raffinose has been researched along with Disease-Models--Animal* in 39 studies
39 other study(ies) available for raffinose and Disease-Models--Animal
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Effects of Oxygen During Long-term Hypothermic Machine Perfusion in a Porcine Model of Kidney Donation After Circulatory Death.
Hypothermic machine perfusion (HMP) has become standard care in many center's to preserve kidneys donated after circulatory death (DCD). Despite a significant reduction in metabolism at low temperatures, the remaining cellular activity requires oxygen. Because of the role and safety of oxygen during HMP has not been fully clarified, its supply during HMP is not standard yet. This study investigates the effect of administering oxygen during HMP on renal function in a porcine DCD model.. After 30 minutes of warm ischemia, porcine slaughterhouse kidneys were preserved for 24 hours by means of cold storage (CS), or HMP with Belzer Machine Perfusion Solution supplemented with no oxygen, 21% or 100% oxygen. Next, kidneys were reperfused for 4 hours in a normothermic machine perfusion setup.. HMP resulted in significantly better kidney function during normothermic machine perfusion. Thiobarbituric acid-reactive substances, markers of oxidative stress, were significantly lower in HMP preserved kidneys. HMP preserved kidneys showed significantly lower aspartate aminotransferase and lactate dehydrogenase levels compared with kidneys preserved by CS. No differences were found between the HMP groups subjected to different oxygen concentrations. Adenosine triphosphate levels significantly improved during HMP when active oxygenation was applied.. This study showed that preservation of DCD kidneys with HMP is superior to CS. Although the addition of oxygen to HMP did not result in significantly improved renal function, beneficial effects were found in terms of reduced oxidative stress and energy status. Oxygen addition proofed to be safe and did not show detrimental effects. Topics: Adenosine; Allografts; Allopurinol; Animals; Biopsy; Disease Models, Animal; Glutathione; Humans; Hypothermia, Induced; Insulin; Kidney; Organ Preservation; Organ Preservation Solutions; Oxidative Stress; Oxygen; Perfusion; Raffinose; Reperfusion; Reperfusion Injury; Swine; Tissue and Organ Harvesting; Warm Ischemia | 2019 |
Heterologous Antibodies Adsorption in Xenotransplantation of a Landrace Piglet Kidney Into a Rhesus Monkey.
To explore the adsorption of heterologous antibodies in 6 xenotransplants of Landrace piglet kidneys into rhesus monkeys.. The Landrace piglets and rhesus monkeys were used as donors and recipients, respectively. The donor kidney was the left kidney excised from each Landrace piglet and lavaged with University of Wisconsin solution through the renal artery and vein ex vivo. The renal arteriovenous end of the recipient was preserved. After anastomosis of the renal artery and vein with the arteriovenous end of the recipient for reperfusion, a cross-lymphocyte cytotoxicity test of the heterogeneous kidney was performed.. All 6 Landrace piglet kidneys absorbed heterologous antibodies that were pre-existing in the rhesus macaques' kidneys. The cross-lymphocyte toxicity test was performed after the kidney were completely blackened. The cross-lymphocyte toxicity in all each heterogeneous kidney changed from strong positive to weak positive.. Heterologous antibodies were adsorbed in xenotransplants of Landrace piglet kidneys into rhesus monkeys. Xenotransplanted kidney can adsorb heterologous antibodies and consume relevant complements, which is a good model for research of hyperacute rejection in xenotransplantation. Topics: Adenosine; Adsorption; Allopurinol; Animals; Antibodies, Heterophile; Disease Models, Animal; Female; Glutathione; Graft Rejection; Insulin; Kidney; Kidney Transplantation; Macaca mulatta; Organ Preservation Solutions; Raffinose; Swine; Tissue Donors; Transplantation, Heterologous | 2019 |
The Optimal PEG for Kidney Preservation: A Preclinical Porcine Study.
University of Wisconsin (UW) solution is not optimal for preservation of marginal organs. Polyethylene glycol (PEG) could improve protection. Similarly formulated solutions containing either 15 or 20 g/L PEG 20 kDa or 5, 15 and 30 g/L PEG 35 kDa were tested in vitro on kidney endothelial cells, ex vivo on preserved kidneys, and in vivo in a pig kidney autograft model. In vitro, all PEGs provided superior preservation than UW in terms of cell survival, adenosine triphosphate (ATP) production, and activation of survival pathways. Ex vivo, tissue injury was lower with PEG 20 kDa compared to UW or PEG 35 kDa. In vivo, function recovery was identical between UW and PEG 35 kDa groups, while PEG 20 kDa displayed swifter recovery. At three months, PEG 35 kDa 15 and 30 g/L animals had worse outcomes than UW, while 5 g/L PEG 35 kDa was similar. PEG 20 kDa was superior to both UW and PEG 35 kDa in terms of function and fibrosis development, with low activation of damage pathways. PEG 20 kDa at 15 g/L was superior to 20 g/L. While in vitro models did not discriminate between PEGs, in large animal models of transplantation we showed that PEG 20 kDa offers a higher level of protection than UW and that longer chains such as PEG 35 kDa must be used at low doses, such as found in Institut George Lopez (IGL1, 1g/L). Topics: Adenosine; Adenosine Triphosphate; Allopurinol; Animals; Cell Hypoxia; Disease Models, Animal; Endothelial Cells; Glutathione; Insulin; Kidney; Kidney Function Tests; Kidney Transplantation; Male; Molecular Weight; Organ Preservation; Organ Preservation Solutions; Polyethylene Glycols; Primary Cell Culture; Raffinose; Recovery of Function; Reperfusion Injury; Swine; Transplantation, Autologous | 2018 |
Cardiotrophin-1 Improves Kidney Preservation, Graft Function, and Survival in Transplanted Rats.
Cold ischemia-reperfusion injury is unavoidable during organ transplantation, and prolonged preservation is associated with poorer function recovery. Cardiotrophin-1 (CT-1) is an IL-6 family cytokine with cytoprotective properties. This preclinical study in rats tested whether CT-1 mitigates cold renal ischemia-reperfusion injury in the context of the transplantation of long-time preserved kidneys.. Kidneys were flushed with cold (4°C) University of Wisconsin solution containing 0.2 μg/mL CT-1 and stored for several periods of time at 4°C in the same solution. In a second approach, kidneys were first cold-preserved for 6 hours and then were perfused with University of Wisconsin solution containing CT-1 (0, 16, 32, or 64 μg/mL) and further cold-preserved. Organ damage markers were measured in the kidneys at the end of the storage period. For renal transplantation, recipient consanguineous Fischer rats underwent bilateral nephrectomy and received a previously cold-preserved (24 hours) kidney as described above. Survival and creatinine clearance were monitored over 30 days.. Cardiotrophin-1 in perfusion and preservation fluids reduced oxidative stress markers (superoxide anion and inducible nitric oxide synthase), inflammation markers (NF-κB and tumor necrosis factor-α), and vascular damage (vascular cell adhesion molecule-1) and activated leukemia inhibitory factor receptor and STAT-3 survival signaling. Transplantation of kidneys cold-preserved with CT-1 increased rat survival and renal function (ie, lower plasma creatinine and higher creatinine clearance) and improved kidney damage markers after transplantation (ie, lower superoxide anion, tumor necrosis factor-α, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 and higher NF-κB).. Cardiotrophin-1 represents a novel therapeutic strategy to reduce ischemia-reperfusion and cold preservation injury to rescue suboptimal kidneys and, consequently, to improve the clinical outcomes of renal transplantation. Topics: Adenosine; Allografts; Allopurinol; Animals; Cold Ischemia; Cytokines; Disease Models, Animal; Glutathione; Graft Survival; Humans; Insulin; Kidney; Kidney Function Tests; Kidney Transplantation; Male; Nephrectomy; Organ Preservation; Organ Preservation Solutions; Perfusion; Raffinose; Rats; Rats, Inbred F344; Reperfusion Injury; Tissue and Organ Harvesting | 2018 |
Intra Amniotic Administration of Raffinose and Stachyose Affects the Intestinal Brush Border Functionality and Alters Gut Microflora Populations.
This study investigates the effectiveness of two types of prebiotics-stachyose and raffinose-which are present in staple food crops that are widely consumed in regions where dietary Fe deficiency is a health concern. The hypothesis is that these prebiotics will improve Fe status, intestinal functionality, and increase health-promoting bacterial populations in vivo ( Topics: Animals; Bifidobacterium; Biological Availability; Chickens; Clostridium; Disease Models, Animal; Escherichia coli; Ferritins; Gastrointestinal Microbiome; Intestinal Mucosa; Intestines; Iron; Lactobacillus; Liver; Microvilli; Oligosaccharides; Prebiotics; Probiotics; Raffinose | 2017 |
Liver graft preservation using perfluorocarbon improves the outcomes of simulated donation after cardiac death liver transplantation in rats.
