Hepatocyte protection by a protease inhibitor against ischemia/reperfusion injury of human liver

Systematic review of pathophysiological changes following hepatic resection

OBJECTIVES

Major hepatic resection is now performed frequently and with relative safety, but is accompanied by significant pathophysiological changes. The aim of this review is to describe these changes along with interventions that may help reduce the risk for adverse outcomes after major hepatic resection.

METHODS

The MEDLINE, EMBASE and CENTRAL databases were searched for relevant literature published from January 2000 to December 2011. Broad subject headings were 'hepatectomy/', 'liver function/', 'liver failure/' and 'physiology/'.

RESULTS

Predictable changes in blood biochemistry and coagulation occur following major hepatic resection and alterations from the expected path indicate a complicated course. Susceptibility to sepsis, functional renal impairment, and altered energy metabolism are important sequelae of post-resection liver failure.

CONCLUSIONS

The pathophysiology of post-resection liver failure is difficult to reverse and thus strategies aimed at prevention are key to reducing morbidity and mortality after liver surgery.

The effect of octreotide on hepatic ischemia-reperfusion injury in a rabbit model

BACKGROUND

Hepatic ischemic-reperfusion injury (HIRI) is a major cause of morbidity and mortality following liver surgery. Octreotide (Oct) has been reported to improve hepatocellular energy metabolism in a rat HIRI model. This study was designed to evaluate whether Oct could protect the liver of rabbits against ischemic-reperfusion (I/R) injury.

METHODS

Twenty-four adult New Zealand rabbits were randomly divided into a sham operated group (Control), an ischemia/reperfusion group (I/R), and an ischemia/reperfusion + Oct pretreatment group (I/R + Oct). The hemodynamic (mean arterial pressure [MAP] and heart rate [HR]) changes, liver enzymes (alanine aminotransferase [ALT], aspartate aminotransferase [AST], and lactate dehydrogenase [LDH]) release, inflammatory cytokines (tumor necrosis factor [TNF]α and interleukin [IL]-1β) levels, and endotoxin (ETX) levels were measured during I/R.

RESULTS

Compared with the Control group, the MAP decreased and HR increased in I/R and I/R + Oct groups at ischemia 15 minutes (P < .05) but were less in the I/R + Oct group relative to the I/R group (P < .05). ALT, AST, LDH, IL-1β, and ETX levels were increased in the I/R and I/R + Oct groups at ischemia 30 minutes (P < .05), however, the increase was lower in the I/R + Oct group relative to the I/R group (P < .05). Bcl-2 expression in the I/R + Oct group was higher compared with other groups (P < .05) and Bax expression in the I/R group was reduced compared with other groups (P < .05). Hepatocellular damage in the I/R + Oct group appeared to be less than in the I/R group by microscopy.

CONCLUSIONS

Oct pretreatment attenuated hemodynamic changes and decreased liver enzyme changes induced by HIRI in a rabbit model. The protection mechanisms of Oct may be related to reduced ETX levels, down-regulation of the inflammatory cytokines TNFα and IL-1β, and inhibition of hepatocellular apoptosis, as well as the modulation of the mitochondrion-mediated Bcl-2/Bax apoptosis pathway. Based on our study it appears that Oct may be useful in decreasing liver injury after liver surgery and/or transplantation and may serve as a promising agent against HIRI.

Surrogate endpoints in liver surgery related trials: a systematic review of the literature

BACKGROUND

Although the safety of liver surgery has improved enormously, hepatic surgery continues to face challenging complications. Therefore, improvements supported by evidence-based guidelines are still required. The conduct of randomized controlled trials in liver surgery using dichotomous outcomes requires a large sample size. The use of surrogate endpoints (SEPs) reduces sample size but SEPs should be validated before use.

AIM

The aim of this review was to summarize the SEPs used in hepatic surgery related trials, their definitions and recapitulating the evidence validating their use.

METHOD

A systematic computerized literature search in the biomedical database PubMed using the MeSH terms 'hepatectomy' or 'liver resection' or 'liver transection' was conducted. Search was limited to papers written in the English language and published between 1 January 2000 and 1 January 2010.

