Catalytic metal ions and the loss of reduced glutathione from University of Wisconsin preservation solution

The University of Wisconsin solution is widely used for organ preservation. We show that this fluid is often contaminated by traces of iron catalytic for free radical reactions, as demonstrated by the bleomycin assay and the ability of the iron to stimulate lipid peroxidation. Reduced glutathione (GSH) added to University of Wisconsin solution during its commercial preparation had oxidized to the disulfide in all samples examined. Addition of GSH to UW solution showed its half-life to be about one day. The metal ion chelators desferrioxamine and phenanthroline did not substantially delay the loss of GSH, although desferrioxamine was able to suppress iron-mediated lipid peroxidation induced by the contaminant iron in the preservation solution. Additional iron was released from rat liver after a period of cold storage/rewarming.