Objective To summarize the function of Kupffer cell for the ischemia reperfusion injury after liver’s transplatation. Methods The literatures which about the function of Kupffer cell for the ischemia reperfusion injury after liver’s transplatation were reviewed. Results Kupffer cells are the resident macrophages of the liver, which can be activated to generate a range of inflammatory mediators, including cytokines, reactive oxygen intermediates, chemokines, and other factors to startup the ischemia reperfusion injury （IRI）, and to cause the liver graft dysfunction. On the other hand, Kupffer cells can protect the ischemia reperfusion injury by release NO and HO-1. The CO, which is the byproduct of heme degradation by the heme oxygenases （HO-1），has the same function for IRI. Conclusions The Kupffer cells have bidirectional function for the ischemia reperfusion injury of liver’s transpatation. Thus, how to decrease the harmful factors and up-regulate the beneficial substances by Kupffer cells will be the key points in preventing IRI after liver transplantation in future.
目的研究依达拉奉影响肝脏缺血再灌注过程中TNF-α的表达情况，探讨依达拉奉对肝脏缺血再灌注损伤的逆转作用。 方法将80只Wistar大鼠编号，根据计算机产生随机数字，前40为一组，后40为一组，分为实验组和对照组2组，建立常温下部分肝缺血再灌注损伤动物模型。 在肝脏缺血再灌注损伤开始前1 h和开始时对实验组大鼠给予依达拉奉注射液10 ml，对照组则给予同等容量的生理盐水。分别于再灌注后0、1、2及4 h测定肝脏脂质过氧化物酶（LPO）和肝脏谷草转氨酶(AST) 浓度； 应用RT-PCR法检测肝组织TNF-α mRNA含量，并测定肝组织和血清中TNF-α水平； 应用TUNEL染色法检测缺血肝组织的细胞凋亡情况。结果再灌注后1、2及4 h，实验组大鼠肝脏LPO及AST浓度均明显低于对照组（Plt;0.001）； 实验组再灌注后1 h时肝组织TNF-α mRNA表达量、肝组织和血清TNF-α含量均明显升高且达峰值，但均明显低于对照组（Plt;0.05）； 再灌注后各时相实验组肝细胞凋亡率明显升高，但均明显低于对照组（Plt;0.05）。 结论依达拉奉能抑制氧化应激反应，从而降低肝缺血再灌注损伤； 并显著减少炎性细胞因子TNF-α的产生，抑制炎性反应的发生，减少肝细胞的凋亡。
ObjectiveTo investigate the effect of simulated in vivo physiological environment severed limb fostering system applying remote ischemic conditioning (RIC) perfusion on preserving severed limb. MethodEighteen adult Bama mini pigs (24-30 kg in weight) were randomly divided into 3 groups (n=6) . No ischemic treatment was given in group A as normal control group; the right lower limbs were completely amputated and preserved at room temperature for 3 hours to make ischemic models in groups B and C, and then the severed limbs were put into the simulated in vivo physiological environment severed limb fostering system. Continuous blood perfusion was performed in group B, and continuous blood perfusion was performed after RIC perfusion in group C. After 8 hours of perfusion, the skeletal muscle samples were harvested for the morphology observation by transmission electron microscopy. The protein levels of B-cell lymphoma-2(Bcl-2) and Caspase-3 were detected by Western blot. The content of cytochrome C in both mitochondria and cytoplasm was determined by ELISA. ResultsTransmission electron microscopy results illustrated that the muscle fibers arranged more orderly and the mitochondria swelling was slighter in group C than group B. Western blot analysis showed that the protein levels of Bcl-2 and Caspase-3 were significantly higher in groups B and C than group A (P<0.05) ; the protein level of Bcl-2 significantly increased and the protein level of Caspase-3 significantly decreased in group C when compared with those in group B (P<0.05) . ELISA detection implicated that mitochondrial cytochrome C significantly reduced and cytosolic cytochrome C significantly increased in group B when compared with those in groups A and C (P<0.05) , but no significant difference was found between group A and group C (P>0.05) . ConclusionsThe ischemia/reperfusion-induced injury to skeletal muscle could be considerably inhibited by RIC perfusion. The simulated in vivo physiological environment severed limb fostering system applying RIC perfusion can significantly prolong the severed limb preserving time.