RESULTS

A total of 593 articles met the search terms and 49 articles were included in the final selection. Standard biochemical liver functions tests were the most frequently used SEP (32 of 49 the studies). The used definitions of SEPs varied greatly among the studies. Most studies referred to earlier published material to justify their choice of SEP. However, no validating studies were found.

CONCLUSION

Many SEPs are used in liver surgery trials however there is little evidence validating them.

Innovations in organ donation

The growing disparity between organ availability for transplantation and the number of patients in need has challenged the donation and transplantation community of practice to develop innovative processes, ideas, and techniques to bridge the gaps. Advances in the sharing of best practices in the donation community have contributed greatly over the last 8 years. Broader sharing of updated guidelines for declaration of brain death in conjunction with improvements in deceased donor management have increased opportunities for organ donation. New techniques for organ preservation and organ resuscitation have allowed for better utilization of the potential donor pool. This review will highlight processes, ideas, and techniques in organ donation.

Is close monitoring in the intensive care unit necessary after elective liver resection?

Purpose

Many surgical patients are admitted to the intensive care unit (ICU), resulting in an increased demand, and possible waste, of resources. Patients who undergo liver resection are also transferred postoperatively to the ICU. However, this may not be necessary in all cases. This study was designed to assess the necessity of ICU admission.

Methods

The medical records of 313 patients who underwent liver resections, as performed by a single surgeon from March 2000 to December 2010 were retrospectively reviewed.

Results

Among 313 patients, 168 patients (53.7%) were treated in the ICU. 148 patients (88.1%) received only observation during the ICU care. The ICU re-admission and intensive medical treatment significantly correlated with major liver resection (odds ratio [OR], 6.481; P = 0.011), and intraoperative transfusions (OR, 7.108; P = 0.016). Patients who underwent major liver resection and intraoperative transfusion were significantly associated with need for mechanical ventilator care, longer postoperative stays in the ICU and the hospital, and hospital mortality.

Conclusion

Most patients admitted to the ICU after major liver resection just received close monitoring. Even though patients underwent major liver resection, patients without receipt of intraoperative transfusion could be sent to the general ward. Duration of ICU/hospital stay, ventilator care and mortality significantly correlated with major liver resection and intraoperative transfusion. Major liver resection and receipt of intraoperative transfusions should be considered indicators for ICU admission.

Erythropoietin ameliorates renal ischemia and reperfusion injury via inhibiting tubulointerstitial inflammation

BACKGROUND

Tubulointerstitial inflammation is the characteristics of renal ischemia reperfusion injury (IRI) that is inevitable in kidney transplantation. Erythropoietin (EPO) has recently been shown to have protective effects on renal IRI by anti-apoptosis and anti-oxidation. Here, the effect and mechanism of EPO on renal IRI were further investigated, with a focus on tubulointerstitial inflammation.

MATERIALS AND METHODS

Male Sprague-Dawley rats were administrated with saline or EPO prior to IRI induced by bilateral renal pedicle clamping. Twenty-four hours following reperfusion, the effects of EPO on renal IRI were assessed by renal function and structure, tubulointerstitial myeloperoxidase (MPO) positive neutrophils, and proinflammatory mediator gene expression. The translocation and activity of NF-κB in renal tissues were also evaluated.

RESULTS

Compared with control groups, the EPO treated group exhibited lower serum urea and creatinine levels, limited tubular necrosis with a lower score of renal histological lesion. MPO positive cells in the tubulointerstitial area were greatly increased by IRI, but significantly reduced by the treatment of EPO. The gene expression of proinflammatory cytokines (IL-1β, IL-6, IL-10, and TNF-α) and chemokine (MCP-1) was also significantly decreased by EPO. In addition, less activation and nuclear-translocation of NF-κB was observed in the kidney treated by EPO as well.

CONCLUSION

EPO improved renal function and structure in IRI rats via reducing neutrophils in the tubulointerstitium, the production of proinflammatory cytokines and chemokine, as well as the activation and nuclear-translocation of NF-κB. EPO may have potential clinical applications as an anti-inflammation agent clinically for a wide range of injury.

