The 49th Congress of the European Society for Surgical Research May 21-24, 2014, Budapest, Hungary: Abstracts

2014 European Surgical Research  
Portal vein ligation (PVL) results in ipsilateral atrophy and hypertrophy of contralateral liver segments. It is unknown how PVL affects metabolic patterns of hepatic tissues. The aim of this study is to evaluate the effect of PVL on glucose metabolism, using multi-modal PET/MRI imaging in healthy rat liver. Material and Methods: Male Wistar rats (n=30) underwent PVL. 2-deoxy-2-(18F)fluoro-D-glucose (FDG) PET/MRI imaging and morphological/histological examination were performed before; 1-, 2-,
more » ... -, 7-days after PVL. Dynamic PET data were collected and the standardized uptake values (SUV) for ligated and non-ligated liver lobes were calculated in relation to cardiac left ventricle (SUVVOI/SUVCLV) and mean liver SUV (SUVVOI/SUVLiver). Result: PVL induced atrophy of ligated lobes, while non-ligated liver tissue showed compensatory hypertrophy. Dynamic PET scan revealed altered FDG kinetics in both ligated and non-ligated liver lobes. SUVVOI/SUVCLV significantly increased in both groups of lobes, with a maximal value at 2nd postoperative day and returned near to the baseline 7 days after the ligation. After PVL, ligated liver lobes showed significantly higher tracer uptake compared to the non-ligated lobes (significantly higher SUVVOI/SUVLiver values were observed at postoperative day 1, 2 and 3). The homogenous tracer biodistribution observed before PVL reappeared by 7th postoperative day. Conclusion: Our study demonstrated an altered glucose metabolism in both ligated and non-ligated liver lobes. The observed alterations in FDG uptake dynamics should be taken into account during the assessment of PET data until the PVL induced atrophic and regenerative processes are completed. Background: Pringle maneuver(PM) has been used widely to control blood loss during liver resection. However, hepatic inflow occlusion can also result in hepatic ischemiareperfusion injury (IRI), especially in patients with a cirrhotic liver. Nitric oxide(NO) is generated from NO synthase(NOS), and has not only cytoprotective but also cytotoxic effect. The aim of this study was to investigate the effect of the NOS inhibitor(L-NAME) on IRI after PM of cirrhotic livers induced by bile duct ligation(BDL). Material and Methods: Male Wistar rats were divided into three groups: sham group(non-BDL/no treatment), L-NAME group(BDL with L-NAME treatment) and BDL group(BDL/no treatment). Cirrhosis was induced by BDL. Two weeks after BDL, 50 % partial hepatectomy with PM was performed. The rats of L-NAME group were injected with L-NAME(1.5 mg/kg) 15 minutes before PM. We evaluated the hepatocellular damage, portal venous flow and microcirculation of the liver after reperfusion. Result: Although there was no significant difference in portal venous flow between L-NAME and BDL group, microcirculation of the liver in L-NAME group tended to be higher than that of BDL group (Table) . Histopathologically, the semiquantitative score for liver damage and apoptotic index were significantly lower in L-NAME group than in BDL group 168 hrs after reperfusion. Ki-67 labeling index of L-NAME group was significantly higher than that of BDL group 24 hrs after reperfusion. Conclusion: L-NAME attenuated IRI induced by Pringle maneuver, and improved microcirculation of cirrhotic livers. Microcirculation flow of the liver (AU) (Mean ± S.E.M.) Time after reperfusion (hr) L-NAME group BDL group 1 Background: Nox-derived reactive oxygen species (ROS) phosphorylate redox sensitive pathways facilitating metastasis. Mediators of surgery-induced inflammation including lipopolysaccharide (LPS) activate Nox enzymes. Surgery-induced inflammation is associated with accelerated tumour growth. Thus we aimed to characterise the potential role for Nox-derived ROS in enhancing metastatic colonisation and liver metastasis in response to LPS. Material and Methods: Balb/C mice underwent an intra-splenic injection of 2x105 pre-treated murine colon cancer CT-26 cells. There