mocetinostat and Reperfusion-Injury

COVID-19 as a viral disease has brought up the need to exercise more than before due to its physiological effects on health. Therefore, this study investigates the effect of 12-week of aerobic exercise on female students' hormone levels and lipid profile with polycystic ovary syndrome (PCOS) during the COVID-19 pandemic.. Using a 12-week quasi-experimental with pretest, posttest research design among 40 Iranian female students aged 18-14 with PCOS, we randomly allocated the participants to either an experimental (they performed aerobic exercises three 60-minute sessions per week at home using content production) or a control condition. Their anthropometric and blood samples (e.g., testosterone, estrogen, prolactin, and lipid profile) were taken in two stages before and after the training protocol.. Findings demonstrated that performing aerobic exercises is an effective and non-invasive method that could have a positive effect on young girls' PCOS during COVID-19 pandemic.. La pandémie de COVID-19, en tant que maladie virale, a fait ressortir la nécessité de faire de l’exercice plus que jamais en raison de ses effets physiologiques sur la santé. Par conséquent, cette étude examine l’effet de 12 semaines d’exercice aérobique sur les niveaux hormonaux et le profil lipidique d’étudiantes atteintes du syndrome d’ovaires polykystiques (SOPK) pendant la pandémie de COVID-19.. En utilisant un modèle de recherche quasi-expérimental de 12 semaines avec pré-test, post-test auprès de 40 étudiantes iraniennes âgées de 18 à 14 ans atteintes du SOPK, nous avons réparti au hasard les participantes entre une série expérimentale (elles ont effectué des exercices aérobiques à raison de trois séances de 60 minutes par semaine à la maison) et une série contrôle. Les échantillons anthropométriques et sanguins (testostérone, œstrogène, prolactine et profil lipidique) ont été prélevés en deux étapes, avant et après le protocole d’entraînement.. Les résultats ont démontré que la pratique d’exercices d’aérobic est une méthode efficace et non invasive qui pourrait avoir un effet positif sur le SOPK des jeunes filles pendant la pandémie de COVID-19.. Our research showed that even less than 5 GBq irradiation could induce a transient testicular dysfunction in the first 3 months of therapy, but it was mostly reversible after 12 months.. The online version contains supplementary material available at 10.1007/s13204-023-02822-5.. Embelin is predicted to have a high probability of immunotoxicity potential and affect drug metabolism by inhibiting CYP2D6. In addition, it affects food intake, weight gain, and the number of implantations in pregnant rats. Therefore, it is highly recommended not to take embelin and embelin-rich plants during pregnancy. Further. The online version contains supplementary material available at 10.1007/s42965-023-00306-9.. The online version contains supplementary material available at 10.1007/s11696-023-02771-x.. The online version contains supplementary material available at 10.1007/s00477-023-02476-3.. This study ascribes for a new immunomodulatory role for IL11 during tumor development that is amenable to anti-cytokine based therapy of colon cancer.. Inflammation response do not seem to be enough to explain all the Essure-related adverse outcomes, suggesting the involvement of other biological mechanisms.. NCT03281564.. Inflammation and fibrosis are found in the surrounding tubal tissue around the Essure. Adult patients with BED with co-occurring obesity who have good responses to acute treatment with naltrexone/bupropion should be offered maintenance treatment with naltrexone/bupropion.. dp/dtmax in PiCCO parameter can be used as a bedside indicator to evaluate cardiac function in SIC patients due to its simplicity and ease of operation. Esmolol control of heart rate in SIC patients can improve cardiac function and reduce short-term mortality.. Inverted microscopy showed that compared with the NC group, the OGD/R group had poor cell status, swollen cytosol, visible cell lysis fragments and significantly lower cell activity [(49.1±2.7)% vs. (100.0±9.7)%, P < 0.01]; compared with the OGD/R group, the HW group had improved cell status and remarkably higher cell activity [(63.3±1.8)% vs. (49.1±2.7)%, P < 0.01]. Transmission electron microscopy showed that the neuronal nuclear membrane of cells in the OGD/R group was lysed and a higher number of autophagic lysosomes were visible compared with the NC group; compared with the OGD/R group, the neuronal damage of cells in the HW group was reduced and the number of autophagic lysosomes was notably decreased. The results of immunofluorescence assay showed that the expressions of LC3 and Beclin-1 were outstandingly enhanced in the OGD/R group compared with the NC group, and the expressions of LC3 and Beclin-1 were markedly weakened in the HW group compared with the OGD/R group. Western blotting assay showed that the expressions were prominently higher in both LC3II/I and Beclin-1 in the OGD/R group compared with the NC group (LC3II/I: 1.44±0.05 vs. 0.37±0.03, Beclin-1/β-actin: 1.00±0.02 vs. 0.64±0.01, both P < 0.01); compared with the OGD/R group, the protein expression of both LC3II/I and Beclin-1 in the HW group cells were notably lower (LC3II/I: 0.54±0.02 vs. 1.44±0.05, Beclin-1/β-actin: 0.83±0.07 vs. 1.00±0.02, both P < 0.01).. Hydrogen-rich water has a significant protective effect on OGD/R-causing HT22 cell injury, and the mechanism may be related to the inhibition of autophagy.. The prevalence of delirium in ICU patients is over 50%, with hypoactive delirium being the most common. Age, APACHE score at ICU admission, neurological disease, sepsis and duration of mechanical ventilation were all independent risk factors for the development of delirium in ICU patients. More than half of patients with delirium were still delirious when they discharged from the ICU.. For individuals ≥75 years, plasma Aβ42 and P-tau181 might not be associated with cognitive impairment, and MRI parameters, including PVWMH, LVBI and cortical atrophy, are related to CI. The cognitive statuses of people over 75 years old were used as the endpoint event in this study. Therefore, it can be considered that these MRI markers might have more important clinical significance for early assessment and dynamic observation, but more studies are still needed to verify this hypothesis.. We recommend using the Art/Zn complex owing to its moderate inhibitory and antiviral effects against the SARS-CoV-2 with a low cytotoxic effect on host (Vero E6) cells. We suggest conducting further prospective studies to investigate the biological effects of Art/Zn in animal models at different concentrations for testing its clinical efficacy and safety in inhibiting SARS-CoV-2 activities.. The R/T sequence resulted in a significantly longer OS and PFS and improved disease control compared with the reverse sequence. R and T given not sequentially have similar impacts on survival. More data are needed to define the best sequence and to explore the efficacy of sequential (T/R or R/T) treatment combined with molecular-targeted drugs.

Topics: Actin Cytoskeleton; Actins; Adaptor Proteins, Signal Transducing; Adenocarcinoma; Adenosine Triphosphate; Adsorption; Adult; Africa, Eastern; Aged; Air Pollutants; Air Pollution; Air Pollution, Indoor; Alcohol Drinking; Allergens; Alzheimer Disease; Amyotrophic Lateral Sclerosis; Animals; Anti-Bacterial Agents; Antibodies; Antibodies, Immobilized; Antigen Presentation; Antigens, CD; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Antioxidants; Apoptosis; Aptamers, Nucleotide; Asthma; Asthma, Exercise-Induced; Atrophy; Autophagy; Azoospermia; Bacillus cereus; Bacterial Infections; Beclin-1; Bile Duct Neoplasms; Bile Ducts, Intrahepatic; Biofouling; Biological Monitoring; Biomarkers; Biomarkers, Tumor; Biosensing Techniques; Blastocyst; Bone Neoplasms; Bone Regeneration; Bronchoconstriction; Burkitt Lymphoma; C9orf72 Protein; Campylobacter; Campylobacter Infections; Campylobacter jejuni; Carcinogenesis; Carcinoma, Hepatocellular; Carcinoma, Pancreatic Ductal; Carcinoma, Squamous Cell; Cardiomyopathies; Caregivers; Carmine; Case-Control Studies; Catalysis; Cattle; Cause of Death; CCAAT-Enhancer-Binding Protein-alpha; CD8-Positive T-Lymphocytes; Cefepime; Cell Differentiation; Cell Line, Tumor; Cell Nucleus; Cell Transdifferentiation; Chelating Agents; Chemical and Drug Induced Liver Injury, Chronic; Chemoradiotherapy, Adjuvant; Child; Child, Preschool; China; Chlorquinaldol; Cholangiocarcinoma; Cholera; Chromatin; Clinical Trials as Topic; Cognitive Dysfunction; Cohort Studies; Colonic Neoplasms; Colorectal Neoplasms; Colorimetry; Cooking; Coordination Complexes; COVID-19; Creatinine; CRISPR-Cas Systems; Critical Care; Critical Illness; Cross-Sectional Studies; Cryopreservation; Cryoprotective Agents; Cysteine; Cytokines; Device Removal; Diet; Diet, High-Fat; Diet, Mediterranean; Dietary Supplements; Dimethyl Sulfoxide; Dipeptides; Disease Models, Animal; Dithiothreitol; DNA; DNA Repeat Expansion; DNA, Bacterial; DNA, Complementary; Dopamine; Electrochemical Techniques; Electrodes; Endocannabinoids; Environmental Exposure; Environmental Monitoring; Environmental Pollutants; Enzyme-Linked Immunosorbent Assay; Erlotinib Hydrochloride; Escherichia coli; Escherichia coli O157; Esophageal Neoplasms; Esophagitis, Peptic; Ethylene Glycol; Europium; Exanthema; Fallopian Tubes; Feces; Female; Fertilization in Vitro; Fluoresceins; Fluorescent Dyes; Follicle Stimulating Hormone; Follow-Up Studies; Food Microbiology; Forced Expiratory Volume; Forkhead Transcription Factors; Frontotemporal Dementia; G-Quadruplexes; Galactose; Gastroenteritis; Gastrointestinal Diseases; Gastrointestinal Microbiome; Gastrointestinal Neoplasms; Gastrointestinal Tract; Gene Frequency; Genetic Association Studies; Genetic Predisposition to Disease; Genital Neoplasms, Female; Genome-Wide Association Study; Genome, Viral; Genomics; Genotype; Glucose; Glutathione; Glycerol; Gold; Graphite; GTPase-Activating Proteins; Heat-Shock Proteins; Heme Oxygenase-1; Hepacivirus; Hepatitis C; Hepatocytes; Histamine; Histocompatibility Antigens Class II; Hoarseness; Hospice and Palliative Care Nursing; Humans; Hydrogen; Hydrogen Peroxide; Hydrogen Sulfide; Hydroxybenzoates; Hydroxyl Radical; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Hyperthermia, Induced; Hysteroscopy; Immunoassay; Indigo Carmine; Inflammation; Inflammatory Bowel Diseases; Insulin Resistance; Intensive Care Units; Interleukin-11; Interleukin-6; Interleukins; Iodine Radioisotopes; Iran; Iridium; Islets of Langerhans; Kinetics; Lactation; Lactobacillus; Lactobacillus plantarum; Lamins; Latin America; Lead; Lectins; Leukopenia; Ligands; Limit of Detection; Lipopolysaccharides; Lipoprotein Lipase; Liver; Liver Cirrhosis; Liver Neoplasms; Lolium; Luminescent Measurements; Luminol; Lung; Luteinizing Hormone; Macrophages; Magnetic Phenomena; Magnetic Resonance Imaging; Male; Malnutrition; Maltose; Manganese Compounds; Maternal Nutritional Physiological Phenomena; Melatonin; Metabolic Engineering; Metal Nanoparticles; Metallocenes; Metaplasia; Methicillin-Resistant Staphylococcus aureus; Methylation; Mevalonic Acid; Mexico; Mice; Mice, Inbred C57BL; Mice, Transgenic; Microbial Sensitivity Tests; Microbiota; MicroRNAs; Milk; Mitomycin; Molecular Diagnostic Techniques; Molecular Docking Simulation; Monte Carlo Method; Moringa oleifera; Multiple Sclerosis; Muscle Strength; Muscle, Skeletal; Nanocomposites; Nanotubes, Carbon; Neoadjuvant Therapy; Neoplasms; Neurodegenerative Diseases; Neurotransmitter Agents; NF-E2-Related Factor 2; Nickel; Nitrogen Dioxide; Non-alcoholic Fatty Liver Disease; Nucleic Acid Amplification Techniques; Nucleic Acid Hybridization; Nucleocapsid Proteins; Nutritional Status; Obesity; Osteogenesis; Osteosarcoma; Oxidation-Reduction; Oxides; Oxygen; Oxyquinoline; Pain; Palliative Care; Pancreatic Neoplasms; Pandemics; Particulate Matter; Peroxidase; Peroxidases; Phagocytosis; Phaseolus; Photothermal Therapy; Point-of-Care Systems; Polyethyleneimine; Polymers; Polymorphism, Single Nucleotide; Polysomnography; Postoperative Complications; Pregnancy; Pregnant Women; Prenatal Exposure Delayed Effects; Prevalence; Printing, Three-Dimensional; Probability; Probiotics; Prognosis; Prophages; Prospective Studies; Proteomics; Proto-Oncogene Proteins; Pseudomonas aeruginosa; Pseudomonas putida; Pulmonary Disease, Chronic Obstructive; Pulmonary Embolism; Pyridines; Pyrroles; Quality of Life; Quinolones; Rabbits; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Real-Time Polymerase Chain Reaction; Receptors, Histamine; Receptors, Histamine H2; Recombinases; Rectal Neoplasms; Reperfusion Injury; Respiration; Respiratory Function Tests; Respiratory Rate; Respiratory Sounds; Retrospective Studies; rho GTP-Binding Proteins; Risk Assessment; Risk Factors; RNA; RNA, Messenger; RNA, Ribosomal, 16S; Robotic Surgical Procedures; Running; Rural Population; Saccharomyces cerevisiae; Salpingectomy; Sarcopenia; SARS-CoV-2; Seeds; Semen; Sensitivity and Specificity; Sepsis; Shock, Septic; Signal Transduction; Silicon Dioxide; Silver; Sirtuin 1; Skin Neoplasms; Sleep Apnea, Obstructive; Soil; Spain; Spectrum Analysis, Raman; Sperm Retrieval; Spermatozoa; Spirometry; Staphylococcus aureus; STAT3 Transcription Factor; Stereoisomerism; Sterilization, Tubal; Stroke Volume; Sulfadiazine; Sulfites; Superoxide Dismutase; Surface Plasmon Resonance; tau Proteins; Testis; Testosterone; Thioredoxin-Disulfide Reductase; Thyroid Neoplasms; Thyroidectomy; Trans-Activators; Transcription Factor AP-1; Treatment Outcome; Triazoles; Triclosan; Trifluridine; Tumor Microenvironment; Tumor Necrosis Factor-alpha; United States; Uracil; Vagina; Vegetables; Ventricular Function, Left; Ventricular Pressure; Vibrio cholerae; Vietnam; Virulence; Vital Capacity; Vitrification; Walking; Water; Water Pollutants, Radioactive; Whole Genome Sequencing; Wind; YAP-Signaling Proteins; Zeolites; Zinc Oxide

In glomerular and tubulointerstitial disease, polymorphonuclear- and monocyte-derived reactive oxygen species may contribute to oxidative modification of proteins, lipids, and nucleic acids. In part, the processes instigated by reactive oxygen species parallel events that lead to the development of atherosclerosis. Myeloperoxidase (MPO), a heme protein and catalyst for (lipo)protein oxidation is present in these mononuclear cells. The ability of MPO to generate hypochlorous acid/hypochlorite (HOCl/OCl-) from hydrogen peroxide in the presence of chloride ions is a unique and defining activity for this enzyme. The MPO-hydrogen peroxide-chloride system leads to a variety of chlorinated protein and lipid adducts that in turn may cause dysfunction of cells in different compartments of the kidney. The aim of this article is to cover and interpret some experimental and clinical aspects in glomerular and tubulointerstitial diseases in which the MPO-hydrogen peroxide-chloride system has been considered an important pathophysiologic factor in the progression but also the attenuation of experimental renal disease. The colocalization of MPO and HOCl-modified proteins in glomerular peripheral basement membranes and podocytes in human membranous glomerulonephritis, the presence of HOCl-modified proteins in mononuclear cells of the interstitium and in damaged human tubular epithelia, the inflammation induced and exacerbated by MPO antibody complexes in necrotizing glomerulonephritis, and the presence of HOCl-modified epitopes in urine following hyperlipidemia-induced renal damage in rodents suggest that MPO is an important pathogenic factor in glomerular and tubulointerstitial diseases. Specifically, the interaction of MPO with nitric oxide metabolism adds to the complexity of actions of oxidants and may help to explain bimodal partly detrimental partly beneficial effects of the MPO-hydrogen peroxide-chloride system in redox-modulated renal diseases.

Topics: Animals; Disease Progression; Humans; Hypochlorous Acid; Immune System Diseases; Kidney Diseases; Kidney Glomerulus; Oxidation-Reduction; Peroxidase; Renal Circulation; Reperfusion Injury

1. Cypridina luciferin analogues, 2-methyl-6-(p-methoxyphenyl)-3,7- dihydroimidazo[1,2-a]pyrazin-3-one (MCLD) and 2-methyl-6-phenyl-3,7-dihydroimidazo[1,2-a]pyrazin-3-one(CLA ), react with O2- or 1O2 to emit light in visible region. Such chemiluminescences were used for the detection of O2- or 1O2 in activated leukocyte systems and myeloperoxidase (granulocyte-extract) + Br- + H2O2 systems in vitro. 2. The mechanisms of MCLA (CLA)-dependent luminescence is described in detail. Superoxide generated from sinusoidal cells in acute ethanol intoxication of rats was detected by MCLA-dependent luminescence from the surface of perfused rat liver (organ luminescence). 3. Furthermore, with alive animals, O2- generated in the lung of rats with necrotized pancreatitis and that in the stomach of rats after ischemia/reperfusion were detected by their organ luminescences.

Topics: Alcoholic Intoxication; Animals; Firefly Luciferin; Gastric Mucosa; Granulocytes; Humans; Leukocytes; Liver; Luminescent Measurements; Lung; Necrosis; Neutrophils; Pancreatitis; Peroxidase; Rats; Reactive Oxygen Species; Reperfusion Injury; Stomach; Superoxides

COVID-19 as a viral disease has brought up the need to exercise more than before due to its physiological effects on health. Therefore, this study investigates the effect of 12-week of aerobic exercise on female students' hormone levels and lipid profile with polycystic ovary syndrome (PCOS) during the COVID-19 pandemic.. Using a 12-week quasi-experimental with pretest, posttest research design among 40 Iranian female students aged 18-14 with PCOS, we randomly allocated the participants to either an experimental (they performed aerobic exercises three 60-minute sessions per week at home using content production) or a control condition. Their anthropometric and blood samples (e.g., testosterone, estrogen, prolactin, and lipid profile) were taken in two stages before and after the training protocol.. Findings demonstrated that performing aerobic exercises is an effective and non-invasive method that could have a positive effect on young girls' PCOS during COVID-19 pandemic.. La pandémie de COVID-19, en tant que maladie virale, a fait ressortir la nécessité de faire de l’exercice plus que jamais en raison de ses effets physiologiques sur la santé. Par conséquent, cette étude examine l’effet de 12 semaines d’exercice aérobique sur les niveaux hormonaux et le profil lipidique d’étudiantes atteintes du syndrome d’ovaires polykystiques (SOPK) pendant la pandémie de COVID-19.. En utilisant un modèle de recherche quasi-expérimental de 12 semaines avec pré-test, post-test auprès de 40 étudiantes iraniennes âgées de 18 à 14 ans atteintes du SOPK, nous avons réparti au hasard les participantes entre une série expérimentale (elles ont effectué des exercices aérobiques à raison de trois séances de 60 minutes par semaine à la maison) et une série contrôle. Les échantillons anthropométriques et sanguins (testostérone, œstrogène, prolactine et profil lipidique) ont été prélevés en deux étapes, avant et après le protocole d’entraînement.. Les résultats ont démontré que la pratique d’exercices d’aérobic est une méthode efficace et non invasive qui pourrait avoir un effet positif sur le SOPK des jeunes filles pendant la pandémie de COVID-19.. Our research showed that even less than 5 GBq irradiation could induce a transient testicular dysfunction in the first 3 months of therapy, but it was mostly reversible after 12 months.. The online version contains supplementary material available at 10.1007/s13204-023-02822-5.. Embelin is predicted to have a high probability of immunotoxicity potential and affect drug metabolism by inhibiting CYP2D6. In addition, it affects food intake, weight gain, and the number of implantations in pregnant rats. Therefore, it is highly recommended not to take embelin and embelin-rich plants during pregnancy. Further. The online version contains supplementary material available at 10.1007/s42965-023-00306-9.. The online version contains supplementary material available at 10.1007/s11696-023-02771-x.. The online version contains supplementary material available at 10.1007/s00477-023-02476-3.. This study ascribes for a new immunomodulatory role for IL11 during tumor development that is amenable to anti-cytokine based therapy of colon cancer.. Inflammation response do not seem to be enough to explain all the Essure-related adverse outcomes, suggesting the involvement of other biological mechanisms.. NCT03281564.. Inflammation and fibrosis are found in the surrounding tubal tissue around the Essure. Adult patients with BED with co-occurring obesity who have good responses to acute treatment with naltrexone/bupropion should be offered maintenance treatment with naltrexone/bupropion.. dp/dtmax in PiCCO parameter can be used as a bedside indicator to evaluate cardiac function in SIC patients due to its simplicity and ease of operation. Esmolol control of heart rate in SIC patients can improve cardiac function and reduce short-term mortality.. Inverted microscopy showed that compared with the NC group, the OGD/R group had poor cell status, swollen cytosol, visible cell lysis fragments and significantly lower cell activity [(49.1±2.7)% vs. (100.0±9.7)%, P < 0.01]; compared with the OGD/R group, the HW group had improved cell status and remarkably higher cell activity [(63.3±1.8)% vs. (49.1±2.7)%, P < 0.01]. Transmission electron microscopy showed that the neuronal nuclear membrane of cells in the OGD/R group was lysed and a higher number of autophagic lysosomes were visible compared with the NC group; compared with the OGD/R group, the neuronal damage of cells in the HW group was reduced and the number of autophagic lysosomes was notably decreased. The results of immunofluorescence assay showed that the expressions of LC3 and Beclin-1 were outstandingly enhanced in the OGD/R group compared with the NC group, and the expressions of LC3 and Beclin-1 were markedly weakened in the HW group compared with the OGD/R group. Western blotting assay showed that the expressions were prominently higher in both LC3II/I and Beclin-1 in the OGD/R group compared with the NC group (LC3II/I: 1.44±0.05 vs. 0.37±0.03, Beclin-1/β-actin: 1.00±0.02 vs. 0.64±0.01, both P < 0.01); compared with the OGD/R group, the protein expression of both LC3II/I and Beclin-1 in the HW group cells were notably lower (LC3II/I: 0.54±0.02 vs. 1.44±0.05, Beclin-1/β-actin: 0.83±0.07 vs. 1.00±0.02, both P < 0.01).. Hydrogen-rich water has a significant protective effect on OGD/R-causing HT22 cell injury, and the mechanism may be related to the inhibition of autophagy.. The prevalence of delirium in ICU patients is over 50%, with hypoactive delirium being the most common. Age, APACHE score at ICU admission, neurological disease, sepsis and duration of mechanical ventilation were all independent risk factors for the development of delirium in ICU patients. More than half of patients with delirium were still delirious when they discharged from the ICU.. For individuals ≥75 years, plasma Aβ42 and P-tau181 might not be associated with cognitive impairment, and MRI parameters, including PVWMH, LVBI and cortical atrophy, are related to CI. The cognitive statuses of people over 75 years old were used as the endpoint event in this study. Therefore, it can be considered that these MRI markers might have more important clinical significance for early assessment and dynamic observation, but more studies are still needed to verify this hypothesis.. We recommend using the Art/Zn complex owing to its moderate inhibitory and antiviral effects against the SARS-CoV-2 with a low cytotoxic effect on host (Vero E6) cells. We suggest conducting further prospective studies to investigate the biological effects of Art/Zn in animal models at different concentrations for testing its clinical efficacy and safety in inhibiting SARS-CoV-2 activities.. The R/T sequence resulted in a significantly longer OS and PFS and improved disease control compared with the reverse sequence. R and T given not sequentially have similar impacts on survival. More data are needed to define the best sequence and to explore the efficacy of sequential (T/R or R/T) treatment combined with molecular-targeted drugs.

Topics: Actin Cytoskeleton; Actins; Adaptor Proteins, Signal Transducing; Adenocarcinoma; Adenosine Triphosphate; Adsorption; Adult; Africa, Eastern; Aged; Air Pollutants; Air Pollution; Air Pollution, Indoor; Alcohol Drinking; Allergens; Alzheimer Disease; Amyotrophic Lateral Sclerosis; Animals; Anti-Bacterial Agents; Antibodies; Antibodies, Immobilized; Antigen Presentation; Antigens, CD; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Antioxidants; Apoptosis; Aptamers, Nucleotide; Asthma; Asthma, Exercise-Induced; Atrophy; Autophagy; Azoospermia; Bacillus cereus; Bacterial Infections; Beclin-1; Bile Duct Neoplasms; Bile Ducts, Intrahepatic; Biofouling; Biological Monitoring; Biomarkers; Biomarkers, Tumor; Biosensing Techniques; Blastocyst; Bone Neoplasms; Bone Regeneration; Bronchoconstriction; Burkitt Lymphoma; C9orf72 Protein; Campylobacter; Campylobacter Infections; Campylobacter jejuni; Carcinogenesis; Carcinoma, Hepatocellular; Carcinoma, Pancreatic Ductal; Carcinoma, Squamous Cell; Cardiomyopathies; Caregivers; Carmine; Case-Control Studies; Catalysis; Cattle; Cause of Death; CCAAT-Enhancer-Binding Protein-alpha; CD8-Positive T-Lymphocytes; Cefepime; Cell Differentiation; Cell Line, Tumor; Cell Nucleus; Cell Transdifferentiation; Chelating Agents; Chemical and Drug Induced Liver Injury, Chronic; Chemoradiotherapy, Adjuvant; Child; Child, Preschool; China; Chlorquinaldol; Cholangiocarcinoma; Cholera; Chromatin; Clinical Trials as Topic; Cognitive Dysfunction; Cohort Studies; Colonic Neoplasms; Colorectal Neoplasms; Colorimetry; Cooking; Coordination Complexes; COVID-19; Creatinine; CRISPR-Cas Systems; Critical Care; Critical Illness; Cross-Sectional Studies; Cryopreservation; Cryoprotective Agents; Cysteine; Cytokines; Device Removal; Diet; Diet, High-Fat; Diet, Mediterranean; Dietary Supplements; Dimethyl Sulfoxide; Dipeptides; Disease Models, Animal; Dithiothreitol; DNA; DNA Repeat Expansion; DNA, Bacterial; DNA, Complementary; Dopamine; Electrochemical Techniques; Electrodes; Endocannabinoids; Environmental Exposure; Environmental Monitoring; Environmental Pollutants; Enzyme-Linked Immunosorbent Assay; Erlotinib Hydrochloride; Escherichia coli; Escherichia coli O157; Esophageal Neoplasms; Esophagitis, Peptic; Ethylene Glycol; Europium; Exanthema; Fallopian Tubes; Feces; Female; Fertilization in Vitro; Fluoresceins; Fluorescent Dyes; Follicle Stimulating Hormone; Follow-Up Studies; Food Microbiology; Forced Expiratory Volume; Forkhead Transcription Factors; Frontotemporal Dementia; G-Quadruplexes; Galactose; Gastroenteritis; Gastrointestinal Diseases; Gastrointestinal Microbiome; Gastrointestinal Neoplasms; Gastrointestinal Tract; Gene Frequency; Genetic Association Studies; Genetic Predisposition to Disease; Genital Neoplasms, Female; Genome-Wide Association Study; Genome, Viral; Genomics; Genotype; Glucose; Glutathione; Glycerol; Gold; Graphite; GTPase-Activating Proteins; Heat-Shock Proteins; Heme Oxygenase-1; Hepacivirus; Hepatitis C; Hepatocytes; Histamine; Histocompatibility Antigens Class II; Hoarseness; Hospice and Palliative Care Nursing; Humans; Hydrogen; Hydrogen Peroxide; Hydrogen Sulfide; Hydroxybenzoates; Hydroxyl Radical; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Hyperthermia, Induced; Hysteroscopy; Immunoassay; Indigo Carmine; Inflammation; Inflammatory Bowel Diseases; Insulin Resistance; Intensive Care Units; Interleukin-11; Interleukin-6; Interleukins; Iodine Radioisotopes; Iran; Iridium; Islets of Langerhans; Kinetics; Lactation; Lactobacillus; Lactobacillus plantarum; Lamins; Latin America; Lead; Lectins; Leukopenia; Ligands; Limit of Detection; Lipopolysaccharides; Lipoprotein Lipase; Liver; Liver Cirrhosis; Liver Neoplasms; Lolium; Luminescent Measurements; Luminol; Lung; Luteinizing Hormone; Macrophages; Magnetic Phenomena; Magnetic Resonance Imaging; Male; Malnutrition; Maltose; Manganese Compounds; Maternal Nutritional Physiological Phenomena; Melatonin; Metabolic Engineering; Metal Nanoparticles; Metallocenes; Metaplasia; Methicillin-Resistant Staphylococcus aureus; Methylation; Mevalonic Acid; Mexico; Mice; Mice, Inbred C57BL; Mice, Transgenic; Microbial Sensitivity Tests; Microbiota; MicroRNAs; Milk; Mitomycin; Molecular Diagnostic Techniques; Molecular Docking Simulation; Monte Carlo Method; Moringa oleifera; Multiple Sclerosis; Muscle Strength; Muscle, Skeletal; Nanocomposites; Nanotubes, Carbon; Neoadjuvant Therapy; Neoplasms; Neurodegenerative Diseases; Neurotransmitter Agents; NF-E2-Related Factor 2; Nickel; Nitrogen Dioxide; Non-alcoholic Fatty Liver Disease; Nucleic Acid Amplification Techniques; Nucleic Acid Hybridization; Nucleocapsid Proteins; Nutritional Status; Obesity; Osteogenesis; Osteosarcoma; Oxidation-Reduction; Oxides; Oxygen; Oxyquinoline; Pain; Palliative Care; Pancreatic Neoplasms; Pandemics; Particulate Matter; Peroxidase; Peroxidases; Phagocytosis; Phaseolus; Photothermal Therapy; Point-of-Care Systems; Polyethyleneimine; Polymers; Polymorphism, Single Nucleotide; Polysomnography; Postoperative Complications; Pregnancy; Pregnant Women; Prenatal Exposure Delayed Effects; Prevalence; Printing, Three-Dimensional; Probability; Probiotics; Prognosis; Prophages; Prospective Studies; Proteomics; Proto-Oncogene Proteins; Pseudomonas aeruginosa; Pseudomonas putida; Pulmonary Disease, Chronic Obstructive; Pulmonary Embolism; Pyridines; Pyrroles; Quality of Life; Quinolones; Rabbits; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Real-Time Polymerase Chain Reaction; Receptors, Histamine; Receptors, Histamine H2; Recombinases; Rectal Neoplasms; Reperfusion Injury; Respiration; Respiratory Function Tests; Respiratory Rate; Respiratory Sounds; Retrospective Studies; rho GTP-Binding Proteins; Risk Assessment; Risk Factors; RNA; RNA, Messenger; RNA, Ribosomal, 16S; Robotic Surgical Procedures; Running; Rural Population; Saccharomyces cerevisiae; Salpingectomy; Sarcopenia; SARS-CoV-2; Seeds; Semen; Sensitivity and Specificity; Sepsis; Shock, Septic; Signal Transduction; Silicon Dioxide; Silver; Sirtuin 1; Skin Neoplasms; Sleep Apnea, Obstructive; Soil; Spain; Spectrum Analysis, Raman; Sperm Retrieval; Spermatozoa; Spirometry; Staphylococcus aureus; STAT3 Transcription Factor; Stereoisomerism; Sterilization, Tubal; Stroke Volume; Sulfadiazine; Sulfites; Superoxide Dismutase; Surface Plasmon Resonance; tau Proteins; Testis; Testosterone; Thioredoxin-Disulfide Reductase; Thyroid Neoplasms; Thyroidectomy; Trans-Activators; Transcription Factor AP-1; Treatment Outcome; Triazoles; Triclosan; Trifluridine; Tumor Microenvironment; Tumor Necrosis Factor-alpha; United States; Uracil; Vagina; Vegetables; Ventricular Function, Left; Ventricular Pressure; Vibrio cholerae; Vietnam; Virulence; Vital Capacity; Vitrification; Walking; Water; Water Pollutants, Radioactive; Whole Genome Sequencing; Wind; YAP-Signaling Proteins; Zeolites; Zinc Oxide

Testicular torsion/detorsion-induced ischemia/reperfusion injury is partly due to the overgeneration of reactive oxygen species. Baicalein, a main bioactive constituent derived from the dried root of

Topics: Animals; Antioxidants; Ischemia; Male; Malondialdehyde; NADPH Oxidases; Peroxidase; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Reperfusion Injury; Spermatic Cord Torsion; Testis; Tumor Necrosis Factor-alpha

The most effective way of treating liver cancer is surgical resection, which usually requires blocking the hepatic portal circulation, and may result in hepatic ischemia-reperfusion injury (HIRI). It is of paramount importance to control HIRI for liver cancer surgical resection. In this study, a 70% ischemia-reperfusion (I/R) model of rat liver was established, and the protective effect and mechanism of limb ischemic post-conditioning (LIPOC) on HIRI was investigated. We show that LIPOC has a protective effect on hepatic ischemia-reperfusion injury in rats, which reduces the elimination of superoxide dismutase, thereby increasing oxygen free radical scavenging, decreasing lipid peroxidation, inhibiting neutrophil aggregation, as well as reducing TNFα, IL1β, and other inflammatory cytokines. In addition, LIPOC inhibited the apoptosis of hepatocytes induced by I/R injury, and decreased the Bax/Bcl-2 ratio. Furthermore, LIPOC promoted the phosphorylation of Akt and ERK1/2. The use of PI3K inhibitor LY294002 and ERK1/2 blocker PD98059 inhibited the phosphorylation of Akt and ERK1/2 caused by LIPOC and abolished the injury protection of liver I/R. Moreover, through 16 cases of hepatocellular carcinoma resections, we found that short-term LIPOC treatment significantly suppressed the elevated alanine aminotransferase, aspartic transaminase, and total bilirubin in the early post-operation of liver resection, and reduced reperfusion injury to the ischemic liver. In summary, our study demonstrates that LIPOC could be an effective method for HIRI in the clinical implementation of liver resection and uncovers the potential mechanism of LIPOC in the protective effects of HIRI.

Topics: Adult; Aged; Alanine Transaminase; Animals; Apoptosis; Blotting, Western; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Female; Humans; In Situ Nick-End Labeling; Ischemia; Ischemic Postconditioning; Liver Neoplasms; Male; Malondialdehyde; MAP Kinase Signaling System; Middle Aged; Peroxidase; Phosphatidylinositol 3-Kinases; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase

Sildenafil and nitroglycerin (GTN) are effective pharmacological preconditioning agents, protecting from the adverse effects of ischemia and reperfusion (I/R). The objective of the present study was to determine whether repeated, daily administration of sildenafil or GTN provides sustained preconditioning from I/R in the human forearm vasculature. Thirty-six healthy volunteers participated in this investigator-blind, randomized, placebo-controlled trial. Subjects received transdermal GTN (0.6 mg/h, 2 h/day), sildenafil (50 mg once daily), or placebo. Twenty-four hours after the first dose of medication, subjects underwent an assessment of flow-mediated dilation (FMD) before and after I/R (15 min of upper arm ischemia followed by 15 min of reperfusion). Subjects continued their study medication for 7 days, at which point FMD measurements were repeated before and after I/R. Venous blood samples were obtained for the determination of myeloperoxidase, P-selectin, and myoglobin before and after each I/R episode. Twenty-four hours after the first dose, both sildenafil and GTN (but not placebo) provided protection from the adverse effects of I/R. After 7 days of repeated daily doses and 24 h after the last dose, FMD was significantly blunted after I/R in placebo- and GTN-treated groups. In contrast, repeated daily administration of sildenafil provided continued protection from the adverse effects of I/R on endothelial function. There was no significant change in plasma levels of myeloperoxidase, P-selectin, or myoglobin at any time point. In conclusion, the present study establishes, for the first time in humans, that sildenafil, but not GTN, provides sustained pharmacological preconditioning of the endothelium and protection from adverse I/R effects on vascular function.