Systematic review of randomized controlled trials of pharmacological interventions to reduce ischaemia-reperfusion injury in elective liver resection with vascular occlusion

BACKGROUND

Vascular occlusion during liver resection results in ischaemia-reperfusion (IR) injury, which can lead to liver dysfunction. We performed a systematic review and meta-analysis to assess the benefits and harms of using various pharmacological agents to decrease IR injury during liver resection with vascular occlusion.

METHODS

Randomized clinical trials (RCTs) evaluating pharmacological agents in liver resections conducted under vascular occlusion were identified. Two independent reviewers extracted data on population characteristics and risk of bias in the trials, and on outcomes such as postoperative morbidity, hospital stay and liver function.

RESULTS

A total of 18 RCTs evaluating 17 different pharmacological interventions were identified. There was no significant difference in perioperative mortality, liver failure or postoperative morbidity between the intervention and control groups in any of the comparisons. A significant improvement in liver function was seen with methylprednisolone use. Hospital and intensive therapy unit stay were significantly shortened with trimetazidine and vitamin E use, respectively. Markers of liver parenchymal injury were significantly lower in the methylprednisolone, trimetazidine, dextrose and ulinastatin groups compared with their respective controls (placebo or no intervention).

DISCUSSION

Methylprednisolone, trimetazidine, dextrose and ulinastatin may have protective roles against IR injury in liver resection. However, based on the current evidence, they cannot be recommended for routine use and their application should be restricted to RCTs.

Pharmacological interventions versus no pharmacological intervention for ischaemia reperfusion injury in liver resection surgery performed under vascular control

BACKGROUND

Vascular occlusion to reduce blood loss is used during elective liver resection but results in significant ischaemia reperfusion injury. This, in turn, might lead to significant postoperative liver dysfunction and morbidity. Various pharmacological drugs have been used with an intention to ameliorate the ischaemia reperfusion injury in liver resections.

OBJECTIVES

To assess the benefits and harms of different pharmacological agents versus no pharmacological interventions to decrease ischaemia reperfusion injury during liver resections where vascular occlusion was performed during the surgery.

SEARCH STRATEGY

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until January 2009.

SELECTION CRITERIA

We included randomised clinical trials, irrespective of language or publication status, comparing any pharmacological agent versus placebo or no pharmacological agent during elective liver resections with vascular occlusion.

DATA COLLECTION AND ANALYSIS

Two authors independently identified trials for inclusion and independently extracted the data. We analysed the data with both the fixed-effect and the random-effects models using RevMan Analysis. We calculated the risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CI) based on intention-to-treat analysis or available case analysis.

MAIN RESULTS

We identified a total of 15 randomised trials evaluating 11 different pharmacological interventions (methylprednisolone, multivitamin antioxidant infusion, vitamin E infusion, amrinone, prostaglandin E1, pentoxifylline, mannitol, trimetazidine, dextrose, allopurinol, and OKY 046 (a thromboxane A2 synthetase inhibitor)). All trials had high risk of bias. There were no significant differences between the groups in mortality, liver failure, or perioperative morbidity. The trimetazidine group had a significantly shorter hospital stay than control (MD -3.00 days; 95% CI -3.57 to -2.43). There were no significant differences in any of the clinically relevant outcomes in the remaining comparisons. Methylprednisolone improved the enzyme markers of liver function and trimetazidine, methylprednisolone, and dextrose reduced the enzyme markers of liver injury compared with controls. However, there is a high risk of type I and type II errors because of the few trials included, the small sample size in each trial, and the risk of bias.

AUTHORS' CONCLUSIONS

Trimetazidine, methylprednisolone, and dextrose may protect against ischaemia reperfusion injury in elective liver resections performed under vascular occlusion, but this is shown in trials with small sample sizes and high risk of bias. The use of these drugs should be restricted to well-designed randomised clinical trials before implementing them in clinical practice.