The outcomes of liver transplantation (LT) from donation after cardiac death (DCD) donors remain poor due to severe warm ischemia injury. Perfluorocarbon (PFC) is a novel compound with high oxygen carrying capacity. In the present study, a rat model simulating DCD LT was used, and the impact of improved graft oxygenation provided by PFC addition on liver ischemia/reperfusion injury (IRI) and survival after DCD LT was investigated. Orthotopic liver transplants were performed in male Lewis rats, using DCD liver grafts preserved with cold University of Wisconsin (UW) solution in the control group and preserved with cold oxygenated UW solution with addition of 20% PFC in the PFC group. For experiment I, in a 30-minute donor warm ischemia model, postoperative graft injury was analyzed at 3 and 6 hours after transplantation. For experiment II, in a 50-minute donor warm ischemia model, the postoperative survival was assessed. For experiment I, the levels of serum aspartate aminotransferase, alanine aminotransferase, hyaluronic acid, malondialdehyde, and several inflammatory cytokines were significantly lower in the PFC group. The hepatic expression levels of tumor necrosis factor α and interleukin 6 were significantly lower, and the expression level of heme oxygenase 1 was significantly higher in the PFC group. Histological analysis showed significantly less necrosis and apoptosis in the PFC group. Sinusoidal endothelial cells and microvilli of the bile canaliculi were well preserved in the PFC group. For experiment II, the postoperative survival rate was significantly improved in the PFC group. In conclusion, graft preservation with PFC attenuated liver IRI and improved postoperative survival. This graft preservation protocol might be a new therapeutic option to improve the outcomes of DCD LT. Liver Transplantation 23 1171-1185 2017 AASLD. Topics: Adenosine; Allografts; Allopurinol; Animals; Disease Models, Animal; Fluorocarbons; Glutathione; Graft Survival; Humans; Insulin; Liver; Liver Function Tests; Liver Transplantation; Male; Organ Preservation; Organ Preservation Solutions; Perfusion; Postoperative Period; Raffinose; Rats; Rats, Inbred Lew; Reperfusion Injury; Survival Rate; Time Factors; Treatment Outcome; Warm Ischemia | 2017 |
Evaluation of silybum marinaum efficacy on University of Wisconsin and histidine-tryptophan-ketoglutarate solutions latter the damage of the perfused liver.
To investigate the hepatoprotective and antioxidant effeicacies of Silybum marianum's (silymarin, S) on University of Wisconsin (UW) and histidinetryptophan-ketoglutarate (HTK) preservation solutions.. Thirty two Wistar albino adult male rats were used. Group 1: UW group, Group 2: UW + Silymarin group(S), Group 3: HTK group, Group 4: HTK + silymarin group (S), respectively. Silymarin was enforced intraperitoneally before the surgery. Biopsies were enforced in 0, 6 and 12.hours to investigate.. Biochemical parameters examined in alanine aminotransferase (ALT), furthermore superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA) in rats were also evaluated. Detected histopathological changings were substantially declining in the groups that received silymarin, cellular damage was decreased significantly in HTK + Silymarin group, according to other groups. It has been identified as the most effective group was HTK + silymarin group in evaluation of ALT, electron microscopic results, also decreased MDA and elevated in SOD, and CAT activity. Caspase 3 analysis showed a substantial lower apoptosis ratio in the silymarin groups than in the non-performed groups (p<0.05).. Histidinetryptophan-ketoglutarate+silymarin group provides better hepatoprotection than other groups, by decreasing the hepatic pathologic damage, delayed changes that arise under cold ischemic terms. Topics: Adenosine; Allopurinol; Animals; Antioxidants; Chemical and Drug Induced Liver Injury; Disease Models, Animal; Glucose; Glutathione; Immunohistochemistry; Insulin; Male; Mannitol; Organ Preservation Solutions; Potassium Chloride; Procaine; Protective Agents; Raffinose; Rats; Rats, Wistar; Silymarin | 2017 |
Influence of a modified preservation solution in kidney transplantation: A comparative experimental study in a porcine model.
Currently, due to lack of optimal donors, more marginal organs are transplanted. Therefore, there is a high interest to ameliorate preischemic organ preservation, especially for critical donor organs. In this regard, a new histidine-tryptophane ketoglutarate (HTK-N) solution has been designed and its protective efficacy was compared with the standard preservation solutions-University of Wisconsin solution and standard HTK or Custodiol (Bretschneider's solution).. Seventy-two landrace pigs were included into the study, as donors and recipients. The donor kidneys were perfused during explantation with cold University of Wisconsin solution (n = 12), standard HTK (n = 12), or HTK-N solutions (n = 12), kept in the respective preservation solution at 4°C for 30 hours, implanted in the recipient pigs, and reperfused. The pigs survived in daily control for 7 days. The serum creatinine and blood urea nitrogen were assessed in pre- and postreperfusion phase on the 3. The three preservation groups were comparable in age, body weight, and hemodynamic parameters. According to statistical proof, they differed in none of the control parameters.. Although the new preservation HTK solution is in several points a well-thought-out modification of the standard HTK solution, its preservation efficacy, at least for kidney preservation in a pig model for 30 hours, seems to be comparable to the current used solutions. A real advantage, however, could be confirmed in clinical settings, where marginal organs may influence the clinical outcome. Topics: Adenosine; Allopurinol; Animals; Biopsy, Needle; Disease Models, Animal; Female; Glucose; Glutathione; Graft Rejection; Graft Survival; Immunohistochemistry; Insulin; Kidney Transplantation; Male; Mannitol; Organ Preservation; Organ Preservation Solutions; Potassium Chloride; Procaine; Raffinose; Random Allocation; Sensitivity and Specificity; Survival Rate; Swine; Treatment Outcome | 2017 |
Celsior preserves cardiac mechano-energetics better than University of Wisconsin solution by preventing oxidative stress.
Identity of the optimal heart preservation solution remains unknown. Because oxidative stress contributes to contractile failure in the ischaemic/reperfused myocardium and the main characteristic of Celsior is its antioxidant effect, it is important to elucidate the relationship between the inhibitory effect on oxidative stress and cardiac mechano-energetics. We therefore evaluated the efficacy of Celsior from both aspects by comparison with the University of Wisconsin solution (UWS).. We used 18 excised cross-circulated canine hearts. Excised hearts were preserved with UWS (n = 6) or Celsior (n = 6) for 3 h at 4 °C; the remaining six served as controls. Hearts were then cross-circulated and rewarmed. The end-systolic pressure-volume ratio (LV Emax) and the ventricular pressure-volume area, which is a measure of total mechanical energy, were assessed after reperfusion. Biopsies were taken from the endocardium after excising the heart, before reperfusion, after reperfusion and 4 h after reperfusion to assess the inhibitory effect of each agent on oxidative stress. Endo-myocardial biopsy samples were studied immunohistochemically for expression of 4-hydroxy-2-nonenal (HNE)-modified protein, which is a major lipid peroxidation product.. Emax in the UWS group was significantly smaller than in the control group, whereas the Emax in the Celsior group was preserved. Oxygen cost of Emax in the UWS group was significantly higher than in the Celsior group. Myocardial HNE-modified protein levels increased gradually, both under preservation and after reperfusion in the UWS group. Myocardial HNE-modified protein levels in the Celsior group were lower, mainly before and 4 h after reperfusion compared with the UWS group.. Celsior may maintain cardiac contractility and conserve oxygen cost by inhibiting oxidative stress. Topics: Adenosine; Allopurinol; Animals; Disaccharides; Disease Models, Animal; Dogs; Electrolytes; Glutamates; Glutathione; Heart; Heart Transplantation; Histidine; Insulin; Mannitol; Myocardial Contraction; Myocardial Reperfusion Injury; Myocardium; Organ Preservation Solutions; Oxidative Stress; Raffinose; Tissue Preservation | 2016 |
Recipient T cell TIM-3 and hepatocyte galectin-9 signalling protects mouse liver transplants against ischemia-reperfusion injury.
By binding to T cell immunoglobulin mucin-3 (TIM-3) on activated Th1 cells, galectin-9 (Gal-9) negatively regulates Th1-type alloimmunity. Although T cells contribute to hepatic ischemia-reperfusion injury (IRI), it is unknown whether negative T cell-dependent TIM-3 co-stimulation may rescue IR-stressed orthotopic liver transplants from innate immunity-driven inflammation.. We used wild type (WT) and TIM-3 transgenic (Tg) mice (C57BL/6) as liver donors and recipients in a clinically-relevant model of hepatic cold storage (20 h at 4°C in UW solution) and syngeneic orthotopic liver transplantation (OLT).. Orthotopic liver transplants in WT or TIM-3Tg→TIM-3Tg groups were resistant against IR-stress, evidenced by preserved hepatocellular function (serum ALT levels) and liver architecture (Suzuki's score). In contrast, orthotopic liver transplants in WT or TIM-3Tg→WT groups were susceptible to IRI. TIM-3 induction in circulating CD4+ T cells of the recipient: (1) depressed T-bet/IFN-γ, while amplifying GATA3 and IL-4/IL-10 expression in orthotopic liver transplants; (2) promoted T cell exhaustion (PD-1, LAG-3) phenotype; and (3) depressed neutrophil and macrophage infiltration/function in orthotopic liver transplants. In parallel studies, we documented for the first time that Gal-9, a natural TIM-3 ligand, was produced primarily by and released from IR-stressed hepatocytes, both in vivo and in vitro. Moreover, exogenous recombinant Gal-9 (rGal-9) potentiated liver resistance against IRI by depressing T cell activation and promoting apoptosis of CD4+ T cells.. Harnessing TIM-3/Gal-9 signalling at the T cell-hepatocyte interface facilitates homeostasis in IR-stressed orthotopic liver transplants. Enhancing anti-oxidant hepatocyte Gal-9 potentiates liver IR-resistance. Negative regulation by recipient TIM-3+CD4+ cells provides evidence for cytoprotective functions of a discrete T cell subset, which should be spared when applying T cell-targeted immunosuppression in transplant recipients. Topics: Adenosine; Allopurinol; Animals; Apoptosis; Cell Differentiation; Disease Models, Animal; Galectins; Glutathione; Hepatitis A Virus Cellular Receptor 2; Hepatocytes; Immunity, Innate; In Vitro Techniques; Insulin; Liver Transplantation; Lymphocyte Activation; Macrophages; Male; Mice; Mice, 129 Strain; Mice, Inbred C57BL; Mice, Knockout; Mice, Transgenic; Neutrophils; Organ Preservation; Organ Preservation Solutions; Raffinose; Receptors, Virus; Reperfusion Injury; Signal Transduction; T-Lymphocytes | 2015 |
A Yeast/Drosophila Screen to Identify New Compounds Overcoming Frataxin Deficiency.
