Application Of EGCG In Perfusate In Improving Normothermic Oxygenated Machine Perfusion For Rat Steatotic Livers

Objective:? At present,there is no complete model of normothermic machine domestically,which limits the study of NMP.In this experiment,a novel rat model of NMP was established.?This study was designed to investigate whether NMP preservation with perfusate containing EGCG successfully protects>30%macrosteatotic rat livers.METHODS:1)It consists of peristaltic pump,oxygenator,reservoir,defoamer,temperature detector,pressure sensor,liver tank and bile collector.Through the perfusion of rat liver,the application of the system in oxygenated mechanie perfusion was evaluated.2)A rat model of fatty liver was established.Fatty liver rats were randomly divided into five groups:EGCG perfusion groups(NMP-Y groups)include 5mM,lOmM,20mM,30mM,perfusate control group(NMP group)and static cold storage group(SCS group).Rats'livers in the NMP-Y group and the NMP group were preserved by machine perfusion for 3 hours.SCS group was preserved by UW solution for 3 hours.The perfusate sample was collected at 10min,20min,30min,40min,50min,60min,90min,120min,150min,180min.Then the perfusate was centrifuged(2000 rpm,4?,5 minutes)and the supernatant was taken and placed at-80? for storage.Livers were divided into four parts and three of them were placed in the RNA preservation solution,formalin,frozen section preservation solution and one part was directly frozen.The contents of ALT,AST,TG,LDH were detected.Liver tissue examination:HE staining were performed to observe the liver morphology of steatotic livers.Liver tissue adipocytosis was detected by oil red staining.The amount of bile produced was calculated by weighing the cannular weight change before and after the perfusion.Results:The normothermic temperature oxygenated machine perfusion system of rat liver was successfully constructed in this study.The system can maintain the normothermic machine perfusion of rat liver for more than 3 hours.The liver perfused by the system can secrete bile,and the liver texture is soft which is better than the liver preserved by static cold storage.The changes of liver enzymes in the perfusion fluid of EGCG group were significantly lower than that of the control group,and the changes of triglycerides were significantly higher than that of the control group.The fatty change of liver in the 10 mM dose group was significantly improved compared with that in the control group.Conclusion:This study successfully established the rat liver normothermic oxygenated machine perfusion system.The application of EGCG in oxygenated machine perfusion of liver can significantly improve the degree of fatty liver.