Pharmacological interventions for ischaemia reperfusion injury in liver resection surgery performed under vascular control

BACKGROUND

Vascular occlusion used during elective liver resection to reduce blood loss results in significant ischaemia reperfusion (IR) injury. This in turn leads to significant postoperative liver dysfunction and morbidity. Various pharmacological drugs have been used in experimental settings to ameliorate the ischaemia reperfusion injury in liver resections.

OBJECTIVES

To assess the relative benefits and harms of using one pharmacological intervention versus another pharmacological intervention to decrease ischaemia reperfusion injury during liver resections where vascular occlusion was performed during the surgery.

SEARCH STRATEGY

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until January 2009.

SELECTION CRITERIA

We included randomised clinical trials, irrespective of language or publication status, comparing one pharmacological agent versus another pharmacological agent during elective liver resections with vascular occlusion.

DATA COLLECTION AND ANALYSIS

Two authors independently identified trials for inclusion and independently extracted data. We analysed the data with both the fixed-effect and the random-effects models using RevMan Analysis. We planned to calculate the risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CI) based on intention-to-treat analysis or available case analysis. However, all outcomes were only reported on by single trials, and meta-analysis could not be performed. Therefore, we performed Fisher's exact test on dichotomous outcomes.

MAIN RESULTS

We identified a total of five randomised trials evaluating nine different pharmacological interventions (amrinone, prostaglandin E1, pentoxifylline, dopexamine, dopamine, ulinastatin, gantaile, sevoflurane, and propofol). All trials had high risk of bias. There was no significant difference between the groups in mortality, liver failure, or perioperative morbidity. The ulinastatin group had significantly lower postoperative enzyme markers of liver injury compared with the gantaile group. None of the other comparisons showed any difference in any of the other outcomes. However, there is a high risk of type I and type II errors because of the few trials included, the small sample size in each trial, and the risk of bias.

AUTHORS' CONCLUSIONS

Ulinastatin may have a protective effect against ischaemia reperfusion injury relative to gantaile in elective liver resections performed under vascular occlusion. The absolute benefit of this drug agent remains unknown. None of the drugs can be recommended for routine clinical practice. Considering that none of the drugs have proven to be useful to decrease ischaemia reperfusion injury, such trials should include a group of patients who do not receive any active intervention whenever possible to determine the pharmacological drug's absolute effects on ischaemia reperfusion injury in liver resections.

Preconditioning, organ preservation, and postconditioning to prevent ischemia-reperfusion injury to the liver

Ischemia and reperfusion lead to injury of the liver. Ischemia-reperfusion injury is inevitable in liver transplantation and trauma and, to a great extent, in liver resection. This article gives an overview of the mechanisms involved in this type of injury and summarizes protective and treatment strategies in clinical use today. Intervention is possible at different time points: during harvesting, during the period of preservation, and during implantation. Liver preconditioning and postconditioning can be applied in the transplant setting and for liver resection. Graft optimization is merely possible in the period between the harvest and the implantation. Given that there are 3 stages in which a surgeon can intervene against ischemia-reperfusion injury, we have structured the review as follows. The first section reviews the approaches using surgical interventions, such as ischemic preconditioning, as well as pharmacological applications. In the second section, static organ preservation and machine perfusion are addressed. Finally, the possibility of treating the recipient or postconditioning is discussed.

Feasibility of randomized controlled trials in liver surgery using surgery-related mortality or morbidity as endpoint

BACKGROUND

There is a shortage of randomized controlled trials (RCTs) on which to base guidelines in liver surgery. The feasibility of conducting an adequately powered RCT in liver surgery using the dichotomous endpoints surgery-related mortality or morbidity was examined.

METHODS

Articles published between January 2002 and November 2007 with mortality or morbidity after liver surgery as primary endpoint were retrieved. Sample size calculations for a RCT aiming to show a relative reduction of these endpoints by 33, 50 or 66 per cent were performed.

RESULTS

The mean operative mortality rate was 1.0 per cent and the total morbidity rate 28.9 per cent; mean rates of bile leakage and postresectional liver failure were 4.4 and 2.6 per cent respectively. The smallest numbers of patients needed in each arm of a RCT aiming to show a 33 per cent relative reduction were 15 614 for operative mortality, 412 for total morbidity, 3446 for bile leakage and 5924 for postresectional liver failure.