Friedreich's ataxia (FA) is a rare neurodegenerative disease which is very debilitating for the patients who progressively lose their autonomy. The lack of efficient therapeutic treatment of the disease strongly argues for urgent need to search for new active compounds that may stop the progression of the disease or prevent the appearance of the symptoms when the genetic defect is diagnosed early enough. In the present study, we used a yeast strain with a deletion of the frataxin homologue gene as a model of FA cells in a primary screen of two chemical libraries, a fraction of the French National Chemical Library (5500 compounds) and the Prestwick collection (880 compounds). We ran a secondary screen on Drosophila melanogaster flies expressing reduced levels of frataxin during larval development. Half of the compounds selected in yeast appeared to be active in flies in this developmental paradigm, and one of the two compounds with highest activities in this assay partially rescued the heart dilatation phenotype resulting from heart specific depletion of frataxin. The unique complementarity of these two frataxin-deficient models, unicellular and multicellular, appears to be very efficient to select new compounds with improved selectivity, bringing significant perspectives towards improvements in FA therapy. Topics: Animals; Cell Proliferation; Disease Models, Animal; Drosophila; Drosophila Proteins; Frataxin; Heart; Iron-Binding Proteins; Larva; Microscopy, Video; Raffinose; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins; Small Molecule Libraries | 2015 |
Cyclodextrin curcumin formulation improves outcome in a preclinical pig model of marginal kidney transplantation.
Decreasing organ quality is prompting research toward new methods to alleviate ischemia reperfusion injury (IRI). Oxidative stress and nuclear factor kappa beta (NF-κB) activation are well-described elements of IRI. We added cyclodextrin-complexed curcumin (CDC), a potent antioxidant and NF-κB inhibitor, to University of Wisconsin (UW) solution (Belzer's Solution, Viaspan), one of the most effective clinically approved preservative solutions. The effects of CDC were evaluated on pig endothelial cells and in an autologous donation after circulatory death (DCD) kidney transplantation model in large white pigs. CDC allowed rapid and lasting uptake of curcumin into cells. In vitro, CDC decreased mitochondrial loss of function, improved viability and lowered endothelial activation. In vivo, CDC improved function recovery, lowered histological injury and doubled animal survival (83.3% vs. 41.7%). At 3 months, immunohistochemical staining for epithelial-to-mesenchymal transition (EMT) and fibrosis markers was intense in UW grafts while it remained limited in the UW + CDC group. Transcriptional analysis showed that CDC treatment protected against up-regulation of several pathophysiological pathways leading to inflammation, EMT and fibrosis. Thus, use of CDC in a preclinical transplantation model with stringent IRI rescued kidney grafts from an unfavorable prognosis. As curcumin has proved well tolerated and nontoxic, this strategy shows promise for translation to the clinic. Topics: Adenosine; Allopurinol; Animals; Anti-Inflammatory Agents, Non-Steroidal; Blotting, Western; Cells, Cultured; Chemistry, Pharmaceutical; Curcumin; Cyclodextrins; Disease Models, Animal; Fibrosis; Flow Cytometry; Glutathione; Graft Rejection; Humans; Inflammation; Insulin; Kidney Transplantation; Kidney Tubules; Male; Organ Preservation Solutions; Oxidative Stress; Prostate; Raffinose; Real-Time Polymerase Chain Reaction; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Swine | 2014 |
Iron-induced oxidative rat liver injury after non-heart-beating warm ischemia is mediated by tumor necrosis factor α and prevented by deferoxamine.
This study investigated iron-induced injury after warm ischemia in a non-heart-beating (NHB) rat liver model and the effects of deferoxamine (DFO). Livers from heart-beating (HB) rats or rats that were NHB for 60 minutes were stored in University of Wisconsin solution for 5 hours at 4°C [cold storage (CS)] and then were subjected to 2 hours of machine reperfusion (MRP) at 37°C. Three NHB groups were compared: (1) no DFO, (2) DFO 30 minutes before cardiac arrest and during CS and MRP, and (3) DFO during CS and MRP. Aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) levels in the NHB perfusate were significantly elevated (P < 0.01) in comparison with levels in HB controls after CS and MRP. After CS, the levels of iron and tumor necrosis factor α (TNF-α) were 0.077 ± 0.007 μmol/g and 151 ± 26 pg/g, respectively, in the NHB group and 0.022 ± 0.004 μmol/g and 17 ± 7 pg/g, respectively, in the HB group (P < 0.01). After MRP, LDH significantly correlated with iron (R(2) = 0.81, P < 0.01). The DFO pretreatment of NHB donors decreased AST (7.3 ± 0.8 versus 4.0 ± 0.5 U/g of liver, P < 0.05) and LDH (42.5 ± 4.1 versus 20.4 ± 2.5 U/g of liver, P < 0.05) with 2 hours of MRP and increased bile flow during MRP (142 ± 34 versus 240 ± 18 μL/g, P < 0.05). It also reduced the levels of iron (0.077 ± 0.007 versus 0.050 ± 0.008 μmol/g, P < 0.05) and TNF-α (151 ± 26 versus 51 ± 13 pg/g, P < 0.05) after CS and the levels of lipid peroxidation products F2-isoprostane (149 ± 11 versus 99 ± 10 ng/g, P < 0.05) and malondialdehyde (1.58 ± 0.1 versus 1.14 ± 0.08 μmol/g, P < 0.05) after MRP. In conclusion, iron-initiated oxidative stress is likely involved in NHB donor liver injury, and importantly, DFO pretreatment reduces liver damage. Topics: Adenosine; Allopurinol; Animals; Aspartate Aminotransferases; Bile; Deferoxamine; Disease Models, Animal; F2-Isoprostanes; Glutathione; Heart Arrest; Insulin; Iron; L-Lactate Dehydrogenase; Liver; Liver Diseases; Male; Malondialdehyde; Organ Preservation Solutions; Oxidative Stress; Perfusion; Raffinose; Rats; Tumor Necrosis Factor-alpha; Warm Ischemia | 2014 |
Rewarming preservation by organ perfusion system for donation after cardiac death liver grafts in pigs.
Use of grafts from donors after cardiac death (DCD) would greatly contribute to the expansion of the donor organ pool. However, this requires the development of novel preservation methods to recover the organ from changes due to warm ischemia time (WIT).. Porcine livers were perfused with a newly developed machine perfusion (MP) system. The livers were perfused with modified University of Wisconsin solution (UW) - gluconate. All grafts were procured after acute hemorrhagic shock with the ventilator off. For group 1 (n = 6), grafts were procured after WIT of 60 minutes and preserved by hypothermic MP (HMP) for 3 hours. For group 2 (n = 5), grafts were preserved with 2 hours of simple cold storage (SCS) and HMP for 2 hours. For group 3 (n = 6), grafts were preserved with 2 hours of SCS and rewarming up to 25°C by MP for 2 hours (RMP). The preserved liver grafts were transplanted orthotopically.. The alanine aminotransferase level in perfusate in RMP during perfusion preservation was maintained at less than that of HMP. The levels of aspartate aminotransferase and lactate dehydrogenase in the 2 hours after reperfusion were significantly lower in group 3. Histologically, the necrosis of hepatocytes was less severe in group 3. The survival rate in group 3 was 2/4, but 0/4 in the other group.. RMP is expected to facilitate the recovery of the DCD liver grafts. Topics: Adenosine; Alanine Transaminase; Allopurinol; Animals; Aspartate Aminotransferases; Biomarkers; Cold Ischemia; Disease Models, Animal; Female; Glutathione; Graft Survival; Heart Arrest; Hepatectomy; Insulin; L-Lactate Dehydrogenase; Liver; Liver Transplantation; Necrosis; Organ Preservation; Organ Preservation Solutions; Perfusion; Raffinose; Reperfusion Injury; Rewarming; Sus scrofa; Time Factors; Tissue and Organ Harvesting; Warm Ischemia | 2014 |
Polyethylene glycol rinse solution: an effective way to prevent ischemia-reperfusion injury.
To test whether a new rinse solution containing polyethylene glycol 35 (PEG-35) could prevent ischemia-reperfusion injury (IRI) in liver grafts.. Sprague-Dawley rat livers were stored in University of Wisconsin preservation solution and then washed with different rinse solutions (Ringer's lactate solution and a new rinse solution enriched with PEG-35 at either 1 or 5 g/L) before ex vivo perfusion with Krebs-Heinseleit buffer solution. We assessed the following: liver injury (transaminase levels), mitochondrial damage (glutamate dehydrogenase activity), liver function (bile output and vascular resistance), oxidative stress (malondialdehyde), nitric oxide, liver autophagy (Beclin-1 and LCB3) and cytoskeleton integrity (filament and globular actin fraction); as well as levels of metalloproteinases (MMP2 and MMP9), adenosine monophosphate-activated protein kinase (AMPK), heat shock protein 70 (HSP70) and heme oxygenase 1 (HO-1).. When we used the PEG-35 rinse solution, reduced hepatic injury and improved liver function were noted after reperfusion. The PEG-35 rinse solution prevented oxidative stress, mitochondrial damage, and liver autophagy. Further, it increased the expression of cytoprotective heat shock proteins such as HO-1 and HSP70, activated AMPK, and contributed to the restoration of cytoskeleton integrity after IRI.. Using the rinse solution containing PEG-35 was effective for decreasing liver graft vulnerability to IRI. Topics: Adenosine; Allopurinol; Animals; Autophagy; Biomarkers; Cold Ischemia; Cytoprotection; Cytoskeleton; Disease Models, Animal; Glutathione; Hepatectomy; Insulin; Liver; Liver Function Tests; Male; Mitochondria, Liver; Organ Preservation; Organ Preservation Solutions; Oxidative Stress; Polyethylene Glycols; Raffinose; Rats, Sprague-Dawley; Reperfusion Injury; Signal Transduction; Time Factors | 2014 |
Dopamine treatment of brain-dead Fisher rats improves renal histology but not early renal function in Lewis recipients after prolonged static cold storage.