Topics: Administration, Cutaneous; Adolescent; Adult; Biomarkers; Drug Administration Schedule; Endothelium, Vascular; Forearm; Healthy Volunteers; Hemodynamics; Humans; Male; Myoglobin; Nitroglycerin; P-Selectin; Peroxidase; Piperazines; Purines; Radial Artery; Reperfusion Injury; Sildenafil Citrate; Sulfones; Time Factors; Treatment Outcome; Vasodilator Agents; Young Adult

To investigate the effects of exercise preconditioning on oxidative injury in the intestinal tissue of rats.. Sixty male Wistar rats were randomly divided into six groups as sham (n = 10), ischemia-reperfusion (n = 10), exercise (n = 10), exercise plus ischemia-reperfusion (n = 10), ischemic preconditioning (n = 10), and ischemic preconditioning plus ischemia-reperfusion groups (n = 10). Tissue levels of malondialdehyde and activities of myeloperoxidase and superoxide dismutase, and serum levels of tumor necrosis factor-alpha and interleukin-6 were measured. Intestinal tissue histopathology was also evaluated by light microscopy.. Tumor necrosis factor-alpha concentrations significantly decreased in the exercise group compared to the sham group (p < 0.05). Myeloperoxidase activity significantly increased and superoxide dismutase activity significantly decreased in ischemia-reperfusion group compared to the sham group (p < 0.05). Superoxide dismutase activity in the ischemic preconditioning and ischemic preconditioning plus ischemia-reperfusion groups were significantly higher compared to the ischemia-reperfusion and exercise groups (p < 0.05). Histopathologically, intestinal injury significantly attenuated in the exercise plus ischemia-reperfusion group compared to the ischemia-reperfusion group.. The results of the present study indicate that exercise training seems to have a protective role against intestinal ischemia-reperfusion injury (Tab. 3, Fig. 1, Ref. 35).

Topics: Animals; Humans; Interleukin-6; Intestines; Ischemic Preconditioning; Male; Malondialdehyde; Oxidative Stress; Peroxidase; Physical Conditioning, Animal; Random Allocation; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase; Tumor Necrosis Factor-alpha

The prophylactic administration of inhaled nitric oxide (NO) during reperfusion after lung transplantation has been shown to reduce neutrophil-induced injury in animal models. There remain questions regarding efficacy in the clinical setting and concerns regarding increased free radical injury. We sought to assess the efficacy of NO in reducing neutrophil infiltration and associated injury if administered from the very onset of reperfusion in clinical lung transplantation.. Twenty bilateral sequential lung transplant recipients were randomized to receive 20-ppm inhaled NO (NO group) or a standard anesthetic gas mixture (control group) from the onset of ventilation. Bronchoalveolar lavage was performed immediately prior to implantation and after 30 minutes of reperfusion and analyzed for inflammatory cytokine levels and free radical surrogates. Primary graft dysfunction (PGD) scoring was performed prospectively for 72 hours post-transplant.. The prophylactic administration of NO during the first 30 minutes of reperfusion had no statistically significant effect on the development of Grade II to III PGD (5 of 10 in NO group and 7 of 10 in control group, p = 0.36) or gas exchange (area under the curve: 429 +/- 296 vs 336 +/- 306; p = 0.64) in the NO and control groups, respectively. Pulmonary neutrophil sequestration, as measured by the transpulmonary arteriovenous neutrophil difference, was not influenced by the administration of NO. Prophylactic NO did not significantly alter the concentration of interleukin-8, myeloperoxidase or nitrotyrosine during transplantation.. This study could not demonstrate a significant effect of inhaled NO during the first 30 minutes of reperfusion in the prevention of neutrophil injury and primary graft dysfunction after lung transplantation.

Topics: Administration, Inhalation; Adult; Bronchoalveolar Lavage Fluid; Female; Free Radical Scavengers; Free Radicals; Graft Rejection; Humans; Interleukin-8; Lung; Lung Transplantation; Male; Middle Aged; Neutrophils; Nitric Oxide; Peroxidase; Reperfusion Injury; Tyrosine

Abdominal aortic aneurysmectomy (AAAectomy) results in a general ischemia-reperfusion syndrome accompanied by an acute rise in pulmonary artery pressure (PAP). We examined whether ulinastatin, a urinary trypsin inhibitor, prevents ischemia-reperfusion injury and increase in PAP after aortic unclamping (XU) during AAAectomy.. Prospective study.. Public, university-affiliated hospital.. Sixteen patients (11 males and 5 females) scheduled for AAAectomy.. The patients received 300000 IU of ulinastatin intravenously before XU (n = 8) or no additional treatment (n = 8) (control). Heart rate, central venous pressure, PAP, pulmonary arterial wedge pressure, arterial pressure, mixed venous oxygen saturation (Sv(O2)), and cardiac output were monitored. Arterial and mixed venous blood samples were analyzed for pH, Pa(CO2), Pa(O2), hemoglobin, and oxygen saturation, and the physiological shunt function (Qs/Qt) were calculated. Plasma concentrations of malondialdehyde, myeloperoxidase, granulocyte elastase, alpha1-antitrypsine, and thromboxane B2 and the stable hydrolysis products of thromboxane A2 were measured. Measurements were conducted before aortic crossclamping (XC) (baseline) and at 10, 30, and 60 minutes after XU.. A significant increase in PAP was observed 10 minutes after XU in the control group but not in the ulinastatin group. At 60 minutes after XU, Qs/Qt values had increased in the control group but had decreased in the ulinastatin group. There were no significant changes in malondialdehyde, thromboxane B2, granulocyte elastase, and alpha1-antitrypsine levels after XU in either group. A significant decrease in the plasma level of myeloperoxidase after XU was found in both groups.. The present study demonstrated that ulinastatin prevents increase in PAP and shunting after XU during AAAectomy.

Topics: Aged; alpha 1-Antitrypsin; Aorta; Aortic Aneurysm, Abdominal; Blood Pressure; Constriction; Female; Glycoproteins; Hemodynamics; Humans; Infusions, Intravenous; Intraoperative Period; Leukocyte Elastase; Male; Malondialdehyde; Peroxidase; Pulmonary Artery; Reperfusion Injury; Thromboxane B2; Trypsin Inhibitors

Temporary vascular clampage (Pringle maneuver) during liver surgery can cause ischemia-reperfusion injury. In this process, activation of polymorphonuclear leukocytes (PMNLs) might play a major role. Thus, we investigated the effects of hepatic ischemic preconditioning on PMNL functions.. Prospective randomized study. Patients who underwent partial liver resection were randomly assigned to 3 groups: group 1 without Pringle maneuver; group 2 with Pringle maneuver, and group 3 with ischemic preconditioning using 10 minutes of ischemia and 10 minutes of reperfusion prior to Pringle maneuver for resection.. University hospital, Munich, Germany.. Seventy-five patients underwent hepatic surgery mostly owing to metastasis.. Perioperative factors for PMNL activation, inflammation, and postoperative hepatocellular integrity.. Ischemia-reperfusion of the human liver (mean +/- SD time to perform the Pringle maneuver, 35.5 +/- 2.6 minutes) caused (1) a decrease in the number of circulating PMNLs, (2) their intrahepatic sequestration, (3) their systemic activation, and (4) a significant correlation between the degree of their postischemic activation and the postoperative rise in liver enzyme serum levels. In parallel, cytokines with proinflammatory and chemotactic properties were released reaching the highest values when stimulation of PMNLs was most pronounced. When ischemic preconditioning preceded the Pringle maneuver, activation of PMNLs and cytokine plasma levels was reduced as evidenced by the attenuation of superoxide anion production, beta(2)-integrin up-regulation, and interleukin 8 serum concentrations, followed by a significant reduction in serum alanine aminotransferase levels on the first and second postoperative days.. These results demonstrate in humans that ischemic preconditioning reduces activation of PMNLs elicited by the Pringle maneuver. The down-regulation of potentially cytotoxic functions of PMNLs might be one of yet unknown important pathways that altogether mediate protection by ischemic preconditioning.

Topics: CD18 Antigens; Female; Hepatectomy; Humans; Interleukin-8; Ischemic Preconditioning; Liver Neoplasms; Male; Middle Aged; Neutrophil Activation; Neutrophils; Peroxidase; Prospective Studies; Reperfusion Injury

Complement activation contributes to ischemia-reperfusion injury. Patients undergoing thoracoabdominal aortic aneurysm (TAAA) repair suffer extensive ischemia-reperfusion and considerable systemic inflammation.. The degree and mechanism of complement activation and its role in inflammation were investigated in 19 patients undergoing TAAA repair. Patients undergoing open infrarenal aortic surgery (n=5) or endovascular descending aortic aneurysm repair (n=6) served as control subjects. Substantial complement activation was seen in TAAA patients but not in controls. C1rs-C1-inhibitor complexes increased moderately, whereas C4bc, C3bBbP, C3bc, and the terminal SC5b-9 complex (TCC) increased markedly after reperfusion, reaching a maximum 8 hours after reperfusion. Interleukin (IL)-1beta, tumor necrosis factor alpha (TNF-alpha), and IL-8 increased significantly in TAAA patients but not in controls, peaking at 24 hours postoperatively and correlating closely with the degree of complement activation. IL-6 and IL-10 increased to a maximum 8 hours after reperfusion in the TAAA patients, were not correlated with complement activation, and increased moderately in the control subjects. Myeloperoxidase and lactoferrin increased markedly before reperfusion in all groups, whereas sICAM-1, sP-selectin, and sE-selectin were unchanged. No increase was observed in complement activation products, IL-1beta, TNF-alpha, or IL-8 in a mannose-binding lectin (MBL)-deficient TAAA patient, whereas IL-6, IL-10, myeloperoxidase, and lactoferrin increased as in the controls. Two other MBL-deficient TAAA patients receiving plasma attained significant MBL levels and showed complement and cytokine patterns identical to the MBL-sufficient TAAA patients.. The data suggest that complement activation during TAAA repair is MBL mediated, amplified through the alternative pathway, and responsible in part for the inflammatory response.

Topics: Aged; Aged, 80 and over; Aortic Aneurysm, Abdominal; Aortic Aneurysm, Thoracic; Cell Adhesion Molecules; Chemokines; Complement Activation; Cytokines; Female; Humans; Inflammation; Lactoferrin; Male; Mannose-Binding Lectin; Middle Aged; Neutrophil Activation; Peroxidase; Plasma; Prospective Studies; Reperfusion Injury; Vascular Surgical Procedures

to elicit whether pre-treatment with pravastatin will prevent or ameliorate the acute lung injury that occurs following lower torso ischaemia-reperfusion (IR) in an experimental animal model.. male Sprague-Dawley rats were randomised into three groups (n=7/group). The control group underwent a sham laparotomy and aortic dissection. The second group underwent infrarenal aortic cross clamping for 30 min followed by reperfusion for 120 min. The third group pre-treated with pravastatin sodium (0.4 mg/kg/day over 5 days) were again subjected to an ischaemia-reperfusion (IR) injury. The parameters used to assess lung injury included: Wet to dry lung weight ratio (W:D), myeloperoxidase activity (MPO), protein concentration (BALprot) and neutrophil count (BAL PMN) of bronchoaveolar lavage fluid. Western blotting was used to determine the expression of constitutive endothelial nitric oxide synthase (ecNOS) within lung tissue.. IR causes an acute lung injury as indicated by statistically significant differences in W:D lung weight ratios, MPO activity, neutrophil count and BALprotein concentration in the IR group over that of controls. Pre-treatment with pravastatin attenuated this neutrophil infiltration and microvascular leakage. The pravastatin group showed a marked increased expression of ecNOS over that of the IR group and controls.. this data indicates that pre-treatment with pravastatin protects against ischaemia-reperfusion induced lung injury in an experimental animal model. We believe that its mechanism of action involves an upregulation of ecNOS, which increases basal expression of nitric oxide providing protective effects on the pulmonary circulation against microvascular injury.

Topics: Analysis of Variance; Animals; Blotting, Western; Bronchoalveolar Lavage Fluid; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Lung; Male; Neutrophils; Nitric Oxide Synthase; Peroxidase; Pravastatin; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Up-Regulation

To determine the effects of the 21-aminosteroid, U-74389G, on reperfusion of the equine jejunum, using total (TVO) and partial (PVO) vascular occlusion during the ischemic period.. TVO: 16 healthy horses were randomly allotted to 3 groups-4 horses received the vehicle alone, 6 horses received a low dosage (3 mg/kg o body weight), and 6 horses a high dosage (10 mg/kg) of U-7438G. PVO: 10 healthy horses were randomly allotted to 2 groups--5 horses received the vehicle alone, and 5 horses received the low dosage (3 mg/kg) of U-74389G.. TVO was induced for 1 hour followed by 2 hours of reperfusion. During PVO, blood flow was reduced to 20% of baseline for 2 hours, followed by 2 hours of reperfusion. For both models, either the vehicle alone or the drug was given 15 minutes prior to reperfusion. Samples were obtained before, during, and after ischemia for determination of myeloperoxidase (MPO) activity, malondealdehyde (MDA) concentration, concentration of conjugated dienes (PVO experiment only), and morphometric analysis.. TVO: tissue concentration of MDA and MPO activity were not altered in any group by ischemia or reperfusion. During ischemia, mucosal volume and surface area were reduced. After reperfusion, no further reduction occurred. After initial decrease in submucosal volume during ischemia, there was a significant increase after reperfusion in the vehicle-only group (P < 0.05). PVO: there were no alterations in the concentration of either MDA or conjugated dienes. There was significant increase in the activity of MPO during ischemia and reperfusion (P < 0.05). These effects were similar for the vehicle-only and drug groups. During ischemia, there was a significant decrease in mucosal surface area and volume (P < 0.05), that was continued during reperfusion for the vehicle-only (P < 0.05). Submucosal volume increased during ischemia and reperfusion.. Reduced blood flow during ischemia (PVO group) caused continued loss in mucosal volume and surface area during reperfusion. At the dosage given, the 21-aminosteroid, U-74389G, was not effective in preventing continued reduction in mucosal volume and surface area after restoration of blood supply in the horses subjected to reduced blood flow.

Topics: Animals; Antioxidants; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Horse Diseases; Horses; Infusions, Intravenous; Intestinal Mucosa; Jejunum; Male; Malondialdehyde; Mesenteric Vascular Occlusion; Peroxidase; Pregnatrienes; Reperfusion Injury; Time Factors

Thirty horses were randomly assigned to 1 of 5 groups. All horses were anesthetized and subjected to ventral midline celiotomy, then the large colon was exteriorized and instrumented. Colonic arterial blood flow was reduced to 20% of baseline (BL) and was maintained for 3 hours. Colonic blood flow was then restored, and the colon was reperfused for an additional 3 hours. One of 5 drug solutions was administered via the jugular vein 30 minutes prior to colonic reperfusion: group 1, 0.9% NaCl; group 2, dimethyl sulfoxide: 1 g/kg of body weight; group 3, allopurinol: 25 mg/kg; group 4, 21-aminosteroid U-74389G: 10 mg/kg; and group 5, manganese chloride (MnCl2): 10 mg/kg. Hemodynamic variables were monitored and recorded at 30-minutes intervals. Systemic arterial, systemic venous (SV), and colonic venous (CV) blood samples were collected for measurement of blood gas tensions, oximetry, lactate concentration, PCV, and plasma total protein concentration. The eicosanoids, 6-keto prostaglandin F1 alpha, prostaglandin E2, and thromboxane B2, were measured in CV blood, and endotoxin was measured in CV and SV blood. Full-thickness biopsy specimens were harvested from the left ventral colon for histologic evaluation and determination of wet weight-to-dry weight ratios (WW:DW). Data were analyzed, using two-way ANOVA for repeated measures, and statistical significance was set at P < 0.05. Heart rate, mean arterial pressure, and cardiac output increased with MnCl2 infusion; heart rate and cardiac output remained increased throughout the study, but mean arterial pressure returned to BL values within 30 minutes after completion of MnCl2 infusion. Other drug-induced changes were not significant. There were significant increases in mean pulmonary artery and mean right atrial pressures at 2 and 2.5 hours in horses of all groups, but other changes across time or differences among groups were not observed. Mean pulmonary artery pressure remained increased through 6 hours in all groups, but mean right atrial pressure had returned to BL values at 3 hours. Mean colonic arterial pressure was significantly decreased at 30 minutes of ischemia and remained decreased through 6 hours; however, by 3.25 hours it was significantly higher than the value at 3 hours of ischemia. Colonic arterial resistance decreased during ischemia and remained decreased throughout reperfusion in all groups; there were no differences among groups for colonic arterial resistance.(ABSTRACT TRUNCATED AT 400 WO

Topics: Allopurinol; Analysis of Variance; Animals; Antioxidants; Chlorides; Colon; Dimethyl Sulfoxide; Endotoxins; Hemodynamics; Horses; Manganese Compounds; Peroxidase; Pregnatrienes; Reperfusion Injury

Histomorphologic/morphometric evaluation, leukocyte scintigraphy, and myeloperoxidase activity were used to determine whether neutrophils accumulate in the large colon of horses during low-flow ischemia and reperfusion. Twenty-four adult horses were assigned to 1 of 3 groups: group 1, sham-operated (n = 6); group 2, 6 hours of ischemia (n = 9); and group 3, 3 hours of ischemia and 3 hours of reperfusion (n = 9). Low-flow ischemia of the large colon was induced in horses of groups 2 and 3 by reducing colonic arterial blood flow to 20% of baseline. Radiolabeled (99mTc) autogenous neutrophils were injected at 175 minutes, which corresponded to 5 minutes prior to reperfusion in group-3 horses. Full-thickness biopsy specimens of the left ventral colon were collected at baseline and at 30-minute intervals for 6 hours; a portion of the biopsy specimen was placed in formalin for histologic examination, and the remainder was used to measure mucosal radioactivity and myeloperoxidase activity. There were no differences in baseline mucosal neutrophil index, mucosal neutrophil numbers, submucosal venular neutrophil numbers, mucosal radioactivity, or mucosal myeloperoxidase activity among groups, or over time in group-1 horses. Neutrophils accumulated in the colonic mucosa during ischemia and further increased at reperfusion, as indicated by neutrophil index (morphology) and mucosal neutrophil numbers (morphometry); mucosal neutrophil index was significantly (P < 0.05) greater in group-3 horses during reperfusion than at the corresponding periods of ischemia in group-2 horses. Neutrophil numbers were significantly (P < 0.05) increased in submucosal venules at 10 minutes of reperfusion in group-3 horses and were significantly (P < 0.05) greater in group-3 than in group-2 horses during the interval from 3 to 6 hours. Mucosal radioactivity significantly (P < 0.05) increased at reperfusion in group-3 horses; there was a trend (P = 0.076) toward greater mucosal radioactivity in group-3, compared with group-2 horses, throughout the 3- to 6-hour interval. There were no differences in mucosal myeloperoxidase activity among or within any of the 3 groups over time. Neutrophils accumulated in the large colon of horses during low-flow ischemia and reperfusion. Neutrophil infiltration was detected by histologic examination and leukocyte scintigraphy, but not by measurement of myeloperoxidase activity. The accumulation of neutrophils during ischemia and the further neutrophil infilt

Topics: Animals; Colitis, Ischemic; Colon; Female; Horse Diseases; Horses; Intestinal Mucosa; Ischemia; Male; Neutrophils; Peroxidase; Radionuclide Imaging; Reperfusion Injury

Sixteen horses were allotted at random to 3 groups: vehicle only; low dosage (vehicle and 3 mg of U-74389G/kg of body weight); high dosage (vehicle and 10 mg of U-74389G/kg). These solutions were given prior to reperfusion. The ascending colon was subjected to 2 hours of ischemia followed by 2 hours of reperfusion. Before, during, and after ischemia, full-thickness colonic tissue biopsy specimens were obtained for measurement of malondealdehyde (MDA) concentration and myeloperoxidase activity and for morphologic evaluation. Although increases were not significant, MDA concentration and myeloperoxidase activity increased during ischemia and reperfusion. Administration of U-74389G did not have significant effects on MDA concentration and myeloperoxidase activity. However, the lower dosage tended (P = 0.08) to reduce myeloperoxidase activity at 30 and 60 minutes of reperfusion. In horses of the vehicle-only group, ischemia induced a decrease in mucosal surface area that was continued into the reperfusion period (P < or = 0.05). Administration of U-74389G at both dosages (3 and 10 mg/kg) prevented the reperfusion-induced reduction in mucosal surface area, which was significant at 60 minutes (high dosage; P = 0.05) and 90 minutes (low and high dosages; P = 0.02). After initial reduction in horses of all groups, mucosal volume increased for the initial 60 minutes of reperfusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Analysis of Variance; Animals; Antioxidants; Biopsy; Colon; Female; Horse Diseases; Horses; Ischemia; Male; Malondialdehyde; Peroxidase; Pregnatrienes; Reperfusion Injury; Time Factors

We previously demonstrated that prehabilitation by running on a treadmill leads to improved survival after gut ischemia reperfusion (I/R) in mice. The purpose of this research was to examine whether prehabilitation attenuates inflammatory responses after gut I/R in mice.. Male C57BL/6J mice (n = 92) were assigned to the sedentary (n = 46) or the exercise (n = 46) group. The exercise group ran on a treadmill for 4 wk, while the sedentary mice did not exercise. After the 4-week pretreatment, all mice underwent gut I/R and the blood, urine, small intestine, lung, liver, and gastrocnemius were harvested prior to ischemia or at 0, 3, 6, or 24 h after reperfusion. Histologically demonstrated organ damage, cytokine levels in the blood, gut and gastrocnemius, myeloperoxidase activity in the gut, 8-hydroxy-2'-deoxyguanosine levels in urine and the gut, and adenosine triphosphate (ATP) and ATP + ADP + adenosine monophosphate levels in the gut and gastrocnemius were evaluated.. The treadmill exercise reduced gut and lung injuries at 3 h and liver injury at 6 h after reperfusion. Running on the treadmill also decreased proinflammatory cytokine levels in the blood at 6 h, gut at 3 h and gastrocnemius at 6 h after reperfusion, myeloperoxidase activity in the gut prior to ischemia, and 6 h after reperfusion and the urinary 8-hydroxy-2'-deoxyguanosine level at 24 h after reperfusion, while ATP levels in exercised mice prior to ischemia and 3 h after reperfusion were increased in the intestine as compared to the levels in sedentary mice.. Prehabilitation with treadmill exercise reduces inflammatory responses after gut I/R and may exert protective actions against gut I/R.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adenosine Triphosphate; Animals; Antioxidants; Cytokines; Ischemia; Male; Mice; Mice, Inbred C57BL; Peroxidase; Physical Conditioning, Animal; Preoperative Exercise; Reperfusion Injury

Remote ischaemic conditioning (RIC) has been shown to reduce ischaemia-reperfusion injury(IRI) in multiple organ systems. IRI is seen in multiple bowel pathologies in the newborn, including NEC. We investigated the potential of RIC as a novel therapy for various intestinal pathologies in the newborn.. We used an established intestinal IRI model in rat pups which results in similar intestinal injury to necrotising enterocolitis (NEC). Animals were randomly allocated to IRI only(n = 14), IRI + RIC(n = 13) or sham laparotomy(n = 10). The macroscopic extent of intestinal injury is reported as a percentage of total small bowel. Injury severity was measured using Chiu-Park scoring. Neutrophil infiltration/activation was assayed by myeloperoxidase activity. Immunohistochemistry was used to assess the expression of hypoxia-inducible factor alpha (HIF-1α). Data are median (interquartile range).. Animals that underwent RIC showed a decreased extent of macroscopic injury from 100%(85-100%) in the IRI only group to 58%(15-84%, p = 0.003) in the IRI + RIC group. Microscopic injury score was significantly lower in animals that underwent RIC compared to IRI alone (3.5[1.25-5] vs 5.5[4-6], p = 0.014). Intestinal myeloperoxidase activity in animals exposed to IRI was 3.4 mU/mg of tissue (2.5-3.7) and 2.1 mU/mg(1.5-2.8) in the IRI + RIC group(p = 0.047). HIF-1α expression showed a non-significant trend towards reduced expression in the IRI + RIC group.. RIC reduces the extent and severity of bowel injury in this animal model, supporting the hypothesis that RIC has therapeutic potential for intestinal diseases in the newborn.

Topics: Animals; Animals, Newborn; Ischemia; Ischemic Preconditioning; Peroxidase; Rats; Reperfusion Injury

Mildronate is a useful anti-ischemic agent and has antiinflammatory, antioxidant, and neuroprotective activities. The aim of this study is to investigate the potential neuroprotective effects of mildronate in the experimental rabbit spinal cord ischemia/reperfusion injury (SCIRI) model.. Rabbits were randomized into 5 groups of 8 animals as groups 1 (control), 2 (ischemia), 3 (vehicle), 4 (30 mg/kg methylprednisolone [MP]), and 5 (100 mg/kg mildronate). The control group underwent only laparotomy. The other groups have the spinal cord ischemia model by a 20-minute aortic occlusion just caudal to the renal artery. The malondialdehyde and catalase levels and caspase-3, myeloperoxidase, and xanthine oxidase activities were investigated. Neurologic, histopathologic, and ultrastructural evaluations were also performed.. The serum and tissue myeloperoxidase, malondialdehyde, and caspase-3 values of the ischemia and vehicle groups were statistically significantly higher than those of the MP and mildronate groups (P < 0.001). Serum and tissue catalase values of the ischemia and vehicle groups were statistically significantly lower than those of the control, MP, and mildronate groups (P < 0.001). The histopathologic evaluation showed a statistically significantly lower score in the mildronate and MP groups than in the ischemia and vehicle groups (P < 0.001). The modified Tarlov scores of the ischemia and vehicle groups were statistically significantly lower than those of the control, MP, and mildronate groups (P < 0.001).. This study presented the antiinflammatory, antioxidant, antiapoptotic, and neuroprotective effects of mildronate on SCIRI. Future studies will elucidate its possible use in clinical settings in SCIRI.

Topics: Animals; Antioxidants; Caspase 3; Catalase; Disease Models, Animal; Ischemia; Malondialdehyde; Methylprednisolone; Neuroprotective Agents; Peroxidase; Rabbits; Reperfusion Injury; Spinal Cord; Spinal Cord Ischemia

To investigate the effects of cerebrolysin on inflammation, oxidative stress, apoptosis, and neurologic recovery in the setting of an experimental rabbit model of spinal cord ischemia/reperfusion injury (SCIRI).. Rabbits were randomly divided into five groups: control, ischemia, vehicle, methylprednisolone (30 mg/kg), and cerebrolysin (5 ml/kg) group. The rabbits in the control group underwent only laparotomy; the other groups underwent spinal cord ischemia and reperfusion injury for 20 minutes. Neurologic examination after 24 hours was based on the Modified Tarlov scale. Myeloperoxidase activities, catalase and malondialdehyde levels, and caspase-3 concentrations were determined in serum and tissue samples. Serum xanthine oxidase levels were studied and histopathological and ultrastructural changes were examined.. After SCIRI, serum and tissue myeloperoxidase activities, malondialdehyde levels, caspase-3 concentrations, and serum xanthine oxidase activities were increased (p < 0.01?0.001). Catalase levels were significantly diminished (p < 0.001). Cerebrolysin treatment correlated with reduced myeloperoxidase and xanthine oxidase activities, malondialdehyde levels and caspase-3 concentrations; and with increased catalase levels (p < 0.001, for all). The cerebrolysin group showed improved histopathological, ultrastructural, and neurological outcomes.. For the first time in the literature, the current study reports anti-inflammatory, antioxidant, antiapoptotic, and neuroprotective effects of cerebrolysin in a SCIRI rabbit model.

Topics: Animals; Antioxidants; Caspase 3; Catalase; Malondialdehyde; Neuroprotective Agents; Peroxidase; Rabbits; Reperfusion Injury; Spinal Cord; Spinal Cord Ischemia; Xanthine Oxidase

Stroke is a leading cause of disability and death worldwide. Ivermectin is a broad-spectrum anti-parasitic agent with potential anti-bacterial, anti-viral, and anti-cancer effects. However, the effects of ivermectin on the brain are poorly described. This study examined the effects of ivermectin on cerebral ischemia-reperfusion (IR) in rats. A rat model of transient global IR was induced by bilateral carotid artery occlusion for 20 min. Rats received ivermectin (2 mg/kg/day, ip) one hour after inducing cerebral IR for three consecutive days at 24-h intervals. Next, we examined the effects of ivermectin on brain infarction, histopathology, malondialdehyde levels, myeloperoxidase activity, spatial learning and memory, and phospho-AMPK protein levels. The results showed that ivermectin reduced brain infarct size (P < 0.001) and histopathological changes such as cerebral leukocyte accumulation and edema (P < 0.05) compared to untreated rats with IR. Treatment with ivermectin also decreased myeloperoxidase activity (P < 0.01) and malondialdehyde levels (P < 0.05) while increasing AMPK activity (P < 0.001), memory, and learning compared to the untreated IR group. Overall, we show for the first time that ivermectin conferred neuroprotective effects in a rat model of cerebral IR. Our results indicate that three days of treatment with ivermectin reduced brain infarct size, lipid peroxidation, and myeloperoxidase activity and improved memory and learning in rats with cerebral IR. These effects likely occurred via AMPK-dependent mechanisms.

Topics: AMP-Activated Protein Kinases; Animals; Antioxidants; Brain Ischemia; Cerebral Infarction; Ischemic Attack, Transient; Ivermectin; Malondialdehyde; Neuroprotective Agents; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion; Reperfusion Injury

Dexpanthenol (DXP) reportedly protects tissues against oxidative damage in various inflammation models. This study aimed to evaluate its effects on oxidative stress, inflammation, apoptosis, and neurological recovery in an experimental rabbit spinal cord ischemia/reperfusion injury (SCIRI) model.. Rabbits were randomized into 5 groups of 8 animals each: group 1 (control), group 2 (ischemia), group 3 (vehicle), group 4 (methylprednisolone, 30 mg/kg), and group 5 (DXP, 500 mg/kg). The control group underwent laparotomy only, whereas other groups were subjected to spinal cord ischemia by aortic occlusion (just caudal to the 2 renal arteries) for 20 min. After 24 h, a modified Tarlov scale was employed to record neurological examination results. Malondialdehyde and caspase-3 levels and catalase and myeloperoxidase activities were analyzed in tissue and serum samples. Xanthine oxidase activity was measured in the serum. Histopathological and ultrastructural evaluations were also performed in the spinal cord.. After SCIRI, serum and tissue malondialdehyde and caspase-3 levels and myeloperoxidase and serum xanthine oxidase activities were increased (P < 0.05-0.001). However, serum and tissue catalase activity decreased significantly (P < 0.001). DXP treatment was associated with lower malondialdehyde and caspase-3 levels and reduced myeloperoxidase and xanthine oxidase activities but increased catalase activity (P < 0.05-0.001). Furthermore, DXP was associated with better histopathological, ultrastructural, and neurological outcome scores.. This study was the first to evaluate antioxidant, anti-inflammatory, antiapoptotic, and neuroprotective effects of DXP on SCIRI. Further experimental and clinical investigations are warranted to confirm that DXP can be administered to treat SCIRI.

Topics: Animals; Antioxidants; Caspase 3; Catalase; Disease Models, Animal; Inflammation; Malondialdehyde; Neuroprotective Agents; Peroxidase; Rabbits; Reperfusion Injury; Spinal Cord; Spinal Cord Ischemia; Xanthine Oxidase

Intestinal ischemia-reperfusion (I/R) injury is a severe disease associated with high mortality. Stimulator of interferon genes (STING) is an intracellular protein that is activated by cytosolic DNA and is implicated in I/R injury, resulting in transcription of type I interferons (IFN-α and IFN-β) and other proinflammatory molecules. Extracellular cold-inducible RNA-binding protein (eCIRP), a damage-associated molecular pattern, induces STING activation. H151 is a small molecule inhibitor of STING that has not yet been studied as a potential therapeutic. We hypothesize that H151 reduces inflammation, tissue injury, and mortality after intestinal I/R. Methods: In vitro, RAW264.7 cells were pretreated with H151 then stimulated with recombinant murine (rm) CIRP, and IFN-β levels in the culture supernatant were measured at 24 hours after stimulation. In vivo, male C57BL/6 mice were subjected to 60-minute intestinal ischemia via superior mesenteric artery occlusion. At the time of reperfusion, mice were intraperitoneally instilled with H151 (10 mg/kg BW) or 10% Tween-80 in PBS (vehicle). Four hours after reperfusion, the small intestines, lungs, and serum were collected for analysis. Mice were monitored for 24 hours after intestinal I/R to assess survival. Results: In vitro, H151 reduced rmCIRP-induced IFN-β levels in a dose-dependent manner. In vivo, intestinal levels of pIRF3 were increased after intestinal I/R and decreased after H151 treatment. There was an increase in serum levels of tissue injury markers (lactate dehydrogenase, aspartate aminotransferase) and cytokine levels (interleukin 1β, interleukin 6) after intestinal I/R, and these levels were decreased after H151 treatment. Ischemia-reperfusion-induced intestinal and lung injury and inflammation were significantly reduced after H151 treatment, as evaluated by histopathologic assessment, measurement of cell death, chemokine expression, neutrophil infiltration, and myeloperoxidase activity. Finally, H151 improved the survival rate from 41% to 81% after intestinal I/R. Conclusions: H151, a novel STING inhibitor, attenuates the inflammatory response and reduces tissue injury and mortality in a murine model of intestinal I/R. H151 shows promise as a potential therapeutic in the treatment of this disease.