CONCLUSION

The feasibility of conducting an adequately powered RCT in liver surgery using outcomes such as mortality or specific complications seems low. Conclusions of underpowered RCTs should be interpreted with caution. A liver surgery-specific composite endpoint may be a useful and clinically relevant solution to pursue.

Clamping techniques and protecting strategies in liver surgery

The use of vascular occlusion during liver resection is still a matter of debate. The aim of this review was to assess the advantages and disadvantages of portal triad occlusion as a protective strategy during elective liver resection and liver transplantation. Newer strategies such as pharmacological preconditioning are also discussed. A systematic literature search was conducted to detect randomized controlled trials assessing the effectiveness and safety of portal triad clamping, ischaemic preconditioning and pharmacological preconditioning during liver surgery. Vascular clamping cannot be systematically recommended. When used, portal triad clamping is associated with a tendency towards reduced blood loss and blood transfusion without having an impact on morbidity. Intermittent clamping appears to be better tolerated than continuous clamping, especially in patients with chronic liver disease. Ischaemic preconditioning before continuous portal triad clamping reduces reperfusion injury after warm ischaemia, particularly in steatotic patients. Ischaemic preconditioning has unclear effects in transplantation and there is currently no evidence to support or refute the use of ischaemic preconditioning in the donor. There are emerging alternative conditioning strategies, including the use of volatile anaesthetics, which may provide new and easily applicable therapeutic options to protect the liver.

Molecular mediators of liver ischemia and reperfusion injury: a brief review

Ischemia and reperfusion injury is a dynamic process that involves multiple organ systems in various clinical states including transplantation, trauma, and surgery. Research into this field has identified key molecular and signaling players that mediate, modulate, or augment cellular, tissue, and organ injury during this disease process. Further elucidation of the molecular mechanisms should provide the rationale to identify much-needed novel therapeutic options to prevent or ameliorate organ damage due to ischemia and reperfusion in clinics.

Role of neutrophils in acute inflammatory liver injury

Hepatic infiltration of polymorphonuclear leukocytes (neutrophils) is an early response to tissue injury, cellular stress or systemic inflammation. Neutrophil activation is vital for host-defense and the removal of cell debris but can also cause additional tissue damage or even liver failure. In order to prevent the detrimental effects of neutrophils without compromising host-defense reactions, it is important to understand the mechanisms of neutrophil hepatotoxicity. The first step in the pathophysiology is the priming and recruitment of neutrophils into the liver vasculature by inflammatory mediators, e.g. cytokines, chemokines, or complement factors. Most critical for parenchymal cell damage is the accumulation in sinusoids, which does not depend on cellular adhesion molecules. The next step is the extravasation into the parenchyma. This process requires a chemotactic signal from hepatocytes or already extravasated neutrophils and depends on cellular adhesion molecules on neutrophils (beta(2) or beta(1) integrins) and on endothelial cells (intercellular or vascular cell adhesion molecules). The third step is the direct contact with target cells (hepatocytes), which involves beta(2) integrins and triggers the full activation of the neutrophil with a long-lasting adherence-dependent oxidant stress and degranulation. The oxidants diffuse into hepatocytes and trigger an intracellular oxidant stress, mitochondrial dysfunction and eventually cause oncotic necrotic cell death. Neutrophil-derived proteases facilitate extravasation and are involved in the regulation of inflammatory mediator production. Based on these mechanisms, it appears that strengthening of the intracellular defense mechanisms in hepatocytes may be the most promising therapeutic approach to selectively prevent neutrophil-mediated tissue damage without compromising their host-defense function.

