Attenuation of ischemia-reperfusion injury in a canine model of autologous renal transplantation.

Background: This study examined the potential therapeutic effects of a combination therapy consisting of 5-aminoimidazole-4-carboxamide-1-beta-D-ribonucleoside (AICAR) and N-acetyl cysteine (NAC) to attenuate ischemia-reperfusion (I/R) injury in a canine model of autologous renal transplantation.

Methods: Male mongrel dogs (15-20 kg) underwent left nephrectomy followed by flushing and static preservation of the kidney in University of Wisconsin (UW) solution for 48 hr. The treatment group received AICAR (50 mg/kg) plus NAC (100 mg/kg) intravenously before the left nephrectomy. The compounds were added to the UW solution as well. All dogs underwent right nephrectomy 48 hr later followed by autotransplantation of the preserved left kidney. Treated dogs received a second dose of AICAR and NAC before implantation of the renal autograft.

Results: The treated dogs had excellent urine output posttransplant, with peak serum creatinine of 7.26 mg/dL on postoperative day (POD) 3 that normalized after 14 days. The control group were anuric and developed clinical symptoms of uremia on POD 1. Morphologic evaluation supported the protective effects of combination therapy. Immunohistochemical analysis revealed decrease of tumor necrosis factor-alpha, interferon-gamma, and inducible nitric oxide synthase; and TUNEL assay showed decreased apoptosis in the treated group.

Conclusions: Combination therapy with AICAR and NAC attenuates renal I/R injury and improves the outcome of the transplanted kidney after prolonged cold preservation.