyl content, as well as superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were determined in the kidneys by spectrophotometry after 6, 12, and 24 hours of cold ischemia. Results Time-dependent increases in the levels of lipid peroxidation and protein carbonyl content at all time points were significantly lower in rhBMP-7–perfused kidneys versus the UW-treated group. SOD activity after 6 hours, as well as GSH-Px activity after 24 hours of cold ischemia was significantly higher in the kidney tissue perfused by rhBMP-7 than in UW group. Conclusion rhBMP-7 significantly decreases cellular damage in rat kidney versus UW preservation solution and this is attributed to lowering of cold ischemia injury and maintaining prolonged tissue antioxidant activity.