Effects of gabexate mesilate on ischemia-reperfusion-induced testicular injury in rats

The aim of this study was to determine the effects of a synthetic serine protease inhibitor, gabexate mesilate (GM), in rats with ischemia-reperfusion (I-R) damage due to unilateral testicular torsion. Thirty male Sprague-Dawley rats were separated into three groups, each containing ten rats. A sham operation was performed in group 1 (control). In group 2 (I-R/untreated), 1 h detorsion of the testis was performed after 6 h of unilateral testicular torsion. In group 3 (I-R/GM), after performing the same surgical procedures as in group II, gabexate mesilate was given intravenously. In all experimental rats, ipsilateral orchiectomies were performed for histological examination and measuring the tissue levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px). MDA values and the testicular injury score decreased and SOD, CAT and GSH-Px values increased in the GM-treated group compared to the I-R/untreated group. The Tc-99m pertechnetate uptake ratio and the perfusion index were significantly decreased in the group 2 compared to the group 1 and 3 rats. In group 3, these values were significantly increased compared to group 2. Most of the specimens in the GM-treated group showed grade-I testicular injury. However, the injuries in the I-R/untreated rats varied between grade-III and grade-IV. The results of this study show that GM may play a role in reducing the injury caused by I-R.

Evaluation of a protease inhibitor in the prevention of ischemia and reperfusion injury in hepatectomy under intermittent Pringle maneuver

BACKGROUND

The severity of ischemia and reperfusion (I/R) injury is an important determinant of patient outcome in hepatic surgery. The aim of this study was to investigate the efficacy of a protease inhibitor in alleviating I/R injury to human liver in the setting of hepatectomy under intermittent Pringle maneuver.

METHODS

Sixty patients who underwent liver resection under conditions of intermittent inflow occlusion were randomly assigned to 2 groups (n = 30 each) according to the use of a synthetic protease inhibitor (gabexate mesilate or GM). GM was administered intravenously at a dosage of 2.0 mg/kg/h starting 12 hours before surgery until postoperative day 2. Preoperative and intraoperative clinical variables and postoperative outcomes were evaluated. The plasma levels of a cytokine, interleukin (IL)-6, as well as laboratory biochemical liver function parameters were analyzed to evaluate hepatic I/R injury.

RESULTS

The 2 groups of patients were comparable with regard to hepatic inflow occlusion time, extent of liver resection, and background liver histology. The preoperative administration of GM (GM group) substantially alleviated hepatic I/R injury compared with the untreated control group; postoperative serum transaminase levels were significantly decreased in association with marked suppression of IL-6 levels in blood circulation during surgery. This was accompanied by a lower incidence of postoperative complications. The patients without postoperative complications had significantly lower activities of plasma IL-6 at 24 hours after surgery.

CONCLUSIONS

This prospective randomized study demonstrated the hepatoprotective effect of a synthetic protease inhibitor in the setting of hepatectomy under the intermittent Pringle maneuver.

Drugs to facilitate recovery of neuromuscular blockade and muscle strength

Several drugs that quicken recovery from neuromuscular blockade caused by vecuronium in anesthetized patients are reviewed. Ulinastatin, a protease inhibitor, is thought to promote the release of acetylcholine at the neuromuscular junction and increases hepatic blood flow and urine volume. For this reason, ulinastatin quickens recovery from neuromuscular blockade in anesthetized patients receiving vecuronium. Additionally, pretreatment with ulinastatin avoids prolongation of vecuronium-induced neuromuscular blockade in patients with hepatic cirrhosis. Gabexate mesilate is also a protease inhibitor. During a continuous infusion of gabexate mesilate, recovery from neuromuscular blockade was quickened. Amino acid-enriched solution supplies energy to the skeletal muscles and causes an increase in muscle strength. An infusion of amino acid-enriched solution hastens recovery from neuromuscular blockade in anesthetized patients. When amino acids supply energy to the skeletal muscles, they simultaneously produce heat in the skeletal muscles. This thermal generation may be closely related to fast recovery from neuromuscular blockade. Amino acid-enriched solution makes recovery from neuromuscular blockade quick and avoids hypothermia during general anesthesia. Milrinone, a phosphodiesterase III inhibitor, is supposed to increase the release of acetylcholine at the neuromuscular junction and make the neuromuscular junction sensitive to acetylcholine. Therefore, recovery from neuromuscular blockade is hastened. Nicorandil enhances membrane K+ conductance in skeletal muscle and increases contraction of the skeletal muscle. Thus, nicorandil quickens recovery from neuromuscular blockade.