Brain death (BD) and cold preservation are major risk factors for an unfavorable transplantation outcome. Although donor dopamine treatment in brain-dead rats improves renal function and histology in allogeneic recipients, it remains to be assessed if this also holds true for the combinations of BD and prolonged static cold preservation.. BD was induced in F344 donor rats, which were subsequently treated with NaCl 1 mL/h (BD, n = 11), NaCl/hydroxy ethyl starch (BD-norm, n = 10), or 10 μg/min/kg dopamine (BD-dopa, n = 10). Renal grafts were harvested 4 h after BD and transplanted into bilateral nephrectomized Lewis recipients 6 h after cold preservation in University of Wisconsin solution. Renal function was evaluated by use of serum creatinine and urea concentrations at days 0, 1, 3, 5, and 10. Ten days after transplantation, recipients were killed and the renal allografts were processed for light microscopy and immune histology.. Serum urea concentrations at days 5 and 10 were significantly lower in recipients that received a renal graft from dopamine-treated rats; for serum creatinine, only a trend was observed at day 10. Immune histology revealed a lower degree of ED1-positive cells in the donor dopamine-treated group. Under light microscopy, Banff classification revealed significantly less intimal arteritis in these grafts (P < .05).. Although donor dopamine treatment clearly improves renal histology in this model, the beneficial effect on early renal function was marginal. It remains to be assessed if donor dopamine treatment has a beneficial effect on renal function in long-term follow-up. Topics: Adenosine; Allopurinol; Animals; Brain Death; Cardiotonic Agents; Disease Models, Animal; Dopamine; Follow-Up Studies; Glomerular Filtration Rate; Glutathione; Insulin; Kidney; Kidney Transplantation; Male; Organ Preservation Solutions; Raffinose; Rats; Rats, Inbred F344; Rats, Inbred Lew; Tissue Donors; Transplantation, Homologous | 2014 |
[Effect of ischemic postconditioning on oxidative stress and structural tissue changes in intestinal warm ischemic and autotransplantation models].
Our study investigated the effect of ischemic postconditioning (IPO) in intestinal warm ischemia/reperfusion (I/R) and autotransplantation models.. Warm ischemia was performed by occlusion of superior mesenteric artery for 1, 3 and 6 hours in white domestic pigs (n = 15). Prior to 3 hours reperfusion the intestine was postconditioned by 3 cycles of 30-seconds ischemia and 30-seconds reperfusion (IPO protocol). In the cold ischemia group (n = 15) the bowel was preserved in University of Wisconsin solution for 1, 3, and 6 hours. Prior to 3 hours reperfusion IPO protocol was applied, too. Tissue samples were collected after laparotomy (control) and at the end of the reperfusion periods. As far as oxidative stress markers, malondialdehyde and reduced glutathione (GSH) levels and superoxide dismutase (SOD) activity were determined. Tissue damage was evaluated by qualitative (Park-classification) and quantitative (Scion Image) methods.. As regards oxidative stress parameters, lipidperoxidation decreased and the protective effect of endogenous antioxidants (GSH, SOD) retained significantly by IPO procedure at the end of reperfusion. Tissue injury correlated significantly by the duration of warm ischemia and cold preservation. Quantitative analysis demonstrated that IPO ameliorated tissue injury in each group (p < 0.05).. IPO significantly attenuated intestinal oxidative stress and morphological damages in warm and cold I/R models. Topics: Adenosine; Allopurinol; Animals; Antioxidants; Disease Models, Animal; Glutathione; Insulin; Intestines; Ischemia; Ischemic Postconditioning; Laparotomy; Lipid Peroxidation; Malondialdehyde; Organ Preservation Solutions; Oxidative Stress; Raffinose; Reperfusion Injury; Superoxide Dismutase; Sus scrofa; Time Factors; Transplantation, Autologous; Warm Ischemia | 2011 |
Relationship between ischemia/reperfusion injury and the stimulus of fibrogenesis in an experimental model: comparison among different preservation solutions.
Orthotopic liver transplantation (OLT) has been the standard treatment for end-stage acute and chronic liver disease. Ischemia-reperfusion (I/R) injury is one of the major causes of poor graft function early after OLT, and adversely influencing graft and patient survivals. It is unknown whether I/R injury influences liver fibrogenesis.. Livers from 25 adult male Wistar rats were randomly assigned into 5 experimental groups according to the preservation solution: saline solution (SS); University of Wisconsin (UW) solution; Fructose 1, 6-biphosphate (FBP); S-Nitroso-N-Acetylcysteine (SNAC): or UW+SNAC (SNAC+UW). Aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactic dehydrogenase (LDH) were determined in preservation solution samples at 2, 4, and 6 hours. After 6 hours of cold ischemia, ex situ reperfusion was applied to the liver for 15 minutes. Serum AST, ALT, LDH, and renin levels were determined. Fresh liver slices were processed for histological studies, determination of thiobarbituric acid reactive substances, catalase, and glutathione, and expression of TGF-β1 and angiotensin II AT1 receptor.. AST was significantly lower during cold storage with UW than with the older media (P=.001); ALT was lower in the FBP group (P=.023) and LDH was lower in the FBP and SNAC groups (P=.007). After reperfusion, serum AST, ALT, LDH, and TBARS showed no significant differences among the groups. Catalase was significantly lower in the SS and FBP groups (P=.008 and P=.006, respectively). Compared with UW, glutathione concentrations were significantly higher in SS, FBP, and SNAC 200 (P=.004). Renin levels were significantly lower in the FBP group (P=.022). No histological signs of preservation injury were observed in the hepatic sample. No expressions were detected of TGF-β1 or AT1 receptor.. In this experimental model of early reperfusion injury, preservation changes related to higher levels of renin, which suggest its role in fibrogenesis. FBP was associated with lower renin levels than other solutions including UW. Topics: Acetylcysteine; Adenosine; Alanine Transaminase; Allopurinol; Animals; Aspartate Aminotransferases; Biomarkers; Catalase; Disease Models, Animal; Fructosediphosphates; Glutathione; Insulin; L-Lactate Dehydrogenase; Liver; Liver Cirrhosis; Liver Transplantation; Male; Organ Preservation Solutions; Raffinose; Rats; Rats, Wistar; Receptor, Angiotensin, Type 1; Renin; Reperfusion Injury; Thiobarbituric Acid Reactive Substances; Time Factors; Transforming Growth Factor beta1 | 2011 |
A comparison of hypothermic machine perfusion versus static cold storage in an experimental model of renal ischemia reperfusion injury.
There is increasing support for the use of hypothermic machine perfusion (HMP) in an attempt to reduce preservation injury. However, experimental evidence is needed to further examine the effects of HMP on renal ischemia reperfusion injury.. Porcine kidneys were subjected to 10 min of warm ischemia followed by 18 hr of static cold storage with hyperosomolar citrate (HOC), histidine-tryptophan-ketoglutarate (HTK), or University of Wisconsin (UW) solutions or 18 hr HMP with Kidney Perfusion Solution using the Lifeport perfusion system. Renal function, oxidative damage, and morphology were assessed during 3 hr of reperfusion with autologous blood using an isolated organ perfusion system.. During reperfusion, intrarenal resistance was significantly lower in the HMP group compared with HOC and UW (area under the curve; HMP 3.8+/-1.7, HOC 9.1+/-4.3, UW 7.7+/-2.2, HTK 5.6+/-1.9 mm Hg/min; P=0.006), and creatinine clearance was significantly higher compared with the UW group (area under the curve creatinine clearance; HMP 9.8+/-7.3, HOC 2.2+/-1.7, UW 1.8+/-1.0, HTK 2.1+/-1.8 mL/min/100 g; P=0.004). Tubular function was significantly improved in the HMP group (P<0.05); however, levels of lipid peroxidation were significantly higher (P=0.005).. HMP demonstrated a reduced level of preservation injury compared with the static techniques resulting in improved renal and tubular function and less tubular cell inflammation during reperfusion. Topics: Acid-Base Equilibrium; Adenosine; Allopurinol; Animals; Aspartate Aminotransferases; Biomarkers; Citrates; Cold Ischemia; Creatinine; Disease Models, Animal; Equipment Design; Glucose; Glutathione; Hypothermia, Induced; Insulin; Kidney; Kidney Transplantation; L-Lactate Dehydrogenase; Lipid Peroxidation; Mannitol; Organ Preservation Solutions; Oxidative Stress; Perfusion; Peroxidase; Potassium Chloride; Procaine; Raffinose; Reperfusion Injury; Swine; Time Factors | 2010 |
Improved rat steatotic and nonsteatotic liver preservation by the addition of epidermal growth factor and insulin-like growth factor-I to University of Wisconsin solution.
This study examined the effects of epidermal growth factor (EGF) and insulin-like growth factor-I (IGF-I) supplementation to University of Wisconsin solution (UW) in steatotic and nonsteatotic livers during cold storage. Hepatic injury and function were evaluated in livers preserved for 24 hours at 4 degrees C in UW and in UW with EGF and IGF-I (separately or in combination) and then perfused ex vivo for 2 hours at 37 degrees C. AKT was inhibited pharmacologically. In addition, hepatic injury and survival were evaluated in recipients who underwent transplantation with steatotic and nonsteatotic livers preserved for 6 hours in UW and UW with EGF and IGF-I (separately or in combination). The results, based on isolated perfused liver, indicated that the addition of EGF and IGF-I (separately or in combination) to UW reduced hepatic injury and improved function in both liver types. A combination of EGF and IGF-I resulted in hepatic injury and function parameters in both liver types similar to those obtained by EGF and IGF-I separately. EGF increased IGF-I, and both additives up-regulated AKT in both liver types. This was associated with glycogen synthase kinase-3beta (GSK3(beta)) inhibition in nonsteatotic livers and PPAR gamma overexpression in steatotic livers. When AKT was inhibited, the effects of EGF and IGF-I on GSK3(beta), PPAR gamma, hepatic injury and function disappeared. The benefits of EGF and IGF-I as additives in UW solution were also clearly seen in the liver transplantation model, because the presence of EGF and IGF-I (separately or in combination) in UW solution reduced hepatic injury and improved survival in recipients who underwent transplantation with steatotic and nonsteatotic liver grafts. In conclusion, EGF and IGF-I may constitute new additives to UW solution in steatotic and nonsteatotic liver preservation, whereas a combination of both seems unnecessary. Topics: Adenosine; Allopurinol; Animals; Cell Survival; Cold Ischemia; Disease Models, Animal; Epidermal Growth Factor; Fatty Liver; Glutathione; Glycogen Synthase Kinase 3; Glycogen Synthase Kinase 3 beta; Insulin; Insulin-Like Growth Factor I; Liver; Liver Transplantation; Organ Preservation; Organ Preservation Solutions; Perfusion; PPAR gamma; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-akt; Raffinose; Rats; Rats, Zucker; Recombinant Proteins; Reperfusion Injury; Time Factors | 2010 |
Inhibition of protein kinase C alpha improves myocardial beta-adrenergic receptor signaling and ventricular function in a model of myocardial preservation.