This prospective animal study was designed to investigate the changes of plasma endothelin (ET) levels in acute necrotizing pancreatitis (ANP). Sprague-Dawley rats were randomly devided into 3 groups: acute necrotizing pancreatitis (ANP) group in which ANP was induced by infusion of 5% sodium taurocholate (STC) into biliopancreatic duct, sham operation (SO) group and platelet activating factor antagonist BN50739 (BN) group. Blood levels of ET and platelet activating factor (PAF) were detected. Pancreatic microcirculatory blood flow was measured and pancreatic histological scores were evaluated. Results showed that the pancreatic microcirculatory blood flow in ANP group was decreased to a great extent immediatly after induction of ANP and soon began to rise slowly for 3 hours and again decreased steadily after that. The blood levels of ET, PAF and histological scores in ANP group were significantly higher than those in SO group. In BN group, the blood flow was significantly improved and the levels of blood ET, PAF and histological scores were all significantly lower as compared to those in ANP group. It is concluded that ischemia/ reperfusion is present in the initiation of acute necrotizing pancreatitis induced by STC in the rat. This leads to injuries of endothelial cells and increase in the production of ET and PAF. I/R lesions,and interaction of ET and PAF lead to a vicious circle, thus augmenting the pathological changes in the pancreas.
Objective To study the protective effects of pre-storing glycogen on warm ischemia reperfusion injury during partial hepatectomy. Methods Thirty-eight patients were randomly divided into a trial group (n=19) and a control group (n=19). In the trial group, patients were given high concentration glucose intravenously during the 24 hours before the operation. The hepatic lesion was resected after portal triad clamping in the two groups. Liver function of all patients was measured before the operation and the first and fifth days after the operation. Normal hepatic tissue was biopsied to measured hepatic tissue glycogen contents before the operation and the change of superoxide dismutase (SOD) at the point of pre-ischemia, post-ischemia, and reperfusion 2 hour. Bcl-2 mRNA, a well known anti-apoptotic factor, was also detected using quantitative polymerase chain reaction. Results The hepatic tissue glycogen content of the trial group was significantly higher than that of the control group before the operation (Plt;0.01). Liver function of the trial group was significantly better than that of the control group on the first and fifth day after operation (Plt;0.05). There was significant difference in SOD activity between the two groups at the end of hepatic vascular occlusion and at the point of 2-hour reperfusion (Plt;0.05). Furthermore Bcl-2 mRNA expression of the trial group was notably up-regulated at the point of 2-hour reperfusion compared to the control group. Conclusion Pre-store storing glycogen might protect liver ischemia reperfusion injury caused by hepatic vascular occlusion during partial hepatectomy. The potential mechanism might be that pre-storing glycogen enhances Bcl-2 expression.
Perfusion of free flaps from groin of rabbits, after 12 hours of complete ischemia, with superoxide dismutase (SOD), an oxygen free radical scavenger, would significantly increase the survival rate of these flaps from 18.75% to 75% in the control group. Tissue levels of SOD and malonydialdehyde (MDA, an end product of lipoperoxidation) were measured before ischemia, after ischemia but before reperfusion, and 60 minites after reperfusion. In untreated flap, after 12 hours- ischemia, the SOD content of skin decreased significantly as compared with the SOD content before ischemia, and reperfusion further decreased SOD activity, while the concentration of MDA increased after ischemia and further increased after reperfusion. In the treated flaps, the concentration of SOD was not decrease and MADnot increased after reperfusion. There was a negative correlation between the values of SOD and MDA. These findings suggested that free oxygen radicals playedan important role in the free flap ischemia reperfusion injury. SOD could increase the survival of ischemic free-flaps by reducing lipoperoxidation. The results had significant clinical implications with regard to organ preservation and transplantation.
Objective To collect and analyze published experimental and clinical studies about the protective function of ischemic preconditioning (IPC) to organs, in order to learn the history of IPC, the progress of experimental as well as clinical studies, and explore the mechanism of IPC in organ transplantation. Methods The electronic search of MEDLINE (1966 to Aug. 2009), EMbase (1974 to Aug. 2009) and The Cochrane Library (Issue 2, 2009) were performed to include and exclude the retrieved articles by two reviewers independently. The included studies were further treated for analysis and discriptive review. Results A total of 1 398 papers were included, of which about 75 percent were experimental studies, and only about 25 percent were clinical studies. About 73 percent studies focused on the heart and liver. Althrough the studies about the effects induced by IPC on the heart, brain, spinal cord and liver increased obviously in recent years, the clinical studies concerned the heart and liver operation and transplantation still far lagged behind experimental studies, especially very few clinical studies on the effect induced by IPC on kidney, lung, gastrointestinal tract and pancreas. Conclusion IPC intervention can effectively protect the heart and lung from the I/RI during the surgical and transplatational operations, and the hepat-surgical and living liver transplantational operations. IPC can effectively protect the brain and spinal cord from I/RI, but no protective function to cadaveric liver transplantation. However, the IPC effects on the kidney and gastrointestinal tract are not confirmed and neither is the mechanism of the effect induced by IPC.
