Effects Of Ulinastatin On Liver Warm Ischemia Reperfusion Injury In Mice

Objective：In order to minimize the incidence of liver function failure ornonfunction which is caused by liver warm ischemia reperfusion injury(IRI) during the procedures of liver resection or liver transplantation, weemployed the mouse liver warm IRI model to extensively investigate theeffects of Ulinastatin (UTI) on protection of liver IRI and the underlyingmechanisms. The results from this study will guide the clinical therapy onprevention and treatment of liver IRI, and further explore the applicationof UTI in liver IRI.Materials and Method: Male C57BL/6mice，7-9weeks of age，weighing20-25g，were employed and randomly divided into3groups:Sham surgery (SO) group，IRI group，and UTI treatment (IRI+UTI) group.Mouse model of liver warm IRI and was established by Pringle claimingtechnique of clamping hepatoduodenale ligament for45minutes in roomtemperature. After45minutes of clamping, the clamp was removed andthe liver blood perfusion was restored. The mice were sacrificed at1hour，6hours，and24hours post reperfusion, respectively. The serum ALT,AST, and LDH levels were measured. The liver tissues were collected,H&E staining for histology examine, immunohistochemistry for cytokine IL-6and TNF-α production and TUNEL staining for apoptosis detection,and RT-PCR for Caspase-3and Fas mRNA detection, respectively.Result:1. UTI treatment significantly reduced the liver enzyme release.Serum ALT、AST、and LDH levels were remarkably reduced in IRI+UTIgroup than IRI group at all the time courses of reperfusion (P<0.05).2.UTI also preserved the liver morphology and architecture from IRI.Histological examine on H&E section revealed hepatocyte swelling,increased cytoplasmic vacuolization, nuclear pyknosis, sinusoidaldilatation, and focal necrosis after6hours reperfusion. In contrast, UTItreatment give better protection of liver histology.3. UTI significantlyinhibited the proinflammatory cytokine IL-6and tumor necrosis factor-α(TNF-α) production. IL-6and TNF-α positive cells of liver section weremuch higher in the IRI group than that in IRI+UTI group (P<0.05).4.UTI treatment prevented the hepatocyte from apoptotic death. TUNELstaining on liver section revealed that the number of apoptotic cells wasmuch reduced in the IRI+UTI group than IRI group (P<0.05).5. Finally,pro-apoptosis molecules Caspase-3and Fas mRNA levels were reducedsignificantly in IRI+UTI group compared to IRI control (P<0.05).Conclusion: UTI has the potential of inhibiting pro-inflammatorycytokine release, protecting the hepatocytes from apoptotic death, andfurther protecting the liver from warm IRI. The mechanisms of UTI onliver warm IRI may through blocking Caspase-3and Fas pathway, reduces the hepatocytes apoptosis, and further protects the liver from IRI.