The specific effect of protein kinase C alpha, the primary ventricular calcium-dependent protein kinase C isoform, on myocardial protection is unclear. The objective of this study was to determine the role of protein kinase C alpha in myocardial protection and recovery of function after cardioplegic arrest, cold preservation, and normothermic reperfusion, as relevant to cardiac transplantation.. We used an ex vivo murine model, and hearts were arrested with cold crystalloid cardioplegia or saline as a control and maintained at 4 degrees C for 4 hours. This was followed by normothermic reperfusion for 90 minutes. Transgenic hearts with cardiac-specific activation or inhibition of protein kinase C alpha were then studied to specifically examine the effects of protein kinase C alpha on myocardial preservation in this model.. Cardioplegic arrest with University of Wisconsin solution led to significantly improved postreperfusion hemodynamics and inhibition of myocardial protein kinase C alpha activity relative to that seen in saline-treated control hearts. Beta-adrenergic receptor signaling was also preserved with University of Wisconsin solution. Transgenic hearts with enhanced protein kinase C alpha activity had poor postreperfusion hemodynamics, impaired beta-adrenergic receptor signaling, and increased G protein-coupled receptor kinase 2 activity compared with those seen in nontransgenic control hearts. In contrast, transgenic hearts with inhibited protein kinase C alpha activity had even better myocardial protection relative to control hearts and preserved beta-adrenergic receptor signaling.. Current techniques of myocardial preservation are associated with inhibition of protein kinase C alpha activity and maintenance of intact beta-adrenergic receptor signaling. Activation of protein kinase C alpha leads to enhanced beta-adrenergic receptor desensitization and impaired signaling and ventricular function as a result of increased G protein-coupled receptor kinase 2 activity. This is a novel in vivo mechanism of G protein-coupled receptor kinase 2 activation. Strategies to specifically inhibit these kinases might improve long-term myocardial protection. Topics: Adenosine; Allopurinol; Animals; Cardioplegic Solutions; Cardiotonic Agents; Disease Models, Animal; Glutathione; Heart Arrest, Induced; Heart Ventricles; In Vitro Techniques; Insulin; Male; Mice; Mice, Transgenic; Myocardial Reperfusion Injury; Myocardium; Organ Preservation; Organ Preservation Solutions; Perfusion; Protein Kinase C-alpha; Raffinose; Receptors, Adrenergic, beta; Recovery of Function; Signal Transduction | 2008 |
Pancreatic islet isolation variables in non-human primates (rhesus macaques).
Non-human primates (NHPs) are important preclinical models for pancreatic islet transplantation (PIT) because of their close phylogenetic and immunological relationship with humans. However, low availability of NHP tissue, long learning curves and prohibitive expenses constrain the consistency of isolated NHP islets for PIT studies. To advance preclinical studies, we attempted to identify key variables that consistently influence the quantity and quality of NHP islets.. Seventy-two consecutive pancreatic islet isolations from rhesus macaques were reviewed retrospectively. A scaled down, semi-automated islet isolation method was used, and monkeys with streptozotocin-induced diabetes, weighing 3-7 kg, served as recipients for allotransplantation. We analysed the effects of 22 independent variables grouped as donor factors, surgical factors and isolation technique factors. Islet yields, success of isolation and transplantation results were used as quantitative and qualitative outcomes.. In the multivariate analysis, variables that significantly affected islet yield were the type of monkey, pancreas preservation, enzyme lot and volume of enzyme delivered. The variables associated with successful isolation were the enzyme lot and volume delivered. The transplant result was correlated with pancreas preservation, enzyme lot, endotoxin levels and COBE collection method.. Islet quantity and quality are highly variable between isolations. The data reviewed suggest that future NHP isolations should use bilayer preservation, infuse more than 80 ml of Liberase into the pancreas, collect non-fractioned tissue from the COBE, and strictly monitor for infection. Topics: Adenosine; Allopurinol; Animals; Diabetes Mellitus, Experimental; Disease Models, Animal; Female; Glutathione; Insulin; Islets of Langerhans; Islets of Langerhans Transplantation; Macaca mulatta; Male; Organ Culture Techniques; Organ Preservation; Organ Preservation Solutions; Raffinose | 2008 |
Microvascular experimental evidence on the relative significance of restoring oxygen carrying capacity vs. blood viscosity in shock resuscitation.
The development of volume replacement fluids for resuscitation in hemorrhagic shock comprises oxygen carrying and non carrying fluids. Non oxygen carrying fluids or plasma expanders are used up to the transfusion trigger, and upon reaching this landmark either blood, and possibly in the near future oxygen carrying blood substitutes, are used. An experimental program in hemorrhagic shock using the hamster chamber window model allowed to compare the relative performance of most fluids proposed for shock resuscitation. This model allows investigating simultaneously the microcirculation and systemic reactions, in the awake condition, in a tissue isolated from the environment. Results from this program show that in general plasma expanders such as Ringer's lactate and dextran 70 kDa do not sufficiently restore blood viscosity upon reaching the transfusion trigger, causing microvascular collapse. This is in part restored by a blood transfusion, independently of the oxygen carrying capacity of red blood cells. These results lead to the proposal that effective blood substitutes must be designed to prevent microvascular collapse, manifested in the decrease of functional capillary density. Achievement of this goal, in combination with the increase of oxygen affinity, significantly postpones the need for a blood transfusion, and lowers the total requirement of restoration of intrinsic oxygen carrying capacity. Topics: Animals; Blood Transfusion; Blood Viscosity; Blood Volume; Capillaries; Disease Models, Animal; Erythrocyte Transfusion; Hemoglobins; Humans; Hydroxyethyl Starch Derivatives; Microcirculation; NAD; Oxygen; Polyethylene Glycols; Raffinose; Resuscitation; Shock, Hemorrhagic; Vasoconstriction | 2008 |
Effects of perfusion solutions on kidney ischemia-reperfusion injury in pigs.
During ischemia-reperfusion, free oxygen radicals which directly affect renal cells may cause delayed graft function. We investigated whether there was a difference regarding antioxidant enzyme content between use of Ringer's lactate (RL) versus University of Wisconsin (UW) perfusion solutions in kidney transplantation. Ischemia was achieved by clamping the renal pedicle for 20 minutes followed by perfusion with either solution for 20 minutes and reperfusion for another 20 minutes. A parenchymal biopsy was taken before and after the ischemia, perfusion, and reperfusion (IPR) process. The levels of superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde (MDA) were investigated in the biopsy specimens. We used paired t tests within groups and t tests for comparisons between groups. The results were expressed as mean values +/- SEM with P < .05 accepted as statistically significant. After IPR, SOD, GPx, and MDA were decreased in all groups: only GPx (P = .001) and MDA (P = .04) for the RL group and SOD (P = .001) and MDA (P = .05) for the UW group were statistically significant. In the control group, we did not observe any difference (P > .05). Comparisons between groups did not reveal differences (P > .05). In our study, no difference was observed between RL and UW regarding their effects on antioxidant enzymes following renal I/R injury in pigs. More investigations are needed to evaluate graft function in this setting. Topics: Adenosine; Allopurinol; Animals; Disease Models, Animal; Glutathione; Glutathione Peroxidase; Insulin; Isotonic Solutions; Kidney Transplantation; Male; Malondialdehyde; Organ Preservation Solutions; Perfusion; Raffinose; Renal Circulation; Reperfusion Injury; Ringer's Lactate; Solutions; Swine; Thiobarbituric Acid Reactive Substances | 2006 |
Ex vivo application of carbon monoxide in University of Wisconsin solution to prevent intestinal cold ischemia/reperfusion injury.
Carbon monoxide (CO), a byproduct of heme catalysis, was shown to have potent cytoprotective and anti-inflammatory effects. In vivo recipient CO inhalation at low concentrations prevented ischemia/reperfusion (I/R) injury associated with small intestinal transplantation (SITx). This study examined whether ex vivo delivery of CO in University of Wisconsin (UW) solution could ameliorate intestinal I/R injury. Orthotopic syngenic SITx was performed in Lewis rats after 6 h cold preservation in control UW or UW that was bubbled with CO gas (0.1-5%) (CO-UW). Recipient survival with intestinal grafts preserved in 5%, but not 0.1%, CO-UW improved to 86.7% (13/15) from 53% (9/17) with control UW. At 3 h after SITx, grafts stored in 5% CO-UW showed improved intestinal barrier function, less mucosal denudation and reduced inflammatory mediator upregulation compared to those in control UW. Preservation in CO-UW associated with reduced vascular resistance (end preservation), increased graft cyclic guanosine monophosphate levels (1 h), and improved graft blood flow (1 h). Protective effects of CO-UW were reversed by ODQ, an inhibitor of soluble guanylyl cyclase. In vitro culture experiment also showed better preservation of vascular endothelial cells with CO-UW. The study suggests that ex vivo CO delivery into UW solution would be a simple and innovative therapeutic strategy to prevent transplant-induced I/R injury. Topics: Adenosine; Allopurinol; Animals; Antimetabolites; Carbon Monoxide; Disease Models, Animal; Glutathione; Graft Survival; Insulin; Intestinal Mucosa; Intestine, Small; Male; Microscopy, Electron, Transmission; Organ Preservation; Organ Preservation Solutions; Organ Transplantation; Raffinose; Rats; Rats, Inbred Lew; Reperfusion Injury; Treatment Outcome | 2006 |
Inflammatory responses in a new mouse model of prolonged hepatic cold ischemia followed by arterialized orthotopic liver transplantation.