Topics: Animals; Aspartate Aminotransferases; Chemokines; Cytokines; Inflammation; Interferon Type I; Interleukin-1beta; Interleukin-6; Intestines; Lactate Dehydrogenases; Male; Membrane Proteins; Mesenteric Ischemia; Mice; Mice, Inbred C57BL; Peroxidase; Reperfusion Injury; RNA-Binding Proteins

Oxidative damage is critical in the pathogenesis of ovarian ischaemia/reperfusion (I/R) injury, and statins have been reported to exert antioxidant activity. However, the role of VCAM-1 and xanthine oxidase (XO)/uric acid (UA) in ovarian I/R injury is not known. Also, whether or not atorvastatin exerts antioxidant activity like other statins is unclear.. This study investigated the involvement of VCAM-1 and XO/UA in ovarian I/R injury and the likely protective role of atorvastatin.. Forty female Wistar rats were randomized into sham-operated, ischaemia, ischaemia/reperfusion (I/R), ischaemia and atorvastatin, and I/R and atorvastatin.. In comparison with the sham-operated group, atorvastatin blunted ischaemia and I/R-induced distortion of ovarian histoarchitecture and follicular degeneration. Also, atorvastatin alleviated ischaemia and I/R-induced rise in XO, UA, and malondialdehyde, which was accompanied by inhibition of ischaemia and I/R-induced reductions in reduced glutathione level, enzymatic antioxidant activities and increase in myeloperoxidase activity and TNF-α and IL-6 levels by atorvastatin treatment. Additionally, atorvastatin blocked ischaemia and I/R-induced increase in VCAM-1 expression, caspase 3 activity, 8-hydroxydeoxyguanosine level and ovarian DNA fragmentation index.. For the first time, this study revealed that atorvastatin-mediated downregulation of VCAM-1 and XO/UA/caspase 3 signaling averts oxidative injury, inflammation, and apoptosis induced by ovarian ischaemia/reperfusion injury.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Antioxidants; Apoptosis; Atorvastatin; Caspase 3; Down-Regulation; Female; Glutathione; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Interleukin-6; Ischemia; Malondialdehyde; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Tumor Necrosis Factor-alpha; Uric Acid; Vascular Cell Adhesion Molecule-1; Xanthine Oxidase

Liraglutide, a glucagon-like peptide-1 receptor (GLP-1R) agonist, has been reported to exert protective effects against myocardial, hepatic, and gastric ischemia-reperfusion injury (IRI), but whether it can protect against renal IRI remains unknown. Here, a lethal renal IRI model was established with a 100% mortality rate in untreated mice. Treatment with liraglutide involving a regimen of multiple doses resulted in 100% survival, remarkable preservation of renal function, a significant reduction in pathological damage, and blunted upregulation of TNF-α, IL-1β, IL-6, MCP-1, TLR-2, TLR-4, and RAGE mRNA. We found that liraglutide treatment dramatically inhibited ischemia-induced nucleocytoplasmic translocation and release of HMGB1. This inhibition was associated with a marked decrease (~ 60%) in nuclear histone acetyltransferase activity. In addition, the protective effects of liraglutide on renal IRI were largely abolished by the administration of exogenous HMGB1. When the GLP-1R antagonist exendin (9-39) was given to mice before each liraglutide administration, or GLP-1R

Topics: Animals; Cell Line; Cytokines; Glucagon-Like Peptide-1 Receptor; HMGB1 Protein; Humans; Hypoglycemic Agents; Kidney; Liraglutide; Male; Mice, Inbred C57BL; Mice, Knockout; Peroxidase; Protective Agents; Protein Transport; Reperfusion Injury

Ischemia reperfusion (I/R)‑induced intestinal injury is a pathophysiological process leading to oxidative stress and inflammatory responses, and revealing its underlying mechanisms is essential for developing therapeutic strategies. Cyclooxygenase (COX) has been reported to be involved in I/R injury. Parecoxib sodium, a selective inhibitor for COX‑2, exerts protective effects, such as reducing I/R‑induced injuries in the heart, kidney and brain. However, the potential role of parecoxib sodium in protecting the small intestine against I/R‑induced injury has rarely been investigated. Therefore, the aim of the present study was to elucidate the effects and potential mechanisms of parecoxib sodium in I/R‑induced intestinal injury. In total, 60 Sprague‑Dawley rats were randomly divided into four groups: Control (sham operation) group, intestinal I/R group, 10 mg/kg parecoxib sodium‑pre‑treated I/R (I/R + Pare/10) group and the 20 mg/kg parecoxib sodium‑pre‑treated I/R (I/R + Pare/20) group. A regular I/R model was established to induce the intestinal injury in rats. Parecoxib sodium at 10 or 20 mg/kg was intraperitoneally administered into rats in both I/R + Pare groups once daily for 5 consecutive days prior to ischemia. Blood samples and small intestinal tissues were collected at 2 h after reperfusion. Changes in the levels of malondialdehyde, nitric oxide, interleukin (IL)‑1β, IL‑8, intercellular cell adhesion molecule‑1 and IL‑10, as well as the total antioxidant capacity were determined using ELISA, as were the activities of superoxidase dismutase and myeloperoxidase. Furthermore, the protein expression levels of total caspase‑3, cleaved caspase‑3, Bcl‑2 and Bax were examined via western blot analysis. In addition, the daily survival rate post‑reperfusion was examined for 7 days. It was revealed that parecoxib sodium increased the levels of antioxidants and suppressed the intestinal oxidative injury induced by I/R. Moreover, parecoxib sodium downregulated the expression levels of the proinflammatory factors, but upregulated the expression levels of anti‑inflammatory factors. The results also demonstrated that parecoxib sodium attenuated I/R‑induced apoptosis and increased the survival rate of rats. Thus, administration of parecoxib sodium prior to intestinal I/R attenuated intestinal injury and increased the rat survival rate by inhibiting I/R‑induced inflammation, oxidative stress and apoptosis.

Topics: Animals; Anti-Inflammatory Agents; Apoptosis; Cyclooxygenase 2 Inhibitors; Inflammation; Isoxazoles; Male; Malondialdehyde; Oxidative Stress; Peroxidase; Protective Agents; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Signal Transduction

Renal ischaemia reperfusion (I/R) triggers a cascade of events including oxidative stress, apoptotic body and microparticle (MP) formation as well as an acute inflammatory process that may contribute to organ failure. Macrophages are recruited to phagocytose cell debris and MPs. The tyrosine kinase receptor MerTK is a major player in the phagocytosis process. Experimental models of renal I/R events are of major importance for identifying I/R key players and for elaborating novel therapeutical approaches. A major aim of our study was to investigate possible involvement of MerTK in renal I/R. We performed our study on both natural mutant rats for MerTK (referred to as RCS) and on wild type rats referred to as WT. I/R was established by of bilateral clamping of the renal pedicles for 30' followed by three days of reperfusion. Plasma samples were analysed for creatinine, aspartate aminotransferase (ASAT), lactate dehydrogenase (LDH), kidney injury molecule -1 (KIM-1), and neutrophil gelatinase-associated lipocalin (NGAL) levels and for MPs. Kidney tissue damage and CD68-positive cell requirement were analysed by histochemistry. monocyte chemoattractant protein-1 (MCP-1), myeloperoxidase (MPO), inducible nitric oxide synthase (iNOS), and histone 3A (H3A) levels in kidney tissue lysates were analysed by western blotting. The phagocytic activity of blood-isolated monocytes collected from RCS or WT towards annexin-V positive bodies derived from cultured renal cell was assessed by fluorescence-activated single cell sorting (FACS) and confocal microscopy analyses. The renal I/R model for RCS rat described for the first time here paves the way for further investigations of MerTK-dependent events in renal tissue injury and repair mechanisms.

Topics: Acute Kidney Injury; Animals; Aspartate Aminotransferases; c-Mer Tyrosine Kinase; Cell Adhesion Molecules; Chemokine CCL2; Creatinine; Humans; Kidney; L-Lactate Dehydrogenase; Lipocalin-2; Macrophages; Nitric Oxide; Nitric Oxide Synthase Type II; Peroxidase; Phagocytosis; Rats; Reperfusion Injury

Tumor necrosis factor-alpha (TNF-α) has an important role in hypoxia/reoxygenation (H/R)-induced intestinal damage. It was shown that blocking TNF-α with infliximab has beneficial effects on experimental necrotizing enterocolitis and hypoxic intestinal injury. However, there is no data about the effect of adalimumab on H/R-induced intestinal damage. Therefore, we aimed to determine potential dose-dependent benefits of adalimumab in such damage in neonatal rats. Wistar albino rat pups were assigned to one of the four groups: control group, hypoxia group, low-dose adalimumab (5 mg/kg/day) treated group (LDAT), and high-dose adalimumab (50 mg/kg/day) treated group (HDAT). On the fourth day of the experiment, all rats except for the control group were exposed to H/R followed by euthanasia. Malondialdehyde (MDA), myeloperoxidase (MPO), TNF-α, total antioxidant capacity (TAC), and total oxidant capacity (TOC) were measured in intestinal tissue. TAC and TOC values were used to calculate the oxidative stress index (OSI). Histopathological injury scores (HIS) were also evaluated in the tissue samples. MDA levels were significantly lower in the LDAT and HDAT groups (p < 0.001). TNF-α levels were significantly lower in the LDAT group (p < 0.001). OSI was significantly higher in the H/R group than in the control and LDAT groups (p < 0.001). Mean HIS values in the LDAT group were significantly lower than those in the H/R and HDAT groups (p < 0.001). This experimental study showed that low-dose adalimumab appears to have a beneficial effect on intestinal injury induced with H/R in neonatal rats.

Topics: Adalimumab; Animals; Animals, Newborn; Antioxidants; Disease Models, Animal; Dose-Response Relationship, Drug; Enterocolitis, Necrotizing; Hypoxia; Malondialdehyde; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Global cerebral ischemia/reperfusion (I/R) induces selective neuronal injury in the hippocampus, leading to severe impairment in behavior, learning, and memory functions. This study aimed to evaluate the neuroprotective effects of bisoprolol (biso) and vitamin E (vit E) treatment alone or in combination on cerebral ischemia/reperfusion (I/R) injury. A total of 30 male rats were divided randomly into five groups (n = 6), sham, I/R, I/R + biso, I/R + vit E, and I/R + biso+vit E. Cerebral I/R group underwent global ischemia by bilateral common carotid artery occlusion for 20 min. Treatment groups received drugs once daily intraperitoneally for 7 days before the I/R induction. Locomotive and cognitive behaviors were utilized by open-field and Morris water maze tests. After behavioral testing, the brain was removed and processed to evaluate cerebral infarct size, histopathologic changes, myeloperoxidase (MPO) activity, and malondialdehyde (MDA) level. In I/R group tissue MDA and MPO levels and cerebral infarct size were significantly increased in comparison with the sham group. Furthermore, significant deficits were observed in locomotion and spatial memory after I/R. The areas of cerebral infarction, MPO, and MDA levels in biso, vit E, and combination group were significantly reduced compared with I/R group. Histopathological analysis demonstrated a significant reduction in leukocyte infiltration in all treated groups with the most profound reduction in the combination group. According to the behavioral tests, administration of biso and/or vit E protected locomotive ability and improved spatial memory after cerebral I/R. Our findings show that biso and vit E have beneficial effects against the I/R injury and due to their synergistic effects when administered in combination, may have a more pronounced protective effect on the cerebral I/R injury.

Topics: Animals; Antioxidants; Bisoprolol; Brain; Brain Ischemia; Drug Synergism; Drug Therapy, Combination; Male; Malondialdehyde; Neuroprotection; Neuroprotective Agents; Peroxidase; Rats, Wistar; Reperfusion Injury; Vitamin E

With high unmet medical needs, stroke remains an intensely focused research area. Although noscapine is a neuroprotective agent, its mechanism of action in ischemic-reperfusion (I-R) injury is yet to be ascertained. We investigated the effect of noscapine on the molecular mechanisms of cell damage using yeast, and its neuroprotection on cerebral I-R injury in rats. Yeast, both wild-type and Δtrx2 strains, was evaluated for cell growth and viability, and oxidative stress to assess the noscapine effect at 8, 10, 12, and 20 μg/ml concentrations. The neuroprotective activity of noscapine (5 and 10 mg/kg; po for 8 days) was investigated in rats using middle cerebral artery occlusion-induced I-R injury. Infarct volume, neurological deficit, oxidative stress, myeloperoxidase activity, and histological alterations were determined in I-R rats. In vitro yeast assays exhibited significant antioxidant activity and enhanced cell tolerance against oxidative stress after noscapine treatment. Similarly, noscapine pretreatment significantly reduced infarct volume and edema in the brain. The neurological deficit was decreased and oxidative stress biomarkers, superoxide dismutase activity and glutathione levels, were significantly increased while lipid peroxidation showed significant decrease in comparison to vehicle-treated I-R rats. Myeloperoxidase activity, an indicator of inflammation, was also reduced significantly in treated rats; histological changes were attenuated with noscapine. The study demonstrates the protective effect of noscapine in yeast and I-R rats by improving cell viability and attenuating neuronal damage, respectively. This protective activity of noscapine could be attributed to potent free radical scavenging and inhibition of inflammation in cerebral ischemia-reperfusion injury.

Topics: Animals; Brain; Gait; Infarction, Middle Cerebral Artery; Male; Muscle Strength; Neuroprotective Agents; Noscapine; Oxidative Stress; Peroxidase; Psychomotor Performance; Rats, Wistar; Reperfusion Injury; Saccharomyces cerevisiae

Hepatic ischemia/reperfusion (I/R) injury is a syndrome involved in allograft dysfunction. This work aimed to elucidate carvedilol (CAR) role in hepatic I/R injury.. Male rats were allocated to Sham group, CAR group, I/R group and CAR plus I/R group. Rats subjected to hepatic ischemia for 30 minutes then reperfused for 60 minutes. Oxidative stress markers, inflammatory cytokines and nitric oxide synthases were measured in hepatic tissues.. Hepatocyte injury following I/R was confirmed by a marked increase in liver enzymes. Also, hepatic I/R increased the contents of malondialdehyde however decreased glutathione contents and activities of antioxidant enzymes. Furthermore, hepatic I/R caused elevation of toll-like receptor-4 (TLR-4) expression and inflammatory mediators levels such as tumor necrosis factor-α, interleukin-6 and cyclooxygenase-II. Hepatic I/R caused down-regulation of endothelial nitric oxide synthase and upregulation of inducible nitric oxide synthase expressions. CAR treatment before hepatic I/R resulted in the restoration of liver enzymes. Administration of CAR caused a significant correction of oxidative stress and inflammation markers as well as modulates the expression of endothelial and inducible nitric oxide synthase.. CAR protects liver from I/R injury through reduction of the oxidative stress and inflammation, and modulates endothelial and inducible nitric oxide synthase expressions.

Topics: Adrenergic Antagonists; Animals; Anti-Inflammatory Agents; Carvedilol; Cyclooxygenase 2; Interleukin-6; Liver; Liver Diseases; Male; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Oxidative Stress; Peroxidase; Rats, Wistar; Reperfusion Injury; Signal Transduction; Toll-Like Receptor 4; Tumor Necrosis Factor-alpha

Use of normothermic ex vivo lung perfusion (EVLP) was adopted in clinical practice to assess the quality of marginal donor lungs. Subnormothermic perfusion temperatures are in use among other solid organs to improve biochemical, clinical and immunological parameters. In a rat EVLP model of donation after circulatory death (DCD) lung donors, we tested the effect of four subnormothermic EVLP temperatures that could further improve organ preservation. Warm ischemic time was of 2 hours. EVLP time was of 4 hours. Lung physiological data were recorded and metabolic parameters were assessed. Lung oxygenation at 21°C and 24°C were significantly improved whereas pulmonary vascular resistance and edema formation at 21°C EVLP were significantly worsened when compared to 37°C EVLP. The perfusate concentrations of potassium ions and lactate exiting the lungs with 28°C EVLP were significantly lower whereas sodium and chlorine ions with 32°C EVLP were significantly higher when compared to 37°C EVLP. Also compared to 37°C EVLP, the pro-inflammatory chemokines MIP2, MIP-1α, GRO-α, the cytokine IL-6 were significantly lower with 21°C, 24°C and 28°C EVLP, the IL-18 was significantly lower but only with 21°C EVLP and IL-1β was significantly lower at 21°C and 24°C EVLP. Compared to the 37°C EVLP, the lung tissue ATP content after 21°C, 24°C and 28°C EVLP were significantly higher, the carbonylated protein content after 28°C EVLP was significantly lower and we measured significantly higher myeloperoxidase activities in lung tissues with 21°C, 24°C and 32°C. The 28°C EVLP demonstrated acceptable physiological variables, significantly higher lung tissue ATP content and decreased tissue carbonylated proteins with reduced release of pro-inflammatory cytokines. In conclusion, the 28°C EVLP is a non inferior setting in comparison to the clinically approved 37°C EVLP and significantly improve biochemical, clinical and immunological parameters and may reduce I/R injuries of DCD lung donors.

Topics: Adenosine Triphosphate; Animals; Chemokines; Lung; Male; Oxygen; Perfusion; Peroxidase; Protein Carbonylation; Rats, Sprague-Dawley; Reperfusion Injury; Temperature; Tissue Donors; Wound Healing

Edaravone is a potent free radical scavenger that has a promising role in combating many acute lung injuries. Ischemia/reperfusion process is a serious condition that may lead to multiple organ dysfunctions. This work was designed to investigate novel mechanisms underlying ischemia/reperfusion-induced lung injury and to evaluate the protective role of edaravone. Thirty adult male rats were divided into three experimental groups; operated with no ischemia (Sham-group), ischemia/reperfusion (I/R) group and edaravone-I/R group. Hind limb ischemia was carried out by clamping the femoral artery. After two hours of ischemia for the hind limb, the rat underwent 24h of reperfusion. Rats in the edaravone-I/R group received edaravone (3mg/kg), 30min before induction of ischemia. At the end of the I/R trial, specimens from the lungs were processed for histological, immunohistochemical, enzyme assay, and RT-qPCR studies. Specimens from I/R group showed focal disruption of the alveolar architecture. Extensive mononuclear cellular infiltration particularly with neutrophils and dilated congested blood capillaries were observed. A significant increase in iNOS, NF-κB, and COX-2 immunoreaction was detected and confirmed by RT-qPCR. Ultrastructural examination showed RBCs and fluid inside alveoli, cellular infiltration, and vacuolations of the inter-alveolar septum. In addition to the presence of extravasated neutrophils and RBCs within the inter-alveolar septum. In contrast, minimal changes were observed in rats which received edaravone before the onset of the ischemia. It could be concluded that edaravone exerted a potent protective effect against lung injury induced by a hind limb I/R in rats through its antioxidant and anti-inflammatory activities.

Topics: Animals; Biochemical Phenomena; Disease Models, Animal; Edaravone; Electron Transport Complex IV; Hindlimb; Immunohistochemistry; Lung; Lung Injury; Male; Microscopy, Electron, Transmission; Neuroprotective Agents; NF-kappa B; Nitric Oxide Synthase Type II; Oxidative Stress; Peroxidase; Random Allocation; Rats; Rats, Wistar; Real-Time Polymerase Chain Reaction; Reperfusion Injury

Topics: Animals; Cytoprotection; Dinoprostone; Dose-Response Relationship, Drug; Intercellular Signaling Peptides and Proteins; Male; Nitric Oxide; Peroxidase; Rats; Rats, Wistar; Receptor, Cholecystokinin B; Reperfusion Injury; Sensory Receptor Cells; Stomach; Vagus Nerve

Kidney ischemia reperfusion (IR) injury is an important health problem resulting in acute kidney failure. The oxidative stress and inflammatory process are the underlying mechanisms of IR injury. It has been purposed in this study to research the possible protective effects of fraxin on kidney injury induced by IR.. 32 Sprague Dawley male rats were divided into 4 groups. The groups were organized as follows; sham, IR, IR + fraxin 10 mg/kg, and IR + 50 mg/kg fraxin groups. Some oxidant, antioxidant and inflammatory parameters were evaluated in kidney tissues removed at the end of our experimental study.. It was detected that the oxidant and proinflammatory markers increased and antioxidant parameters decreased in IR group but the results significantly reversed in treatment groups compared to IR group. And also, 8-OHdG, NF-κB, HAVCR1 immunopositivities were at severe levels and these results attenuated in IR fraxin + 10 mg/kg, and IR + fraxin 50 mg/kg groups.. These presented results have shown that fraxin performed protective effects against kidney injury induced by IR.

Topics: Acute Kidney Injury; Animals; Antioxidants; Coumarins; Disease Models, Animal; Kidney; Male; Malondialdehyde; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase

Liver ischemia reperfusion (I/R) damage which is frequently seen in clinical hepatobiliary surgeries has no effective treatment for it. Liv-52, known to have hepatoprotective effects, is a natural antioxidant drug licensed by the Ministry of Health of India. The aim of our study is to investigate the effect of Liv-52 on liver damage induced by I/R in rats.. Albino Wistar male rats were divided into three groups; liver I/R (IR), 20 mg/kg Liv-52 + liver ischemia reperfusion (LIR) and sham operation applied to control group (HG). Liv-52 was administered to the LIR group (n = 6) 1 h prior to I/R application and distilled water was given orally to IR (n = 6) and HG (n = 6) groups as a solvent. Ischemia was determined as 1 h, and reperfusion was identified as 6 h in animals.. Increased levels of alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase, malondialdehyde, myeloperoxidase, and decreased levels of superoxide dismutase, and glutathione related enzymes caused by I/R application have been converged to healthy group level with Liv-52 treatment and the damage in liver tissue has been improved histopathologically.. Liv-52 may be beneficial for preventing liver I/R damage in pre-surgery application.

Topics: Alanine Transaminase; Animals; Antioxidants; Aspartate Aminotransferases; Drug Combinations; Glutathione; Glutathione Peroxidase; Glutathione Reductase; Glutathione Transferase; L-Lactate Dehydrogenase; Liver; Male; Malondialdehyde; Peroxidase; Plant Extracts; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase

Acute kidney injury (AKI) complicated by acute lung injury has a detrimental effect on mortality among critically ill patients. Recently, a renal ischemia-reperfusion (IR) model suggested the involvement of histones and neutrophil extracellular traps (NETs) in the development of distant lung injury after renal IR. Given that recombinant thrombomodulin (rTM) has anti-inflammatory roles by binding to circulating histones, we aimed to clarify its effect on distant lung injury induced by AKI in a murine bilateral renal IR model. Both pretreatment and delayed treatment with rTM significantly decreased pulmonary myeloperoxidase activity, but they did not affect renal dysfunction at 24 h after renal IR. Additionally, rTM mitigated the renal IR-augmented expression of proinflammatory cytokines (tumor necrosis factor-α, interleukin-6, and keratinocyte-derived chemokine), and vascular leakage, as well as the degree of lung damage. Intense histone accumulation and active NET formation occurred in both the kidneys and the lungs; however, rTM significantly decreased the histone and NET accumulation only in the lungs. Administration of rTM may have protective impact on the lungs after renal IR by blocking histone and NET accumulation in the lungs, although no protection was observed in the kidneys. Treatment with rTM may be an adjuvant strategy to attenuate distant lung injury complicating AKI.

Topics: Acute Lung Injury; Animals; Blood Urea Nitrogen; Disease Models, Animal; Histones; HMGB1 Protein; Interleukin-6; Kidney; Lung; Male; Mice; Mice, Inbred C57BL; Peroxidase; Recombinant Proteins; Reperfusion Injury; Thrombomodulin; Tumor Necrosis Factor-alpha

Renal ischemia-reperfusion injury (IRI) is a major cause of acute kidney injury (AKI) and even induces remote organ damage. Accumulating proofs demonstrates that the endocannabinoid system may provide a promising access for treatment strategy of renal IRI associated AKI. In the current study, using the established renal IRI model of rat, we tested the hypothesis that pretreatment of URB602, 30 min before renal IRI, alleviates kidney injury and relevant distant organ damage via limiting oxidative stress and inflammation. Using Western blot analysis and LC-MS/MS, renal IRI showed to increase the levels of 2-arachidonoylglycerol (2-AG) in kidneys as well as COX-2, PGE2, TXA2, and decrease N-arachidonoylethanolamine (anandamide, AEA); the expressions of renal cannabinoid receptor 1 (CB1) and cannabinoid receptor 2 (CB2) were unchanged. The URB602 pretreatment in renal IRI, further enhanced renal 2-AG which is high affinity to both CB1 and CB2, and reduced renal COX-2 which is involved in the regulation of renal perfusion and inflammation. AM630 (CB2 antagonist) almost blocked all the antioxidant, anti-inflammatory and nephroprotective effects of URB602, whereas AM251 (CB1 antagonist) showed limited influence, and parecoxib (COX-2 inhibitor) slightly ameliorated renal function at the dose of 10 mg/kg. Taken together, our data indicate that URB602 acts as a reactive oxygen species scavenger and anti-inflammatory media in renal IRI mainly depending on the activation of CB2.

Topics: Aldosterone; Animals; Biphenyl Compounds; Chromatography, Liquid; Interleukin-1beta; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Receptor, Cannabinoid, CB2; Reperfusion Injury; Superoxide Dismutase; Tandem Mass Spectrometry; Tumor Necrosis Factor-alpha

The aim of the present study was to investigate the antioxidant mechanisms of dexmedetomidine against lung injury during intestinal ischemia reperfusion (IIR) in rats. The model of IIR‑induced acute lung injury was established by occluding the superior mesenteric artery (SMA) for 1 h and reperfusing for 2 h using Sprague‑Dawley rats. Pathological examination was used to assess the extent of the lung injury. Oxidative stress was evaluated by measuring malondialdehyde, myeloperoxidase and superoxide dismutase in the lung and plasma. The proinflammatory cytokines tumor necrosis factor‑α and interleukin‑6 were determined via an enzyme‑linked immunosorbent assay. The mRNA and protein expression of nuclear factor‑erythroid 2 related factor 2 (Nrf2) and heme oxygenase 1 (HO‑1) were determined using a reverse transcription‑quantitative polymerase chain reaction and western blotting. Pretreatment with dexmedetomidine significantly inhibited the oxidative stress response and proinflammatory factor release caused by IIR compared with the normal saline group (MDA and SOD in lung and plasma, P<0.05; MPO, IL‑1β and TNF‑α in lung and plasma, P<0.05). Dexmedetomidine improved pulmonary pathological changes in IIR rats compared with the normal saline group. Investigations into the molecular mechanism revealed that dexmedetomidine increased the expression levels of Nrf2 and HO‑1 via activating α2 adrenergic receptors compared with the normal saline group. The antagonism of α2 adrenergic receptors may reverse the protective effect of dexmedetomidine on lung injury during IIR, including decreasing the expression levels of Nrf2 and HO‑1, elevating the oxidative stress response and increasing the proinflammatory factor release. In conclusion, pretreatment with dexmedetomidine demonstrated protective effects against lung injury during IIR via α2 adrenergic receptors. The Nrf2/HO‑1 signaling pathway may serve a function in the protective effect of dexmedetomidine.

Topics: Acute Lung Injury; Animals; Antioxidants; Cytokines; Dexmedetomidine; Disease Models, Animal; Heme Oxygenase-1; Lung; Male; Malondialdehyde; NF-E2 Transcription Factor; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Signal Transduction; Superoxide Dismutase

D-allose was promising in the protection of ischemia/reperfusion (I/R) injury. We intended to investigate the function of D-allose in skin flap of rat followed by the injury of I/R and whether ERK signal pathway was involved in.. The back flap of Wistar rats was picked up with a vascular bundle of the lateral chest wall. I/R model was made by the venous clamp for 6 h. Rats received D-allose and PD-98059, the inhibitor of ERK1/2, 30 min before modeling. Morphology of tissue was observed by HE staining. Nitric oxide (NO), myeloperoxidase (MPO), malondialdehyde (MDA) and superoxide dismutase (SOD) levels in skin flap were determined by ELISA kits. mRNA and protein levels were determined by qPCR and Western blot respectively.. D-allose alleviated the condition of pathological changes and raised the survival rate of skin flap injured by I/R. Moreover, D-allose suppressed NO, MPO and MDA while elevated SOD levels during I/R status. Furthermore, D-allose decreased MCP-1, TNF-α, IL-1β and IL-6 levels in skin flap injured by I/R. In addition, D-allose inhibited MKP-1 expression and activated ERK1/2 pathway in skin flap injured by I/R. PD-98059 partially counteracted D-allose effects on I/R injury.. D-allose exerted its protective function via inhibiting MKP-1expression and further activated ERK1/2 pathway to suppress the progress of oxidative stress, inflammation and necrosis, contributing to the survival of skin flap injured by I/R. Thus, D-allose was promising in the transplantation of skin flap.

Topics: Animals; Dual Specificity Phosphatase 1; Flavonoids; Glucose; Male; Malondialdehyde; MAP Kinase Signaling System; Nitric Oxide; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase; Surgical Flaps; Treatment Outcome

To investigate the effects of bradykinin on reperfusion injury in an experimental intestinal ischemia reperfusion model.. We used 32 Wistar-Albino rats. We composed 4 groups each containing 8 rats. Rats in sham group were sacrified at 100 minutes observation after laparotomy. Thirty minutes reperfusion was performed following 50 minutes ischaemia in control group after observing 20 minutes. Ischaemic preconditioning was performed in one group of the study. We performed the other study group pharmacologic preconditioning by infusional administration of 10 μg/kg/minute bradykinin intravenously. We sacrified all of the rats by taking blood samples to evaluate the lactate and lactate dehydrogenase (LDH) after resection of jejunum for detecting tissue myeloperoxidase (MPO) activity.. Lactate and LDH levels were significantly higher in control and study groups than the sham group (P<0.001). There is no difference between the study groups statistically. (P>0.05). The results were the same for MPO levels. Although definitive cell damage was determinated in the control group by hystopatological evaluation, the damage in the study groups observed was lower in different levels. However, there was no significant difference between the study groups statistically (P>0.05).. Either ischeamic preconditioning or pharmacologic preconditioning made by bradykinin reduced the ischemia reperfusion injury at jejunum.

Topics: Animals; Bradykinin; Disease Models, Animal; Female; Intestine, Small; Ischemic Preconditioning; Laparotomy; Peroxidase; Random Allocation; Rats, Wistar; Reference Values; Reperfusion Injury; Reproducibility of Results; Time Factors; Treatment Outcome; Vasodilator Agents

The aim of the study was to evaluate the protective effect of Botulinum A toxin injection against ischemia-reperfusion injury.. Thirty-two Sprague-Dawley rats were divided into: control, ischemia-reperfusion, ischemic preconditioning, and botulinum groups. In all groups the musculocutaneous pedicle flap was occluded for 4 h, and then reperfused to induce ischemia-reperfusion injury. Serum and tissue myeloperoxidase (MPO) and nitric oxide (NO) levels were measured at 24 h and at 10 days.. Tissue MPO levels did not differ significantly between the ischemic preconditioning and botulinum groups at 24 h but was significantly lower in the botulinum group at 10 days. Tissue NO levels were significantly higher in the ischemic preconditioning group compared to the botulinum group at 24 h and at 10 days. Serum MPO showed no significant difference between these two groups at 24 h but was significantly lower in the ischemic preconditioning group compared to the botulinum group at 10 days. Serum NO levels were not significantly different at 24 h but significantly higher in the botulinum group at 10 days.. Findings show that botulinum has a protective effect against the ischemia-reperfusion injury via increased NO and decreased MPO levels in tissue. Based on tissue NO levels, ischemic preconditioning was significantly higher than botulinum.

Topics: Animals; Botulinum Toxins, Type A; Female; Ischemic Preconditioning; Muscle, Skeletal; Myocutaneous Flap; Nitric Oxide; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

The reno-protective effects of antidiabetic dipeptidyl peptidase (DPP)-4 inhibitors have been studied regarding their antioxidant and anti-inflammatory properties. However, the potential ability of saxagliptin to ameliorate renal injury by enhancing neovascularization has not been elucidated. To address this issue, saxagliptin (10 and 30 mg/kg) was administered to Wistar rats after the induction of renal ischaemia/reperfusion (I/R). Our results showed that saxagliptin operated through different axes to ameliorate I/R injury. By inhibiting DPP-4, saxagliptin maintained stromal cell-derived factor-1α expression and upregulated its chemokine receptor CXCR4 to trigger vasculogenesis through the enhanced migration of endothelial progenitor cells (EPCs). Additionally, this compound rescued the levels of glucagon-like peptide-1 and its downstream mediator cAMP to increase vascular endothelial growth factor (VEGF) and CXCR4 levels. Moreover, saxagliptin stimulated atrial natriuretic peptide/endothelial nitric oxide synthase to increase nitric oxide levels and provoke angiogenesis and renal vasodilation. In addition to inhibiting DPP-4, saxagliptin increased the renal kidney injury molecule-1/pY705-STAT3/hypoxia-inducible factor-1α/VEGF pathway to enhance angiogenesis. Similar to other gliptins, saxagliptin exerted its anti-inflammatory and antioxidant effects by suppressing the renal contents of p (S536)-nuclear factor-κB p65, tumour necrosis factor-α, monocyte chemoattractant protein-1, myeloperoxidase, and malondialdehyde while boosting the glutathione content. These events improved the histological structure and function of the kidney, as evidenced by decreased serum creatinine, blood urea nitrogen, and cystatin C and increased serum albumin. Accordingly, in addition to its anti-inflammatory and antioxidant activities, saxagliptin dose-dependently ameliorated I/R-induced renal damage by enhancing neovascularization through improved tissue perfusion and homing of bone marrow-derived EPCs to mediate repair processes.

Topics: Adamantane; Animals; Atrial Natriuretic Factor; Cell Adhesion Molecules; Chemokine CXCL12; Cyclic AMP; Dipeptides; Disease Models, Animal; Glucagon-Like Peptide 1; Glutathione; Hypoxia-Inducible Factor 1, alpha Subunit; Kidney; Male; Malondialdehyde; Neovascularization, Physiologic; Nitric Oxide; Nitric Oxide Synthase Type III; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Receptors, CXCR4; Reperfusion Injury; Signal Transduction; STAT3 Transcription Factor; Vascular Endothelial Growth Factor A

The aim of the present study was to investigate the effect of resveratrol on cytokine levels and oxidative stress in intestinal ischemia/reperfusion (I/R) injuries.. To induce intestinal I/R, the superior mesenteric artery was occluded for 30 min and then reperfused for 150 min or 24 h. The therapeutic effects of resveratrol on the damage from intestinal I/R were investigated using an isolated organ bath, along with oxidant/antioxidant and inflammatory factors such as glutathione (GSH), malondialdehyde (MDA), myeloperoxidase (MPO), interleukin-(IL)-1β, and tumor necrosis factor alpha (TNF-α).. I/R control animals demonstrated severe deterioration of smooth muscle motor function as a significant decrease in potassium chloride- and acetylcholine-induced a contractile responses; high oxidative stress as an increase in lipid peroxidation and a decrease in GSH level; and an increase of MPO, IL-1β, and TNF-α activity. Pretreatment of animals with resveratrol restored intestinal dysfunction; reduced elevated MDA, MPO, IL-1β, and TNF-α levels; and reversed the depleted intestine GSH levels after both 150 min and 24 h reperfusion periods.. The results indicated that resveratrol can reverse the effects of disrupted smooth muscle contractility, probably because of its antioxidant and anti-inflammatory effects on MPO, IL-1β, and TNF-α activities.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Disease Models, Animal; Glutathione; Interleukin-1beta; Intestine, Small; Male; Malondialdehyde; Muscle Contraction; Muscle, Smooth; Oxidative Stress; Peroxidase; Rats, Wistar; Reperfusion Injury; Resveratrol; Signal Transduction; Tumor Necrosis Factor-alpha

To investigate the effect of sevoflurane preconditioning on ischemia/reperfusion (I/R)-induced pulmonary/hepatic injury.. Fifty-one Wistar rats were randomly grouped into sham, I/R, and sevoflurane groups. After reperfusion, the structural change of the lung was measured by Smith score, the wet and dry weights (W/D) were determined, malondialdehyde (MDA) myeloperoxidase (MPO) content was determined colorimetrically and by fluorescence, respectively, and matrix metalloprotein-9 (MMP-9) mRNA was quantified by RT-PCR. Biopsy and morphological analyses were performed on liver tissue, activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were determined, and tumor necrosis factor-alpha (TNF-α) level was determined.. The sham group showed no changes in tissue structure. Structural lesions in the sevoflurane and I/R groups were mild and severe, respectively. Smith score, W/D, MDA, MPO, and MMP mRNA showed the same trend, and were increased in the I/R group and recovered in the sevoflurane group, compared with the sham group (both P<0.05). AST and ALT were significantly increased compared to the sham group (AST: 655±52.06 vs . 29±9.30 U/L; ALT: 693±75.56 vs . 37±6.71 U/L; P<0.05). In the sevoflurane group, AST and ALT levels were significantly decreased (464±47.71 and 516±78.84 U/L; P<0.001). TNF-α presented similar results.. The protection of lung and liver by sevoflurane may be mediated by inhibited leukocyte recruitment and MMP-9 secretion.

Topics: Alanine Transaminase; Anesthetics, Inhalation; Animals; Aspartate Aminotransferases; Disease Models, Animal; Ischemia; Ischemic Preconditioning; Liver; Lung; Male; Malondialdehyde; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Sevoflurane; Tumor Necrosis Factor-alpha

Cisplatin (CP) is one of the most effective chemotherapeutics in the treatment of human cancers. However, the beneficial effects of CP are limited by the toxic effects, especially nephrotoxicity. Fluorofenidone (AKFPD) is a promising multifunctional antifibrosis pyridinone drug discovered by our group. But there is no evidence of its protective effects against acute kidney injury (AKI). Therefore, we investigated the protective effects of AKFPD on CP-induced AKI

Topics: Acute Kidney Injury; Animals; Antineoplastic Agents; Cell Line; Cisplatin; Copper Transporter 1; Gene Expression Regulation; Inflammation; Kidney; Male; Mice; Mice, Inbred C57BL; Mitogen-Activated Protein Kinase Kinases; Organic Cation Transporter 2; Peroxidase; Pyridones; Random Allocation; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Reperfusion Injury

To investigate the effect of Picroside II on testicular ischemia and reperfusion (l/R) injury and the underlying mechanism.. Sprague-Dawley rats were randomly divided into 4 groups: sham operated group (Sham), Sham with Picroside II treatment group (Sham+ Pic II), l/R group (l/R) and l/R with Picroside II treatment group (I/R+ Pic II). l/R model was established by rotating the left testis 720° in a clock-wise direction for 4 hours. The histopathologic and spermatogenetic evaluation was performed. The apoptosis changes and the levels of HO-1 (heme oxygenase-1), MPO (myeloperoxidase), NOX (NADPH oxidase), SOD (superoxide dismutase), XO (xanthine oxidase) and NOS (nitric oxide synthase) were measured.. The seminiferous tubules were damaged in l/R rats, but Picroside II alleviated the changes induced by l/R. The increased level of apoptosis was decreased by Picroside II (P=0.01, 9.05±0.35 vs. 4.85±0.25). The activities of HO-1, MPO, NOX, XO and MDA content were increased and the SOD activity was decreased in l/R (P<0.05) and could be reversed by Picroside II (P=0.03, 405.5±7.5 vs. 304±17U/mgprot; P=0.02, 0.99±0.05 vs. 0.52±0.04 mgprot; P=0.01, 260+7 vs. 189±2 mgprot; P=0.04, 10.95+0.55 vs. 8.75+0.35 U/mgprot; P=0.045, 6.8+0.7 vs. 3.75+0.35 mgprot; P=0.04, 44.5+3.5 vs. 57.5+3.5 mgprot). Western blot showed that the expression of iNOS, nNOS and eNOS were increased in l/R (P<0.05); however, they were decreased after Picroside II treatment (P<0.05).. Picroside II attenuated testicular I/R injury in rats mainly through suppressing apoptosis and oxidative stress through reduction of nitric oxide synthesis.