Objective To study the efect of IH764-3 on ischemia-reperfusion (I/R) injury in rat liver. Methods Rats were divided into 3 groups, the control group was not subjected to ischemia and no treatment was given. I/R injury group was subjected to 40 minutes ischemia followed by reperfusion for 120 minutes. The IH7643 group (40mg/kg) was administred at ischemia and reperfusion. Results In the IH764-3 group, sereum levels of ALT, AST, AKP and γ-GT were significantly lower than those in the I/R group. Energy charge level recovery was significantly higher with IH7643 (P＜0.05), hepatic ultrastructure was better preserved with IH764-3. Conclusion IH764-3 may be useful in the treatment of hepatic ischemia reperfusion injury
Objective To study the interaction and mechanism of prostaglandin I2 (PGI2) receptor/thromboxane A2 (TxA2) receptor (IP/TP) and cyclooxygenase-2 (COX-2) in ischemia reperfusion injury after liver transplantation of rat. Methods Rats were randomly divided into three groups: control group （n=16), orthotropic liver transplantation group （n=32) and nimesulide intervention group （n=32). The samples were obtained at 3 h, 6 h, 12 h and 24 h after operation. The expressions of COX-2, IP and TP mRNA were detected by RT-PCR. Immunohistochemistry was used to detect the localization and expression of COX-2. Hematoxylin Eosin staining was used to classify the injury extent of liver. Serum ALT and AST levels were detected to evaluate the changes of liver enzyme. Results COX-2 protein expression detected by immunohistochemistry in orthotropic liver transplantation group mainly distributed in the district of liver sinusoidal endothelial cells, liver cells and macrophage cells, which was significantly higher than control group and nimesulide intervention group. Expressions of IP mRNA, TP mRNA and COX-2 mRNA in the orthotropic liver transplantation group were significantly increased than those in control group (P＜0.05), and the ratio of IP/TP increased (P＜0.05). Expressions of IP mRNA and TP mRNA in nimesulide intervention group were significantly lower than that in the orthotropic liver transplantation group at 6 h and 12 h after operation (P＜0.05), and the ratio of IP/TP decreased at 3 h, 6 h and 24 h after operation (P＜0.05). The expression of COX-2 mRNA in nimesulide intervention group was significantly lower than that in the orthotropic liver transplantation group at 6 h, 12 h and 24 h after operation. In orthotropic liver transplantation group liver injury was obvious by HE staining, and more severve than that in nimesulide intervention group. Serum AST (each time) and ALT (3 h, 6 h and 12 h) levels in the orthotropic liver transplantation group were significantly higher than that in control group and nimesulide intervention group (P＜0.05) and peaked at 6 h after operation. Conclusion The balance of IP/TP takes part in and plays an important role in the ischemia reperfusion injury of liver transplantation. Changing imbalance of IP/TP may reduce liver transplantation ischemia reperfusion injury by inhibiting COX-2 expression.
To investigate the role of platelet-activating factor (PAF), neutrophils in ischemia-reperfusion-induced liver injury and their possible mechanism, PAF and the degree of neutrophil infiltration in liver tissue and the preventive effects of PAF antagonist kadsurenone were evaluated in this study by means of a partial liver ischemia model, in which it was induced by clamping only left and median lobes of the liver without causing intestinal congestion. The present study was undertaken to find out the mechanism of liver ischemia-reperfusion injury and preventive effect of kadsurenone. The results indicate that in early stage of reperfusion liver injury possibly caused by the generation of free radicals, declined of autioxidant defence and increased Ca２＋ influx, and in the later stage of reperfusion injury was mainly mediated by accumulation of PAF in the liver, which elicits the release of polymorphonuclear leukocytes induced toxical free radical, endothelial damage, microcirculatory collapse. The authors conclude that the effectiveness of antagonist kadsurenone in protecting against ischemiareperfusioninduced liver injury is due not only to their action in preventing the direct effects of PAF, but also to their ability to inhibit both PAF priming and PAF dependent feedback processes, thus preventing escalation of auto generated inflammatory damage.