| Objective:Our country is one of countries with the higher morbidity of disease of the liver and bile duct, Surgery is the one of the most important treatment of them. Hepatic lobectomy is the most conventional and widely used method of the liver and biliary tract surgery.The main problem of liver resection is how to effectively control bleeding during the operation.Since 1908 the Pringle,s method of portal triad clamping has been widely uesed, there has been a variety of clinical methods, which mainly include: the first portal triad clamping, single portal triad clamping and total hepatic vascular exclusion.The applications of these methods can effectively control the bleeding, and also play an important role in reducing the opportunity for iatrogenic injury and reducing the incidence of surgical complications. However, hepatic inflow occlusion will undoubtedly bring warm ischemia injury to the liver. Accordingly, in clinical we pay more cautious to the time of hepatic vascular exclusion , generally appropriate for 10-15min, no more than 20min.Therefore, since the portal triad clamping method has been applied,the protection of liver against ischemia/reperfusion injury remains one of the major problems in liver surgery.With the modern advances in abdominal surgery,Liver transplantation is the main means as the treatment for end-stage liver disease. Our country is also one of countries with the higher morbidity of liver ailment and most large number of death of liver function failure in the world. Liver transplantation is developing quickly and number of patients performed liver transplantation is increasing in our country. Hepatic ischemia/reperfusion injury (IRI) is an important nonimmunologic factor and remains a significant problem and limitation of liver transplantation and may result in liver failure, remote organ failure, and even death. For this reason, the protection of liver against ischemia/reperfusion injury remains one of the major nonimmunologic problems of liver transplantation.The liver is a particularly sensitive to hypoxic-ischemic injury organ .It was known that hepatocellular anoxic glycolysis is the ATP-yielding source on which hepatocellular integrity and function are maintained during hepatic ischemia.Undoubtedly, a lack of hepatocellular ATP is a pivotal determinant in the pathogenesis of liver damage from hepatic ischemia . Once hepatocellular glucose is exhausted, anoxic glycolysis has no substrate and ATP depletion rapidly develops, leading to hepatocellular edema and necrosis.Our previous studies demonstrate that intracellular abundant glycogen can attenuate ischemia/reperfusion injury in rabits. GSK-βwas named based on its initial identification as a kinase that phosphorylates the glycogen-synthesizing enzyme, glycogen synthase . For many years GSK3 was relegated to this backwater area of glycogen metabolism. The recent finding that GSK3 is a powerful regulator of inflammation has increased the focus on this Ser/Thr kinase that was already characterized as having a tentacular capacity to influence numerous aspects of cell function,often acting as a centralized integrator of many intracellular signals(fig1). Based on these findings ,we propose that Glycogen synthase kinase-3βinhibition would be useful in the treatment of various ischaemia and reperfusion diseases.Based on the previous results,the present study explored the effect and mechanism of pre-storing glycogen and Glycogen synthase kinase-3βinhibition on hepatic ischemia/reperfusion injury; determined the effect of IRI on the expression of Bcl-2 gene, and examinated the effect of YS intervention on the expression of Bcl-2 gene.Methods:Rats partial hepatic warm ischemia/reperfusion model was used in this study.1. 3 groups of rats were randomly assigned to different dose of glucose injection followed by 70% portal ligation for 30 min. 10 rats from each group were sacrificed for harvest of serum and tissue sample at 1h, 4 h, 12h and 24 h after reperfusion, respectively. The hepatic function was measured and the morphological changes of the livers were examined. Bcl-2, a well known anti-apoptotic factor, was also detected using quantitative polymerase chain reaction.2. Rats were randomly divided into 3 groups:normal group,sham-operated group and ischemia-reperfusion group. The hepatic function was measured and the morphological changes of the livers were examined. The concentrations of TNF-αwas measured by radioimmunity technique and the hepatocellular apoptosis was detected by (TUNEL)and electron microscope. The expression of GSK-βwas measured by immunohistochemistry.3. Rats were randomly divided into 4 groups,group A(Sham +vehicle group), group B(Sham +TDZD-8), group C(I/R +vehicle) and group D(TDZD-8).Based on the model of total hepatic I/R injury in rats by 70% portal ligation for 30 min. 8 rats from each group were sacrificed for harvest of serum and tissue sample at 2 h and 12h after reperfusion, respectively. The hepatic function was measured and the morphological changes of the livers were examined. Bcl-2, a well known anti-apoptotic factor, was also detected using quantitative polymerase chain reaction.Result:1. The rats with higher glucose administration presented higher glycogen in hepatocytes and better hepatic function and the 1 week survival rate was increased. In histology, these rats showed slighter histological damage and lower apoptotic index. Furthermore, content,the morphological changes of the liver tissue were mild, the levels of ALT, AST and AI decreased( P<0.05), Bcl-2 mRNA expression was the strongest was notably upregulated after higher dose of glucose administration.2. The concentrations of the expression of GSK-βand hepatocellular apoptotic index(HAI)in ischemia-reperfusion group were higher than that in normal and sham-operated groups. Both TNF-αand HAI reached peak at 12hour after reperfusion. There was a positive correlation between GSK-βand HAI.3.The rats with GSK-3βinhibition administration presented better hepatic function. In histology, these rats showed slighter histological damage and lower apoptotic index. Furthermore the morphological changes of the liver tissue were mild, the levels of ALT, AST and AI decreased( P<0.05), Bcl-2 mRNA expression was the strongest was notably upregulated after administration.Conclusion:1. Pre-storing glycogen might protect liver impairment caused by ischemia reperfusion injury, and the potential mechanism might be that pre-storing glycogen enhance the Bcl-2 expression and prevent the hepatic cells from apoptosis.2. There is an extraordinary up-regulation of the expression of GSK-βafter hepatic ischemia-reperfusion and perhaps GSK-βis an inducible factor ofhepatocellular apoptosis.3.GSK-3βinhibition might protect liver impairment caused by ischemia reperfusion injury, and the potential mechanism might be that it enhance the Bcl-2 expression and prevent the hepatic cells from apoptosis.
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