Topics: Animals; Apoptosis; Blotting, Western; Cinnamates; Heme Oxygenase-1; In Situ Nick-End Labeling; Iridoid Glucosides; Male; Malondialdehyde; NADP; Nitric Oxide; Oxidative Stress; Peroxidase; Random Allocation; Rats, Sprague-Dawley; Reperfusion Injury; Reproducibility of Results; Superoxide Dismutase; Testis; Xanthine Oxidase

Increased endothelial cell adhesion molecule (ECAM) expression, leukocyte-endothelial cell adhesive interactions (LECA), platelet-endothelial cell adhesion (PECA), mast cell activation, production of reactive oxygen species (ROS), and microvascular permeability are hallmarks of the inflammatory response. The infiltration of inflammatory phagocytes is associated with myeloperoxidase (MPO)-dependent production of hypochlorous acid, a reactive chlorinating species that targets membrane lipids to produce halogenated lipids such as 2-chlorohexadecanal (2-ClHDA) and 2-chloropalmitic acid (2-ClPA). Whether these chlorinated lipids contribute to microcirculatory dysfunction is largely unknown. Thus, the objectives of this study were to determine if chlorinated lipids exposure induces such inflammatory responses in an in vitro model employing cultured human intestinal mesenteric vascular endothelial cells (HIMVEC), and in an in vivo model examining responses in small intestinal and mesenteric postcapillary venules of naive rats. Following the addition of either 2-ClPA or 2-ClHDA to the culture medium, HIMVEC displayed increased platelet and neutrophil adherence that was associated with elevated expression of ECAMs and increased permeability. In vivo, chlorinated lipid exposure significantly increased LECA, PECA, ROS production, and albumin leakage, inflammatory events that were associated with mast cell activation and increased tissue MPO activity and expression. Our data provide proof-of-principle that 2-ClPA and 2-ClHDA induce powerful proinflammatory responses both in vitro and in vivo, suggesting the possibility that these chlorinated lipid products of the MPO/ hydrogen peroxide /chloride system may contribute to inflammation noted in neutrophil-dependent, myeloperoxidase-mediated pathologic states such as ischemia/reperfusion, hemorrhagic shock, and sepsis.

Topics: Aldehydes; Animals; Blood Platelets; Cell Adhesion; Cell Line; Endothelial Cells; Humans; Hypochlorous Acid; Inflammation; Male; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sepsis; Shock, Hemorrhagic

Limb ischemia/reperfusion (LI/R) injury is associated with high morbidity and mortality. The hypothesis of this study is that hydrogen-rich solution could attenuateacute lung injury and improve mortality via chemerin and NLRP3 after LI/R in rats. A rat model of LI/R was performed by clamping the bilateral femoral arteries for 3 h followed by reperfusion. Hydrogen-rich saline (HRS) was administered intraperitoneally (10 mL/kg or 2.5 mL/kg) when the atraumatic micro clips were released. The rats were euthanized at 2 h after reperfusion and then the arterial blood and lung specimens were harvested for further analyses. Meanwhile, survival rate was observed. The results showed that HRS improved the survival rate and attenuated pulmonary edema, injury, and apoptosis. HRS also decreased the levels of tumor necrosis factor-α, interleukin-6, myeloperoxidase and malondialdehyde, and increased the activity of superoxide dismutase in serum and lung after the LI/R event. HRS downregulated the expression of chemerin and NLRP3 in lung. The study demonstrated that chemerin and NLRP3 could serve as important response factors that were involved in the lung injury following LI/R. HRS could significantly attenuate LI/R-mediated acute lung injury, at least in part, by inhibiting the activated chemerin/NLRP3 signaling pathway.

Topics: Acute Lung Injury; Animals; Blood Gas Analysis; Chemokines; Enzyme-Linked Immunosorbent Assay; Hydrogen; Interleukin-6; Male; Malondialdehyde; NLR Family, Pyrin Domain-Containing 3 Protein; Oxidative Stress; Peroxidase; Pulmonary Edema; Rats; Rats, Wistar; Reperfusion Injury; Saline Solution; Tumor Necrosis Factor-alpha

Lipoxin A4 (LA4), a bioactive product of arachidonic acid, has been shown to exert strong anti-inflammatory activity. By contrast, the anti-inflammatory action of LA4 in a renal ischaemia-reperfusion (RIR)-mediated acute lung inflammation (ALI) model and the potential pathogenesis of the condition is still unclear. The aim of the current research was to investigate the effect of LA4 on RIR-induced ALI. The rat ALI model was induced by RIR. LA4 was injected via the tail vein immediately after RIR. The results indicate that LA4 markedly inhibits inflammatory cells infiltration, attenuates myeloperoxidase activity, and reduces the concentration of inflammatory mediators and Toll-like receptor 4 (TLR4) in RIR-induced ALI. Furthermore, LA4 suppressed nuclear factor kappa B (NF-κB) p65 and mitogen-activated protein kinase (MAPK) activation. The protective effect of LA4 in RIR-stimulated ALI was reversed by BOC-2 (an antagonist of the LA4 receptor). These results indicate that LA4 exerts powerful anti-inflammatory functions in RIR-induced ALI by attenuating TLR4 expression via MAPK and NF-κB signalling. Accordingly, LA4 might be an underlying treatment drug for RIR-induced ALI.

Topics: Acute Lung Injury; Animals; Bronchoalveolar Lavage Fluid; Cytoprotection; Gene Expression Regulation; HMGB1 Protein; Inflammation Mediators; Kidney; Lipoxins; Male; Mitogen-Activated Protein Kinases; NF-kappa B; Peroxidase; Phosphorylation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Toll-Like Receptor 4

Hydrogen-rich saline (HRS) has antioxidative, anti-inflammatory and anti-apoptotic properties. We investigated the effects of hydrogen on hepatic ischemia-reperfusion (I/R) and laparoscopic hepatectomy in swine.. Twenty-one healthy Bama miniature pigs were randomly divided into the sham group, ischemia-reperfusion injury (IRI) group, HRS-5 (5 mL/kg) group, and HRS-10 (10 mL/kg) group. HRS was injected through the portal vein 10 min before reperfusion and at postoperative day 1, 2 and 3. The roles of HRS on oxidative stress, inflammatory response and liver regeneration were studied.. Compared with the IRI group, HRS treatment attenuated oxidative stress by increasing catalase activity and reducing myeloperoxidase. White blood cells in the HRS-10 group were reduced compared with the IRI group (P < 0.01). In the HRS-10 group, interleukin-1 beta, interleukin-6 and tumor necrosis factor alpha, C-reactive protein and cortisol were downregulated, whereas interleukin-10 was upregulated. In addition, HRS attenuated endothelial cell injury and promoted the secretion of angiogenic cytokines, including vascular endothelial growth factor, angiopoietin-1 and angiopoietin-2. HRS elevated the levels of hepatocyte growth factor, Cyclin D1, proliferating cell nuclear antigen, Ki-67 and reduced the secretion of transforming growth factor-beta.. HRS treatment may exert a protective effect against I/R and hepatectomy-induced hepatic damage by reducing oxidative stress, suppressing the inflammatory response and promoting liver regeneration.

Topics: Angiogenic Proteins; Animals; Anti-Inflammatory Agents; Antioxidants; Catalase; Cell Cycle Proteins; Disease Models, Animal; Hepatectomy; Inflammation Mediators; Laparoscopy; Liver; Liver Diseases; Liver Regeneration; Oxidative Stress; Peroxidase; Reperfusion Injury; Saline Solution; Swine; Swine, Miniature; Time Factors

Gasdermin D (GSDMD), a genetic substrate for inflammatory caspases, plays a central role in pyroptosis of macrophages and release of interleukin‑1β (IL-1β), but was mainly referred to microbial infection. High mobility group box-1 (HMGB1), served as an alarm molecule during various pathological process, has been widely recognized to be involved in liver ischemia-reperfusion (I/R). Glycyrrhizin, a natural anti-inflammatory and antiviral triterpene in clinical use, was recently referred to have ability to prevent I/R induced liver injury by inhibiting HMGB1 expression and activity. However, the mechanisms responsible for damage amelioration subsequently to HMGB1 inhibition during liver I/R remain enigmatic. This study was designed to explore the functional role and molecular mechanism of glycyrrhizin in the regulation of I/R induced liver injury. We found that liver I/R promotes GSDMD-mediated pyroptotic cell death of Kupffer cells, which was inhibited by glycyrrhizin. Interestingly, endogenous HMGB1, not exogenous one, was involved in hypoxia-reoxygenation (H/R) induced pyroptosis. Moreover, GSDMD knockdown protects kupffer cells against H/R induced pyroptosis in vitro. Here, we report, for the first time, that glycyrrhizin attenuated tissue damage and kupffer cells pyroptosis during liver ischemia-reperfusion injury (LIRI) and identify a previously unrecognized HMGB1- dependent GSDMD- mediated signaling pathway in the mechanism of kupffer cells pyroptosis induced by H/R. Our findings provide the first demonstration of GSDMD-determined pyroptotic cell death responsible for I/R induced release of IL-1β and this would provide a mandate to better understand the unconventional mechanisms of cytokine release in the sterile innate immune system.

Topics: Animals; Anti-Inflammatory Agents; Apoptosis Regulatory Proteins; Glycyrrhizic Acid; HMGB1 Protein; Interleukin-1beta; Intracellular Signaling Peptides and Proteins; Kupffer Cells; Liver; Liver Diseases; Male; Mice, Inbred C57BL; Peroxidase; Phosphate-Binding Proteins; Pyroptosis; Reperfusion Injury

Renal ischemia-reperfusion injury (IRI) usually causes acute kidney injury. There is an urgent need to develop an effective agent to prevent renal IRI. This study aimed to examine the effect of butyrate on renal IRI in rats.. Rats were randomly assigned into 3 groups (10 rats in each group): the sham group, the IRI group, and the butyrate group. Rats were injected intravenously with 300 mg/kg of sodium butyrate in the butyrate group and with a saline solution in the sham group and IRI group 30 min before renal ischemia. After 24 h of reperfusion, renal function and histologic damage were examined. Myeloperoxidase (MPO) activity assay, in situ apoptosis examination, enzyme-linked immunosorbent assay, immunohistochemical assay, and Western blot were performed as well.. Butyrate pretreatment significantly reduced renal dysfunction and histologic damage induced by renal IRI. Butyrate pretreatment caused a significant attenuation of neutrophil infiltration, which was reflected by the reduction of renal MPO activity. Butyrate also reduced apoptotic tubular cell death and improved caspase-3 activation. The expression of TNF-α was decreased following butyrate pretreatment.. Butyrate pretreatment protects rats from renal IRI by inhibiting inflammation and apoptosis. Therefore, butyrate may be a potential therapeutic agent for preventing renal IRI.

Topics: Acute Kidney Injury; Animals; Anti-Inflammatory Agents; Apoptosis; Butyrates; Enzyme-Linked Immunosorbent Assay; Immunohistochemistry; Inflammation; Kidney; Male; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

Intestinal ischemia/reperfusion (I/R) injury is a serious clinical event that may induce intestinal mucosal injury, whose major underlying mechanisms include reactive oxygen species (ROS) generation, release of inflammatory mediators and induction of apoptosis. Irisin is considered an agent with potent protection against many pathological injures. The aim of this study was to investigate the protective effect of irisin pretreatment on intestinal injury and explore its underlying mechanisms in a mouse model of intestinal I/R injury as well as a cell model (IEC-6 cell) of hypoxia/reoxygenation (H/R). The results showed that irisin pretreatment ameliorated I/R and H/R-induced injury in vivo and in vitro. In addition, irisin reduced the levels of tumor necrosis factor (TNF)-α, interleukin(IL)-1β and interleukin(IL)-6 in the intestine. Compared with the I/R group, irisin pretreatment effectively reduced malondialdehyde (MDA) and myeloperoxidase (MPO) levels, but increased superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in the intestine, and significantly reduced oxidative stress. Furthermore, irisin pretreatment downregulated Bax and cleaved Caspase-3 at the protein level, and increased Bcl-2 protein amounts, significantly reducing apoptosis in the intestine of I/R mice. Moreover, both in vivo and in vitro results showed that irisin pretreatment significantly upregulated nuclear factor (erythroid-derived 2)-like 2 (Nrf2) protein. Meanwhile, Nrf2 siRNA treatment partially abrogated the protective effects of irisin pretreatment on H/R induced cellular damage, inflammatory response, oxidative stress, and apoptosis in IEC-6 cells. These findings suggest that irisin pretreatment improves I/R-induced intestinal inflammatory response, reduces oxidative stress and inhibits apoptosis, which could be, at least partially, associated with Nrf2 pathway activation.

Topics: Animals; Apoptosis; Cell Line; Cytokines; Fibronectins; Glutathione Peroxidase; Intestinal Diseases; Intestinal Mucosa; Male; Malondialdehyde; Mice, Inbred C57BL; NF-E2-Related Factor 2; Peroxidase; Protective Agents; Rats; Reperfusion Injury; Signal Transduction; Superoxide Dismutase

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal).\ \ This article has been retracted at the request of the Editor-in-Chief and authors.\ \ The authors reported that the paper had been submitted without permission of all authors (specifically Professor Wu). When asked to respond to alleged image manipulation by ‘Hoya camphorifolia’ in Fig. 8B and western blots, they responded that they regret the mistakes in figure 8B and that their technical collaborators could not provide the original images of the Western blots in this paper.\ \ The authors apologise for any misconceptions that this paper may have resulted in.

Topics: Animals; Annexin A1; Apoptosis; Disease Models, Animal; Gene Expression Regulation; Humans; Inflammation; Myocardial Infarction; Myocardial Reperfusion Injury; Myocardium; Neutrophil Infiltration; Neutrophils; Peroxidase; Rats; Reperfusion Injury; Signal Transduction; STAT3 Transcription Factor; Transcriptional Activation; Vascular Endothelial Growth Factor A

Though the cross-induction of either acute kidney (AKI) injury to ischemic stroke (IS) or IS to AKI might not be encountered in the early stages of cerebrorenal syndrome (CRS), both pathologies coexist in late stages. Therefore, we firstly established a late stage CRS rat model by simultaneous induction of both diseases, and further, cerebro and reno-protective activities of human platelet-rich plasma (hPRP), a blood-derived tissue engineering biomaterial, were tested in this pathology. hPRP was administrated via left common carotid artery and abdominal aorta 2 h post-sham procedure in Sprague-Dawley rats. Circulatory inflammatory markers (TNF-α/MPO/IL-6/Ly6G/CD11b/c), histopathologic cerebro and renal changes and oxidative stress were determined. Inflammation, infarct size, brain-associated inflammatory/DNA and mitochondrial damage and oxidative-stress with reduced neurons and neurological function were manifested in CRS group compared to other groups. CRS group also demonstrated declined renal function, accelerated renal collagen deposition, fibrosis and compromised glomerular podocyte components (podocin/ZO-1/fibronectin/synaptopodin). However, hPRP simultaneously suppressed all the inflammatory, cerebral and renal pathologic characteristics. hPRP also inhibited the expression of brain-associated inflammatory/DNA/mitochondrial damage and oxidative-stress biomarkers. These findings imply that hPRP may effectively exert cerebro- and renoprotective activities in late stage CRS through anti-oxidative, anti-inflammatory, anti-DNA and anti-mitochochondrial damaging activities.

Topics: Acute Kidney Injury; Animals; Biocompatible Materials; Blotting, Western; Immunohistochemistry; Inflammation; Interleukin-6; Kidney; Magnetic Resonance Imaging; Male; Oculocerebrorenal Syndrome; Oxidative Stress; Peroxidase; Platelet-Rich Plasma; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

Free jejunal flaps are among the most commonly used flaps for esophageal reconstruction. However, ischemia-reperfusion injury caused by warm ischemia seen during transfer limits their use. Iloprost, a prostacyclin analogue, has been shown to reduce ischemia-reperfusion injury in various organs. The authors investigated tissue damage in jejunal flaps with iloprost and ischemic preconditioning and compared the effectiveness of these two modalities.. Thirty-four Sprague-Dawley rats were randomized into five groups: sham, ischemia-reperfusion (control), ischemic preconditioning, iloprost, and ischemic preconditioning plus iloprost. All flaps, except those in the sham group, underwent ischemia for 60 minutes and reperfusion for 2 hours. Flap perfusion was assessed by laser Doppler perfusion monitoring. Histologic sections were scored using the Chiu scoring system. Superoxide dismutase and myeloperoxidase levels were measured spectrophotometrically.. Animals that were administered iloprost and/or underwent ischemic preconditioning had better postischemic recovery of mesenteric perfusion (ischemic preconditioning, 78 percent; iloprost, 83 percent; ischemic preconditioning plus iloprost, 90 percent; versus ischemia-reperfusion, 50 percent; p < 0.05). All intervention groups showed improved histology of jejunal flaps following ischemia-reperfusion injury (ischemic preconditioning, 3; iloprost, 2.3; ischemic preconditioning plus iloprost, 3.2; versus ischemia-reperfusion, 4.7; p < 0.01, p < 0.001, and p < 0.05, respectively). Superoxide dismutase levels were higher in ischemic preconditioning, iloprost plus ischemic preconditioning, and iloprost groups (ischemic preconditioning, 2.7 ± 0.2; ischemic preconditioning plus iloprost, 2.5 ± 0.3; versus ischemia-reperfusion, 1.2 ± 0.1; p < 0.01; iloprost, 2.4 ± 1.1; versus ischemia-reperfusion, 1.2 ± 0.1; p < 0.05). Myeloperoxidase, a marker for neutrophil infiltration, was lower in the iloprost group (iloprost, 222 ± 5; versus ischemia-reperfusion, 291 ± 25; p < 0.05).. This study showed that both iloprost and ischemic preconditioning reduced reperfusion injury in jejunal flaps. Based on histologic results, iloprost may be a novel treatment alternative to ischemic preconditioning.

Topics: Animals; Antioxidants; Biomarkers; Disease Models, Animal; Esophagus; Free Tissue Flaps; Iloprost; Ischemic Preconditioning; Jejunum; Laser-Doppler Flowmetry; Male; Neutrophil Infiltration; Peroxidase; Platelet Aggregation Inhibitors; Random Allocation; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase

Dexmedetomidine (DEX) can protect the lung from ischemia-reperfusion (I/R) injury, but the underlying mechanisms are not fully understood. The aims of this study were to determine whether DEX attenuates lung injury following lower extremity I/R and to investigate the related toll-like receptor 4 (TLR4) signaling pathway. Twenty-eight SD rats were divided into four groups (n = 7): Sham, I/R, I/R + DEX (25 μg/kg prior to ischemia), and I/R + DEX + Atip (250 μg/kg atipamezole before DEX treatment). Lower extremity I/R was induced by left femoral artery clamping for 3 hours and followed by 2 hours reperfusion. Quantitative alveolar damage and the wet/dry (W/D) ratio were calculated. Interleukin (IL)-1, IL-6, and tumor necrosis factor (TNF)-α in the bronchoalveolar lavage fluid (BALF) and serum and myeloperoxidase (MPO) in the lung were measured. The TLR4 and MyD88 mRNA expression levels were measured by RT-PCR, nuclear factor (NF)-κB, and phosphorylated NF-κB by western blot, respectively. Quantitative alveolar damage, W/D ratio, MPO, BALF and serum IL-1, IL-6, and TNF-α, and TLR4, MyD88, NF-κB, and p-NF-κB expression significantly increased in the I/R group relative to the Sham group. DEX preconditioning significantly reduced lung edema, and histological injury relative to the I/R group. Serum and BALF IL-1, IL-6, and TNF-α levels, MPO activity and TLR4, MyD88, NF-κB, and p-NF-κB expression were also significantly reduced in the I/R + DEX group compared with the I/R group. Atipamezole partially reversed all the aforementioned effects. DEX preconditioning protects the lungs against lower extremity I/R injury via α2-adrenoceptor-dependent and α2-adrenoceptor-independent mechanisms. It also suppresses the TLR4 pathway and reduces inflammation.

Topics: Animals; Bronchoalveolar Lavage Fluid; Cytokines; Dexmedetomidine; Extremities; Lung; Lung Injury; Male; Myeloid Differentiation Factor 88; NF-kappa B; Organ Size; Peroxidase; Rats, Sprague-Dawley; Reperfusion Injury; Signal Transduction; Toll-Like Receptor 4

Intestinal ischemia/reperfusion (I/R) injury is associated with high morbidity and mortality. This study aimed to compare the protective efficacy of intestinal ischemic preconditioning (IIPC) and limb ischemic preconditioning (LIPC) against intestinal I/R injury and investigate their combined protective effect and the underlying mechanism. Male Sprague-Dawley rats were pretreated with IIPC, LIPC, or IIPC plus LIPC (combined), and intestinal I/R or sham operation was performed. The animals were sacrificed at 2 and 24 h after reperfusion and then blood and tissue samples were harvested for further analyses. In additional groups of animals, a 7-day survival study was conducted. The results showed that ischemic preconditioning (IPC) improved the survival rate and attenuated intestinal edema, injury, and apoptosis. IPC decreased the levels of tumor necrosis factor-α, interleukin -6, malondialdehyde and myeloperoxidase, and increased the activity of superoxide dismutase in serum and intestine after the I/R event. IPC downregulated the expression of Toll-like receptor-4 (TLR4) and nuclear factor-kappa B (NF-κB). The effect of combined pretreatment was better than that of single pretreatment in the late phase (24 h), but not in the early phase (2 h). The study demonstrated that IPC could significantly attenuate intestinal injury induced by intestinal I/R via inhibiting inflammation, oxidative stress, and apoptosis. IIPC and LIPC conferred no synergy in protecting I/R-induced intestinal injury in the early phase, but combined preconditioning had clearly stronger protection in the late phase, which was associated with the inhibition of the activated TLR4/NF-κB signaling pathway. It suggested that LIPC or combined preconditioning could potentially be applied in the clinical settings of surgical patient care.

Topics: Amine Oxidase (Copper-Containing); Animals; Apoptosis; Intestinal Mucosa; Ischemic Preconditioning; Male; Malondialdehyde; Mesenteric Ischemia; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Signal Transduction; Superoxide Dismutase; Toll-Like Receptor 4; Tumor Necrosis Factor-alpha

Neutrophil is a significant contributor to ischemia reperfusion (IR) induced liver tissue damage. However, the exact role of neutrophils in IR induced innate immune activation and liver damage is not quite clear. Our study sheds light on the role of chronic oxidative stress end products in worsening the IR inflammatory process by neutrophil recruitment and activation following liver surgery. We employed specific inhibitors for molecular targets-NOX2 (NADPH oxidase 2) and P38 MAPK (Mitogen activated protein kinase) signal to counteract neutrophil activation and neutrophil extracellular trap (NET) release induced liver damage in IR injury. We found that acrolein initiated neutrophil chemotaxis and induced NET release both in vitro and in vivo. Acrolein exposure caused NET induced nuclear and mitochondrial damage in HepG2 cells as well as aggravated the IR injury in rat liver. Pretreatment with F-apocynin and naringin, efficiently suppressed acrolein induced NET release in vitro. Notably, it suppressed the expression of inflammatory cytokines, P38MAPK-ERK activation, and apoptotic signals in rat liver exposed to acrolein and subjected to IR. Moreover, this combination effectively attenuated acrolein induced NET release and hepatic IR injury. In the current study we have shown that the acrolein accumulation in liver due to chronic stress, is responsible for neutrophil recruitment and its activation leading to NET induced liver damage during surgery. Our study shows that therapeutic targeting of NOX2 and P38MAPK signaling in patients with chronic hepatic disorders would improve post operative hepatic function and survival.

Topics: Acetophenones; Acrolein; Animals; Antioxidants; Apoptosis; Cell Death; Cell Nucleus; Chemotaxis; DNA Damage; Enzyme Inhibitors; Extracellular Traps; Flavanones; Hep G2 Cells; Histones; Humans; Inflammation Mediators; Liver; Male; MAP Kinase Signaling System; Mitochondria; NADPH Oxidase 2; Neutrophils; p38 Mitogen-Activated Protein Kinases; Peroxidase; Rats, Wistar; Reperfusion Injury; Respiratory Burst; Tumor Necrosis Factor-alpha

Aortic cross-clamping-induced ischemia-reperfusion (IR) is an important factor in the development of postoperative acute cardiac injury following abdominal aortic surgery. We investigated the possible anti-oxidant/anti-inflammatory effects of fluoxetine (FLX), which is used widely as a preoperative anxiolytic on cardiac injury induced by IR of the infrarenal abdominal aorta. FLX was administered to IR-performed (60 min of ischemia and 120 min of reperfusion) rats for 3 days, once daily at 20 mg/kg i.p. dosage. Results were compared to control and non-FLX-treated IR-performed rats. Serum creatine kinase (CK) and CK-MB levels, lipid hydroperoxide, thiobarbituric acid reactive substances, and pro-oxidant/anti-oxidant balance levels in the IR group were significantly higher whereas superoxide dismutase activity, glutathione, and ferric reducing/anti-oxidant power levels were lower than for the control. IR also increased myeloperoxidase activity, tumor necrosis factor-α, interleukin-1β, and interleukin-6 and decreased interleukin-10 levels. FLX decreased CK, CK-MB, lipid hydroperoxide, thiobarbituric acid reactive substances, and pro-oxidant/anti-oxidant balance levels while increasing superoxide dismutase activity, glutathione, and ferric reducing/anti-oxidant power levels. FLX also decreased myeloperoxidase activity, tumor necrosis factor-α, interleukin-1β, and interleukin-6 levels and increased interleukin-10 levels compared to IR. FLX attenuated the morphological changes associated with cardiac injury. Our study clearly demonstrates that FLX confers protection against aortic IR-induced cardiac injury, tissue leucocyte infiltration, and cellular integrity via its anti-oxidant/anti-inflammatory effects.

Topics: Animals; Antioxidants; Biomarkers; Cardiotonic Agents; Creatine Kinase; Cytokines; Fluoxetine; Hemodynamics; Iron; Lipid Peroxides; Myocardium; Oxidants; Oxidation-Reduction; Oxidative Stress; Peroxidase; Rats, Sprague-Dawley; Reperfusion Injury; Thiobarbituric Acid Reactive Substances

We characterized fetal and placental growth and uterine and placental inflammation in pregnant C3H/HeOuJ and C57BL/6J mice (strains with different sensitivities to metabolic and circulatory pathologies), using different uterine ischemia/reperfusion (I/R) protocols, to establish and refine a murine model of I/R-induced fetal growth restriction (FGR). Pregnant C3H/HeOuJ mice on gestation day 15 were subjected to unilateral uterine I/R by (1) total blood flow restriction (TFR) by occlusion of the right ovarian and uterine arteries for 30 minutes, (2) partial flow restriction (PFR) by occlusion of only the right ovarian artery for 30 minutes, or (3) sham surgery. Pregnant C57BL/6J mice were treated the same, but on gestation day 14 and with TFR for only 5 minutes due to high sensitivity of C57BL/6J mice to I/R. Four days post-I/R, the animals were euthanized to determine fetal and placental weight and fetal loss and to assay placental myeloperoxidase (MPO) activity. In C3H/HeOuJ mice, TFR/30 minutes induced significantly ( P < .05) lower fetal and placental weights and higher placental MPO activity, compared to controls. The PFR/30 minutes produced the same effects except placental weights were not reduced. In contrast, in C57BL/6J mice, TFR for only 5 minutes was sufficient to induce FGR and increase fetal loss; while PFR/30 minutes lowered fetal but not placental weights and increased fetal loss but not placental MPO activity. In summary, we present the first published model of I/R-induced FGR in mice. We find that mice of different strains have differing sensitivities to uterine I/R, therefore differing I/R response mechanisms.

Topics: Animals; Chorioamnionitis; Disease Models, Animal; Female; Fetal Growth Retardation; Fetal Weight; Male; Mice, Inbred C3H; Mice, Inbred C57BL; Organ Size; Peroxidase; Placenta; Pregnancy; Reperfusion Injury; Uterine Cervicitis; Uterus

This study was aimed to investigate the cardioprotective and antioxidant effect of Vaccinium meridionale Swartz in ischemia-induced male albino Wistar strain rats. Rats were grouped into 5 of 6 numbers each. Group I served as a sham, group II served as control and group III, IV, and V served for 1, 10, and 25 mg/kg/d of an extract of Vaccinium meridionale Swartz for 15 consecutive days of treatment. Serum marker enzymes, lipid peroxidation, and myeloperoxidase were increased, whereas antioxidant enzymes were reduced in control due to injury. Increased phenol and anthocyanin contents and increased free radical scavenging activity was noted following treatment. Serum marker enzymes, necrosis, and lipid peroxidation, were reduced, whereas antioxidant enzymes and reduced glutathione were increased. Nitric oxide synthase and Akt expression were also increased following treatment. Taking all these data together, it is suggested that Vaccinium meridionale Swartz may be a potential therapeutic agent for the treatment of ischemic injury.

Topics: Animals; Antioxidants; Biomarkers; Disease Models, Animal; Glutathione; Lipid Peroxidation; Male; Nitric Oxide Synthase; Peroxidase; Plant Extracts; Proto-Oncogene Proteins c-akt; Rats; Rats, Wistar; Reactive Oxygen Species; Reperfusion Injury; Vaccinium

Acute lung injury (ALI) is a common complication after intestinal ischemia and reperfusion (I/R) injury that can lead to acute respiratory distress syndrome (ARDS). We have previously demonstrated that females are protected against lung damage induced by intestinal I/R through an estrogen mediated mechanism.. To investigate the effect of obesity on ALI induced by intestinal I/R in female mice.. C57Bl/6 female mice were fed with a standard low-fat diet (SD) or a high-fat diet (HFD) for 9 weeks. Intestinal I/R injury was induced by a 45 min occlusion of the mesenteric artery followed by 2 and 24 h of reperfusion.. Significant increase in lung myeloperoxidase expression (MPO) and neutrophil numbers of SD and HFD mice occurred at 2 h and 24 h of reperfusion. Furthermore, HFD mice presented a significant increase in lung eosinophil peroxidase (EPO) expression and eosinophil numbers compared to SD mice. Lung wet/dry weight ratio was significantly greater in HFD mice at 2 and 24 h of reperfusion, accompanied by a significant increase in the expression of inducible NO in the lung tissue and a significant decrease in arterial oxygen saturation at 24 h of reperfusion relative to SD mice.. Obesity predisposes female mice to increased pulmonary oedema and deterioration in gas exchange, which is accompanied by an increase in iNOS expression in the lung.

Topics: Acute Lung Injury; Animals; Diet, High-Fat; Disease Models, Animal; Female; Intestines; Mice; Mice, Inbred C57BL; Neutrophils; Nitric Oxide Synthase Type II; Obesity; Peroxidase; Pulmonary Edema; Pulmonary Gas Exchange; Reperfusion Injury; Sex Factors

This study aimed to investigate the anti-inflammatory effect of 4-methylcyclopentadecanone (4-MCPC) in rats suffering from a cerebral ischemia/reperfusion (I/R) injury. In this study, the focal cerebral ischemia in rats was induced by middle cerebral artery occlusion (MCAO) for 2 h, and the rats were treated with 4-MCPC (8 mg/kg) just 0.5 h before reperfusion. The ischemic infarct volume was recorded 24 h after the MCAO. In addition, myeloperoxidase (MPO) activity and TNF-α and IL-1β levels in the ischemic cerebral cortex were determined by ELISA, while nuclear translocation of NF-κB p65 subunit and expression of p-IκBα were investigated by Western blotting. Our results showed that 4-MCPC treatment decreased infarct volume significantly, compared with I/R group (16.8%±7.5% vs. 39.7%±10.9%); it reduced MPO activity (0.43 ± 0.10 vs. 1.00 ± 0.51 U/g) and expression levels of TNF-α (18.90 ± 3.65 vs. 35.87 ± 4.87 ng/g) and IL-1β (1.68 ± 0.23 vs. 2.67 ± 0.38 ng/g) in ischemic brain tissues of rats. Further study revealed that 4-MCPC treatment markedly reduced nuclear translocation of NF-κB p65 subunit and expression of p-IκBα in ischemic cerebral cortex. Taken together, our results suggest that 4-MCPC protects against cerebral I/R injury and displays anti-inflammatory actions through inhibition of the NF-κB signal pathway.

Topics: Animals; Anti-Inflammatory Agents; Cerebral Cortex; Disease Models, Animal; Infarction, Middle Cerebral Artery; Interleukin-1beta; Ketones; Macrocyclic Compounds; Male; Neuroprotective Agents; NF-KappaB Inhibitor alpha; Peroxidase; Phosphorylation; Rats, Sprague-Dawley; Reperfusion Injury; Transcription Factor RelA; Tumor Necrosis Factor-alpha

Ischemia reperfusion injury (IRI) causes postoperative complications and influences the outcome of the patients undergoing liver surgery and transplantation. Postconditioning (PostC) is a known manual conditioning to decrease the hepatic IRI. Here we aimed to optimize the applicable PostC protocols and investigate the potential protective mechanism.. Thirty Sprague-Dawley rats were randomly divided into 3 groups: the sham group (n = 5), standard orthotopic liver transplantation group (OLT, n = 5), PostC group (OLT followed by clamping and re-opening the portal vein for different time intervals, n = 20). PostC group was then subdivided into 4 groups according to the different time intervals: (10 s × 3, 10 s × 6, 30 s × 3, 60 s × 3, n = 5 in each subgroup). Liver function, histopathology, malondialdehyde (MDA), myeloperoxidase (MPO), expressions of p-Akt and endoplasmic reticulum stress (ERS) related genes were evaluated.. Compared to the OLT group, the grafts subjected to PostC algorithm (without significant prolonging the total ischemic time) especially with short stimulus and more cycles (10 s × 6) showed significant alleviation of morphological damage and graft function. Besides, the production of reactive oxidative agents (MDA) and neutrophil infiltration (MPO) were significantly depressed by PostC algorithm. Most of ERS related genes were down-regulated by PostC (10 s × 6), especially ATF4, Casp12, hspa4, ATF6 and ELF2, while p-Akt was up-regulated.. PostC algorithm, especially 10 s × 6 algorithm, showed to be effective against rat liver graft IRI. These protective effects may be associated with its antioxidant, inhibition of ERS and activation of p-Akt expression of reperfusion injury salvage kinase pathway.

