Air-ventilated normothermic machine perfusion alleviates hepatic injury from DCD rat through CYP1A2

Background: Normothermic machine perfusion (NMP) could provide protection to organs from donation after circulatory death (DCD) before transplantation, and its molecular mechanism remains unclear. Our previous study discovered that the air-ventilated NMP confers a better DCD liver recovery than oxygen-ventilated NMP. The purpose in the current study was to investigate the protective mechanism of air-ventilated NMP in a rat model of DCD liver by metabolomics, and to select biomarker to predict liver function recovery.

Materials and methods: Peroxisome proliferator activator receptor-α (PPARα) agonist or antagonist was administered via the perfusion circuit in the air-ventilated NMP. Perfusate samples were taken for measurements of aminotransferases using standard biochemical methods, tumor necrosis factor-alpha and interleukin-6. Liver biopsies were allocated for detection of metabolomics, PPARα and cytochrome P450 1A2 (CYP1A2).

Results: Metabolomics analysis revealed the significant increased γ-linolenic acid and decreased adrenic acid during the air-ventilated NMP, indicating linoleic acid metabolism pathway was associated with a better DCD liver recovery; as a major enzyme involved in linolenic acid metabolism, CYP1A2 was found correlated with a less inflammation and better liver function with the air-ventilated NMP; PPARα agonist could increase CYP1A2 expression and activity, decrease inflammation response, and improve liver function with the air-ventilated NMP, while PPARα antagonist played the opposite.

Conclusion: Air-ventilated NMP confers a better liver recovery from DCD rats through the activated linoleic acid metabolism and CYP1A2 upregulation; CYP1A2 expression and activity might function as biomarker to predict DCD liver function recovery with NMP.