The current models of liver ischemia/reperfusion injury (IRI) in mice are largely limited to a warm ischemic component. To investigate the mechanism of hepatic "cold" IRI, we developed and validated a new mouse model of prolonged cold preservation followed by syngeneic orthotopic liver transplantation (OLT). Two hundred and forty-three OLTs with or without rearterialization and preservation in University of Wisconsin solution at 4 degrees C were performed in Balb/c mice. The 14-day survivals in the nonarterialized OLT groups were 92% (11/12), 82% (9/11), and 8% (1/12) after 1-hour, 6-hour and 24-hour preservation, respectively. In contrast, hepatic artery reconstruction after 1-hour, 6-hour, and 24-hour preservation improved the outcome as evidenced by 2-week survival of 100% (12/12), 100% (10/10), and 33% (4/12), respectively, and diminished hepatocellular damage (serum alanine aminotransferase /histology). Moreover, 24-hour (but not 1-h) cold preservation of rearterialized OLTs increased hepatic CD4+ T-cell infiltration and proinflammatory cytokine (tumor necrosis factor-alpha, interleukin 2, interferon-gamma) production, as well as enhanced local apoptosis, and Toll-like receptor 4/caspase 3 expression. These cardinal features of hepatic IRI validate the model. In conclusion, we have developed and validated a new mouse model of IRI in which hepatic artery reconstruction was mandatory for long-term animal survival after prolonged (24-h) OLT preservation. With the availability of genetically manipulated mouse strains, this model should provide important insights into the mechanism of antigen-independent hepatic IRI and help design much needed refined therapeutic means to combat hepatic IRI in the clinics. Topics: Adenosine; Allopurinol; Animals; Apoptosis; CD4 Lymphocyte Count; Disease Models, Animal; Glutathione; Immunohistochemistry; Inflammation; Insulin; Ischemia; Liver; Liver Transplantation; Male; Mice; Mice, Inbred BALB C; Organ Preservation Solutions; Postoperative Complications; Raffinose; Reverse Transcriptase Polymerase Chain Reaction; T-Lymphocytes; Treatment Outcome | 2005 |
Evidence for a mitochondrial impact of trimetazidine during cold ischemia and reperfusion.
In organ transplantation, ischemia-reperfusion injury (IRI) has been implicated in delayed graft function (DGF) as well as in short- and long-term complications. Using an autotransplant pig kidney model, changes in renal function and morphology were determined after different periods of cold ischemia in kidneys preserved in the University of Wisconsin solution (UW), high-Na(+) version of UW (HEH) or Celsior (CEL) a newly developed high-Na(+) solution, with or without trimetazidine (TMZ). Kidney function was better preserved in CEL, UW and particularly HEH in combination with TMZ, particularly after 48 and 72 h. Mitochondria integrity was improved in TMZ-preserved groups. This study indicates that TMZ is efficiently protective against IRI even after prolonged preservation and in different preservation solutions. Topics: Adenosine; Allopurinol; Animals; Biomarkers; Cryopreservation; Disaccharides; Disease Models, Animal; Drug Evaluation, Preclinical; Electrolytes; Glutamates; Glutathione; Histidine; Insulin; Kidney Function Tests; Kidney Transplantation; Mannitol; Mitochondria; Organ Preservation; Organ Preservation Solutions; Raffinose; Receptors, GABA-A; Reperfusion Injury; Swine; Time Factors; Transplantation, Autologous; Trimetazidine | 2004 |
Maintenance of glucose-sensitive insulin secretion of cryopreserved human islets with University of Wisconsin solution and ascorbic acid-2 glucoside.
Normal human islet cells are an ideal source for pancreas-targeted cell therapies, but the availability of human donor pancreata for islet isolation is severely limited. To effectively utilize such scarce donor organs for cell therapies, it is crucial to develop an excellent isolation, effective cryopreservation, and efficient gene transfer techniques for the transportation of isolated cells. In the present study, we investigate the effect of University of Wisconsin (UW) solution and ascorbic acid-2 glucoside (AA2G) on the cryopreservation of human islets. We also evaluate the gene transfer efficiency of a lentiviral vector expressing the E. coli LacZ gene, Lt-NLS/LacZ, in human islets. Human islets were isolated with a standard digestion method at the University of Alberta. Isolated islets were transported to Japan for 40 h and then subjected to cryopreservation experiments. The following preservation solutions were tested: UW solution with 100 micro g/mL of AA2G, UW solution, 100% fetal bovine serum (FBS), and CMRL supplemented with 10% FBS. Following three months of cryopreservation, the islets were thawed and analyzed for viability, glucose-sensitive insulin secretion, proinsulin gene expression profile, and in vivo engraftment. The islets were also subjected to monolayer formation with 804G-cell-line-derived extracellular matrix (ECM), followed by Lt-NLS/LacZ transduction. The viability, morphology, glucose-sensitive insulin secretion, proinsulin gene expression, and monolayer formation efficiency of the thawed cryopreserved islets are significantly better maintained by the use of UW solution. When AA2G (100 microg/mL) is combined with UW, such parameters are further improved. The adequate engraftment of UW + AA2G-cryopreserved human islets is achieved in the liver of nude mice. Efficient Lt-NLS/LacZ transduction is identified in monolayered islets cryopreserved with UW solution with AA2G. The present work demonstrates that the combination of UW solution with AA2G (100 microg/mL) would be a useful cryopreservation means for human islets. Human islets monolayer-cultured with 804G-derived ECM are efficiently transduced with a lentiviral vector Lt-NLS/LacZ. Topics: Adenosine; Allopurinol; Animals; Ascorbic Acid; Cell Survival; Cell Transplantation; Cells, Cultured; Cryopreservation; Disease Models, Animal; DNA; Gene Transfer Techniques; Glutathione; Humans; Insulin; Insulin Secretion; Islets of Langerhans; Mice; Mice, Nude; Organ Preservation Solutions; Polymerase Chain Reaction; Raffinose; RNA; Sensitivity and Specificity; Tissue Preservation; Transplantation, Heterologous | 2004 |
Reduction of allergic airway eosinophilia by dietary raffinose in Brown Norway rats.
Oral administration of raffinose, a naturally occurring indigestible oligosaccharide, has reportedly ameliorated atopic dermatitis in human subjects although the mechanism is unknown. The present study investigated the effect of dietary raffinose on allergen-induced airway eosinophilia in ovalbumin-sensitised Brown Norway rats as an atopic disease model. Brown Norway rats were immunised by subcutaneous injection with ovalbumin on day 0 and fed either a control diet or the diet supplemented with raffinose (50 g/kg diet). The rats were exposed to aerosolised ovalbumin on day 20, and broncho-alveolar lavage fluid was obtained on the next day. The number of eosinophils in the fluid was significantly lower in the rats fed the raffinose diet than in those fed the control diet. Dietary raffinose significantly reduced IL-4 and IL-5 mRNA levels in lung tissue and tended to lower ovalbumin-specific Ig E levels. Suppression of eosinophilia by dietary raffinose was still observed in caecectomised and neomycin-administered rats, suggesting little contribution by the colonic bacteria to the effect of raffinose. Intraperitoneal administration of raffinose also suppressed eosinophilia. Significant concentrations of raffinose were detected in portal venous and abdominal arterial plasma after the intragastric administration of raffinose. Overall, the findings suggest that dietary raffinose ameliorates allergic airway eosinophilia at least partly via post-absorptive mechanisms in Brown Norway rats. Topics: Allergens; Animals; Bronchoalveolar Lavage Fluid; Cell Count; Dietary Supplements; Disease Models, Animal; Eosinophilia; Immunoglobulin E; Interleukin-4; Interleukin-5; Lung; Macrophages, Alveolar; Male; Ovalbumin; Raffinose; Rats; Rats, Inbred BN; Respiratory Hypersensitivity; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger | 2004 |
Attenuation of ischemia-reperfusion injury in a canine model of autologous renal transplantation.
This study examined the potential therapeutic effects of a combination therapy consisting of 5-aminoimidazole-4-carboxamide-1-beta-D-ribonucleoside (AICAR) and N-acetyl cysteine (NAC) to attenuate ischemia-reperfusion (I/R) injury in a canine model of autologous renal transplantation.. Male mongrel dogs (15-20 kg) underwent left nephrectomy followed by flushing and static preservation of the kidney in University of Wisconsin (UW) solution for 48 hr. The treatment group received AICAR (50 mg/kg) plus NAC (100 mg/kg) intravenously before the left nephrectomy. The compounds were added to the UW solution as well. All dogs underwent right nephrectomy 48 hr later followed by autotransplantation of the preserved left kidney. Treated dogs received a second dose of AICAR and NAC before implantation of the renal autograft.. The treated dogs had excellent urine output posttransplant, with peak serum creatinine of 7.26 mg/dL on postoperative day (POD) 3 that normalized after 14 days. The control group were anuric and developed clinical symptoms of uremia on POD 1. Morphologic evaluation supported the protective effects of combination therapy. Immunohistochemical analysis revealed decrease of tumor necrosis factor-alpha, interferon-gamma, and inducible nitric oxide synthase; and TUNEL assay showed decreased apoptosis in the treated group.. Combination therapy with AICAR and NAC attenuates renal I/R injury and improves the outcome of the transplanted kidney after prolonged cold preservation. Topics: Acetylcysteine; Adenosine; Allopurinol; Aminoimidazole Carboxamide; Animals; Apoptosis; Creatinine; Disease Models, Animal; Dogs; Glutathione; Graft Survival; Immunohistochemistry; Insulin; Kidney; Kidney Transplantation; Male; Nephrectomy; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Organ Preservation; Organ Preservation Solutions; Raffinose; Reperfusion Injury; Ribonucleotides; Transplantation, Autologous; Tumor Necrosis Factor-alpha | 2004 |
Synergistic value of fibrinolysis and hypothermic aerobic preservation with oxygen in the protection of livers from non-heart-beating donors: an experimental model.