Topics: Algorithms; Animals; Constriction; Disease Models, Animal; Endoplasmic Reticulum Stress; Gene Expression Regulation; Ischemic Postconditioning; Liver; Liver Transplantation; Male; Malondialdehyde; Neutrophil Infiltration; Oxidative Stress; Peroxidase; Phosphorylation; Portal Vein; Proto-Oncogene Proteins c-akt; Rats, Sprague-Dawley; Reperfusion Injury; Signal Transduction; Time Factors

This study was aimed to investigate the protective effect of methylene blue against lung injury induced by reperfusion of ischemic hindlimb in a rat model.. Twenty-four healthy adult male Sprague-Dawley rats were equally randomized into three groups: sham (SM) group, ischemia reperfusion (IR) group, and methylene blue (MB) group. Rats in both IR and MB groups were subjected to 4 h of ischemia by clamping the left femoral artery and then followed by 4 h of reperfusion. Treatment with 1% methylene blue (50 mg/kg) was administrated intraperitoneally at 10 min prior to reperfusion in the MB group. After 4 h of reperfusion, malondialdehyde (MDA) level, myeloperoxidase (MPO), and superoxide dismutase (SOD) activities in lung tissue were detected; inflammatory cytokines, including IL-1. Hindlimb IR caused remarkable morphological abnormalities and edema in both muscle and lung tissues. SOD activity was decreased, both the MPO activity and MDA level in lung tissue, as well as IL-1. Methylene blue attenuates lung injury induced by hindlimb IR in rats, at least in part, by inhibiting oxidative stress.

Topics: Animals; Hindlimb; Interleukin-1beta; Interleukin-6; Ischemia; Lung Injury; Male; Methylene Blue; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase

Renal ischemia-reperfusion injury (I/RI) remains a critical clinical situation. Several evidence revealed the potential reno-protective effects of Vitamin D and/or pioglitazone, on renal I/RI. This study addresses the possible involvement of the Wnt4/β-catenin signaling, p-S536NF-κBp65, PPARγ, Ang II/TGF-β, and ACE2 as potential effectors to vitamin D and pioglitazone-mediated renoprotective effects. Two sets of Sprague-Dawley rats (n = 30 rat each), were randomized into sham, I/R, Vit D "alfacalcidol" (5 ng/kg/day), pioglitazone (5 mg/kg/day), and Vit D + pioglitazone groups. In all groups renal biochemical parameters, as well as inflammatory and structural profiles were assessed, besides the expression/contents of Wnt4/β-catenin and pS536-NF-κBp65. All treatments started 7 days before I/RI and animals were killed 24 h after I/RI in the first set, while those in the 2nd set continued their treatments for 14 days. After 24 h, all pre-treatments impeded theI/R effect on neutrophils recruitment, p-S536NF-κBp65, IL-18, NGAL, caspase-3, AngII, ACE-2, PPARγ and TGF-β, besides the expression of Wnt4 and ACE-2 with notable reflection on histological changes. Two weeks after I/RI, except a marked up regulation in Wnt4 expression and a striking elevation in the β-catenin content, the magnitude of the injurious events was relatively less pronounced, an effect that was mostly augmented by the different treatments. The current study pledges a promising and novel reno-protective role of the administration of Vit D and pioglitazone entailing a potential involvement of ICAM-1, MPO, NF-κB, Ang II, ACE2, TGFβ, and a modulation of Wnt4/β-catenin pathway.

Topics: Angiotensin II; Angiotensin-Converting Enzyme 2; Animals; beta Catenin; Cytoprotection; Disease Models, Animal; Hydroxycholecalciferols; Intercellular Adhesion Molecule-1; Interleukin-18; Kidney; Kidney Diseases; Male; Neutrophil Infiltration; NF-kappa B; Peptidyl-Dipeptidase A; Peroxidase; Pioglitazone; Rats, Sprague-Dawley; Reperfusion Injury; Thiazolidinediones; Time Factors; Transforming Growth Factor beta; Wnt Signaling Pathway; Wnt4 Protein

Submandibular gland autotransplantation is an effective approach for treating severe keratoconjunctivitis sicca. However, ischemia/reperfusion (I/R) injury, which inevitably occurs during transplantation, is involved in the hypofunction and structural damage that occur early after transplantation. Therefore, it is critical to identify effective strategies to ameliorate I/R injury in submandibular glands. In this study, we investigated the ability of immediate post-conditioning combined with ischemic preconditioning to attenuate I/R injury. We observed that after I/R injury, the level of reactive oxygen species was increased, inflammatory response was strengthened, and severe apoptosis had occurred. In addition, the salivary flow rate was greatly decreased. However, the pathogenesis of I/R injury was significantly ameliorated by ischemia post-conditioning or ischemia preconditioning treatments. In addition, the combination of ischemia preconditioning and post-conditioning achieved synergistic protective effects against I/R injury compared with ischemia preconditioning or ischemia post-conditioning alone. The secretion function was restored in the combination group. Furthermore, the combination treatment involved the same mechanisms of ischemia preconditioning or ischemia post-conditioning, including suppression of the inflammatory reaction and neutrophil accumulation, attenuation of oxidation stress, and inhibition of apoptosis. In conclusion, the combination of ischemia preconditioning and ischemia post-conditioning treatment is a simple and effective approach for treating I/R injury in submandibular glands.

Topics: Animals; Apoptosis; Blotting, Western; Enzyme-Linked Immunosorbent Assay; In Situ Nick-End Labeling; Ischemic Preconditioning; Lactic Acid; Male; Malondialdehyde; Peroxidase; Rabbits; Random Allocation; Reactive Oxygen Species; Real-Time Polymerase Chain Reaction; Reperfusion Injury; Salivation; Submandibular Gland; Superoxide Dismutase

Cold-inducible RNA-binding protein is a novel damage-associated molecular pattern that causes inflammation. C23, a short peptide derived from cold-inducible RNA-binding protein, has been found to have efficacy in blocking cold-inducible RNA-binding protein's activity. We hypothesized that C23 reduces inflammation and tissue injury induced by intestinal ischemia-reperfusion.. Male C57BL/6 mice were subjected to 60 minutes of intestinal ischemia by clamping the superior mesenteric artery. Immediately after reperfusion, either normal saline (vehicle) or C23 peptide (8 mg/kg body weight) was injected intraperitoneally. Four hours after reperfusion, blood, intestinal, and lung tissues were collected for analysis of inflammatory and tissue injury parameters.. Cold-inducible RNA-binding protein levels in the intestinal tissues were significantly increased following intestinal ischemia-reperfusion. Histologic examination of the intestine revealed a significant reduction in injury score in the C23 group by 48% as compared with the vehicles after intestinal ischemia-reperfusion. The serum levels of lactate dehydrogenase and aspartate aminotransferase were increased in animals that underwent vehicle-treated intestinal ischemia-reperfusion, whereas C23-treated animals exhibited significant reductions by 48% and 53%, respectively. The serum and intestinal tissue levels of tumor necrosis factor α were elevated in vehicle-treated intestinal ischemia-reperfusion mice but decreased by 72% and 69%, respectively, in C23-treated mice. Interleukin-6 mRNA levels in the lungs were reduced by 86% in the C23-treated group in comparison to the vehicle-treated group after intestinal ischemia-reperfusion. Expression of macrophage inflammatory protein 2 and level of myeloperoxidase activity in the lungs were dramatically increased after intestinal ischemia-reperfusion and significantly reduced by 91% and 25%, respectively, in the C23-treated group.. C23 has potential to be developed into a possible therapy for reperfusion injury after mesenteric ischemia and reperfusion.

Topics: Alarmins; Animals; Chemokine CXCL2; Drug Evaluation, Preclinical; Interleukin-6; Lung; Lung Diseases; Male; Membrane Glycoproteins; Mesenteric Ischemia; Mice, Inbred C57BL; Nucleolin; Peroxidase; Phosphoproteins; Receptors, Cell Surface; Reperfusion Injury; RNA-Binding Proteins; Tumor Necrosis Factor-alpha

Oxidative stress plays important roles in intestinal ischemia-reperfusion (II/R) injury, and exploration of effective lead compounds against II/R injury via regulating oxidative stress is necessary. In this study, the effects and possible mechanisms of dioscin against hypoxia-reoxygenation (H/R) injury in IEC-6 cells and II/R injury in mice were investigated. The results showed that dioscin markedly increased cell viability, and reduced ROS level caused by H/R injury in IEC-6 cells. in vivo, dioscin significantly reduced the levels of MDA, MPO and chiu' score, increased SOD level, and improved pathological changes caused by II/R injury in mice. Mechanism investigation showed that dioscin markedly up-regulated the expression levels of Sirt6 by decreasing miR-351-5p levels, decreased the expression levels of p-FoxO3α via activating AMPK, and increased the expression levels of MnSOD and CAT. In addition, miR-351-5p mimic in IEC-6 cells and agomir in mice increased ROS levels and aggravated II/R injury. MiR-351-5p inhibitor in IEC-6 cells and antagomir in mice alleviated these actions by adjusting Sirt6 signal pathway. MiR-351-5p interference experiment further confirmed that dioscin increased Sirt6 expression level by down- regulating miR-351-5p level to inhibit oxidative stress and reduce II/R injury. Furthermore, we also demonstrated that dioscin inhibited the expression level of miR-351-5p via reducing TRBP expression level during the generation of miR-351-5p mature body. Dioscin showed protective effect against II/R injury via adjusting miR- 351-5/Sirt6 signal to reduce oxidative stress, which should be considered as one potent candidate to treat II/R injury. In addition, miR-351-5/Sirt6 could be one effective drug target against II/R injury.

Topics: Animals; Cell Line; Cell Survival; Diosgenin; Intestinal Mucosa; Intestines; Male; Malondialdehyde; Mice, Inbred C57BL; MicroRNAs; Oxidative Stress; Peroxidase; Protective Agents; Rats; Reperfusion Injury; Superoxide Dismutase

Ischemia-reperfusion (I/R) adversely affects the intestinal mucosa. The major mechanisms of I/R are the generation of reactive oxygen species (ROS) and apoptosis. Salvianolic acid A (SalA) is suggested to be an effective antioxidative and antiapoptotic agent in numerous pathological injuries. The present study investigated the protective role of SalA in I/R of the intestine.. Adult male Sprague-Dawley rats were subjected to intestinal I/R injury in vivo. In vitro experiments were performed in IEC-6 cells subjected to hypoxia/ reoxygenation (H/R) stimulation to simulate intestinal I/R. TNF-α, IL-1β, and IL-6 levels were measured using enzyme-linked immunosorbent assay. Malondialdehyde and myeloperoxidase and glutathione peroxidase levels were measured using biochemical analysis. Apoptosis was measured by terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling staining or flow cytometry in vivo and in vitro. The level of reactive oxygen species (ROS) was measured by dichlorodihydrofluorescin diacetate (DCFH-DA) staining. Western blotting was performed to determine the expression of heme oxygenase-1 (HO-1), Nrf2 and proteins associated with apoptosis. The mRNA expressions of Nrf2 and HO-1 were detected by quantitative real-time polymerase chain reaction in vivo and in vitro.. Malondialdehyde level and myeloperoxidase and glutathione peroxidase, TNF-α, IL-1β, and IL-6 levels group in intestinal tissue decreased significantly in the SalA pretreatment groups compared to the I/R group. SalA markedly abolished intestinal injury compared to the I/R group. SalA significantly attenuated apoptosis and increased Nrf2/HO-1 expression in vivo and in vitro. However, Nrf2 siRNA treatment partially abrogated the above mentioned effects of SalA in H/R-induced ROS and apoptosis in IEC-6 cells.. The present study demonstrated that SalA ameliorated oxidation, inhibited the release of pro-inflammatory cytokines and alleviated apoptosis in I/R-induced injury and that these protective effects may partially occur via regulation of the Nrf2/ HO-1 pathways.

Topics: Animals; Apoptosis; Caffeic Acids; Caspase 3; Cytokines; Gene Expression Regulation; Heme Oxygenase-1; Intestinal Mucosa; Intestines; Lactates; Male; Malondialdehyde; NF-E2-Related Factor 2; Oxidative Stress; Peroxidase; Protective Agents; Proto-Oncogene Proteins c-bcl-2; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Reperfusion Injury; Signal Transduction

We aimed to investigate the protective and therapeutic effects of dexpanthenol (DXP) on liver injuries induced by ischemia-reperfusion (IR) in an in vivo rat model.. Thirty-two rats were randomly divided into 4 experimental groups (n = 8 in each group: Sham, IR, DXP, and DXP+IR. DXP (500 mg/kg) was intraperitoneally administered for 30 min before 60 min of ischemia, followed by 60 min of reperfusion to rats in the DXP and DXP+IR groups. All rats were euthanized on day 10 to evaluate immunohistopathological changes as well as tissue levels of oxidants and antioxidants.. IR decreased total glutathione (tGSH) levels in IR group when compared to the Sham group. DXP supplementation to IR group significantly ameliorated tGSH levels (P < .05). IR also elevated myeloperoxidase production compared to the Sham group, whereas DXP treatment prevented these hazardous effects. However, plasma superoxidedismutase, catalase, and malondialdehyde levels did not differ between the DXP+IR than the IR rats. Histologic tissue damage was reduced in the DXP and DXP+IR group.. Liver IR is an inevitable problem during liver surgery. Our results suggested that DXP pretreatment suppressed oxidative stress and increased antioxidant levels in a rat model of liver IR.

Topics: Animals; Antioxidants; Catalase; Disease Models, Animal; Female; Glutathione; Glutathione Peroxidase; Liver; Malondialdehyde; Oxidative Stress; Pantothenic Acid; Peroxidase; Random Allocation; Rats; Rats, Sprague-Dawley; Rats, Wistar; Reperfusion Injury; Vitamin B Complex

Ischemia reperfusion (I/R) injury which inevitably occurs during heart transplantation is the major factor leading to organ failure and graft rejection. In order to develop new therapies to prevent I/R injury, we used both a murine heart transplantation model with 24 hour cold I/R and an in vitro cell culture system to determine whether growth differentiation factor 15 (GDF15) is a protective factor in preventing I/R injury in heart transplantation and to further investigate underlying mechanisms of I/R injury. We found that cold I/R caused severe damage to the endocardium, epicardium and myocardium of heart grafts from wild type C57BL/6 mice, whereas grafts from GDF15 transgenic (TG) mice showed less damage as demonstrated by decreased cell apoptosis/death, decreased neutrophils infiltration and the preservation of the normal structure of the heart. Over-expression of GDF15 reduced expression of phosphorylated RelA p65, pre-inflammatory and pro-apoptotic genes while it enhanced Foxo3a phosphorylation in vitro and in vivo. Over-expression of GDF15 inhibited cell apoptosis/death and reduced neutrophil infiltration. In conclusion, this study, for the first time, demonstrates that GDF15 is a promising target for preventing cold I/R injury in heart transplantation. This study also shows that the resultant protective effects are mediated by the Foxo3 and NFκB signaling pathways.

Topics: Animals; Apoptosis; Cold Ischemia; Cytokines; Forkhead Box Protein O3; Gene Expression; Growth Differentiation Factor 15; Heart Transplantation; Humans; Inflammation Mediators; Male; Mice; Myocytes, Cardiac; Peroxidase; Phosphorylation; Rats; Reperfusion Injury; Signal Transduction

The purpose of this study is to investigate the neurological, biochemical, and histopathologic effects of both the acute and maintenance treatment of curcumin on an experimental spinal cord ischemia-reperfusion injury model in rats.. The animals were randomly divided into 4 groups: (1) Sham, (2) ischemia-reperfusion (IR), (3) curcumin, and (4) solvent. Spinal cord ischemia was induced by clamping the aorta with minivascular clamps at a position just below the left renal artery and just proximal to the aortic bifurcation for 45 min. After 72 hr of reperfusion, neurological function was evaluated with a modified Tarlov score. In spinal cords, malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), and nitric oxide (NO) levels were detected biochemically. Immunohistochemical staining was performed by antibodies against interleukin-6 (IL-6) and myeloperoxidase. Histopathologic changes were examined with hematoxylin and eosin staining.. Although MDA tissue levels were elevated significantly in the IR group compared with the sham group, SOD and GPx levels decreased. After the administration of curcumin, MDA levels in the spinal cord decreased, and SOD and GPx levels increased. Those changes were statistically significant. There was no significance at NO levels. Among all groups, there was no difference in IL-6 and myeloperoxidase immunostaining. Histopathological analysis showed that histopathological changes in the IR group were improved by curcumin treatment. In the curcumin group, neurological outcome scores were significantly better statistically when compared with the IR group.. We believe that curcumin possesses antioxidant, antiproliferative, and anticarcinogenic properties and may be an effective drug for the prevention of spinal cord IR injury in light of the neurologic, biochemical, and histopathological data of this study and published scientific literature.

Topics: Animals; Antioxidants; Curcumin; Disease Models, Animal; Glutathione Peroxidase; Interleukin-6; Malondialdehyde; Neuroprotective Agents; Nitric Oxide; Peroxidase; Rats, Wistar; Reperfusion Injury; Spinal Cord; Spinal Cord Ischemia; Superoxide Dismutase; Time Factors

To examine the possible protective effect of quercetin (QT), which is well known for its antioxidant and protective effects in circumstances of oxidative stress, on urinary bladder tissue in a rat model of ischemia/reperfusion (I/R) injury, which is a known factor for the development of lower urinary tract dysfunction partly mediated by the generation of free radicals causing oxidative damage.. Thirty male Sprague-Dawley rats were subjected to I/R injury through clamping the abdominal aorta for 30 min and then allowing reperfusion for the next 60 min. Quercetin (20 mg/kg; subcutaneously) or vehicle were given before ischemia and just before reperfusion. Findings of the isometric contraction studies in the organ bath and of the histological examinations along with oxidative stress markers were evaluated in bladder tissues.. Increased malondialdehyde (MDA) levels and myeloperoxidase (MPO) activities and decreased glutathione (GSH) levels and superoxide dismutase (SOD) activities in the I/R group were reduced by QT treatment. In the I/R group, pro-apoptotic marker caspase-3 was increased and anti-apoptotic bcl-2 protein was decreased, while QT treatment significantly reversed these parameters. In the I/R group contractile responses of the bladder strips to carbachol were significantly lower than those of the control group, which were reversed by QT treatment.. Quercetin treatment protects bladder tissue contractility against acute I/R injury by decreasing oxidative stress and apoptosis induced by I/R.

Topics: Animals; Antioxidants; Apoptosis; Caspases; Glutathione; Isometric Contraction; Male; Malondialdehyde; Muscle Contraction; Peroxidase; Proto-Oncogene Proteins c-bcl-2; Quercetin; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase; Urinary Bladder

Our study aimed to determine whether antithrombin plays a synergistic role in accentuating the effects of intestinal ischemic preconditioning.. Fifty rats were randomly allocated to 5 groups (10 rats/group) as follows: sham treatment (group 1); ischemia-reperfusion (group 2); ischemic preconditioning followed by ischemia-reperfusion (group 3); antithrombin + ischemia-reperfusion, similar to group 2 but including antithrombin administration (group 4); and antithrombin + ischemic preconditioning, similar to group 3 but including antithrombin administration (group 5). Blood samples and liver specimens were obtained for measurement of cytokines, myeloperoxidase, and malondialdehyde. Liver biopsies were examined by electron microscopy.. Intestinal ischemia-reperfusion induced a remote hepatic inflammatory response as evidenced by the striking increase of proinflammatory cytokines, myeloperoxidase, and malondialdehyde. Tumor necrosis factor-α levels in group 5 (12.48 ± 0.7 pg/mL) were significantly lower than in group 3 (13.64 ± 0.78 pg/mL; P = .014). Mean interleukin 1β was lower in group 5 (9.52 ± 0.67pg/mL) than in group 3 (11.05 ± 1.9 pg/mL; P > .99). Mean interleukin 6 was also significantly lower in group 5 (17.13 ± 0.54 pg/mL) than in group 3 (23.82 ± 1 pg/mL; P ≤ .001). Myeloperoxidase levels were significantly higher in group 3 (20.52 ± 2.26 U/g) than in group 5 (18.59 ± 1.03 U/g; P = .025). However, malondialdehyde levels did not significantly improve in group 5 (4.55 ± 0.46 μmol) versus group 3 (5.17 ± 0.61 μmol; P = .286). Tumor necrosis factor-α, interleukin 6, and myeloperoxidase findings show that antithrombin administration further attenuated the inflammatory response caused by ischemia-reperfusion, suggesting a synergistic effect with ischemic preconditioning. These findings were confirmed by electron microscopy.. The addition of antithrombin to ischemic preconditioning may act to attenuate or prevent damage from ischemia-reperfusion injury by inhibiting the release of cytokines and neutrophil infiltration.

Topics: Animals; Antithrombins; Biomarkers; Combined Modality Therapy; Cytokines; Disease Models, Animal; Hepatitis; Intestinal Diseases; Ischemic Preconditioning; Liver; Malondialdehyde; Mesenteric Artery, Superior; Neutrophil Infiltration; Peroxidase; Rats, Wistar; Reperfusion Injury; Splanchnic Circulation; Time Factors

During transplant surgeries, the lung experiences an ischaemia-reperfusion (I/R)-induced damage identified as a significant cause of morbidity and mortality. However, the mechanisms by which I/R induces leucocyte accumulation and subsequent tissue damage in lung surgeries remain unknown. Therefore, the present study aims to assess the role of monocyte chemotactic protein 1 (MCP-1) and macrophage inflammatory protein 2 (MIP-2) in leucocyte chemotaxis related to lung injury secondary to I/R.. Six pigs were subjected to an orthotopic left caudal lobe lung transplantation with a subsequent 60-min graft reperfusion (Transplant group). In addition, six animals underwent to sham surgery (Sham Group). Plasma samples and lung biopsies were collected before the beginning of pneumonectomy, before starting the reperfusion, and 30 min and 60 min after the beginning of the reperfusion. Plasma levels of intercellular adhesion molecule 1 (ICAM-1) and lung expressions of MCP-1, MIP-2, myeloperoxidase (MPO), and lung oedema were measured.. Lung I/R caused substantial damage observed as pulmonary oedema. The oedema was evident after the ischemic insult and increased after reperfusion. After reperfusion, increased levels of MPO were observed which suggests an activation and infiltration of neutrophils into the lung tissue. After 30 min of reperfusion, MCP-1, MIP-2, and ICAM-1 levels were significantly increased compared to prepneumonectomy levels (p < 0.05) and a further increase was observed after 60 min of reperfusion (p < 0.05).. The present study demonstrates that activated neutrophils, as well as MCP-1, MIP-2, and ICAM-1, are involved in inflammatory response induced by ischaemia-reperfusion-induced lung injury.

Topics: Acute Lung Injury; Animals; Chemokine CCL2; Chemokine CXCL2; Ischemia; Lung Transplantation; Peroxidase; Pneumonectomy; Pulmonary Edema; Reperfusion; Reperfusion Injury; Swine

Salvianolic acid B (SAB) is one the major phytocomponents of Radix Salvia miltiorrhiza and exhibit numerous health promoting properties. The objective of the current study was to examine whether SAB exerts a renoprotective effect by attenuating oxidative stress and inflammatory response through activating phosphatidylinositol 3-kinase/serine-threonine kinase B (PI3K/Akt) signaling pathway in a renal ischemic reperfusion rat model. Forty Sprague-Dawley male rats (250-300 g) were obtained and split into four groups with ten rats in each group. The right kidney of all rats was removed (nephrectomy). The rats of the Control group received only saline (occlusion) and served as a sham control group, whereas rats subjected to ischemic reperfusion (IR) insult by clamping the left renal artery served as a postitive control group. The other 2 groups of rats were pretreated with SAB (20 and 40 mg·kg-1·day-1) for 7 days prior IR induction and served as treatment groups (SAB 20+IR; SAB 40+IR). Renal markers creatinine (Cr) and blood urea nitrogen (BUN) were significantly lower in the groups that received SAB. Pretreatment with SAB appears to attenuate oxidative stress by suppressing the production of lipid peroxidation products like malondialdehyde as well as elevating antioxidant activity. The concentration of inflammatory markers and neutrophil infiltration (myeloperoxidase) were significantly decreased. Meanwhile, PI3K protein expression and pAkt/Akt ratio were significantly upregulated upon supplementation with SAB, indicating its renoprotective activity. Taken together, these results indicate that SAB can therapeutically alleviate oxidative stress and inflammatory process via modulating PI3K/Akt signaling pathway and probably ameliorate renal function and thus act as a renoprotective agent.

Topics: Animals; Benzofurans; Blood Urea Nitrogen; Creatinine; Drugs, Chinese Herbal; Inflammation; Kidney; Lipid Peroxidation; Male; Oxidative Stress; Peroxidase; Phosphatidylinositol 3-Kinases; Protective Agents; Proto-Oncogene Proteins c-akt; Rats, Sprague-Dawley; Reperfusion Injury; Signal Transduction

Cholecystokinin (CCK), as a gastrointestinal hormone, has an important protective role against sepsis or LPS-induced endotoxic shock. We aim to address the role of CCK in hepatic ischemia followed by reperfusion (I/R) injury.. A murine model of 60min partial hepatic ischemia followed by 6h of reperfusion was used in this study. CCK and CCKAR Levels in blood and liver were detected at 3h, 6h, 12h and 24h after reperfusion. Then the mice were treated with CCK or proglumide, a nonspecific CCK-receptor (CCK-R) antagonist. Mice were randomly divided into four groups as follows: (1) sham group, in which mice underwent sham operation and received saline; (2) I/R group, in which mice were subjected to hepatic I/R and received saline; (3) CCK group, in which mice were subjected to hepatic I/R and treated with CCK (400μg/kg); (4) proglumide group (Pro), in which mice underwent hepatic I/R and treated with proglumide (3mg/kg); CCK and proglumide were administrated via tail vein at the moment of reperfusion. Serum AST (sAST) and serum ALT (sALT) were determined with a biochemical assay and histological analysis were performed with hematoxylin-eosin (H&E). Cytokines (IL-1β, IL-6, IL-10, TNF-α) expressions in blood were determined with enzyme-linked immunosorbent assay (ELISA). The MPO (myeloperoxidase) assay were used to measure neutrophils' infiltration into the liver. The apoptotic index (TUNEL-positive cell number/total liver cell number×100%) was calculated to assess hepatocelluar apoptosis. Finally, activation of NF-κB and phosphor-p38 expression in liver homogenates were analyzed with Western Blot (WB).. Our findings showed that 1) CCK and CCK-AR were upregulated in our experimental model over time; 2) Treatment with CCK decreased sAST/sALT levels, inflammatory hepatic injury, neutrophil influx and hepatocelluar apoptosis, while proglumide aggravated hepatic injury.. These findings support our hypothesis and suggest that CCK played a positive role in the ongoing inflammatory process leading to liver I/R injury.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Cholecystokinin; Cytokines; Ischemia; Liver; Male; Mice, Inbred C57BL; NF-kappa B; p38 Mitogen-Activated Protein Kinases; Peroxidase; Receptor, Cholecystokinin A; Receptor, Cholecystokinin B; Reperfusion Injury

Limb ischemia/reperfusion causes inflammation and elicits oxidative stress that may lead to local tissue damage and remote organ such as lung injury. This study investigates pulmonary function after limb ischemia/reperfusion and the protective effect of a lipid emulsion (Intralipid).. Twenty-four rats were divided into three groups: sham operation group (group S), ischemia/reperfusion group (group IR), and lipid emulsion treatment group (group LE). limb ischemia/reperfusion was induced through occlusion of the infrarenal abdominal aorta for 3 h. The microvascular clamp was removed carefully and reperfusion was provided for 3 h.. The mean arterial pressure in group LE was higher than group IR during the reperfusion period (P = 0.024). The heart rate of both group LE and IR are significantly higher than group S during the ischemia period(P < 0.001, P < 0.001, respectively). The arterial oxygen pressure of group LE was significantly higher than group IR (P = 0.003), the arterial carbon dioxide pressure of group LE were lower than that of group IR (P = 0.005). The concentration of plasma interleukin-6, tumor necrosis factor-α and malondialdehyde in group LE were significantly lower than group IR (P < 0.001, P = 0.009 and 0.029, respectively). The plasma superoxide dismutase activity in group LE was significantly higher than group IR (P = 0.029). The myeloperoxidase activity in lung tissues of group LE was significantly less than group IR (P = 0.046). Both muscle and lung in group IR were damaged seriously, whereas lipid emulsion (Intralipid) effectively reversed the damage. In summary, Intralipid administration resulted in several beneficial effects as compared to group IR, such as the pulmonary gas exchange and inflammatory.. The ischemic/reperfusion injury of limb muscles with resultant inflammatory damage to lung tissue can be mitigated by administration of a lipid emulsion (Intralipid, 20%, 5 ml/kg). The mechanisms attenuating such a physiological may be attributed to reduction of the degree of limb injury through a decrease in the release of local inflammatory mediators, a reduction of lipid peroxidation, and a blunting of the subsequent remote inflammatory response.

Topics: Acute Lung Injury; Animals; Cytokines; Emulsions; Fat Emulsions, Intravenous; Lung; Oxidative Stress; Peroxidase; Phospholipids; Rats, Sprague-Dawley; Reperfusion Injury; Soybean Oil; Superoxide Dismutase

Recent studies have demonstrated the neuroprotective and immunomodulatory effects of 1,25-dihydroxyvitamin D3 (calcitriol), but no previous study has examined these effects on spinal cord ischemia/reperfusion (I/R) injury. Therefore, the present study aimed to evaluate whether calcitriol protects the spinal cord from I/R injury.. Rabbits were randomized into four groups of eight animals: group 1 (laparotomy control), group 2 (ischemia control), group 3 (30mg/kg intraperitoneal methylprednisolone at surgery), and group 4 (0.5μg/kg, intraperitoneal calcitriol for 7 days before I/R injury). The rabbits in the laparotomy control group underwent laparotomy only, whereas all rabbits in the other groups were subject to spinal cord ischemia by aortic occlusion for 20min, just caudal to the renal artery. Malondialdehyde and catalase levels, myeloperoxidase and xanthine oxidase activities, and caspase-3 concentrations were analyzed. Finally, histopathological, ultrastructural, and neurological evaluations were performed.. After I/R injury, increases in malondialdehyde levels, myeloperoxidase and xanthine oxidase activities, and caspase-3 concentrations were found (p<0.001 for all); by contrast, catalase levels decreased (p<0.001). Calcitriol pretreatment was associated with lower malondialdehyde levels (p<0.001), reduced myeloperoxidase (serum, p=0.018; tissue, p<0.001) and xanthine oxidase (p<0.001) activities, and caspase-3 concentrations (p<0.001), but increased catalase levels (p<0.001). Furthermore, calcitriol pretreatment was associated with better histopathological, ultrastructural, and neurological scores.. Calcitriol pretreatment provided significant neuroprotective benefits following spinal cord I/R injury.

Topics: Animals; Caspase 3; Catalase; Disease Models, Animal; Male; Malondialdehyde; Methylprednisolone; Peroxidase; Rabbits; Reperfusion Injury; Spinal Cord Ischemia; Vitamin D; Xanthine Oxidase

This study investigated the mechanisms responsible for the neuroprotective effect of sildenafil citrate (SFC) on ischemia-reperfusion spinal cord (SC) injuries. Balloon occlusion of the thoracic aorta was used to induce SC ischemia. The animals (n=30) were separated into three groups: sham, SC injury with saline, and SC injury with 5mg/kg i.p. SFC treatment (SFC). The Basso, Beattie, and Bresnahan (BBB) score was determined to assess neurological function at different time intervals after reperfusion. After 48h, histopathology of the SC was assessed by triphenyltetrazolium chloride (TTC) and Nissl staining. Myeloperoxidase (MPO) activity was estimated using an MPO assay kit. Western blot and ELISA assays were performed to estimate interleukin 1 & 10 (IL-1 & IL-10), tumour necrosis factor α (TNF-α), and nuclear factor (NF-kB) levels in SC tissue homogenates. The study results suggest that treatment with SFC significantly increased neurological function compared with the SC group. In addition, SFC treatment reduced MPO activity compared with the SC group, which subsequently inhibited the infiltration of neutrophils into the SC. There was a significant (p<0.01) decrease in the expression of IL-1 and TNF-α, and an increase in the expression of IL-10 in SFC tissue homogenates compared with SC tissues. Moreover, SFC treatment inhibited the activation of NF-kB in the SC after injury. This study shows that SFC exerts a neuroprotective effect on the SC after ischemia/reperfusion injury by attenuating inflammatory mediators.

Topics: Animals; Disease Models, Animal; Inflammation Mediators; Interleukin-1; Interleukin-10; Male; Neuroprotective Agents; NF-kappa B; Peroxidase; Phosphodiesterase Inhibitors; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Spinal Cord; Spinal Cord Injuries; Spinal Cord Ischemia; Tumor Necrosis Factor-alpha

Quercetin, the active substance of tea, fruits and vegetables, exerts a broad spectrum of pharmacological activities and is considered to have potential therapeutic application. The present study was designed to investigate the beneficial effect of quercetin against experimental ischemia- reperfusion (IR) injury of the small intestine in rats. Quercetin was administrated intraperitoneally 30min before 1h ischemia of superior mesenteric artery with following reperfusion periods lasting 1, 4 and 24h. The male specific pathogen-free Charles River Wistar rats were used (n=45). In acute phase, 4h after start of reperfusion, the quercetin induced a significant decrease in mucosal injury index (p<0.05) accompanied by a significant decrease in cyclooxygenase-2 (COX-2) expression in the epithelial lining of the intestinal villi in comparison with the control group (p<0.01). In the epithelium of the intestinal glands, COX-2 expression resulting from IR injury significantly increased regardless quercetin application (in control group p<0.001; in quercetin group p<0.05), but in quercetin group, significant decrease in it during 24h of reperfusion in a late phase of IR injury was detected (p<0.001). Based on morphology of COX-2 positive cells, the COX-2 positivity was found particularly in goblet cells of the intestinal villi epithelium and enteroendocrine cells respectively, in the glandular epithelium. We concluded that quercetin application attenuated mucosal damage from IR injury by inhibiting neutrophil infiltration which was demonstrated by a lower number of myeloperoxidase positive cells in the lamina propria during both phases of IR injury and the significant decrease in that in a late phase after 24h of reperfusion (p<0.05).

Topics: Animals; Cyclooxygenase 2; Enzyme Induction; Epithelial Cells; Intestinal Mucosa; Intestine, Small; Male; Peroxidase; Quercetin; Rats, Wistar; Reperfusion Injury

Oxidative stress and inflammatory response are major factors causing several tissue injuries in intestinal ischemia and reperfusion (I/R). Agmatine has been reported to attenuate I/R injury of various organs. The present study aims to analyze the possible protective effects of agmatine on intestinal I/R injury in rats.. Four groups were designed: sham control, agmatine-treated control, I/R control, and agmatine-treated I/R groups. IR injury of small intestine was induced by the occlusion of the superior mesenteric artery for half an hour to be followed by a 3-hour-long reperfusion. Agmatine (10mg/kg) was administered intraperitoneally before reperfusion period. After 180min of reperfusion period, the contractile responses to both carbachol and potassium chloride (KCl) were subsequently examined in an isolated-organ bath. Malondialdehyde (MDA), reduced glutathione (GSH), and the activity of myeloperoxidase (MPO) were measured in intestinal tissue. Plasma cytokine levels were determined. The expression of the intestinal inducible nitric oxide synthase (iNOS) was also assessed by immunohistochemistry.. The treatment with agmatine appeared to be significantly effective in reducing the MDA content and MPO activity besides restoring the content of GSH. The treatment also attenuated the histological injury. The increases in the I/R induced expressions of iNOS, IFN-γ, and IL-1α were brought back to the sham control levels by the treatment as well.. Our findings indicate that the agmatine pretreatment may ameliorate reperfusion induced injury in small intestine mainly due to reducing inflammatory response and oxidative stress.

