Effect of air-oxygenated normothermic mechanical perfusion on rat kidney recovery following ischemic injury from donation after cardiac death / 中华器官移植杂志

ABSTRACT

Objective:To develop an ex vivo normothermic mechanical perfusion(NMP)and compare the effect of air-oxygenated NMP versus oxygen-oxygenated NMP on reducing renal injury from donor after cardiac death(DCD).Methods:All kidneys from DCD rats were subjected to 30 min in situ warm ischemia after cardiac attest.And harvested kidneys were stored for 8h under static cold preservation after NMP for 2h.In experimental groups, kidneys were subjected to either air-oxygenated NMP(group A, n=6)or oxygen-oxygenated NMP(group O, n=6). Sham operation(group C, n=6)and DCD kidneys under static cold preservation without NMP(group SCS, n=6)were employed as controls.The evaluation parameters included creatinine(Cr), aspartate amino transferase(AST)and lactate dehydrogenase(LDH)in perfusate, pathological changes by hematoxylin-eosin(HE)staining, histological criteria, expressions of myeloperoxidase and intercellular adhesion molecular-1(ICAM-1)by immunohistochemistry and Western blot, tumor necrosis factor-alpha(TNF-α)and interleukin-6(IL-6)by enzyme-linked immunoadsorbent assay and level of malondialdehyde(MDA)by thiobarbital method and activity of superoxide dismutase(SOD)by WST-8 in renal tissues.Differences between two groups were analyzed by two-tailed unpaired Student's test and differences among more than two groups by one-way ANOVA.Results:Renal arterial oxygen tensions in NMP perfusate were(576.3±68.2)mmHg with oxygen-oxygenation and(137.0±39.1)mmHg with air-oxygenation.There was significant difference( P<0.05). The pathological injury scores in groups SCS, O and A by HE staining were(7.0±0.1), (5.0±0.9)and(2.5±0.5); injury scores and the expressions of renal proximal tubular epithelial cell vacuolar degeneration in groups O and A were lower than those in group SCS( P<0.05)and injury score in group A was lower than group O( P<0.05). In perfusate, the levels of △Cr, △AST and △LDH in groups O and A were(43.9±52.8)μmol/L and(12.6±3.5)μmol/L, (532.3±52.8)U/L and(49.1±50.4)U/L and(9998.0±2014.4)U/L and(1477.0±810.4)U/L.There were significant differences( P<0.05). In perfused kidneys, the MDA level and SOD activity in groups O and A were(0.192±0.018)mmol/g, (0.162±0.023)mmol/g, (0.6±0.3)×10 3 U/g, (1.7±0.4)×10 3 U/g; TNF-α and IL-6 levels in groups O and A were(124.376±19.635)and(89.331±13.123)ng/g, and(4.038±1.026)×10 3 and(1.774±0.518)×10 3 ng/g.After air-oxygenated NMP, lower renal damage indices were characterized by a lower MDA level and a higher SOD activity, the lower levels of TNF-α and IL-6 and the lower expressions of MPO and ICAM-1 than those in oxygen-oxygenated NMP( P<0.05). Conclusions:NMP with air-oxygenation mimics renal perfusion under physiological conditions and decreases oxidative stress and inflammation injury.It may confer a better retrieval in DCD kidney against warm ischemia injury.