The chronic organ shortage has led to the reconsideration of marginal donor pools such as non-heart-beating donors (NHBD). The use of these livers is limited due to their minimal tolerance for cold preservation. The aim of this study was to examine the combination of two different therapeutic strategies for the preservation of livers from NHBD. The livers of male Wistar rats were harvested after the induction of cardiac arrest via phrenotomy (30, 90 minutes). Livers were perfused with 10 mL of UW solution (UW), followed by hypothermic preservation with or without insufflation of gaseous oxygen (O2). In one group a fibrinolytic preflush (10 mL of Ringer's containing 7500 IU of streptokinase) was performed with subsequent preservation with O2 (O2+SK). After storage (24 h/4 degrees C/UW) livers were reperfused in vitro. Livers retrieved from heart beating donors served as controls. The results showed that even after only 30 minutes of warm ischemia livers displayed a serious disturbance in vascular perfusion (portal venous pressure, PVP = 7.4 +/- 0.2* versus control: 4.1 +/- 0.5 mmHg), associated with a more than 10-fold increase in enzyme release (ALT: 26819 +/- 513* versus control 683 +/- 152 mU/g/L), which was consistent with a significant depression in bile synthesis (1.21 +/- 0.35* versus 19.36 +/- 2.16 microL/g/45 min). However, these impairments could be prevented with O2. Even after 90 minutes of WI, the function was significant better using aerobic preservation (ALT: 3204 +/- 549 mU/g/L). With a supplementary fibrinolytic preflush, we effectively preserved livers up to 90 minutes of WI with results comparable to livers from heart beating donors with no WI (ALT: 1623 +/- 432 mU/g/L). The combination of these two techniques represents a new therapeutic approach for livers with extended or unclear WI periods in non-heart-beating donors (*P <.05 versus control). Topics: Adenosine; Aerobiosis; Allopurinol; Animals; Bile; Cell Death; Disease Models, Animal; Fibrinolysis; Glutathione; Heart Arrest; Hypothermia; Insulin; Liver; Male; Organ Preservation; Organ Preservation Solutions; Raffinose; Rats; Rats, Wistar; Vascular Resistance | 2004 |
Hyperphosphaturia after kidney transplantation in syngeneic rats: effects on nephrocalcinosis and bone metabolism?
Studies on kidney transplantation have thus far mainly dealt with surgical techniques, immunology, and transplant tolerance. Disturbed mineral metabolism after renal denervation has not received much attention. Basic physiological research in short-term experiments has shown that experimental renal denervation in rats leads to parathormone (PTH)-independent hyperphosphaturia (HPU). HPU and other metabolic complications also have been described after clinical kidney transplantation. Furthermore, there is an unexpected increase in the risk of bone fracture. However, these studies have examined an organism pre-damaged with regard to the parathyroid and immunosuppression. Experimental investigations in syngeneic rats were performed to see whether HPU also occurs after transplantation and thus after denervation and which target organs are involved.. Thirty-six male Lewis rats subjected to laparotomy (n = 12), unilateral nephrectomy (n = 12), or unilateral transplantation and bilateral nephrectomy (n = 12) were observed for 18 weeks.. Animals that underwent transplantation had a significant loss of phosphate in the urine not associated with decreased calcium, phosphate, or magnesium in bone. Stability test showed no deterioration, despite a slight increase in the bone parameters of alkaline phosphatase, cyclic AMP, and hydroxyproline with unchanged calciotropic hormones. Nephrocalcinosis was not observed. Parallel to HPU, there was a compensatory reduction in fecal phosphate excretion.. The loss of phosphate after clinical kidney transplantation in the predamaged parathyroid hormone control system as well as immunosuppression and a surprising increase in the incidence of bone fractures may be explained by the denervation-related loss of phosphate. The lack of intestinal counter-regulation could be an important pathomechanism. Topics: Adenosine; Allopurinol; Animals; Bone and Bones; Calcinosis; Disease Models, Animal; Glutathione; Insulin; Kidney Diseases; Kidney Transplantation; Male; Nephrectomy; Organ Preservation; Organ Preservation Solutions; Phosphates; Raffinose; Rats; Rats, Inbred Lew; Tissue and Organ Harvesting; Transplantation, Isogeneic; Urinalysis | 2003 |
The CF salt controversy: in vivo observations and therapeutic approaches.
There is controversy over whether abnormalities in the salt concentration or volume of airway surface liquid (ASL) initiate cystic fibrosis (CF) airway disease. In vivo studies of CF mouse nasal epithelia revealed an increase in goblet cell number that was associated with decreased ASL volume rather than abnormal [Cl(-)]. Aerosolization of osmolytes in vivo failed to raise ASL volume. In vitro studies revealed that osmolytes and pharmacological agents were effective in producing isotonic volume responses in human airway epithelia but were typically short acting and less effective in CF cultures with prolonged volume hyperabsorption and mucus accumulation. These data show that (1) therapies can be designed to normalize ASL volume, without producing deleterious compositional changes in ASL, and (2) therapeutic efficacy will likely depend on development of long-acting pharmacologic agents and/or an increased efficiency of osmolyte delivery. Topics: Aerosols; Amiloride; Animals; Cells, Cultured; Cystic Fibrosis; Disease Models, Animal; Diuretics; Goblet Cells; Humans; Ion Transport; Mice; Mice, Inbred C57BL; Microdialysis; Microscopy, Confocal; Mucus; Nasal Mucosa; Osmolar Concentration; Pulmonary Surfactants; Raffinose; Respiratory Mucosa; Sodium Chloride; Uridine Triphosphate | 2001 |
o-raffinose cross-linked hemoglobin improves the hemostatic defect associated with anemia and thrombocytopenia in rabbits.
Several different preparations of cross-linked hemoglobin (CLHb) are being evaluated for their efficacy and safety as red cell substitutes in a variety of preclinical and clinical settings. Because CLHb is known to sequester nitric oxide (NO) and inhibit NO-mediated processes, we hypothesized that CLHb would have a hemostatic effect by enhancing platelet reactivity, inducing vasoconstriction, or both. Infusion of o-raffinose CLHb shortened the prolonged microvascular bleeding time and decreased blood loss from ear incisions in rabbits rendered anemic and thrombocytopenic. Moreover, this hemostatic effect persisted for at least 24 hours after infusion. Phenylephrine induced a degree of vasoconstriction similar to that induced by CLHb but did not shorten the bleeding time or decrease blood loss, suggesting that vasoconstriction alone cannot account for the hemostatic effect of CLHb. There was no evidence of CLHb-induced activation of coagulation in vivo, since infusion of CLHb did not increase circulating levels of thrombin-antithrombin complex. In vitro, CLHb abolished the inhibitory effect of the NO donor 3-morpholinosydnonimine on platelet aggregation and enhanced the aggregation of stimulated but not resting platelets. This potentiating effect was not attenuated by the addition of superoxide dismutase or catalase. To evaluate the potential arterial thrombogenicity of CLHb, a model of carotid artery thrombosis was developed in rabbits without thrombocytopenia or anemia. Compared with albumin infusion, CLHb infusion shortened the time to complete carotid occlusion. These data suggest that CLHb may shift the thromboregulatory balance toward clot formation, resulting in decreased bleeding in anemic and thrombocytopenic rabbits and possibly increasing arterial thrombogenicity in normal rabbits. Topics: Adrenergic alpha-Agonists; Anemia; Animals; Antithrombin III; Bleeding Time; Carotid Artery Thrombosis; Cross-Linking Reagents; Disease Models, Animal; Dose-Response Relationship, Drug; Hemoglobins; Hemorrhage; Hemostasis; Kinetics; Male; Microcirculation; Peptide Hydrolases; Phenylephrine; Platelet Aggregation; Rabbits; Raffinose; Rats; Rats, Sprague-Dawley; Serum Albumin; Thrombocytopenia; Vasoconstriction | 2000 |
Superior protection in orthotopic rat lung transplantation with cyclic adenosine monophosphate and nitroglycerin-containing preservation solution.