Topics: Agmatine; Animals; Carbachol; Disease Models, Animal; Inflammation; Intestine, Small; Male; Malondialdehyde; Oxidative Stress; Peroxidase; Potassium Chloride; Rats; Rats, Wistar; Reperfusion Injury

Management of cerebral ischemia/reperfusion (I/R) injury is still difficult process today.. Aim of present study was to investigate therapeutic properties of sulfasalazine in cerebral transient I/R injury in rat.. Except Control group (n = 5), 20 Wistar albino rats were allocated for acute and chronic stage investigation of I/R injury, and temporary aneurysm clips were attempted to both internal carotid arteries for thirty min. Four hours later, 40 mg/kg once a day sulfasalazine was administered to animals of SL-A and SL-C groups, orally. Animals were decapitated, following which pyknotic and necrotic neuronal cells, perivascular edema, irregularities of intercellular organization (IIO) of hippocampal regions, and cortical necrotic neurons of parietal lobe were counted or scaled histopathologically. Tissue malonyldialdehyde (MDA), myeloperoxidation (MPO), total nitrite/nitrate (NO), interleukin 1-beta (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) level values were evaluated biochemically.. Sulfasalazine could reduce perivascular edema, IIO, cortical and hippocampal neuronal cell death in both stages. It could decrease MDA in acute stage, but not reduce IL-1β, IL-6, MPO, NO, and TNFα levels. It could increase IL-1β levels in chronic stage but not affect to IL-6, MPO, MDA, NO, TNF-α levels.. Sulfasalazine could improve histopathological architecture of hypoxic tissue in both stages of I/R injury in rat. It could inhibit lipid peroxidation cascades just in acute stage. These results suggested that therapeutic mechanisms of sulfasalazine in cerebral I/R injury should be investigated by using more specific laboratory methods in future studies.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Brain Edema; Brain Ischemia; Cerebral Cortex; Hippocampus; Interleukin-1beta; Interleukin-6; Lipid Peroxidation; Male; Malondialdehyde; Nitric Oxide; Peroxidase; Rats, Wistar; Reperfusion Injury; Sulfasalazine; Tumor Necrosis Factor-alpha

Hypoxia preconditioning has been proven to be an effective method to enhance the therapeutic action of mesenchymal stem cells (MSCs). However, the beneficial effects of hypoxic MSCs in ischemia/reperfusion (I/R) lung injury have yet to be investigated. In this study, we hypothesized that the administration of hypoxic MSCs would have a positive therapeutic impact on I/R lung injury at molecular, cellular, and functional levels.. I/R lung injury was induced in isolated and perfused rat lungs. Hypoxic MSCs were administered in perfusate at a low (2.5×105 cells) and high (1×106 cells) dose. Rats ventilated with a low tidal volume of 6 ml/kg served as controls. Hemodynamics, lung injury indices, inflammatory responses and activation of apoptotic pathways were determined.. I/R induced permeability pulmonary edema with capillary leakage and increased levels of reactive oxygen species (ROS), pro-inflammatory cytokines, adhesion molecules, cytosolic cytochrome C, and activated MAPK, NF-κB, and apoptotic pathways. The administration of a low dose of hypoxic MSCs effectively attenuated I/R pathologic lung injury score by inhibiting inflammatory responses associated with the generation of ROS and anti-apoptosis effect, however this effect was not observed with a high dose of hypoxic MSCs. Mechanistically, a low dose of hypoxic MSCs down-regulated P38 MAPK and NF-κB signaling but upregulated glutathione, prostaglandin E2, IL-10, mitochondrial cytochrome C and Bcl-2. MSCs infused at a low dose migrated into interstitial and alveolar spaces and bronchial trees, while MSCs infused at a high dose aggregated in the microcirculation and induced pulmonary embolism.. Hypoxic MSCs can quickly migrate into extravascular lung tissue and adhere to other inflammatory or structure cells and attenuate I/R lung injury through anti-oxidant, anti-inflammatory and anti-apoptotic mechanisms. However, the dose of MSCs needs to be optimized to prevent pulmonary embolism and thrombosis.

Topics: Animals; Antioxidants; Apoptosis; Biomarkers; Bronchoalveolar Lavage Fluid; Capillaries; Caspase 3; Cell Hypoxia; Cytochromes c; Cytosol; Glutathione; Hemodynamics; Hydrogen Peroxide; Intercellular Adhesion Molecule-1; Leukocyte Count; Lung Injury; Male; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Mitogen-Activated Protein Kinases; NF-kappa B; Organ Size; Peroxidase; Protein Carbonylation; Proto-Oncogene Proteins c-bcl-2; Pulmonary Embolism; Rats, Sprague-Dawley; Reperfusion Injury; Signal Transduction; Thiobarbituric Acid Reactive Substances; Thrombosis; Vascular Cell Adhesion Molecule-1

Reperfusion after ischaemia is detrimental to the tissues. The oxidative stress created and cytokines released are mostly responsible in this process. In this study, ethyl pyruvate, a known agent for its anti-inflammatory and antioxidant properties, was used to investigate the effects on ischaemia/reperfusion injury on skin island flaps in rats.. Sixty rats were randomly distributed in three groups (non-ischaemic, ischaemic and medication groups). Ethyl pyruvate was administered in the medication group with a dose of 50 mg/kg. After 24 h and one week, the animals were sacrificed, and the flaps were analyzed macroscopically, histopathologically, biochemically (total nitrite, malondialdehyde and myeloperoxidase).. Biochemical markers indicating oxidative stress, were found elevated in ischaemic group, whereas medication with ethyl pyruvate significantly reduced these values. There was a significant reduction (P<0.05) in the levels of these markers between ischaemic and medication groups. Ethyl pyruvate improved all the parameters significantly.. Ethyl pyruvate showed strong scavenger activity against reactive oxygen species. It could be a potential candidate to improve the flap viability in reconstructive microsurgery, especially in free tissue transfers. However, more studies are warranted in experimental models to confirm these findings.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Humans; Malondialdehyde; Oxidative Stress; Peroxidase; Pyruvates; Rats; Reperfusion Injury; Skin; Surgical Flaps

Topics: Animals; Caspase 3; Cells, Cultured; Genetic Therapy; Hepatocyte Growth Factor; Humans; Interleukin-10; Lung; Male; Malondialdehyde; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Peroxidase; Proto-Oncogene Proteins c-bcl-2; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

Cyclosporine A (CsA) is known as a neuroprotective agent against cerebral ischemia/reperfusion (I/R) in animal models. However, the significant therapeutic effects of CsA have been observed in high systemic doses or manipulating the blood-brain barrier, resulting in systemic side effects and toxicity. As the liposome nanocarriers have been developed for efficient delivery of peptide and proteins, liposomal CsA (Lipo-CsA) could improve cerebral (I/R) injuries. In this study, the liposomal CsA formulation (CsA at dose of 2.5 mg/kg) was prepared to assess the brain injury outcomes in 90 min middle cerebral artery occlusion (MCAO) stroke model followed by 48 h reperfusion in treating rats. Five minutes after induction of cerebral ischemia in rats, intravenous (iv) administration of Lipo-CsA significantly (P < 0.001) recovered the infarct size, the brain edema, and the neurological activities compared to corresponding control groups following 48 h I/R. In addition, after 48 h cerebral I/R, Lipo-CsA potentially (P < 0.001) inhibited the inflammation responses including MPO activity and tumor necrosis factor-alpha level in comparison to other groups. In conclusion, the results indicate that the low dose of CsA in liposomal formulation is more effective compared to higher dose of free form of CsA in treatment of ischemic brain in rats.

Topics: Animals; Brain Ischemia; Cyclosporine; Disease Models, Animal; Infarction, Middle Cerebral Artery; Inflammation; Liposomes; Male; Nanoparticles; Neuroprotective Agents; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Stroke; Time Factors; Tumor Necrosis Factor-alpha

Oxidative and nitrosative stress-induced endothelial cell damage play an essential role in the pathogenesis of hepatic ischemia-reperfusion (IR) injury. IR is associated with reduced eNOS expression and exacerbated by superimposed stress. NOSTRIN induces intracellular endothelial nitric oxide synthase (eNOS) translocation and inducible nitric oxide synthase (iNOS) increases nitric oxide (NO) production. Our aim was to assess hepatic expression of iNOS, eNOS, and NOSTRIN in IR with or without N-acetylcysteine (NAC) or thymoquinone (TQ) pretreatment and to compare their hepatoprotective effects. Surgical induction of IR was performed by occlusion of hepatic pedicle for 30 min with mini-clamp and reperfused for 30 min. The effects of TQ (20 mg/kg/day) or NAC (300 mg/kg/day) administered orally for 10 days were evaluated by serum ALT and AST, oxidative stress parameters, NO production, and histopathological analysis. Also, localization and expression of iNOS, eNOS, and NOSTRIN were assessed by immunofluorescence. TQ or NAC pretreatment significantly decreased elevated serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and myeloperoxidase (MPO) activities, malondialdehyde (MDA) level, and NO production. In addition, they restored the depleted GSH content and alleviated histopathological changes. Furthermore, they up-regulated eNOS and down-regulated iNOS and NOSTRIN expressions. TQ exerts its hepatoprotective effect, at least in part, by nitric oxide signaling pathway through modulation of iNOS, eNOS, and NOSTRIN expressions as well as suppression of oxidative stress.

Topics: Acetylcysteine; Alanine Transaminase; Animals; Antioxidants; Aspartate Aminotransferases; Benzoquinones; Biomarkers; Cytoprotection; Disease Models, Animal; Glutathione; Lipid Peroxidation; Liver; Liver Diseases; Male; Nitric Oxide; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Oxidative Stress; Peroxidase; Rats, Wistar; Reperfusion Injury; Signal Transduction

This study evaluated the effect of mycophenolate mofetil (MMF) on uterine tissue preservation following ischaemia/reperfusion (I/R) injury. Uterine I/R injury was induced in rats by clamping the lower abdominal aorta and ovarian arteries for 30 min. Group I/R + V (n = 7) received vehicle alone while Group I/R + M (n = 7) received 20 mg/kg/day MMF. Control groups underwent sham surgery and received vehicle (Group C) or 20 mg/kg/day MMF (Group M) (n = 7 for both). Four hours after detorsion, uterine tissue 8-hydroxy-2'-deoxyguanosine (8-OHdG), glutathione, malondialdehyde (MDA), myeloperoxidase (MPO), superoxide dismutase (SOD) and serum ischaemia modified albumin (IMA) concentrations were measured. Histopathological analyses were performed. The I/R + M group showed significant reduction in serum IMA and uterine tissue 8-OHdG, MDA and MPO and significant increase in SOD concentrations compared with the I/R + V group, indicating a protective effect against I/R oxidative damage (P = 0.009, P = 0.006, P = 0.002, P = 0.003 and P = 0.009, respectively). Histopathological evaluation revealed MMF treatment resulted in significantly less tissue and cellular damage and apoptosis compared with the I/R + V group. These results indicate MMF is effective in attenuating uterine tissue damage and preventing apoptosis following uterine I/R injury, probably via anti-inflammatory and anti-oxidative action.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Albumins; Animals; Antibiotics, Antineoplastic; Antioxidants; Aorta, Abdominal; Arteries; Deoxyguanosine; Disease Models, Animal; Female; Glutathione; Immunosuppressive Agents; Mycophenolic Acid; Ovary; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase; Uterus

Methane is part of the gaseous environment of the intestinal lumen. The purpose of this study was to elucidate the bioactivity of exogenous methane on the intestinal barrier function in an antigen-independent model of acute inflammation.. Anesthetized rats underwent sham operation or 45-min occlusion of the superior mesenteric artery. A normoxic methane (2.2%)-air mixture was inhaled for 15 min at the end of ischemia and at the beginning of a 60-min or 180-min reperfusion. The integrity of the epithelial barrier of the ileum was assessed by determining the lumen-to-blood clearance of fluorescent dextran, while microvascular permeability changes were detected by the Evans blue technique. Tissue levels of superoxide, nitrotyrosine, myeloperoxidase, and endothelin-1 were measured, the superficial mucosal damage was visualized and quantified, and the serosal microcirculation and mesenteric flow was recorded. Erythrocyte deformability and aggregation were tested in vitro.. Reperfusion significantly increased epithelial permeability, worsened macro- and microcirculation, increased the production of proinflammatory mediators, and resulted in a rapid loss of the epithelium. Exogenous normoxic methane inhalation maintained the superficial mucosal structure, decreased epithelial permeability, and improved local microcirculation, with a decrease in reactive oxygen and nitrogen species generation. Both the deformability and aggregation of erythrocytes improved with incubation of methane.. Normoxic methane decreases the signs of oxidative and nitrosative stress, improves tissue microcirculation, and thus appears to modulate the ischemia-reperfusion-induced epithelial permeability changes. These findings suggest that the administration of exogenous methane may be a useful strategy for maintaining the integrity of the mucosa sustaining an oxido-reductive attack.

Topics: Administration, Inhalation; Animals; Capillary Permeability; Disease Models, Animal; Endothelin-1; Ileum; Immunohistochemistry; Intestinal Mucosa; Male; Mesenteric Artery, Superior; Methane; Oxidative Stress; Peroxidase; Random Allocation; Rats; Rats, Sprague-Dawley; Reference Values; Reperfusion Injury

Experimental study.. To investigate the effect of pre-treatment with PMX53, a C5aR antagonist, on spinal cord ischemia-reperfusion injury (IRI) in rat.. Department of Neurosurgery, Second Affiliated Hospital, Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi Province, China.. IRI was induced in the lumbar spinal cord by applying a mini aneurysm clamp to the abdominal aorta for 60 min in adult Sprague-Dawley rats. PMX53 (1 mg kg(-1)) was administered through femoral vein injection 30 min before ischemia on the rats in the PMX53 group (n=18). The saline group (n=18) was given saline at the same volume through femoral vein injection. The neurologic outcome of the posterior limbs was assessed by the Basso-Beattie-Bresnahan (BBB) score at 1, 6, 12, 24 and 48 h after reperfusion. Histologic changes of the spinal cord were detected with hematoxylin-eosin (H-E) staining. Enzyme-linked immunosorbent assay (ELISA) was used to detect myeloperoxidase (MPO) activity in the spinal cord. Immunohistochemistry was used to investigate the quantity of activated astrocytes and microglia.. After pre-treatment with PMX53, neurologic function improved gradually after 6, 12, 24 and 48 h reperfusion. The BBB score of the PMX53 group increased significantly (P<0.05) compared with the saline group. H-E staining showed that pathologic damage in the PMX53 group was reduced. Moreover, administration of PMX53 significantly inhibited neutrophil infiltration in the spinal cord. Levels of MPO activity in the spinal cord were remarkably lower in the PMX53 group (P<0.05). There were also more activated microglia and astrocytes in the spinal cord of the PMX53 group than in the saline group (P<0.05).. PMX53 delivered 30 min prior to ischemic injury protects the spinal cord from IRI, probably via the inhibition of neutrophil activity, increased activated microglia and astrocyte.

Topics: Analysis of Variance; Animals; Calcium-Binding Proteins; Drug Administration Schedule; Glial Fibrillary Acidic Protein; Immunologic Factors; Microfilament Proteins; Nervous System Diseases; Neurologic Examination; Peptides, Cyclic; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Severity of Illness Index; Spinal Cord; Spinal Cord Injuries; Time Factors

Bradykinin (BK) is used in different tissues. Dose-dependent studies have demonstrated that low doses protect against ischemia/reperfusion (I/R) injury while higher doses lead to adverse effects. Although the beneficial effects of BK infusion were observed in myocardium, its role on the I/R impact in skeletal muscle (SM) has not been fully clarified.. This study was carried out to evaluate the effects of BK, administered in the hindlimbs of rats subjected to I/R.. The study design included three experimental groups: Group 1 control (saline), Group 2 (bradykinin), and Group 3 (HOE 140, a BK2 receptor blocker). In all three groups, rats were subjected to hindlimb ischemia for a total of 2 h followed by continuous 4 h of reperfusion with pharmacological interventions. The methods include analysis of enzymes (lactate dehydrogenase-LDH and creatinine phosphokinase-CPK), cell membrane marker of injury (malondialdeyde-MDA), recruitment of neutrophils (myeloperoxidase-MPO), and apoptosis index (immunohistochemistry TUNEL in situ peroxidase dead end).. Except for the apoptotic index, all parameters studied were shown to be elevated in the reperfusion group intervened with BK. The blocking of BK2 receptors by HOE 140 did not affect the I/R injury.. After 2 h of total ischemia, infusion of bradykinin during 4 h of reperfusion, worsened the I/R injury in the hindlimb skeletal muscle.

Topics: Animals; Apoptosis; Bradykinin; Bradykinin B2 Receptor Antagonists; Creatine Kinase; Hindlimb; L-Lactate Dehydrogenase; Male; Malondialdehyde; Muscle, Skeletal; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Vasodilator Agents

In this study, we investigated the alterations of matrix metalloproteinase (MMP) and tissue inhibitors of metalloproteinases (TIMPs), acute inflammation, and oxidative damage in the circulatory system and the intestine in response to mesenteric ischemia/reperfusion (I/R).. Twenty-one rats were divided randomly into the following three groups (n = 7 in each group): a sham group (CG), an ischemic group (IG), and an I/R group (I/RG). MMP-9, TIMP-1, and myeloperoxidase (MPO) were measured using the enzyme-linked immunosorbent assay method, and lipid peroxidation (quantified as thiobarbituric acid reactive substances (TBARS) content), ischemia-modified albumin, the prooxidant-antioxidant balance (PAB), and ferric-reducing antioxidant power (FRAP) were measured spectrophotometrically. The degree of intestinal injury was evaluated according to the Chiu scoring system.. A significant difference between the mean serum TIMP-1 and MMP-9 levels and the alanine transaminase activity was found among the groups. Compared with the I/RG group a significant difference in the mean tissue MMP-9, MPO, and TBARS levels in addition to the PAB and FRAP was found between the CG and IG groups. The level of MMP-9 also demonstrated a strong, positive, and valid correlation with the TBA-RS levels. A significant morphological change was observed in both the IG and the I/RG groups. The degree of intestinal injury was more severe in the I/R group and was characterized by either villous denudation or villous loss.. These results suggest that MMP-9, TIMP-1, MPO, and oxidative stress may be important in the intestinal injury development that is induced by acute mesenteric I/R in a rat model. MMP-9 overexpression may increase the extent of intestinal villous loss, particularly when MMP-9 is upregulated by the TBARS present in the intestinal injury.

Topics: Animals; Intestinal Mucosa; Lipid Peroxidation; Male; Matrix Metalloproteinase 9; Mesenteric Arteries; Oxidative Stress; Peroxidase; Rats, Sprague-Dawley; Reperfusion Injury; Splanchnic Circulation; Tissue Inhibitor of Metalloproteinase-1

Inflammation-associated oxidative stress contributes to hepatic ischemia/reperfusion injury (IRI). Detrimental inflammatory event cascades largely depend on activated Kupffer cells (KCs) and neutrophils, as well as proinflammatory cytokines, including tumor necrosis factor α (TNF-α) and interleukin (IL) 18. The aim of our study was to evaluate the effects of IL 18 binding protein (IL 18Bp) in hepatic IRI of mice. Thirty C57BL/6 mice were allocated into 3 groups: sham operation, ischemia/reperfusion (I/R), and I/R with intravenous administration of IL 18Bp. Hepatic ischemia was induced for 30 minutes by Pringle's maneuver. After 120 minutes of reperfusion, mice were euthanized, and the liver and blood samples were collected for histological, immunohistochemical, molecular, and biochemical analyses. I/R injury induced the typical liver pathology and upregulated IL-18 expression in the liver of mice. Binding of IL 18 with IL 18Bp significantly reduced the histopathological indices of I/R liver injury and KC apoptosis. The I/R-induced increase of TNF-α, malondialdehyde, aspartate aminotransferase, and alanine aminotransferase levels was prevented in statistically significant levels because of the pretreatment with IL 18Bp. Likewise, blocking of IL 18 ablated the I/R-associated elevation of nuclear factor kappa B, c-Jun, myeloperoxidase, and IL 32 and the up-regulation of neutrophils and T-helper lymphocytes. Administration of IL 18Bp protects the mice liver from I/R injury by intervening in critical inflammation-associated pathways and KC apoptosis.

Topics: Alanine Transaminase; Animals; Apoptosis; Aspartate Aminotransferases; Cytokines; DNA Primers; Gene Expression Regulation; Immunohistochemistry; Inflammation; Intercellular Signaling Peptides and Proteins; Interleukin-18; Liver; Liver Diseases; Liver Transplantation; Male; Malondialdehyde; Mice; Mice, Inbred C57BL; Models, Animal; Neutrophils; Oxidative Stress; Peroxidase; Reperfusion Injury; Signal Transduction; Tumor Necrosis Factor-alpha; Up-Regulation

Complex regional pain syndrome type 1 (CRPS1) may be evoked by ischemia/reperfusion, eliciting acute and chronic pain that is difficult to treat. Despite this, the underlying mechanism of CRPS1 has not been fully elucidated. Therefore, the goal of this study is to evaluate the involvement of inflammation, oxidative stress, and the transient receptor potential ankyrin 1 (TRPA1) channel, a chemosensor of inflammation and oxidative substances, in an animal model of chronic post-ischemia pain (CPIP). Male Wistar rats were subjected to 3 h hind paw ischemia/reperfusion (CPIP model). Different parameters of nociception, inflammation, ischemia, and oxidative stress were evaluated at 1 (acute) and 14 (chronic) days after CPIP. The effect of a TRPA1 antagonist and the TRPA1 immunoreactivity were also observed after CPIP. In the CPIP acute phase, we observed mechanical and cold allodynia; increased levels of tumor necrosis factor-α (hind paw), ischemia-modified albumin (IMA) (serum), protein carbonyl (hind paw and spinal cord), lactate (serum), and 4-hydroxy-2-nonenal (4-HNE, hind paw and spinal cord); and higher myeloperoxidase (MPO) and N-acetyl-β-D-glucosaminidase (NAGase) activities (hind paw). In the CPIP chronic phase, we detected mechanical and cold allodynia and increased levels of IMA (serum), protein carbonyl (hind paw and spinal cord), and 4-HNE (hind paw and spinal cord). TRPA1 antagonism reduced mechanical and cold allodynia 1 and 14 days after CPIP, but no change in TRPA1 immunoreactivity was observed. Different mechanisms underlie acute (inflammation and oxidative stress) and chronic (oxidative stress) phases of CPIP. TRPA1 activation may be relevant for CRPS1/CPIP-induced acute and chronic pain.

Topics: Acetylglucosaminidase; Acute Pain; Aldehydes; Animals; Chronic Pain; Cold Temperature; Hindlimb; Hyperalgesia; Lactic Acid; Male; Nociception; Oxidative Stress; Peroxidase; Protein Carbonylation; Rats; Rats, Wistar; Reflex Sympathetic Dystrophy; Reperfusion Injury; Serum Albumin; TRPA1 Cation Channel; TRPC Cation Channels; Tumor Necrosis Factor-alpha

We examine whether BML-111, a lipoxin receptor agonist, inhibits renal ischemia/reperfusion (I/R) injury, and whether peroxisome proliferator-activated receptor-α (PPARα) or heme oxygenase-1 (HO-1) is involved in protective effects of BML-111 on kidney against I/R injury. Rats subjected to renal I/R injury were treated with or without BML-111. Renal histological and immunohistochemical studies were performed. Expressions of phosphorylated p38 mitogen-activated protein kinase (pp38 MAPK), phosphorylated PPARα (pPPARα), and HO-1 were assessed in NRK-52E cells exposed to BML-111. The binding activity of PPARα to peroxisome proliferator-responsive element (PPRE) on HO-1 promoter in the cells was determined. BML-111 treatment resulted in a marked reduction in the severity of histological features of renal I/R injury, and attenuated the rise in renal myeloperoxidase and malondialdehyde, blood urea nitrogen and creatinine, urinary N-acetyl-β-glucosaminidase, and leucine aminopeptidase levels caused by I/R injury. BML-111 stimulated the renal expressions of pPPARα and HO-1, and cellular messenger RNA (mRNA) and protein expressions of pPPARα and HO-1 which were both blocked by GW6471, a selective PPARα antagonist, and ZnPP-IX, a specific inhibitor of HO-1 pretreatment. The pp38 MAPK inhibitor SB203580 blocked the BML-111-induced expressions of pp38 MAPK, pPPARα, and HO-1 in NRK-52E cells. The binding activity of PPARα to PPRE in nuclear extracts of NRK-52E cells was enhanced by treatment of the cells with BML-111, and was suppressed by GW6471 and SB203580. BML-111 protects the kidney against I/R injury via activation of p38 MAPK/PPARα/HO-1 pathway.

Topics: Acute Kidney Injury; Animals; Blood Urea Nitrogen; Cell Line; Creatinine; Glucuronidase; Heme Oxygenase-1; Heptanoic Acids; Imidazoles; Leucyl Aminopeptidase; Male; Malondialdehyde; Oxazoles; p38 Mitogen-Activated Protein Kinases; Peroxidase; Phosphorylation; PPAR alpha; Promoter Regions, Genetic; Protoporphyrins; Pyridines; Rats; Rats, Sprague-Dawley; Receptors, Lipoxin; Reperfusion Injury; RNA, Messenger; Tyrosine

Inflammatory process mediated by innate and adaptive immune systems is a major pathogenic mechanism of renal ischemia-reperfusion injury (IRI). There are concerns that organ recipients may be at increased risk of developing IRI after receiving kidneys from elder donors. To reveal the effects of aging on the development of renal IRI, we compared the immunologic micromilieu of normal and postischemic kidneys from mice of three different ages (9 wk, 6 mo, and 12 mo). There was a higher number of total T cells, especially effector memory CD4/CD8 T cells, and regulatory T cells in the normal kidneys of old mice. On day 2 after IRI, the proportion of necrotic tubules and renal functional changes were comparable between groups although old mice had a higher proportion of damaged tubule compared with young mice. More T cells, but less B cells, trafficked into the postischemic kidneys of old mice. The infiltration of NK T cells was similar across the groups. Macrophages and neutrophils were comparable between groups in both normal kidneys and postischemic kidneys. The intrarenal expressions of TNF-α and VEGF were decreased in normal and postischemic kidneys of aged mice. These mixed effects of aging on lymphocytes and cytokines/chemokines were not different between the two groups of old mice. Our study demonstrates that aging alters the intrarenal micromilieu but has small effects on the development of initial renal injury after IRI. Further study investigating aging-dependent differences in the repair process of renal IRI may be required.

Topics: Acute Kidney Injury; Aging; Animals; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Interleukin-6; Kidney; Kidney Function Tests; Kidney Tubules; Leukocyte Common Antigens; Male; Mice; Mice, Inbred C57BL; Necrosis; Peroxidase; Reperfusion Injury; Tumor Necrosis Factor-alpha; Vascular Endothelial Growth Factor A

Skeletal muscle ischemia reperfusion accounts for high morbidity and mortality, and cyclooxygenase (COX)-2 is implicated in causing muscle damage. Downregulation of aquaporin-1 (AQP-1) transmembrane protein is implicated in skeletal muscle ischemia reperfusion induced remote lung injury. The expression of COX-2 in lung tissue and the effect of COX-2 inhibition on AQP-1 expression and lung injury during skeletal muscle ischemia reperfusion are not known. We investigated the role of COX-2 in lung injury induced by skeletal muscle ischemia reperfusion in rats and evaluated the effects of NS-398, a specific COX-2 inhibitor.. Twenty-four Sprague Dawley rats were randomized into 4 groups: sham group (SM group), sham+NS-398 group (SN group), ischemia reperfusion group (IR group) and ischemia reperfusion+NS-398 group (IN group). Rats in the IR and IN groups were subjected to 3h of bilateral ischemia followed by 6h of reperfusion in hindlimbs, and intravenous NS-398 8 mg/kg was administered in the IN group. In the SM and SN groups, rubber bands were in place without inflation. At the end of reperfusion, myeloperoxidase (MPO) activity, COX-2 and AQP-1 protein expression in lung tissue, PGE2 metabolite (PGEM), tumor necrosis factor (TNF)-α and interleukin (IL)-1β levels in bronchoalveolar lavage (BAL) fluid were assessed. Histological changes in lung and muscle tissues and wet/dry (W/D) ratio were also evaluated.. MPO activity, COX-2 expression, W/D ratio in lung tissue, and PGEM, TNF-α and IL-1β levels in BAL fluid were significantly increased, while AQP-1 protein expression downregulated in the IR group as compared to that in the SM group (P<0.05). These changes were remarkably mitigated in the IN group (P<0.05). NS-398 treatment also alleviated histological signs of lung and skeletal muscle injury.. COX-2 protein expression was upregulated in lung tissue in response to skeletal muscle ischemia reperfusion. COX-2 inhibition may modulate pulmonary AQP-1 expression and attenuate lung injury.

Topics: Animals; Aquaporin 1; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Interleukin-1beta; Lung; Lung Injury; Muscle, Skeletal; Nitrobenzenes; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sulfonamides; Tumor Necrosis Factor-alpha

The aim of the current study was to investigate whether intestinal ischemic preconditioning (IP) reduces damage to the liver during hepatic ischemia reperfusion (IR). Sprague Dawley rats were used to model liver IR injury, and were divided into the sham operation group (SO), IR group and IP group. The results indicated that IR significantly increased Bax, caspase 3 and NF‑κBp65 expression levels, with reduced expression of Bcl‑2 compared with the IP group. Compared with the IR group, the levels of AST, ALT, MPO, MDA, TNF‑α and IL‑1 were significantly reduced in the IP group. Immunohistochemistry for Bcl‑2 and Bax indicated that Bcl‑2 expression in the IP group was significantly increased compared with the IR group. In addition, IP reduced Bax expression compared with the IR group. The average liver injury was worsened in the IR group and improved in the IP group, as indicated by the morphological evaluation of liver tissues. The present study suggested that IP may alleviates apoptosis, reduce the release of pro‑inflammatory cytokines, ameloriate reductions in liver function and reduce liver tissue injury. To conclude, IP provided protection against hepatic IR injury.

Topics: Alanine Transaminase; Animals; Apoptosis Regulatory Proteins; Aspartate Aminotransferases; Interleukin-1beta; Intestines; Ischemia; Ischemic Preconditioning; Liver; Male; Malondialdehyde; Peroxidase; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

To investigate the effects of perfluorocarbon and ligustrazine in protecting the lungs against ischemia-reperfusion injury in rats.. Forty SD rats with ischemia-reperfusion lung injury were randomized equally into control, ligustrazine, perfluorocarbon, and perfluorocarbon plus ligustrazine groups and received the corresponding treatment via the tail vein 5 min before reperfusion. The lung tissues were harvested and the levels of malondialdehyde (MDA), myeloperoxidase (MPO), superoxide dismutase (SOD) and tumor necrosis factor-α (TNF-α) were detected 3 h after reperfusion. The pathological changes and pathological scores of the lung tissues were analyzed.. MDA and MPO levels were significantly lower and SOD activities significantly higher in the lung tissues in the 3 treatment groups than in the control group (P<0.05). The rats in the combined treatment group showed a significantly lower MPO level and a significantly higher SOD activity than those treated with ligustrazine or perfluorocarbon alone (P<0.05). No significant difference was found in TNF-α levels in the lung tissues among the 4 groups (P>0.05). The lung tissues in the control group showed obvious edema and exudation, and the tissues in ligustrazine and perfluorocarbon groups showed no edema but with a few red blood cells and exudation; no edema was found in the combined treatment group with only a small amount of exudation. The pathological scores differed significantly among the 4 groups.. Perfluorocarbon and ligustrazine, especially in combined use, can promote endogenous oxygen free radical scavenging, decrease peripheral blood proinflammatory cytokines, and inhibit neutrophils filtration in the lungs of rats with ischemia/reperfusion lung injury.

Topics: Animals; Cytokines; Fluorocarbons; Lung Injury; Malondialdehyde; Peroxidase; Protective Agents; Pyrazines; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase; Tumor Necrosis Factor-alpha

To investigate the mechanism of how vacuum sealing drainage (VSD) ameliorating ischemia reperfusion (I/R) injury in skeletal muscle I/R model.. Thirty New Zealand white rabbits were divided into three groups: control (sham operation) group, I/R group, VSD+ I/R group.The ischemia of the left hind limb of the animal was induced by clamping the common femoral artery and vein. After 4 hours of ischemia, the clamp was removed and the hind limp underwent 6 hours reperfusion. VSD treated animals received the treatment at the beginning of reperfusion. The concentrations of myeloperoxidase (MPO), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) in muscular tissues were assayed. HE stained pathological section was used to evaluate the degree of edema of muscular tissues, and the immunohistochemistry was used to detect the percentage of positive cells expressing high mobility group protein B1 (HMGB1). Q-RT-PCR and Western Blot were used to detect the mRNA levels and protein expression of HMGB1 in myocyte respectively. The experimental data was tested using variance analysis.. The levels of inflammatory factors and antioxidant factors in muscular tissues were significantly different in the I/R group compared to the VSD group and control group (the levels of MPO in I/R group, I/R+ VSD group and control group were 0.91±0.22, 0.53±0.08, 0.31±0.10, respectively, F=26.48, P=0.000; MDA were 2.04±0.92, 1.65±1.02, 1.01±0.12, F=4.250, P=0.040; SOD were 35.97±9.23, 55.99±18.97, 61.83±14.91, F=5.240, P=0.020; CAT were 31.42±16.27, 48.50±17.86, 75.95±13.09, F=9.720, P=0.002; GSH were 1.48±0.90, 3.54±1.88, 3.84±2.08, F=5.240, P=0.020). HE staining showed an increased intercellular space ratio in the I/R group (F=16.47, P<0.05). Immunohistochemistry staining showed that percentage of HMGB1 positive myocytes in control, I/R and I/R+ VSD group are 1.94%, 18.63% and 61.36%, respectively. There was significant difference among groups (F=853.886, P<0.01). A significantly inhibited HMGB1 expression by VSD therapy was also validated by the results of Q-RT-PCR (F=50.653, P<0.01) and Western blot (F=963.489, P<0.01).. The results from the present research suggest that VSD may attenuate skeletal muscles I/R injury by increasing the cellular antioxidative stress reaction and inhibiting the reactive oxygen species as well as the inflammatory mediators.

Topics: Animals; Antioxidants; Catalase; Drainage; HMGB1 Protein; Malondialdehyde; Muscle, Skeletal; Oxidative Stress; Peroxidase; Rabbits; Reperfusion Injury; Superoxide Dismutase; Vacuum

To investigate the potential effects of pretreatment with allopurinol on renal ischemia/reperfusion injury (IRI) in a rat model.. Twenty four rats were subjected to right kidney uninephrectomy were randomly distributed into the following three groups (n=8): Group A (sham-operated group); Group B (ischemic group) with 30 min of renal ischemia after surgery; and Group C (allopurinol + ischemia group) pretreated with allopurinol at 50 mg/kg for 14 days. At 72 h after renal reperfusion, the kidney was harvested to assess inflammation and apoptosis.. Pretreatment with allopurinol significantly improved renal functional and histological grade scores following I/R injury (p<0.05). Compared with Group B, the expression levels of caspase-3 and Bax were markedly reduced in Group C, meanwhile, whereas expression of bcl-2 was clearly increased (p<0.05). A newly described marker of inflammation, High Mobility Group Box 1(HMGB1), showed reduced expression in Group C (p<0.05).. Pretreatment with allopurinol had a protective effect on kidney ischemia/reperfusion injury, which might be related to the inhibition of HMGB1 expression.

Topics: Allopurinol; Animals; Apoptosis; Blood Urea Nitrogen; Disease Models, Animal; HMGB1 Protein; Inflammation; Ischemic Preconditioning; Kidney; Male; Peroxidase; Protective Agents; Random Allocation; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase

Evidence suggests that light and circadian rhythms profoundly influence the physiologic capacity with which an organism responds to stress. However, the ramifications of light spectrum on the course of critical illness remain to be determined. Here, we show that acute exposure to bright blue spectrum light reduces organ injury by comparison with bright red spectrum or ambient white fluorescent light in two murine models of sterile insult: warm liver ischemia/reperfusion (I/R) and unilateral renal I/R. Exposure to bright blue light before I/R reduced hepatocellular injury and necrosis and reduced acute kidney injury and necrosis. In both models, blue light reduced neutrophil influx, as evidenced by reduced myeloperoxidase (MPO) within each organ, and reduced the release of high-mobility group box 1 (HMGB1), a neutrophil chemotactant and key mediator in the pathogenesis of I/R injury. The protective mechanism appeared to involve an optic pathway and was mediated, in part, by a sympathetic (β3 adrenergic) pathway that functioned independent of significant alterations in melatonin or corticosterone concentrations to regulate neutrophil recruitment. These data suggest that modifying the spectrum of light may offer therapeutic utility in sterile forms of cellular injury.