A case report of split liver transplantation for two adult recipients in Korea

We report a case of split liver transplantation (SLT) for two adult recipients, which was the first successful case in Korea. The brain-dead donor was a 22-year-old man weighing 65 kg, but his liver volume was estimated as 2120 mL on computed tomographic volumetry. As it seemed to be too large for a 60-kg recipient candidate, SLT was planned after assessment of lobar liver volume and middle hepatic vein anatomy. The right lobe was mobilized first and the liver parenchyma transected along the right border of the middle hepatic vein. The 1240-g right lobe (segments 5 to 8) graft was implanted into a 57-year-old male patient with acute-on-chronic liver failure in the same manner as a living-donor graft. After that, routine procedures of cadaveric multiorgan procurement were performed. The 670-g left lobe (segments 1 to 4) with a retrohepatic vena cava, common bile duct, and aortic patch was implanted into another 37-year-old male recipient. These two recipients recovered uneventfully surviving 12 months to date. We integrated the surgical techniques learned from hundreds of adult-to-adult living donor liver transplants into this first trial of two adult SLT.

Antioxidative effect of a chymotrypsin inhibitor fromMomordica cochinchinensis (Cucurbitaceae) seeds in a primary rat hepatocyte culture

The antioxidative activity of a chymotrypsin-specific potato type I inhibitor from Momordica cochinchinensis (MCoCI) (Cucurbitaceae) has been investigated using the primary rat hepatocyte system. tert-Butyl hydroperoxide (t-BHP) was used to induce oxidative stress. Pretreatment of hepatocytes with MCoCI for 24 h significantly reversed t-BHP-induced cell damage, and the associated glutathione depletion and lipid peroxidation. The activities of glutathione-S-transferase and superoxide dismutase were also increased. These results suggested that MCoCI possessed antioxidative activity which may account for some of the pharmacological effects of Momordica cochinchinensis seeds, the traditional Chinese medicine known as Mubiezhi, from which MCoCI was isolated.

Protective effects of tumor necrosis factor α antibody and ulinastatin on liver ischemic reperfusion in rats

AIM: To study the protective effects of tumor necrosis factor α (TNF α ) antibody and ulinastatin on liver ischemic reperfusion in rats.

METHODS: One hundred and twenty male SD rats were randomly divided into four groups: Normal control group, ischemic group, TNFα antibody group and TNFα antibody + ulinastatin group. The animals were killed at 0, 3, 6, 9, 12 h after ischemia for 60 min and followed by reperfusion. Serum alanine aminotransferase (ALT), malondialdehyde (MDA) and liver histopathology were observed.

RESULTS: After ischemic reperfusion, the serum ALT and MDA were remarkably increased, and the hepatic congestion was obvious. Treatment of TNFα antibody and ulinastatin could significantly decrease serum ALT and MDA levels, and relieve hepatic congestion.

CONCLUSION: Ulinastatin and TNFα antibody can suppress the inflammatory reaction induced by hepatic ischemic reperfusion, and have protective effects on rat hepatic ischemic reperfusion injury.

Molecular mechanisms of hepatic ischemia-reperfusion injury and preconditioning

Ischemia-reperfusion injury is, at least in part, responsible for the morbidity associated with liver surgery under total vascular exclusion or after liver transplantation. The pathophysiology of hepatic ischemia-reperfusion includes a number of mechanisms that contribute to various degrees in the overall injury. Some of the topics discussed in this review include cellular mechanisms of injury, formation of pro- and anti-inflammatory mediators, expression of adhesion molecules, and the role of oxidant stress during the inflammatory response. Furthermore, the roles of nitric oxide in preventing microcirculatory disturbances and as a substrate for peroxynitrite formation are reviewed. In addition, emerging mechanisms of protection by ischemic preconditioning are discussed. On the basis of current knowledge, preconditioning or pharmacological interventions that mimic these effects have the greatest potential to improve clinical outcome in liver surgery involving ischemic stress and reperfusion.