Addition of a liver to the normothermic perfusion circuit reduces renal pro-inflammatory factors

Background: Normothermic machine perfusion (NMP) provides a novel platform to preserve isolated organs in an artificial condition. Our study aimed to explore the interaction between the liver and kidney at an ex vivo organ level by adding a liver to the kidney NMP circuit. Methods: Porcine kidney and liver obtained from abattoir were subjected to 9 h NMP after suffering 30-min warm ischemia time and 90-min cold ischemia time. The liver–kidney NMP group (n = 5) and the single-kidney NMP group (n = 5) were designed. During the NMP, perfusion parameters, blood gas analysis, and tissue samples were compared. Results: The perfusate of both groups remained stable, and continuous urine production was observed during NMP. In the liver–kidney NMP group, the lactate level was low, while blood urea nitrogen increased and glucose levels decreased. After the NMP, the renal tissue in the liver–kidney group exhibited fewer histological changes such as tubular epithelium vacuolization, along with reduced expression of IL-6, IL-8, IL-1β, NLRP3, and GSDMD. Conclusions: Our results indicated that the expression of renal pro-inflammatory factors was reduced in the liver–kidney NMP system.