Topics: Animals; Color; Color Therapy; Corticosterone; Dose-Response Relationship, Radiation; HMGB1 Protein; Kidney Function Tests; Liver Function Tests; Male; Melatonin; Mice; Mice, Inbred C57BL; Peroxidase; Radiation Dosage; Reperfusion Injury; Severity of Illness Index; Treatment Outcome

The aim of this study was to observe the therapeutic effect of insulin-loaded linear poly(ethylene glycol)-brush-like poly(l-lysine) block copolymer poly(ethylene glycol)-b-(poly(ethylenediamine l-glutamate)-g-poly(l-lysine)) (PEG-b-(PELG-g-PLL) on renal ischemia/reperfusion-induced lung injury through downregulating hypoxia-inducible factor (HIF) as compared to free insulin. Sprague Dawley rats were pretreated with 30 U/kg insulin or insulin/PEG-b-(PELG-g-PLL) complex, and then subjected to 45 minutes of ischemia and 24 hours of reperfusion. The blood and lungs were collected, the level of serum creatinine and blood urea nitrogen were measured, and the dry/wet lung ratios, the activity of superoxide dismutase and myeloperoxidase, the content of methane dicarboxylic aldehyde and tumor necrosis factor-α, and the expression of HIF-1α and vascular endothelial growth factor (VEGF) were measured in pulmonary tissues. Both insulin and insulin/PEG-b-(PELG-g-PLL) preconditioning improved the recovery of renal function, reduced pulmonary oxidative stress injury, restrained inflammatory damage, and downregulated the expression of HIF-1α and VEGF as compared to ischemia/reperfusion group, while insulin/PEG-b-(PELG-g-PLL) significantly improved this effect.

Topics: Animals; Blood Urea Nitrogen; Cell Survival; Creatinine; Hypoxia-Inducible Factor 1, alpha Subunit; Insulin; Ischemia; Kidney; Lung; Lung Injury; Male; Malondialdehyde; Molecular Weight; Organ Size; Particle Size; Peroxidase; Polyethylene Glycols; Polylysine; Proton Magnetic Resonance Spectroscopy; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase; Tumor Necrosis Factor-alpha; Vascular Endothelial Growth Factor A

To evaluate the effects of an intraperitoneal solution of methylene blue (MB), lidocaine and pentoxyphylline (PTX) on intestinal ischemic and reperfusion injury.. Superior mesenteric artery was isolated and clamped in 36 adult male Sprague Dawley rats. After 60 minutes, clamp was removed and a group received intraperitoneally UNITO solution (PTX 25mg/kg + lidocaine 5mg/kg + MB 2mg/kg), while the other group was treated with warm 0.9% NaCl solution. Rats were euthanized 45 min after drug administration. Lung and bowel were collected for histological evaluation (using Park's score) and determination of myeloperoxidase (MPO) and malondialdehyde (MDA) levels.. Control samples showed lymphoplasmocytic infiltrate and crypt necrosis of villi. MPO and MDA measurements shown no differences between treated and control groups.. The combination of lidocaine, methylene blue and pentoxyphylline administered intraperitoneally at the studied dose, did not decreased histological lesion scores and biochemical markers levels in intestinal ischemia/reperfusion injury.

Topics: Animals; Anti-Inflammatory Agents; Drug Combinations; Drug Synergism; Inflammation; Infusions, Parenteral; Intestines; Lidocaine; Lung; Male; Malondialdehyde; Methylene Blue; Models, Animal; Pentoxifylline; Peroxidase; Random Allocation; Rats, Sprague-Dawley; Reperfusion Injury; Statistics, Nonparametric

Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) signaling plays a dominant role in the pathogenesis of liver ischemia-reperfusion (IR) injury. Dexmedetomidine (Dex) protects the liver against IR injury via α₂-adrenoceptor activation, but the contribution of TLR4 signaling remains unknown. The authors aimed to examine whether pretreatment with Dex produces hepatic protection and investigate the influence of Dex on TLR4/NF-κB signaling. Dex was given via intraperitoneal injection 30 min prior to orthotopic autologous liver transplantation (OALT) in rats, and three α₂-adrenoceptor antagonists including atipamezole (a nonselective α₂ receptor blocker), ARC-239 (a specific α2B/C blocker) and BRL-44408 (a specific α2A blocker) were injected intraperitoneally 10 min before Dex administration. Histopathologic evaluation of the liver and the measurement of serum alanine aminotransferase activity, TLR4/NF-κB expression in the liver, and pro-inflammatory factors (serum tumor necrosis factor-α, interleukin-1β and hepatic myeloperoxidase) concentrations were performed 8 h after OALT. Dex ameliorated liver injury after OALT probably by suppressing the TLR4/NF-κB pathway and decreasing inflammatory mediator levels. The protective effects of Dex were reversed by atipamezole and BRL-44408, but not by ARC-239, suggesting that these effects were mediated in part by the α2A subtype. In conclusion, Dex attenuates liver injury partly via the α2A-adrenoceptor subtype, and the mechanism is due to the suppression of the TLR4/NF-κB pathway.

Topics: Adrenergic alpha-2 Receptor Agonists; Adrenergic alpha-2 Receptor Antagonists; Animals; Dexmedetomidine; Interleukin-1beta; Liver; Male; NF-kappa B; Peroxidase; Rats; Rats, Sprague-Dawley; Receptors, Adrenergic, alpha-2; Reperfusion Injury; Toll-Like Receptor 4

To investigate the protective effect of metformin on testicular ischemia/reperfusion (I/R) injury in rats.. Eighteen adult male Wistar rats were randomly divided into three experimental groups (n=6), as follows: Sham, I/R, and Metformin. 1-hour ischemia was induced by the left testicular artery and vein clipping followed by 7 days of reperfusion. Metformin (100 mg/kg) was administrated orally for 7 days via oral gavage after ischemic period. At the end of trial, the left testis was removed for histological analysis and oxidative stress measurement.. I/R reduced superoxide dismutase (SOD) activities and testicular Johnsen's scores accompanied by an elevation in malondialdehyde (MDA) and myeloperoxidase (MPO) levels in comparison with the sham group (P < 0.05). Compared to I/R group, metformin restored testicular Johnsen's scores, SOD activity, MDA and MPO levels (P < 0.05).. Metformin has a protective effect against I/R injury on the testis.

Topics: Animals; Male; Malondialdehyde; Metformin; Models, Animal; Oxidative Stress; Peroxidase; Protective Agents; Random Allocation; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase; Testis

To evaluate the effect of Otostegia persica (O. persica) extract on renal damage induced by ischemia/reperfusion (I/R) in diabetic rats.. Forty-eight rats were subjected to right nephrectomy; then, they were allocated into six groups: Sham; Diabetic sham; I/R; Diabetic I/R; I/R+O. persica; Diabetic I/R+O. persica. Diabetes was induced by streptozotocin (200 mg/kg, i.p.). O. persica (300 mg/kg/day, p.o) was administered for 2 weeks. On the 15th day, ischemia was induced in left kidney for 60 min, followed by reperfusion for 24h. Renal functional and biochemical markers were estimated.. I/R in both normal and diabetic rats, induced a significant elevation in serum levels of urea and creatinine (p<0.05). Renal I/R induced a significant increase of malondialdehyde, myeloperoxidase and nitric oxide concentrations associated with significant reduction in superoxide dismutase and catalase activities in comparison with the sham group (p<0.05). Diabetic rats that underwent renal I/R exhibited a significant increase in all the studied parameters with a reduction in the antioxidant enzymes as compared to nondiabetic rats (p<0.05). These deleterious effects associated with renal I/R were improved by the treatment with O. persica (p<0.05).. Otostegia persica pretreatment protected the renal injury from ischemia-reperfusion in diabetic rats.

Topics: Animals; Antioxidants; Blood Glucose; Catalase; Creatinine; Diabetes Mellitus, Experimental; Hypoglycemic Agents; Kidney; Lamiaceae; Lipid Peroxides; Male; Models, Animal; Nephrectomy; Oxidative Stress; Peroxidase; Plant Extracts; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase; Urea

To investigate the effect of Kineret® on ischemia reperfusion (IR) injury in rat ovaries.. Rats were divided into four groups: ovarian IR (IRG); 50 mg/kg Kineret® + ovarian IR (KIR-50); 100 mg/kg Kineret® + ovarian IR (KIR-100); and sham operation (SOC). KIR-50 (n = 10) and KIR-100 (n = 10) groups received an intraperitoneal injection of Kineret® at doses of 50 and 100 mg/kg, respectively. IRG and SOC (n = 10) rat groups were given distilled water as solvent using the same method. The results were compared between the groups.. In rats in which IR occurred, oxidant parameters, such as malondialdehyde (MDA) and myeloperoxidase (MPO), were increased, the level of proinflammatory interleukin 1 beta (IL-1β) was elevated and total glutathione (tGSH) as an antioxidant was decreased in the ovarian tissues. Administration of Kineret® at a dose of 100 mg/kg inhibited the increase of MDA, MOP and IL-1β and a decrease in tGSH caused by IR more significantly than administration of Kineret® at a dose of 50 mg/kg. In addition, 100 mg/kg Kineret® significantly decreased severe hemorrhage, degeneration and inflammatory signs in the follicular cells, caused by IR. Kineret® at 100 mg/kg markedly ameliorated increased apoptosis in ovarian tissue with IR more significantly than 50 mg/kg kineret.. Our findings indicate that Kineret® might be useful in clinical practice for the treatment of damage that may occur as a result of ovarian torsion.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Caspase 3; Disease Models, Animal; Female; Gene Expression; Glutathione; Interleukin 1 Receptor Antagonist Protein; Interleukin-1beta; Malondialdehyde; Ovary; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

The widespread application of tourniquets has reduced battlefield mortality related to extremity exsanguinations. Tourniquet-induced ischemia-reperfusion injury (I/R) can contribute to muscle loss. Postischemic conditioning (PostC) confers protection against I/R in cardiac muscle and skeletal muscle flaps. The objective of this study was to determine the effect of PostC on extremity muscle viability in an established rat hindlimb tourniquet model.. Rats were randomly assigned to PostC-1, PostC-2, or no conditioning ischemic groups (n = 10 per group). Postischemic conditioning, performed immediately after tourniquet release, consisted of four 15-second cycles (PostC-1) or eight 15-second cycles (PostC-2) of alternating occlusion and perfusion of hindlimbs. Twenty-four hours later, muscles were excised. The primary end points were muscle edema and viability; secondary end points were histologic and markers of oxidative stress.. Ischemia-reperfusion injury decreased viability in all tourniquet limbs, but viability was not improved in either PostC group. Likewise, I/R resulted in substantial muscle edema that was not reduced by PostC. The predominant histologic feature was necrosis, but no significant differences were found among groups. Markers of oxidative stress were increased similarly among groups after I/R, although myeloperoxidase activity was significantly increased only in the no conditioning ischemic group. A protective effect from PostC was not observed in our model suggesting that PostC was not effective in reducing I/R skeletal muscle injury or any benefits of PostC were not sustained for 24 hours when tissues were assessed.. These negative findings are pertinent as the military investigates different strategies to extend the safe time for tourniquet application.

Topics: Animals; Edema; Glutathione; Hindlimb; Ischemia; Ischemic Postconditioning; Lipid Peroxidation; Male; Muscle, Skeletal; Muscular Diseases; Nitric Oxide; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Thiobarbituric Acid Reactive Substances; Tissue Survival; Tourniquets

This study was designed to investigate the possible effect of photobiomodulation (PBM) on renal damage induced by ischemia reperfusion (IR) in diabetic rats. Twenty streptozotocin-induced diabetic rats were randomly distributed into two groups, containing ten rats each: IR group (G1) and IR + PBM group (G2). After the right nephrectomy, the ischemia was produced in the left kidney for 30 min, followed by the reperfusion for 24 h. Then, a 685-nm laser diode with an output power of 15 mW (spot size = 0.28 cm

Topics: Acute Kidney Injury; Animals; Catalase; Diabetes Mellitus, Experimental; Glutathione; Kidney Function Tests; Low-Level Light Therapy; Male; Malondialdehyde; Nitric Oxide; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase

Purposes; FK506 (strong immunosuppressive agent) was investigated experimentally whether to protect the hepatic IRI. Methods; Warm ischemic experiment using pigs and rats were performed and examined whether FK506 is effective. Results; The results obtained are as follows. 1. Warm ischemia allowed time of the pigs without FK506 was 150 minutes, but as for that of FK506 group, the extension of 30 minutes was got in 180 minutes. 2. Biliary excretion rate of BSP after reperfusion were better in the group of 180 minutes ischemia with FK506 than in without FK506 group. 3. Chemiluminescence intensity in the peripheral neutrophils and adhered and infiltrated leukocytes in the liver were suppressed markedly by FK506. 4. The vascular endothelium with the scanning electron microscope was relatively preserved in the FK506 group comparing to the placebo group on 30 minutes after reperfusion. 5. Stress gastric ulcer was controlled and myeloperoxidase activity in the gastric mucosa was suppressed by FK506. Conclusion; Based on the results of theses experiments, it was suggested that FK506 has a protective effect on IRI by suppressing: the impairment of sinusoidal endothelial cells; the activation of KCs; the disturbance of micro-circulation; oxidative stress; inflammation; and the accumulation of leukocytes. J. Med. Invest. 63: 262-269, August, 2016.

Topics: Animals; CD4-Positive T-Lymphocytes; Female; Kupffer Cells; Liver; Male; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Swine; Tacrolimus

Life threatening conditions characterized by renal ischemia/reperfusion (RIR) such as kidney transplantation, partial nephrectomy, renal artery angioplasty, cardiopulmonary bypass and aortic bypass surgery, continue to be among the most frequent causes of acute renal failure. The current study investigated the possible protective effects of tadalafil alone and in combination with diltiazem in experimentally-induced renal ischemia/reperfusion injury in rats. Possible underlying mechanisms were also investigated such as oxidative stress and inflammation. Rats were divided into sham-operated and I/R-operated groups. Anesthetized rats (urethane 1.3g/kg) were subjected to bilateral ischemia for 30min by occlusion of renal pedicles, then reperfused for 6h. Rats in the vehicle I/R group showed a significant (p˂0.05) increase in kidney malondialdehyde (MDA) content; myeloperoxidase (MPO) activity; TNF-α and IL-1β contents. In addition significant (p˂0.05) increase in intercellular adhesion molecule-1(ICAM-1) content, BUN and creatinine levels, along with significant decrease in kidney superoxide dismutase (SOD) activity. In addition, marked diffuse histopathological damage and severe cytoplasmic staining of caspase-3 were detected. Pretreatment with combination of tadalafil (5mg/kg bdwt) and diltiazem (5mg/kg bdwt) resulted in reversal of the increased biochemical parameters investigated. Also, histopathological examination revealed partial return to normal cellular architecture. In conclusion, pretreatment with tadalafil and diltiazem combination protected against RIR injury.

Topics: Acute Kidney Injury; Animals; Apoptosis; Blood Urea Nitrogen; Creatinine; Diltiazem; Drug Therapy, Combination; Intercellular Adhesion Molecule-1; Interleukin-1beta; Kidney; Male; Malondialdehyde; Peroxidase; Rats; Reperfusion Injury; Superoxide Dismutase; Tadalafil; Tumor Necrosis Factor-alpha

Limb remote ischemic postconditioning (LRIP) has been confirmed to reduce the ischemia-reperfusion injury but its mechanisms are still not clear. This study clarified the mechanism of LRIP based on the nicotinamide-adenine dinucleotide phosphate (NADPH) oxidase and Myeloid differentiation factor 88 (MyD88)-Tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6)-P38 pathway of neutrophils. Rat middle cerebral artery occlusion (MCAO) model was used in this study. Ischemia-reperfusion injury was carried out by MCAO 1.5 h followed by 24 h reperfusion. LRIP operation was performed to the left femoral artery at 0, 1 or 3 h after reperfusion. Behavioral testing, including postural reflex test, vibrissae-elicited forelimb placing test and tail hang test, showed that LRIP operated at 0 h of reperfusion could significantly ameliorate these behavioral scores. Pathological examinations, infarct size, Myeloperoxidase (MPO) activity showed that LRIP operated at 0 h of reperfusion could significantly ameliorate the pathological scores, reduce the infarct size and MPO activity in the brain and increase the MPO activity in the left leg. By using Neutrophil counting, immunofluorescence and real-time PCR techniques, we found that LRIP operated at 0 h of reperfusion could reduce neutrophil counts in the peripheral blood and downregulate the activation of neutrophil in the peripheral blood and rat brain. Western blots revealed that MyD88, TRAF6, p38 mitogen-activated protein kinase (p38-MAPK) in neutrophils and the phosphorylation of p47phox (Ser 304 and Ser 345) in neutrophil could be downregulated by LRIP. Our study suggests that LRIP inhibits the number and activation of neutrophils in the rat brain and peripheral blood linked to down-regulating the activation of NADPH oxidase in neutrophils by MyD88/TRAF6/p38-MAPK pathway.

Topics: Animals; Brain Ischemia; Extremities; Infarction, Middle Cerebral Artery; Ischemic Postconditioning; Male; Myeloid Differentiation Factor 88; NADPH Oxidases; Neutrophils; p38 Mitogen-Activated Protein Kinases; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Signal Transduction; TNF Receptor-Associated Factor 6

Acute pancreatitis (AP) is an inflammatory disorder that can affect adjacent and/or remote organs. Some evidence indicates that the production of reactive oxygen species is able to induce AP. Protein carbonyl (PC) derivatives, which can also be generated through oxidative cleavage mechanisms, have been implicated in several diseases, but there is little or no information on this biomarker in AP. We investigated the association between some inflammatory mediators and PC, with the severity of ischemia-reperfusion AP. Wistar rats (n = 56) were randomly assigned in the following groups : control; sham, 15- or 180-min clamping of splenic artery, with 24 or 72 h of follow-up. The relationships between serum level of PC and thiobarbituric acid reactive species (TBARS) to myeloperoxidase (MPO) activity in tissue homogenates and to cytokines in culture supernatants of pancreatic samples were analyzed. MPO activity was related to the histology scores and increased in all clamping groups. Tumor necrosis factor-alpha (TNF-α), interleukin 1 beta (IL-1β), and interleukin-6 were higher in the 180-min groups. Significant correlations were found between MPO activity and the concentrations of TNF-α and IL-1β. PC levels increased in the 15-min to 24-h group. TBARS levels were not altered substantially. MPO activity and TNF-α and IL-1β concentrations in pancreatic tissue are correlated with AP severity. Serum levels of PC appear to begin to rise early in the course of the ischemia-reperfusion AP and are no longer detected at later stages in the absence of severe pancreatitis. These data suggest that PC can be an efficient tool for the diagnosis of early stages of AP.

Topics: Animals; Biomarkers; Cytokines; Disease Models, Animal; Female; Pancreatitis, Acute Necrotizing; Peroxidase; Protein Carbonylation; Rats, Wistar; Reperfusion Injury

Orexin-A, besides playing an important role in the mechanism of food intake, exhibits a potent gastroprotective action against the formation of acute gastric mucosal injury. The aim of the present study was to determine the effect of administered orexin-A against ischemia-reperfusion (I/R)-induced gastric injury on the expression of heme oxygenase (HO)-1 and HO-2 in gastric tissue.. Wistar rats were subjected to 30 min of ischemia followed by 3 h reperfusion. Orexin-A was infused at a dose of 500 pmol/kg/min during the I/R period. The lesion area was measured by stereomicroscope. The myeloperoxidase activity and 4-hydroxinonenol-malondialdehyde content of gastric mucosa were evaluated spectrophotometrically, and the gastric tumor necrosis factor-α was measured by enzyme linked immune sorbent assay. The expression of HO-1 and HO-2 was determined by Western blotting analysis.. Orexin-A significantly decreased the I/R-induced gastric lesions, myeloperoxidase activity, and 4-hydroxinonenol-malondialdehyde concentration in gastric tissue exposed to I/R. The gastroprotective effect of orexin-A in gastric I/R model was accompanied by the increase in HO-2 expression and the decrease in HO-1 expression.. Orexin-A exerts a protective action on gastric mucosa subjected to I/R, and this effect is associated with the reduction of neutrophil infiltration and lipid peroxidation in gastric tissue in addition to the increase in HO-2 expression due to the administration of orexin-A.

Topics: Animals; Drug Evaluation, Preclinical; Heme Oxygenase (Decyclizing); Heme Oxygenase-1; Intracellular Signaling Peptides and Proteins; Male; Malondialdehyde; Neuropeptides; Neurotransmitter Agents; Orexins; Peroxidase; Random Allocation; Rats, Wistar; Reperfusion Injury; Stomach; Tumor Necrosis Factor-alpha

This study evaluates the inhibitory effect of IPO against ischemia reperfusion (I/R) induced lung injury in rats.. Anesthetized and mechanically ventilated adult Sprague-Dawley rats were randomly assigned to one of the following groups (n=12 each): the sham operated control group, the ischemia-reperfusion (IR) group (30min of left-lung ischemia and 24h of reperfusion), the IPO group (three successive cycles of 30-s reperfusion per 30-s occlusion before restoring full perfusion), and the dexamethasone plus IPO group (rats were injected with dexamethasone (3mg/kg·day(-1)) 10min prior to the experiment and the rest of the procedures were the same as the IPO group). Lung injury was assessed by wet-to-dry lung weight ratio and tissue apoptosis and biochemical changes.. Lung ischemia-reperfusion increased lung MDA production, serum proinflammatory cytokine count, and MPO activity and reduced antioxidant enzyme activities (all p<0.05 I/R versus sham), accompanied with a compensatory increase in caspase-3, bax, Fas, FasL proteins and a decrease in Bcl-2 protein. Plasma levels of TNF-α, IL-6, and IL-1β were increased in the I/R group (all p<0.05 versus sham). IPO attenuated or prevented all the above changes. Treatment with dexamethasone enhanced all the protective effects of postconditioning.. Postconditioning obviously inhibits I/R induced lung injury by its antioxidant, anti-inflammatory and anti-apoptosis activities.

Topics: Animals; Antioxidants; Apoptosis; bcl-2-Associated X Protein; Caspase 3; Dexamethasone; Fas Ligand Protein; fas Receptor; Free Radical Scavengers; Inflammation; Interleukin-1beta; Interleukin-6; Ischemic Postconditioning; Lung; Male; Malondialdehyde; Peroxidase; Rats; Rats, Sprague-Dawley; Rats, Wistar; Reperfusion Injury; Tumor Necrosis Factor-alpha

The objective of our study is to research biochemically and histopathologically the effect of nimesulide on oxidative damage inflicted by ischemia-reperfusion (I/R) on the rat renal tissue. Twenty-four albino Wistar type of male rats were used for the experiment. The animals were divided into groups as: renal ischemia-reperfusion control (RIR), nimesulide+renal ischemia-reperfusion of 50 mg/kg (NRIR-50), nimesulide+renal ischemia-reperfusion of 100 mg/kg (NRIR-100), and sham groups (SG). In NRIR-50 and NRIR-100 groups were given nimesulide, and RIR and SG groups were given distilled water, an hour after anesthesia. Groups, except for the SG group, 1-h-ischemia and then 6-h-reperfusion were performed. In the renal tissue of the RIR group in which the malondialdehyde (MDA), myeloperoxidase (MPO), and 8-hydroxyguanine (8-OHGua) levels were measured, the COX-1 and COX-2 activities were recorded. Nimesulide at 100 mg/kg doses reduced the oxidant parameters more significantly than 50 mg/kg doses; on the other hand, it raised the antioxidant parameters. It has been shown that 100 mg/kg doses of nimesulide prevented the renal I/R damage more significantly than a dose of 50 mg/kg, which shows that nimesulide, in clinics, could be used in the prevention of I/R damage.

Topics: Animals; Antioxidants; Dose-Response Relationship, Drug; Kidney; Kidney Diseases; Male; Malondialdehyde; Oxidative Stress; Peroxidase; Platelet Aggregation Inhibitors; Prostaglandin-Endoperoxide Synthases; Rats; Rats, Wistar; Reperfusion Injury; Sulfonamides; Time Factors; Treatment Outcome

Ischemic preconditioning (IPC) is described as brief ischemia-reperfusion (I/R) cycles to induce tolerance to subsequent in response to longer I/R insults. Various IPC protocols can be performed in four combinations as follows: at early or late phases and on local or distant organs. Although many experimental studies have been performed on IPC, no consensus has been established on which IPC protocol is most effective. The aims of the present study were as follows: (1) to compare the variables of preconditioning in different combinations (in early versus late phases; local versus remote organ implementations) and (2) to determine the most therapeutic IPC protocol(s).. A subtotal hind limb amputation model with clamping an intact femoral pedicle was used for I/R injury. IPC was induced using hind limb tourniquet with 3 × 10 min I/R cycles before longer I/R insult. Forty-nine rats were divided into seven groups (n = 7), sham, IsO (ischemia only), I/R, early ischemic preconditioning (e-IPC), late ischemic preconditioning (l-IPC), early remote ischemic preconditioning (e-RIPC), and l-RIPC (late-remote) groups, respectively. In the sham group, pedicle occlusion was not performed. Six hours ischemia was challenged in the IsO group. Three hours ischemia followed by 3 h reperfusion was performed in the I/R group. The e-IPC group was immediately preconditioned, whereas the l-IPC group was preconditioned 24 h before I/R injury on the same hind limb. In the e-RIPC and l-RIPC groups, the same protocols were performed on the contralateral hind limb. At the end of the experiments, skeletal muscle tissue samples were obtained for biochemical analysis (Malondialdehyde [MDA], catalase, myeloperoxidase [MPO], and nitric oxide end products [NOx]), light microscopy, and caspase-3 immunohistochemistry for determination of apoptosis.. Tissue biochemical markers were improved in nearly all the IPC groups compared with IsO and I/R groups (P < 0.05). Similarly, the histologic damage scores were decreased in all the IPC groups (P < 0.05). The lowest damage score was in the e-RIPC group followed by the l-RIPC, e-IPC, and l-IPC groups, respectively. The apoptosis scores were significantly high in the I/R group compared with the e-RIPC and l-RIPC groups (P < 0.05). Although apoptosis scores of the e-IPC and l-IPC groups were lower than the I/R group, this finding was not statistically significant (P > 0.05).. All IPC protocols were effective in reducing I/R injury. Among these protocols, e-RIPC achieved most protection.

Topics: Animals; Caspase 3; Catalase; Female; Ischemic Preconditioning; Lower Extremity; Malondialdehyde; Muscle, Skeletal; Nitric Oxide; Peroxidase; Random Allocation; Rats, Sprague-Dawley; Reperfusion Injury

Renal ischemia/reperfusion (I/R) injury is highly associated with morbidity and mortality. Oxidative stress, inflammation, and apoptosis play pivotal roles in the development of renal dysfunction following renal I/R. Experimental studies have reported the effectiveness of many antioxidant and anti-inflammatory compounds against renal I/R injury. On the other hand, açaí (Euterpe oleracea Mart. Palmae, Arecaceae) has recently gained considerable appreciation as a natural source of antioxidants. However, the effect of açaí extract has not been studied before on renal I/R. Therefore, the present study was carried out to investigate the possible mechanisms of renal injury attenuation by açaí extract in a rat renal I/R model.. To achieve the aim of the study, rats were administered açaí extract at two dose levels (500 and 1000 mg/kg) for 15 consecutive days before bilateral renal I/R induction. Serum and kidneys were isolated and used for subsequent biochemical analysis.. The present data showed that açai extract significantly and dose-dependently attenuated I/R-induced renal damage. It suppressed the levels of blood urea nitrogen (BUN), serum creatinine, and renal tissue content of kidney injury molecule-1 (KIM-1). In addition, it inhibited serum lactate dehydrogenase (LDH) activity. Moreover, renal contents of malondialdehyde (MDA), myeloperoxidase (MPO), interferon-gamma (IFN-γ), caspase-3, collagen IV, and endothelin-1 were reduced, while renal interleukin-10 (IL-10) content was increased by açaí extract administration to rats before renal I/R induction.. Açaí extract ameliorated bilateral I/R-induced renal injury in rats in a dose-dependent manner.

Topics: Analysis of Variance; Animals; Antioxidants; Blood Urea Nitrogen; Cell Adhesion Molecules; Creatinine; Cytokines; Dose-Response Relationship, Drug; Enzyme-Linked Immunosorbent Assay; Euterpe; Ischemic Preconditioning; Kidney; L-Lactate Dehydrogenase; Male; Malondialdehyde; Peroxidase; Plant Extracts; Rats; Rats, Wistar; Reperfusion Injury

Ischemia reperfusion injury (IRI) is a leading cause of acute kidney injury, which is associated with high morbidity. The aims of the present study were to examine whether mangiferin attenuates renal IRI in an animal model and to identify the underlying mechanism(s).. Male mice were subjected to right renal ischemia for 30min followed by reperfusion for 24h or to a sham operation during which the left kidney was removed. After the 24h reperfusion, all mice were humanely euthanized and kidney tissues collected. Renal damage and apoptosis were investigated by examining hematoxylin and eosin-stained tissues, and by TUNEL assay and immunohistochemistry. Renal function was examined by measuring the concentrations of creatinine, blood urea nitrogen, and potassium (K(+)) in the serum. MPO activity, the levels of NO, TNF-α, IL-1β, and adenosine, and CD73 expression in renal tissue were also examined.. Mangiferin reduced ischemia reperfusion-induced injury, improved kidney function, and inhibited both proinflammatory responses and tubular apoptosis. In addition, treatment with mangiferin increased adenosine production and CD73 expression in kidney's suffering IRI.. Mangiferin appears to attenuate renal IRI by inhibiting proinflammatory responses and tubular apoptosis and by increasing adenosine production. These effects are associated with the adenosine-CD73 signaling pathway.

Topics: 5'-Nucleotidase; Adenosine; Animals; Apoptosis; Blood Urea Nitrogen; Creatinine; Disease Models, Animal; Gene Expression Regulation; Humans; Interleukin-1beta; Kidney; Male; Mice; Mice, Inbred C57BL; Nitric Oxide; Peroxidase; Potassium; Reperfusion Injury; Signal Transduction; Tumor Necrosis Factor-alpha

Successful drug treatment for ischemia--reperfusion-induced lung injury remains a major clinical problem. Melatonin (MT) is a hormone that is principally synthesized in the pineal gland. It has been shown to exhibit a variety of functions including anti-inflammatory and antioxidant effects. Previous reports on N-myc downstream-regulated gene (NDRG)2 have suggested that it is involved in cellular differentiation, development, antiapoptosis, anti-inflammatory cytokine, and antioxidant. The objective of this study was to test whether MT, a novel NDRG2 activator, can protect against intestinal ischemia-reperfusion-induced lung injury (IIRI).. IIRI was induced in rats by occlusion of the superior mesenteric artery for 60 min, and the occlusion was then released for reperfusion. Rats were randomly divided into six groups as follows: control group; MT group; IIRI group; IIRI+5 mg/kg MT group; IIRI+15 mg/kg MT group; and IIRI+25 mg/kg MT group. The effects of MT on intestinal ischemia-reperfusion-induced lung pathologic changes, inflammatory cytokines release, myeloperoxidase and superoxide dismutase activities, and malondialdehyde level were examined. In addition, the NDRG2 activation in lung tissues was detected by Western blot analysis.. MT pretreatment attenuated edema and the pathologic changes in the lung. MT also decreased the levels of tumor necrosis factor-α, interleukin-1β, and interleukin-8 in bronchoalveolar lavage fluid. In addition, MT markedly prevented IIRI-induced elevation of malondialdehyde and myeloperoxidase levels, as well as reduction of superoxide dismutase activity. Furthermore, the expression of NDRG2 was activated by MT pretreatment in lung tissues.. The present study demonstrates that MT exerted protection against IIRI-induced oxidative stress. The potential mechanism of this action may attribute partly to the activation of NDRG2 expression.

Topics: Animals; Cytokines; Intestines; Lung; Lung Injury; Male; Malondialdehyde; Melatonin; Nerve Tissue Proteins; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Up-Regulation

Although 17β-estradiol (E2) treatment following hemorrhagic shock or ischemic reperfusion prevents organs from dysfunction and injury, the precise mechanism remains unknown. We hypothesize that the E2-mediated attenuation of liver injury following hemorrhagic shock and fluid resuscitation occurs via the p38 mitogen-activated protein kinase (MAPK)-dependent heme oxygenase (HO)-1 pathway. After a 5-cm midline laparotomy, male rats underwent hemorrhagic shock (mean blood pressure ∼40 mmHg for 90 min) followed by fluid resuscitation. At the onset of resuscitation, rats were treated with vehicle, E2 (1 mg/kg) alone, or E2 plus p38 MAPK inhibitor SB-203580 (2 mg/kg), HO-1 inhibitor chromium mesoporphyrin-IX chloride (2.5 mg/kg) or estrogen receptor antagonist ICI 182,780 (3 mg/kg). At 2 h after hemorrhagic shock and fluid resuscitation, the liver injury markers were significantly increased compared with sham-operated control. Hemorrhagic shock resulted in a significant decrease in p38 MAPK phosphorylation compared with the shams. Administration of E2 following hemorrhagic shock normalized liver p38 MAPK phosphorylation, further increased HO-1 expression, and reduced cleaved caspase-3 levels. Coadministration of SB-203580 abolished the E2-mediated attenuation of the shock-induced liver injury markers. In addition, administration of chromium mesoporphyrin-IX chloride or ICI 182,780 abolished E2-mediated increases in liver HO-1 expression or p38 MAPK activation following hemorrhagic shock. Our results collectively suggest that the salutary effects of E2 on hepatic injury following hemorrhagic shock and resuscitation are in part mediated through an estrogen-receptor-related p38 MAPK-dependent HO-1 upregulation.

Topics: Animals; Caspase 3; Chemokine CXCL1; Chemokine CXCL2; Estradiol; Estrogens; Heme Oxygenase-1; Interleukin-6; Liver; Liver Diseases; Male; p38 Mitogen-Activated Protein Kinases; Peroxidase; Rats, Sprague-Dawley; Reperfusion Injury; Shock, Hemorrhagic; Tumor Necrosis Factor-alpha

Intestinal ischemia and reperfusion (I/R) is encountered in various clinical conditions and contributes to multiorgan failure and mortality as high as 60% to 80%. Intestinal I/R not only injures the intestine, but affects remote organs such as the lung leading to acute lung injury. The development of novel and effective therapies for intestinal I/R are critical for the improvement of patient outcome. AICAR (5-aminoimidazole-4-carboxyamide ribonucleoside) is a cell-permeable compound that has been shown to possess antiinflammatory effects. The objective is to determine that treatment with AICAR attenuates intestinal I/R injury and subsequent acute lung injury (ALI). Male Sprague Dawley rats (275 to 325 g) underwent intestinal I/R injury with blockage of the superior mesenteric artery for 90 min and subsequent reperfusion. At the initiation of reperfusion, vehicle or AICAR (30 mg/kg BW) was given intravenously (IV) for 30 min. At 4 h after reperfusion, blood and tissues were collected for further analyses. Treatment with AICAR significantly decreased the gut damage score and the water content, indicating improvement in histological integrity. The treatment also attenuated tissue injury and proinflammatory cytokines, and reduced bacterial translocation to the gut. AICAR administration after intestinal I/R maintained lung integrity, attenuated neutrophil chemotaxis and infiltration to the lungs and decreased lung levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6. Inflammatory mediators, lung-inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins, were decreased in the lungs and lung apoptosis was significantly reduced after AICAR treatment. These data indicate that AICAR could be developed as an effective and novel therapeutic for intestinal I/R and subsequent ALI.

Topics: Acute Lung Injury; Alanine Transaminase; Aminoimidazole Carboxamide; Animals; Anti-Inflammatory Agents; Aspartate Aminotransferases; Bacterial Load; Interleukin-6; Intestinal Mucosa; Intestines; L-Lactate Dehydrogenase; Lung; Lymph Nodes; Male; Mice; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Ribonucleotides; Tumor Necrosis Factor-alpha

Liver ischemia-reperfusion injury (IRI) is a major cause of morbidity and mortality after resection surgery, liver transplantation, and hemorrhagic and septic shock. Mir-155 is upregulated by a broad range of inflammatory mediators, and it has been demonstrated to be involved in both innate and adaptive immune responses. However, the role of mir-155 in liver IRI has never been investigated. In this study, mir-155 deficiency protected mice from liver IRI, as shown by lower serum alanine aminotransferase (ALT) levels and Suzuki scores. Mir-155 deficiency results in the development of M2 macrophages, which respond to IR-induced innate immune stimulation by producing a regulatory inflammatory response with higher level of IL-10, but lower levels of TNF-α, IL-6, and IL-12p40. Mir-155 deficiency suppresses IL-17 expression, which contributes to the liver IRI development. In our further in vitro study, the results show that the Th17 differentiation is inhibited by SOCS1 overexpression and the promoted M2 macrophage development induced by mir-155 deficiency is abolished by SOCS1 knockdown. In conclusion, mir-155 deficiency attenuates liver IRI through upregulation of SOCS1, and this was associated with promoted M2 macrophage and inhibited Th17 differentiation.