Primary lung graft failure is common, and current lung preservation strategies are suboptimal. Because the decline in lung levels of cyclic adenosine monophosphate and cyclic guanosine monophosphate during preservation could enhance adhesiveness of endothelial cells for leukocytes as well as increase vascular permeability and vasoconstriction, we hypothesized that buttressing these levels by means of a preservation solution would significantly improve lung preservation.. An orthotopic rat left lung transplantation model was used. Lungs were harvested from male Lewis rats and preserved for 6 hours at 4 degrees C with (1) Euro-Collins solution (n = 8); (2) University of Wisconsin solution (n = 8); (3) low-potassium dextran glucose solution (n = 8); (4) Columbia University solution (n = 8), which contains a cyclic adenosine monophosphate analog (dibutyryl cyclic adenosine monophosphate) and a nitric oxide donor (nitroglycerin) to buttress cyclic guanosine monophosphate levels; or (5) Columbia University solution without cyclic adenosine monophosphate or nitroglycerin (n = 8). PaO2, pulmonary vascular resistance, and recipient survival were evaluated 30 minutes after left lung transplantation and removal of the nontransplanted right lung from the pulmonary circulation.. Among all groups studied, grafts stored with Columbia University solution demonstrated the highest Pa O2 (355 +/- 25 mm Hg for Columbia University solution versus 95 +/- 22 mm Hg for Euro-Collins solution, P <.01, 172 +/- 55 mm Hg for University of Wisconsin solution, P <.05, 76 +/- 15 mm Hg for low-potassium dextran glucose solution, P <.01, and 82 +/- 25 mm Hg for Columbia University solution without cyclic adenosine monophosphate or nitroglycerin, P <.01) and the lowest pulmonary vascular resistances (1 +/- 0.2 mm Hg * mL-1 * min-1 for Columbia University solution versus 12 +/- 4 mm Hg * mL-1 * min-1 for Euro-Collins solution, P <.01, 9 +/- 2 mm Hg * mL-1 * min-1 for University of Wisconsin solution, 14 +/- 6 mm Hg * mL-1 * min-1 for low-potassium dextran glucose solution, P <.01, and 8 +/- 2 mm Hg * mL-1 * min-1 for Columbia University solution without cyclic adenosine monophosphate and nitroglycerin). These functional and hemodynamic improvements provided by Columbia University solution were accompanied by decreased graft leukostasis and decreased recipient tumor necrosis factor alpha and interleukin 1alpha levels compared with the other groups. In toto, these improvements translated into superior survival among recipients of Columbia University solution-preserved grafts (100% for Columbia University solution, 37% for Euro-Collins solution, P <.01, 50% for University of Wisconsin solution, P <.05, 50% for low-potassium dextran glucose solution, P <.05, and 13% for Columbia University solution without cyclic adenosine monophosphate and nitroglycerin, P <.01).. Nitroglycerin and cyclic adenosine monophosphate confer beneficial vascular effects that make Columbia University solution a superior lung preservation solution in a stringent rat lung transplantation model. Topics: Adenosine; Allopurinol; Animals; Capillary Permeability; Cyclic AMP; Dextrans; Disease Models, Animal; Drug Evaluation, Preclinical; Glucose; Glutathione; Graft Survival; Hypertonic Solutions; Insulin; Lung Transplantation; Male; Nitroglycerin; Organ Preservation Solutions; Pulmonary Circulation; Raffinose; Rats; Rats, Inbred Lew; Survival Analysis; Vasodilator Agents | 1999 |
Low-potassium University of Wisconsin solution for cardioplegia: improved protection of the isolated ischemic neonatal rabbit heart.
Recovery of cardiac function and high-energy phosphates following ischemia and reperfusion were determined for hearts perfused with low potassium University of Wisconsin solution, high potassium University of Wisconsin solution, St Thomas' solution, or subjected to hypothermia alone. Isolated hearts were arrested for either 3 h at 15 degrees C or 6 h at 20 degrees C (n = 7 for each group) with one of the four solutions and then reperfused. Aortic flow after ischemic arrest at 20 degrees C was 40.3 +/- 13.3%, 79.3 +/- 10.0%, 64.3 +/- 11.9% and 43.9 +/- 15.9% of control values for high potassium University of Wisconsin solution, low potassium University of Wisconsin solution, St Thomas' solution and hypothermia alone, respectively. Similar results were observed in hearts subjected to ischemic arrest at 15 degrees C. Myocardial adenosine triphosphate and creatine phosphate after reperfusion tended to be higher in the low potassium University of Wisconsin solution group. It is concluded that low potassium University of Wisconsin solution may provide reliable cardioplegia during surgery that requires prolonged cardiac arrest in neonates and infants. Topics: Adenosine; Adenosine Triphosphate; Allopurinol; Animals; Animals, Newborn; Bicarbonates; Calcium Chloride; Cardioplegic Solutions; Disease Models, Animal; Dose-Response Relationship, Drug; Glutathione; Heart; Heart Arrest; Heart Arrest, Induced; Hemodynamics; Hypothermia, Induced; In Vitro Techniques; Insulin; Magnesium; Organ Preservation Solutions; Phosphocreatine; Potassium; Potassium Chloride; Rabbits; Raffinose; Sodium Chloride | 1999 |
Hypothermic ischaemia of the liver: a re-perfusion phenomenon.
The effects of hypothermic injury to the liver were investigated on an isolated perfusion circuit by comparing porcine livers with varying degrees of preservation injury.. A group of unstored livers (n = 5) were compared to livers stored in University of Wisconsin (UW) solution for 18 h (n = 5), and a group of livers stored in Hartmann's solution for 18 h (n = 5).. We observed that the degree of platelet sequestration was directly related to the severity of the preservation injury. After 2 h of isolated liver perfusion, the perfusate platelet count fell from 148 +/- 14 x 10(9)/L to 84 +/- 13 x 10(9)/L for control livers. In comparison for livers stored in UW solution, the platelet count fell from 173 +/- 43 x 10(9)/L to 61 +/- 14 x 10(9)/L representing a 64.8% fall, while for those stored in Hartmann's solution, an even more profound fall from 152 +/- 36 x 10(9)/L to 19 +/- 9 x 10(9)/L (87.5% fall) was observed. The difference between the UW-stored and Hartmann's-stored livers was significant (P < 0.05). However, using this model, the degree of leukocyte sequestration did not differentiate the groups. Both histological and ultrastructural examination of liver biopsies taken immediately following revascularization demonstrated that for mild degrees of preservation injury following hypothermic storage, changes occur to the sinusoidal lining cells well before changes to the parenchymal elements.. These findings substantiate the hypothesis that the primary injury associated with hypothermia involves the sinusoidal lining cells (non-parenchymal elements), that it is predominantly a reperfusion phenomenon and that efforts at improving preservation should therefore be targeted primarily at these cells and not the hepatocytes. Topics: Adenosine; Allopurinol; Animals; Biopsy; Cryopreservation; Disease Models, Animal; Glutathione; Insulin; Isotonic Solutions; Liver; Liver Function Tests; Organ Preservation; Organ Preservation Solutions; Platelet Count; Raffinose; Reperfusion Injury; Ringer's Lactate; Swine | 1997 |
Energy status in anoxic rat hepatocytes: effects of isoflurane, solution composition, and hypothermia.
Both cold and warm ischemia occur during liver transplantation. Hypothermia and Wisconsin solution preserve adenine nucleotide energy status, which is crucial to hepatic function and viability. The volatile anesthetic isoflurane has been shown to preserve energy status in anoxic isolated hepatocytes in warm Krebs solution. The present study examined isoflurane effects on energy status during incubation also in Wisconsin or Krebs-plus-adenosine solution at 37 degrees or 4 degrees. Hepatocytes were isolated from rat liver after perfusion with Krebs + collagenase. In 25-mL flasks, 12.5 million cells in 2.5 mL of Krebs, Krebs plus 5 mmol/L adenosine, or Wisconsin solution were incubated under an atmosphere of O2/CO2 or N2/CO2 (19:1) +/- isoflurane (3 volumes% = 2ED50), for 30 minutes at 37 degrees C or 4 degrees C. Adenine nucleotides were measured by high-performance liquid chromatography (HPLC), lactate enzymatically. During warm (37 degrees) anoxia, Wisconsin solution preserved energy status; Krebs plus adenosine did not. Isoflurane further protected energy status in all three solutions. Hypothermia (4 degrees) alone greatly decreased anoxic loss of energy status in all solutions. In Wisconsin solution only, energy status tended to be higher in anoxic than in oxygenated cells and was further enhanced by isoflurane, with corresponding increases in lactate. During 30 minutes of either warm or cold anoxia, isoflurane and Wisconsin solution each helped preserve adenine nucleotide energy status in isolated hepatocytes, at least in part through enhanced glycolysis. Topics: Adenine Nucleotides; Adenosine; Allopurinol; Anesthetics, Inhalation; Animals; Cell Hypoxia; Chromatography, High Pressure Liquid; Disease Models, Animal; Energy Metabolism; Glutathione; Hypothermia, Induced; Hypoxia; Insulin; Isoflurane; Isotonic Solutions; Liver; Male; Organ Preservation Solutions; Raffinose; Rats; Rats, Sprague-Dawley | 1995 |
Protection of the right ventricular myocardium during acute right heart failure from pulmonary hypertension.
Protection of the failing right ventricle (RV) in the surgical treatment of massive pulmonary embolism is a keystone for myocardial recovery. This study evaluated whether cardioplegia should be used or avoided. In a modified Langendorff rat heart model pulmonary embolism was simulated by afterload elevation (20 cm H2O) for 30 min. Hearts were arrested with cardioplegic solutions [St. Thomas Hospital (ST); University of Wisconsin (UW); oxygenated Krebs-Henseleit-Potassium (KHP)] and stored for 10 min or were allowed to beat empty (NoCP) for 15 min. After reestablishing of baseline conditions groups were measured for 60 min. Cardiac index (CI) decreased in all groups to 20% during afterload elevation. Group NoCP showed 68 and Group ST 65% recovery after 10 min and deteriorated after 30 min. After 60 min CI was 37 (ST) and 39% (NoCP). UW and KHP showed a significantly better recovery (KHP 100%; UW 88%). At 60 min CI decreased to 60 (KHP) and 64% (UW), but was still significantly higher than corresponding values of NoCP and ST. Following increased pulmonary afterload cardioplegia with UW or KHP solution is beneficial for RV recovery. The composition of the cardioplegia is obviously important and needs further study. Topics: Acute Disease; Adenosine; Allopurinol; Animals; Cardioplegic Solutions; Disease Models, Animal; Embolectomy; Evaluation Studies as Topic; Extracorporeal Circulation; Glucose; Glutathione; Heart Arrest, Induced; Heart Failure; Hypertension, Pulmonary; Insulin; Male; Myocardial Reperfusion Injury; Organ Preservation Solutions; Pulmonary Embolism; Raffinose; Rats; Rats, Inbred Lew; Tromethamine; Ventricular Function, Right | 1994 |