were four groups of pre-treated cells -untreated, LPS, LPS + DPI(Nox inhibitor), LPS + DMSO (n=8/ group). Metastatic burden in the liver was assessed by counting surface liver nodules and liver/body weight ratio at day 7 post injection. Mitotic index was assessed using hematoxylin and eosin histology. Metastatic colonisation was assessed in vitro using SW480 cells in migration and invasion assays. ROS characterisation was examined using intracellular probes. Result: LPS treated cells had enhanced liver metastatic burden compared to untreated cells (p=0.036). DPI successfully attenuated metastatic tumour growth compared to untreated and LPS treated groups (p<0.001). Nox inhibition successfully reduced proliferation in vivo (p=0.002) and, migration (p=0.027), invasion (p=0.041) and epithelial-mesenchymal transition in vitro. Using multiphoton microscopy, endoplasmic reticulum was the intracellular organelle responsible for Nox-generated ROS in response to LPS. Characterisation of the Nox-generated ROS identified H2O2 as the species responsible for facilitating spontaneous and accelerated tumour growth. Conclusion: Targeting Nox generated H2O2 significantly attenuates spontaneous and accelerated metastatic tumour growth. Background: Ischaemia and reperfusion (I/R) elicit an acute inflammatory response characterized by the recruitment of inflammatory cells, oxidative stress and endothelial barrier failure that can lead to interstitial oedema and impairment of organ function. Neutrophils are known to mediate the organ injury, but the precise mechanisms leading to lung neutrophil recruitment are undefined. Monocyte chemoattractant protein 1 (MCP1) and macrophage inflammatory protein 2 (MIP2) are chemotactic for neutrophils in vitro and have been reported to be involved in neutrophil-dependent inflammatory tissue injury. The aim of the present study was to determine the roles of MCP1 and MIP2 in the local tissue injury induced by lung I/R. Material and Methods: Ten large-white pigs were submitted to a left lung auto-transplant. All animals received the same anaesthetic procedure. In order to measure MCP1 and MIP2 tissue levels, lung tissue samples were taken in 4 different moments: 5 min before pneumonectomy; 5 min before reperfusion; 30 min and 60 min after reperfusion. Additionally, myeloperoxidase (MPO) content and lung oedema were also measured. Result: Lung I/R caused substantial pulmonary damage determined as lung oedema. This oedema was accompanied by increased neutrophil accumulation (as measured by tissue MPO content, p<0.05). After 30 min of reperfusion, both MCP1 and MIP2 levels were significantly increased compared to prepneumonectomy levels (p<0.05) and a further increase was observed after 60 min reperfusion (p<0.05). Conclusion: These results suggest that the local expression of MCP1 and MIP2 may be involved in neutrophil-dependent lung injury induced by I/R. Background: Small-bowel is one of the most sensitive organ to ischemia-reperfusion injury, which is a significant problem during transplantation. Pituitary adenylate cyclase-activating polypeptide (PACAP) has cytoprotective effect in ischemic injuries of various tissues. The aim of our study was to measure oxidative stress markers, histological damages and changes of PACAP-38 immunoreactivities and cytokine levels in intestinal grafts stored PACAP-38 containing preservation solution. Material and Methods: Intestinal autotransplantation was performed on male Wistar rats (n=35). Grafts were stored in University of Wisconsin (UW) solution at 4°C for 1 hour (GI), for 3 hours (GII), and for 6 hours (GIII); and in PACAP-38 containing UW solution for 1 hour (GIV), for 3 hours (GV), and for 6 hours (GVI). After preservation reperfusion lasted 3 hours in each group. Tissue oxidative stress parameters (malondialdehide, reduced glutatione, superoxide dismutase), intestinal PACAP-38 immunoreactivities, and cytokine array were measured. Result: Tissue oxidative injury and histological destruction were significantly lower in GIV-GIV compared to GI-GIII. Levels of PACAP-38 immunoreactivity decreased in GI-GII. This decrease was significant following 6 hours cold storage (p<0.05). Values remained significantly higher in grafts stored in PACAP-38 containing UW. Cytokine array revealed that expression of sICAM-1, L-selectin, and the tissue inhibitor of metalloproteinase-1 were increased in GIII, and strong reduction of their activation were observated in GVI. Conclusion: Present study showed that PACAP-38 adding to the conventional UW preservation solution decreased intestinal oxidative injury and structural damages, and mitigated tissue cytokine expression. Background: Multimeric von-Willebrand factor is a wellknown central player not only in physiological hemostasis but in pathological intravascular coagulation. Recently, much attention has been paid to its counteracting partner, AD-AMTS13, as a Savior in various coagulation disorders, including thrombotic microangiopathy. Here we report the impact of ADAMTS13 on hepatic ischemia/reperfusion injury (IRI). Material and Methods: Male wild type (WT) mice and ADAMTS13 knockout (KO) mice (8-10 weeks-old, 129/+Ter/ SvJcl-TgH NCVC) were used. First, they were exposed to 70% partial hepatic ischemia for 60 minutes followed by either vehicle (Group-A: WT + vehicle and Group-B: KO + vehicle) or recombinant ADAMTS13 administration into KO mice intravenously (Group-C: KO + rADAMTS13). Hepatic microcirculation, measured by laser Doppler flowmetry, platelet count, serum transaminase release, liver histology and inflammatory cytokines were also examined. Result: At 24 hours after reperfusion, hepatic microcirculation in Group-B fell down to 33.1% of the pre-ischemic value, which was lower than in Group-A (69.8%, p<0.01). In Group-C, however, it was improved up to 67.4% (p<0.01). Immunohistochemistry with CD42b antibody revealed platelet aggregation in sinusoid in Group-B, which was improved by rADAMTS13 supplementation. In line, platelet counts (45.2 vs. 7.7 vs. 37.8 x105; p<0.05), ALT (5500 vs. 13964 vs. 8417; p<0.05) were all deteriorated in KO, but ameliorated by rAD-AMTS13 administration. Conclusion: ADAMTS13 plays a considerable role in maintaining hepatic microcirculation, and its recombinant agent might be a novel therapeutic approach against hepatic IRI. Background: Acute peritonitis is a serious complication of abdominal surgeries. Left untreated, the inflammatory process is accompanied by disturbances in oxygen dynamics and may lead to septic reactions. We hypothesized that complement system activation and C5a generation is involved in the development of sepsis-induced cellular hypoxia. Therefore, we investigated the effects of C5a antagonist (C5aA) treatment on the alterations of peripheral microcirculation, oxygen consumption (VO2) and delivery (DO2) in a large animal model of intraabdominal sepsis. Material and Methods: Anesthetized minipigs were subjected to fecal peritonitis (0.7 g/kg autofaeces i.p.) without (n=7) or with C5aA treatment (4 mg/kg AcPepA, Nagoya, Japan, n=6) 19 hr after the insult. Invasive hemodynamic monitoring and blood gas analyses were started, VO2-DO2 values were calculated, and sublingual microcirculation parameters (the rate of perfused capillaries, by intravital orthogonal polarization spectral imaging technique) were recorded between the 16-24 hr of sepsis. Result: In septic animals the DO2 (3680±310 ml/min/ m2) and VO2 (510±85 ml/min/m2) values were elevated, while the oxygen extraction ratio (VO2-DO2 ratio <13%) was deteriorated significantly. These changes were accompanied by sublingual microcirculatory deficit, as compared with baseline. The C5aA treatment increased significantly the DO2 and VO2 values, the VO2-DO2 ratio (to 22%) and the perfusion rate of sublingual microcirculation. Conclusion: These data demonstrate that inhibition of complement cascade components has beneficial effects on the oxygen extraction in experimental sepsis and suggest that the C5aA treatment could be a novel therapeutic opportunity to ameliorate the hypoxic consequences of septic inflammation.
doi:10.1159/000363269 pmid:24854186 fatcat:ofafa5cf4vhknamsraqekjznpy