Topics: Adaptive Immunity; Alanine Transaminase; Animals; CD4-Positive T-Lymphocytes; Cell Differentiation; Cell Separation; Disease Models, Animal; Flow Cytometry; Immunity, Innate; Inflammation; Interleukin-10; Interleukin-12 Subunit p40; Interleukin-6; Kupffer Cells; Liver; Liver Transplantation; Macrophages; Male; Mice; Mice, Inbred C57BL; MicroRNAs; Peroxidase; Reperfusion Injury; Suppressor of Cytokine Signaling 1 Protein; Suppressor of Cytokine Signaling Proteins; Th17 Cells; Tumor Necrosis Factor-alpha; Up-Regulation

Toll-like receptor-4 has been implicated in modulating ischemia-reperfusion injury in cardiac, hepatic, renal, and cerebral models. However, its role in lung ischemia-reperfusion injury is unknown. We hypothesize that toll-like receptor-4 has a key role in initiating the inflammatory cascade in lung ischemia-reperfusion injury.. We used toll-like receptor-4 specific short interference RNA to achieve toll-like receptor-4 knockdown in rats prior to undergoing ischemia and reperfusion. Lungs were explanted and studied for protein expression and markers of lung injury. Additional animals were evaluated for cellular uptake of toll-like receptor-4 short interference RNA. Toll-like receptor-4 short interference RNA localized to the alveolar macrophage.. In animals pretreated with toll-like receptor-4 short interference RNA, toll-like receptor-4 expression and mitogen-activated protein kinase phosphorylation were suppressed. Markers of lung injury including permeability index, myeloperoxidase content, and bronchoalveolar lavage inflammatory cell counts were all reduced with toll-like receptor-4 knockdown.. Toll-like receptor-4 is critical in the development of lung ischemia-reperfusion injury and its activation in the alveolar macrophage may be the initiating step.

Topics: Animals; Biomarkers; Bronchoalveolar Lavage Fluid; Disease Models, Animal; Lung; Male; Peroxidase; Random Allocation; Rats; Reference Values; Reperfusion Injury; Risk Assessment; RNA, Small Interfering; Sensitivity and Specificity; Toll-Like Receptor 4

Remote ischemic conditioning (RIC) is a known manual conditioning to decrease ischemic reperfusion injury (IRI) but not increase ischemic time. Here we tried to establish a rat RIC model of liver transplantation (LT), optimize the applicable protocols and investigate the protective mechanism.. The RIC model was developed by a standard tourniquet. Sprague-Dawley rats were assigned randomly to the sham operated control (N), standard rat liver transplantation (OLT) and RIC groups. According to the different protocols, RIC group was divided into 3 subgroups (10 min×3, n = 6; 5 min×3, n = 6; 1 min×3, n = 6) respectively. Serum transaminases (ALT, AST), creatine kinase (CK), histopathologic changes, malondialdehyde (MDA), myeloperoxidase (MPO) and expressions of p-Akt were evaluated.. Compared with the OLT group, the grafts subjected to RIC 5min*3 algorithm showed significant reduction of morphological damage and improved the graft function. Also, production of reactive oxygen species (MDA) and neutrophil accumulation (MPO) were markedly depressed and p-Akt was upregulated.. In conclusion, we successfully established a novel model of RIC in rat LT, the optimal RIC 5min*3 algorithm seemed to be more efficient to alleviate IRI of the liver graft in both functional and morphological categories, which due to its antioxidative, anti-inflammation activities and activating PI3K Akt pathway.

Topics: Algorithms; Animals; Extremities; Gene Expression Regulation, Enzymologic; Ischemic Preconditioning; Liver; Liver Transplantation; Male; Malondialdehyde; Models, Animal; Peroxidase; Phosphatidylinositol 3-Kinases; Phosphoproteins; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Up-Regulation

Thioredoxin (TRX) is a 12 kDa protein that is induced by oxidative stress, scavenges reactive oxygen species (ROS) and modulates chemotaxis. Furthermore it is thought to play a protective role in renal ischemia/reperfusion injury. Complement 5a (C5a) is a chemotactic factor of neutrophils and is produced after ischemia/reperfusion injury in the kidney. Both TRX and C5a increase after endurance exercise. Therefore, it may be possible that TRX has an association with C5a in renal disorders and/or renal protection caused by endurance exercise. Accordingly, the aim of this study was to investigate relationships among the changes of urine levels of TRX, C5a and acute kidney injury (AKI) caused by ischemia/reperfusion, inflammatory responses, and oxidative stress following intensive endurance exercise. Also, we applied a newly-developed measurement system of neutrophil migratory activity and ROS-production by use of ex vivo hydrogel methodology with an extracellular matrix to investigate the mechanisms of muscle damage. Fourteen male triathletes participated in a duathlon race consisting of 5 km of running, 40 km of cycling and 5 km of running were recruited to the study. Venous blood and urine samples were collected before, immediately following, 1.5 h and 3 h after the race. Plasma, serum and urine were analyzed using enzyme-linked immunosorbent assays, a free radical analytical system, and the ex vivo neutrophil functional measurement system. These data were analyzed by assigning participants to damaged and minor-damage groups by the presence and absence of renal tubular epithelial cells in the urinary sediments. We found strong associations among urinary TRX, C5a, interleukin (IL)-2, IL-4, IL-8, IL-10, interferon (IFN)-γ and monocyte chemotactic protein (MCP)-1. From the data it might be inferred that urinary TRX, MCP-1 and β-N-acetyl-D-glucosaminidase (NAG) were associated with renal tubular injury. Furthermore, TRX may be influenced by levels of IL-10, regulate chemotactic activity of C5a and IL-8, and control inflammatory progress by C5a and IL-8. In the longer duration group (minor-damage group), circulating neutrophil count, plasma concentration of myeloperoxidase (MPO) and serum concentration of myoglobin were markedly increased. In the higher intensity group (damaged group), neutrophil activation and degranulation of MPO might be inhibited, because not only was ROS production observed to be higher, but also antioxidant capacity and antiinflammatory c

Topics: Acute Kidney Injury; Adult; Athletes; Bicycling; Biomarkers; Cytokines; Exercise; Exercise Therapy; Humans; Inflammation; Kidney Failure, Chronic; Male; Muscle, Skeletal; Neutrophils; Oxidative Stress; Peroxidase; Physical Endurance; Reperfusion Injury; Running; Thioredoxins; Young Adult

Liver ischemia reperfusion (IR) injury triggers a systemic inflammatory response and is the main cause of organ dysfunction and adverse postoperative outcomes after liver surgery. Pentoxifylline (PTX) and hypertonic saline solution (HTS) have been identified to have beneficial effects against IR injury. This study aimed to investigate if the addition of PTX to HTS is superior to HTS alone for the prevention of liver IR injury.. Male Wistar rats were allocated into three groups. Control rats underwent 60 minutes of partial liver ischemia, HTS rats were treated with 0.4 mL/kg of intravenous 7.5% NaCl 15 minutes before reperfusion, and HPTX group were treated with 7.5% NaCl plus 25 mg/kg of PTX 15 minutes before reperfusion. Samples were collected after reperfusion for determination of ALT, AST, TNF-alpha, IL-6, IL-10, mitochondrial respiration, lipid peroxidation, pulmonary permeability and myeloperoxidase.. HPTX significantly decreased TNF-alpha 30 minutes after reperfusion. HPTX and HTS significantly decreased ALT, AST, IL-6, mitochondrial dysfunction and pulmonary myeloperoxidase 4 hours after reperfusion. Compared with HTS only, HPTX significantly decreased hepatic oxidative stress 4 hours after reperfusion and pulmonary permeability 4 and 12 hours after reperfusion.. This study showed that PTX added the beneficial effects of HTS on liver IR injury through decreases of hepatic oxidative stress and pulmonary permeability.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Capillary Permeability; Disease Models, Animal; Drug Synergism; Evans Blue; Free Radical Scavengers; Interleukin-1; Interleukin-10; Ischemia; Lipid Peroxidation; Liver Diseases; Lung; Male; Oxidative Stress; Pentoxifylline; Permeability; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Saline Solution, Hypertonic; Tumor Necrosis Factor-alpha

Temporal expression of chemokines is a crucial factor in the regulation of renal ischemia/reperfusion (I/R) injury and repair. Beside their role in the migration and activation of inflammatory cells to sites of injury, chemokines are also involved in other processes such as angiogenesis, development and migration of stem cells. In the present study we investigated the role of the chemokine MCP-1 (monocyte chemoattractant protein-1 or CCL2), the main chemoattractant for monocytes, during renal I/R injury. MCP-1 expression peaks several days after inducing renal I/R injury coinciding with macrophage accumulation. However, MCP-1 deficient mice had a significant decreased survival and increased renal damage within the first two days, i.e. the acute inflammatory response, after renal I/R injury with no evidence of altered macrophage accumulation. Kidneys and primary tubular epithelial cells from MCP-1 deficient mice showed increased apoptosis after ischemia. Taken together, MCP-1 protects the kidney during the acute inflammatory response following renal I/R injury.

Topics: Animals; Apoptosis; Chemokine CCL2; Cytokines; Disease Models, Animal; Gene Expression; Genes, Lethal; Kidney Tubules; Leukocytes; Macrophages; Male; Mice; Mice, Knockout; Peroxidase; Reperfusion Injury; RNA, Messenger; Time Factors; Up-Regulation

Hepatic injury induced by ischemia-reperfusion (I/R) after transplantation or lobectomy is a major clinical problem. The potential benefit of remifentanil in these hepatic surgeries remains unknown. The current study investigated whether remifentanil protects the liver against I/R injury in a rat model and whether the underlying mechanism involves the modulation of interleukin (IL)-18 signaling.. Male Sprague-Dawley rats were subjected to 45 minutes of partial hepatic ischemia followed by 6 hours of reperfusion. Then, they received an intravenous saline or remifentanil (0.4, 2, or 10 μg/kg per minute) infusion from 30 minutes before ischemia until the end of ischemia with or without previous administration of naloxone, a nonselective opioid receptor antagonist. Serum aminotransferase, hepatic morphology, and hepatic neutrophil infiltration were analyzed. The expression of hepatic IL-18; IL-18-binding protein (BP); and key cytokines downstream of IL-18 signaling were measured.. Remifentanil significantly decreased serum aminotransferase levels and profoundly attenuated the liver histologic damages. Liver I/R injury increased the expression of both hepatic IL-18 and IL-18BP. Although remifentanil pretreatment significantly decreased I/R-induced IL-18 expression, it further upregulated IL-18BP levels in liver tissues. The I/R-induced increases of hepatic interferon-γ, tumor necrosis factor-α and IL-1β expression, and neutrophil infiltration were also significantly reduced by remifentanil. Naloxone inhibited the remifentanil-induced downregulation of IL-18, but not the elevation of IL-18BP, and significantly attenuated its protective effects on liver I/R injury.. Remifentanil protects the liver against I/R injury. Modulating the hepatic IL-18/IL-18BP balance and inhibiting IL-18 signaling mediate, at least in part, the hepatoprotective effects of remifentanil.

Topics: Analgesics, Opioid; Animals; Gene Expression Regulation; Immunohistochemistry; Intercellular Signaling Peptides and Proteins; Interferon-gamma; Interleukin-18; Ischemia; Liver; Male; Naloxone; Neutrophils; Peroxidase; Piperidines; Rats; Rats, Sprague-Dawley; Remifentanil; Reperfusion Injury; Signal Transduction; Transaminases

Intestinal ischemia and reperfusion (IR) syndrome is a life-threatening dilemma caused by diverse events. Higenamine (HG), an active ingredient of Aconiti Lateralis Radix Praeparata, has been traditionally used as a heart stimulant and anti-inflammatory agent in oriental countries. But the function of HG on intestine IR injury has never been investigated.. Mice underwent a 2 cm midline laparotomy, and the superior mesenteric artery (SMA) was obstructed by micro-vascular clamp to induce intestinal ischemia.. In our current study, HG increases mouse intestinal epithelial (IEC-6) cell viability through induced heme oxygenase-1 (HO-1) production in vitro. In our in vivo murine intestinal IR injury model, the increased HO-1 protein level and activity, decreased intestinal injury score, Myeloperoxidase (MPO) activity, and inflammatory cytokine expression induced by HG were all abolished with additional treatment of HO-1 inhibitor zinc protoporphyrin IX (ZnPPIX). Furthermore, HG reduced high mobility group box-1 (Hmgb1) expression in IR injury-performed intestine which was inhibited by additional administration of ZnPPIX. And HG treatment significantly decreased HO-1 expression in nuclear factor erythroid 2-related factor (Nrf-2) SiRNA-transfected cells but not in control SiRNA-transfected cells.. Our study provides evidence HG regulates Nrf2-HO-1-Hmgb1 axis and attenuates intestinal IR injury in mice.

Topics: Alkaloids; Animals; Anti-Inflammatory Agents, Non-Steroidal; Epithelial Cells; Heme Oxygenase-1; HMGB1 Protein; Intestinal Diseases; Laparotomy; Male; Mesenteric Artery, Superior; Mice; Mice, Inbred C57BL; NF-E2-Related Factor 2; Peroxidase; Protoporphyrins; Reperfusion Injury; RNA, Small Interfering; Tetrahydroisoquinolines; Transfection

Glutaraldehyde-polymerized porcine hemoglobin (pPolyHb) is a hemoglobin-based oxygen carrier currently being developed as a potential red blood cell substitute. We assessed the protective effect of pPolyHb on transient focal cerebral ischemia/reperfusion (I/R) injury. Several outcomes were tested, including infarct size, neurological score, production of inflammatory factors, and markers of oxidative status. Our results show that pPolyHb can not only significantly reduce infarct volume and improve neurological score, but can also inhibit the expression of TNF-α and IL-1β. Furthermore, the generation of MDA and MPO was reduced by pPolyHb. We conclude that pPolyHb has a positive effect on transient focal cerebral I/R injury.

Topics: Animals; Blood Substitutes; Brain Diseases; Hemoglobins; Interleukin-1beta; Male; Malondialdehyde; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Swine; Tumor Necrosis Factor-alpha

Allicin, a molecule predominantly responsible for the pungent odor and the antibiotic function of garlic, exhibits various pharmacological activities and has been suggested to be beneficial in the treatment of various disorders. The present study aimed to elucidate the effect of allicin in cerebral ischemia/reperfusion (I/R) injury in rats. Rats were subjected to 1.5 h of transient middle cerebral artery occlusion (MCAO), followed by 24 h of reperfusion. Rats were randomly assigned to the sham surgery group, the MCAO group and the MCAO + allicin group. Neurological score, cerebral infarct size, brain water content, neuronal apoptosis, serum tumor necrosis factor (TNF)‑α and myeloperoxidase (MPO) activity were measured. The results suggested that allicin reduced cerebral infarction area, brain water content, neuronal apoptosis, TNF‑α levels and MPO activity in the serum. The results of the present study indicated that allicin protects the brain from cerebral I/R injury, which may be ascribed to its anti‑apoptotic and anti‑inflammatory effects.

Topics: Animals; Anti-Infective Agents; Anti-Inflammatory Agents; Apoptosis; Brain; Brain Edema; Disease Models, Animal; Disulfides; Garlic; Infarction, Middle Cerebral Artery; Male; Neuroprotective Agents; Peroxidase; Rats, Sprague-Dawley; Reperfusion Injury; Sulfinic Acids; Tumor Necrosis Factor-alpha

Intestinal ischemia-reperfusion (I/R) injury can occur in clinical settings such as organ transplantation, cardiopulmonary bypass and trauma. The noble gas helium attenuates I/R injury in a number of animal organs and thus may offer a strategy for reducing I/R-induced intestinal injury in clinical settings. In the present study, we used four different helium preconditioning (HPC) profiles to investigate the potential beneficial effect of HPC on I/R-induced intestinal injury. Male Sprague-Dawley rats were pretreated with three cycles of air breathing for 5 min combined with three cycles of breathing a 70% helium:30% oxygen mixture for either 2, 5, 10, or 15 min, after which they were subjected to 60-min intestinal ischemia and 60-min reperfusion. Sixty minutes after reperfusion, the intestinal tissues of the variously treated rats were analyzed using histology, immunohistochemistry, terminal dUTP nick-end labeling staining, myeloperoxidase activity assay, Western blotting, and enzyme-linked immunosorbent assay for tumor necrosis factor α and macrophage inflammatory protein 1α. Intestinal permeability was assayed by measuring fluorescein isothiocyanate-dextran release in blood samples. The results showed that the HPC profile consisting of three cycles of 10 or 15 min of helium breathing and three cycles of 5 min of air breathing reduced I/R-induced intestinal injury, cell apoptosis, and the inflammatory response. However, the 2- or 5-min helium breathing did not confer any protective effects. It seems that longer helium episodes should be used in HPC profiles designed to attenuate intestinal I/R injury.

Topics: Animals; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Apoptosis; Chemokine CCL3; Dose-Response Relationship, Drug; Helium; Intestinal Mucosa; Intestines; Ischemic Preconditioning; Male; Permeability; Peroxidase; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

Flavonoids have been subjected to considerable investigation because of its antioxidant and anti-inflammatory properties. However, there is no previously reported study about its effect on hepatic ischemia/reperfusion (I/R). We investigated the effects of micronized purified flavonoid fraction (MPFF) on hepatic I/R injury in rats.. Thirty rats were recruited in the study as follows: group A, sham operation (n = 10); group B, I/R (n = 10); and group C, I/R+MPFF (n = 10). In group C, rats received (80 mg/kg/day) MPFF by gavage for 3 days before surgery, 30 minutes before ischemia and just before the reperfusion. Blood samples were taken, and serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) levels were measured to assess liver functions. Liver tissues were taken for histological evaluation and to determine the total antioxidant capacity (TAC), catalase (CAT), total oxidant status (TOS), oxidative stress index (OSI), and myeloperoxidase (MPO).. The present data showed a decrease in AST, ALT, and LDH levels in the MPFF-treated rats when compared with I/R group rats (P < .001 for all). In the MPFF-treated rats, tissue levels of TOS, OSI, and MPO were significantly lower than those in the I/R group (P < .01, P < .001, and P < .05, respectively). Increases in TAC and CAT levels were statistically significant in the MPFF-treated rats compared with the I/R group (P = .01 for both). On the other hand, MPFF attenuated histological alterations that were induced by I/R.. The present study demonstrates that MPFF ameliorates I/R-induced liver damage, probably through antioxidant and anti-inflammatory properties.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Catalase; Disease Models, Animal; Flavonoids; L-Lactate Dehydrogenase; Liver Diseases; Liver Transplantation; Oxidative Stress; Peroxidase; Rats; Reperfusion Injury

Inflammatory responses play an important role in the tissue damage during hepatic ischemia/reperfusion (I/R). Some resolvins have been shown to have protective properties in reducing I/R injury in the heart and kidney. The aim of the study was to investigate the effects of resolvin D1 (RvD1) on hepatic I/R.. Partial warm ischemia was produced in the left and middle hepatic lobes of Sprague-Dawley rats for 60 min, followed by 6h of reperfusion. Rats received either RvD1 (5 μg/kg) or vehicle by intravenous injection prior to ischemia. On the basis of treatment with RvD1, some rats further received the PI3K inhibitor LY294002. Blood and tissue samples from the groups were collected after 6-h reperfusion.. Our results indicate that the RvD1 receptor ALX/FPR2 is present in liver, and that pretreatment with RvD1 prior to I/R insult significantly blunted I/R-induced elevations of alanine aminotransferase (AST) and aspartate aminotransferase (ALT), and significantly improved the histological status of the liver. Moreover, RvD1 significantly inhibited inflammatory cascades, as demonstrated by attenuations of IL-6, TNF-α and myeloperoxidase levels. Reduced apoptosis, and increased phosphorylation of Akt, were observed in the RvD1 group compared with the control I/R group. These effects of RvD1 on hepatic I/R injury were diminished by the PI3K inhibitor.. Administration of RvD1 prior to hepatic I/R attenuates hepatic injury, at least in part through inhibition of inflammatory response and enhancement of phosphorylation of Akt.

Topics: Alanine Transaminase; Animals; Apoptosis; Aspartate Aminotransferases; Docosahexaenoic Acids; Interleukin-6; Liver; Liver Diseases; Male; Peroxidase; Protective Agents; Proto-Oncogene Proteins c-akt; Rats, Sprague-Dawley; Receptors, Lipoxin; Reperfusion Injury; RNA, Messenger; Tumor Necrosis Factor-alpha

To investigate the effect of low-level laser therapy (LLLT 650 nm) on the lung remote organ injury induced by hindlimb ischemia/reperfusion (I/R). The experiments were performed on 50 healthy mature male Wistar rats weighing mean 230 ± 20 g. The rats were randomly allocated into five equal groups as follows: normal group (animals nonmanipulated), sham group (operated with no ischemia), laser group (animals nonmanipulated and irradiated with laser), I/R group, and I/R + LLLT group. Rats were prepared for sterile surgery, and then, right hindlimbs were subjected to I/R induced by the femoral artery occlusion for duration of 120 min, followed by a 60-min reperfusion. The LLLT (K30 handheld probe, AZOR, Technica, Russia, 650 nm, 30 mW, surface area = 1 cm(2), 60 S/cm(2), energy density = 1.8 J/cm(2)) was carried out by irradiating the rats over a unique point on the skin over the right upper bronchus for 5 and 15 min after initiating reperfusion for 3 min. At the end of the trial, rats were euthanized under deep anesthesia and the right lung tissues were removed. Myeloperoxidase (MPO) and superoxide dismutase (SOD) activities and nitric oxide (NO), malondialdehyde (MDA), and glutathione (GSH) levels were measured in the lung tissues. The tissue samples were further examined histopathologically under light microscopy. It was found that I/R elevated MPO activity, MDA, and NO levels accompanied by a reduction in SOD activities and GSH levels (P < 0.05). LLLT restored MDA and NO levels, MPO and SOD activity, GSH levels, and lung injury scores (P < 0.05). In light of these findings, the LLLT has alleviated the lung tissue injuries after skeletal muscle I/R in this experimental model.

Topics: Animals; Glutathione; Hindlimb; Low-Level Light Therapy; Lung; Lung Injury; Male; Malondialdehyde; Muscle, Skeletal; Nitric Oxide; Peroxidase; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase

Direct peritoneal resuscitation (DPR) has previously been shown to alter blood flow in the small bowel mesenteric vessels in models of intestinal ischemia. However, a survival advantage or its effects on local tissue inflammation have not been previously demonstrated. We hypothesized that DPR would increase survival and decrease intestinal tissue inflammation after intestinal ischemia and reperfusion (I/R) injury.. Eight-week-old male C57Bl6J mice were anesthetized and underwent midline laparotomy. I/R and DPR groups were exposed to superior mesenteric artery occlusion for 60 min with a nontraumatic clamp. Immediately after removal of the clamp, 1 mL of phosphate-buffered saline, 1 mL of minimal essential media, or 1 mL of minimal essential media supplemented with fetal bovine serum, penicillin and/or streptomycin, and glutamine were placed into the abdominal cavity of DPR groups. Animals were then closed in two layers and allowed to reperfuse for 6 h (cytokine analysis, n = 6 per group) or 7 d (survival analysis, n = 10 per group). After 6 h of reperfusion, animals were euthanized. Intestines were harvested and homogenized. Extracts were quantified for total protein content (Bradford assay), myeloperoxidase activity, tissue inflammatory cytokine, and growth factor production. P < 0.05 was significant.. I/R caused marked intestinal ischemia, significant mortality, and a significant increase in tissue cytokine and growth factor levels (P < 0.05). Seven-day survival was 30% for I/R without treatment and rose to 60% with DPR therapy using phosphate-buffered saline as the dialysate. DPR using plain MEM or MEM with supplements after ischemia increased 7-d survival to 90% (P < 0.05). DPR also significantly decreased intestinal tissue levels of myeloperoxidase, as well as intestinal tissue levels of multiple growth factors and inflammatory cytokines.. DPR increases survival and decreases intestinal inflammation after intestinal I/R injury. Translational applications are readily achievable and should be considered for patients with intestinal ischemic pathology.

Topics: Animals; Cytokines; Enteritis; Intercellular Signaling Peptides and Proteins; Intestinal Mucosa; Intestines; Male; Mesenteric Artery, Superior; Mice, Inbred C57BL; Peroxidase; Reperfusion Injury; Resuscitation

To characterize high-mobility group protein 1-toll-like receptor 4 (HMGB1-TLR4) and downstream signaling pathways in intestinal ischemia/reperfusion (I/R) injury.. Forty specific-pathogen-free male C57BL/6 mice were randomly divided into five groups (n = 8 per group): sham, control, anti-HMGB1, anti-myeloid differentiation gene 88 (MyD88), and anti-translocating-chain-associating membrane protein (TRIF) antibody groups. Vehicle with the control IgG antibody, anti-HMGB1, anti-MyD88, or anti-TRIF antibodies (all 1 mg/kg, 0.025%) were injected via the caudal vein 30 min prior to ischemia. After anesthetization, the abdominal wall was opened and the superior mesenteric artery was exposed, followed by 60 min mesenteric ischemia and then 60 min reperfusion. For the sham group, the abdominal wall was opened for 120 min without I/R. Levels of serum nuclear factor (NF)-κB p65, interleukin (IL)-6, and tumor necrosis factor (TNF)-α were measured, along with myeloperoxidase activity in the lung and liver. In addition,morphologic changes that occurred in the lung and intestinal tissues were evaluated. Levels of mRNA transcripts encoding HMGB1 and NF-κB were measured by real-time quantitative PCR, and levels of HMGB1 and NF-κB protein were measured by Western blot. Results were analyzed using one-way analysis of variance.. Blocking HMGB1, MyD88, and TRIF expression by injecting anti-HMGB1, anti-MyD88, or anti-TRIF antibodies prior to ischemia reduced the levels of inflammatory cytokines in serum; NF-κB p65: 104.64 ± 11.89, 228.53 ± 24.85, 145.00 ± 33.63, 191.12 ± 13.22, and 183.73 ± 10.81 (P < 0.05); IL-6: 50.02 ± 6.33, 104.91 ± 31.18, 62.28 ± 6.73, 85.90 ± 17.37, and 78.14 ± 7.38 (P < 0.05); TNF-α, 43.79 ± 4.18, 70.81 ± 6.97, 52.76 ± 5.71, 63.19 ± 5.47, and 59.70 ± 4.63 (P < 0.05) for the sham, control, anti-HMGB1, anti-MyD88, and anti-TRIF groups, respectively (all in pg/mL).Antibodies also alleviated tissue injury in the lung and small intestine compared with the control group in the mouse intestinal I/R model. The administration of anti-HMGB1, anti-MyD88, and anti-TRIF antibodies markedly reduced damage caused by I/R, for which anti-HMGB1 antibody had the most obvious effect.. HMGB1 and its downstream signaling pathway play important roles in the mouse intestinal I/R injury, and the effect of the TRIF-dependent pathway is slightly greater.

Topics: Adaptor Proteins, Vesicular Transport; Animals; Disease Models, Animal; Gene Expression Regulation; HMGB1 Protein; Inflammation; Inflammation Mediators; Interleukin-6; Intestine, Small; Liver; Lung; Male; Mesenteric Artery, Superior; Mesenteric Vascular Occlusion; Mice, Inbred C57BL; Myeloid Differentiation Factor 88; Peroxidase; Reperfusion Injury; RNA, Messenger; Signal Transduction; Toll-Like Receptor 4; Transcription Factor RelA; Tumor Necrosis Factor-alpha

In the present study, we investigated the protective role of ischemic postconditioning (IPOST) against intestine ischemia-reperfusion (I/R) injury in rats. Male Sprague-Dawley rats were divided into sham-operation group (S), I/R group (I/R), ischemic preconditioning group (IPC), ischemic postconditioning group (IPOST). After reperfusion, small intestines were resected for histopathologic evaluations. To evaluate DNA fragmentation, resolving agarose gel electrophoresis was performed. To measure cellular apoptotic rates in intestine tissues, we performed TUNEL staining. To examine lipid peroxidation, production of superoxide radicals and tissue neutrophil infiltration, we tested the content of malondialdehyde and activities of superoxidase dismutase and myeloperoxidase in intestine tissues, respectively. Under light microscope, intestinal mucosal impairment in IPOST and IPC groups was found milder than that in I/R group (P < 0.05). The number of apoptosis cells in I/R group was significantly higher than that in IPOST and IPC groups (P < 0.05). The content of malondialdehyde and activity of myeloperoxidase were significantly reduced in IPOST group and IPC group compared with I/R group, but the activity of superoxidase dismutase in IPOST group and IPC group was enhanced compared with I/R group (P < 0.05). These results suggest that IPOST results in protection against intestine I/R injury, which may be related to reduced production of reactive oxygen species, enhanced activities of antioxidant systems and inhibited apoptosis of intestinal mucosal cells.

Topics: Animals; Apoptosis; Biomarkers; Constriction; Disease Models, Animal; DNA Fragmentation; Intestine, Small; Ischemic Postconditioning; Lipid Peroxidation; Male; Malondialdehyde; Mesenteric Artery, Superior; Neutrophil Infiltration; Peroxidase; Rats, Sprague-Dawley; Reperfusion Injury; Splanchnic Circulation; Superoxide Dismutase; Time Factors

To evaluate whether topical renal hypothermia (TRH) at different levels of temperature has protective effects on lung tissue after renal I/R, through an analysis of organ histology and inflammatory markers in lung tissue.. Twenty-eight male Wistar rats were randomly allocated across four groups and subjected to renal ischemia at different levels of topical renal temperature: normothermia (no cooling, 37°C), mild hypothermia (26°C), moderate hypothermia (15°C), and deep hypothermia (4°C). To induce I/R, the vessels supplying the left kidney of each animal were clamped for 40 minutes, followed by reperfusion. After four hours, another procedure was performed to harvest the tissues of interest. TNF-α, IL-1β and myeloperoxidase activity were measured in lung tissue. Histological analysis was performed in hematoxylin and eosin-stained lung specimens.. Induction of renal I/R under deep topical hypothermia resulted in a significant decrease in lung concentrations of TNF-α compared with normothermic I/R (p<0.05). A trend toward significant correlation was found between lung IL-1β concentration and intensity of hypothermia (Spearman r=-0.37; p=0.055). No difference was found in myeloperoxidase activity or histologic injury between groups.. Topical renal hypothermia reduces activation of the inflammatory cascade in the lung parenchyma. However, tissue-protective effects were not observed.

Topics: Animals; Cold Temperature; Enzyme-Linked Immunosorbent Assay; Hypothermia, Induced; Interleukin-1beta; Kidney; Lung; Male; Peroxidase; Random Allocation; Rats, Wistar; Reperfusion Injury; Reproducibility of Results; Time Factors; Tumor Necrosis Factor-alpha

To investigate the neuroprotective effects of glucagon-like peptide 2 (Glp-2), which increases cerebral blood flow, on the hippocampal complex after cerebral ischemia/reperfusion (I/R) injury in rats.. Animals were randomized into 4 groups: sham, I/R + 0.9% NaCl, I/R + pre-Glp-2, and I/R + post-Glp-2. Cerebral ischemia was performed via the occlusion of the bilateral internal carotid artery for 40 min and continued with a reperfusion process. At the end of 6 h of reperfusion, animals were decapitated in all groups and brain tissues were removed. Malondialdehyde (MDA) and natural intracellular antioxidant glutathione (GSH) levels and myeloperoxidase (MPO) activities were measured in the left hippocampal tissue. The right hippocampal tissues of all group members were taken for histopathologic study.. MDA levels and MPO activities increased from Group I to Group II and decreased from Group II to Groups III and IV. On the other hand, GSH levels were not significantly different among the groups. The number of apoptotic hippocampal tissue cells increased from Group I to Group II and decreased from Group II to Groups III and IV.. Our preliminary study revealed that Glp-2 treatment may decrease oxidative damage from I/R in cerebral tissue.

Topics: Animals; Apoptosis; Brain Ischemia; Cell Death; Disease Models, Animal; Glucagon-Like Peptide 2; Glutathione; Hippocampus; Male; Malondialdehyde; Neuroprotective Agents; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase

Ischemia/reperfusion (I/R) injury of skeletal muscles is common pathophysiology during surgeries and the superoxide dismutase (SOD) plays a critical role in this process. SOD-modeled coordination compound (MSODa) may simulate the protective effects as SOD.. Therefore, this study was designed to explore the protective effects and underlying mechanism of MSODa on malondialdehyde (MDA) and integrin-β2 (CD11b/CD18) in plasma, myeloperoxidase (MPO) and intercellular cell adhesion molecule-1 (ICAM-1) in tissue, and morphological changes before and after I/R injury. The rat model of I/R in hind limb was established and randomly divided into sham, ischemia, I/R, I/R-treated with saline, SOD, and MSODa, respectively.. These results showed that averaged values for MDA, MPO, CD11b/CD18, and ICAM-1 were significantly increased (P < 0.01 vs ischemia alone) in a time-dependent fashion along with marked tissue remodeling, such as abnormal arrangement of muscular fibers, interstitial edema, vasodilation with no-reflow, inflammatory cells adherent and infiltration, structural changes in mitochondrial, and decrease in glycogens as well. However, all parameter changes induced by I/R injury were reversed, at least partially, by MSODa and SOD treatments and intriguingly, the beneficial/protective effects of MSODa was superior to SOD with an early onset.. This novel finding demonstrates that MSODa improves I/R injury of skeletal muscles due at least partially to inhibition of adherent molecule expression and reduction of oxygen free radical formation during I/R pathophysiological processes and this protective action of MSODa was superior to SOD, highlighting the bright future for MSODa in clinical management of tissue I/R injury.

Topics: Animals; Biomimetic Materials; CD18 Antigens; Disease Models, Animal; Gene Expression Regulation; Intercellular Adhesion Molecule-1; Male; Malondialdehyde; Muscle, Skeletal; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase

Paraplegia due to ischemia-reperfusion (I/R) injury of the spinal cord is a devastating complication of thoracoabdominal aortic surgery. Cysteinyl leukotrienes are potent mediators of inflammation that are associated with I/R injury. The present study was designed to investigate the role of montelukast, a selective reversible CysLT1 receptor antagonist, on spinal cord I/R injury in an experimental model.. Twenty-one male Sprague-Dawley rats were randomly assigned to three groups (n=7 per group) as G1 (no aortic occlusion and montelukast administration), G2 (45 min. aortic occlusion; no montelukast administration) and G3 (45 min. aortic occlusion, 10 mg/kg montelukast administration). After neurologic evaluation using the Motor Deficit Index (MDI) score at the 48th hour of reperfusion, lumbar spinal cords were removed for histopathological evaluation and immunohistochemical staining for HSP70, interleukin-6 and myeloperoxidase (MPO).. All rats in the G1 group had a normal neurological status and their MDI score was 0 (p < 0.05). The MDI score of G3 was significantly lower than G2 group (2.8 vs. 5.5; p < 0.05). Vacuolar congestion was found to be significantly lower in G1 than the other groups (p=0.0001). The interleukin-6 receptor level was found to be significantly lower in G3 group than the control group (p=0.013). There was no statistically significant difference found among the groups in terms of the degree of HSP70 and MPO staining.. Increased generation of leukotrienes in postischemic organs play an important role in I/R injury. The findings of the current study demonstrated that montelukast improved motor recovery and decreased IL-6 levels in spinal cord I/R injury.

Topics: Acetates; Animals; Cyclopropanes; Interleukin-6; Leukotriene Antagonists; Male; