A novel method of preserving cardiac grafts using a hydrogen-rich water bath

Methods: The study used an established rat heterotopic transplantation model. Syngeneic heart grafts from elderly donors (60- to 70-week-old Lewis rats) or allografts from adult donors (12-week-old Brown Norway rats) were exposed to prolonged cold preservation. The cardiac grafts were stored in plastic bags containing Celsior, which were immersed in the cold water bath equipped with an electrolyzer to saturate the water with hydrogen. The cardiac grafts then were heterotopically engrafted into Lewis rat recipients.

Results: In both experimental settings, serum troponin I and creatine phosphokinase were markedly elevated 3 hours after reperfusion in the control grafts without hydrogen treatment. The grafts exhibited prominent inflammatory responses, including neutrophil infiltration and the upregulation of messenger RNAs for pro-inflammatory cytokines and chemokines. Myocardial injury and inflammatory events were significantly attenuated by organ storage in the hydrogen-rich water bath. The grafts stored using the hydrogen-rich water bath also exhibited less mitochondrial damage and a higher adenosine triphosphate content. Conclusions: Hydrogen delivery to cardiac grafts during cold preservation using a novel hydrogen-supplemented water bath efficiently ameliorated myocardial injury due to cold ischemia and reperfusion. This new device to saturate organs with hydrogen during cold storage merits further investigation for possible therapeutic and preventative use during transplantation.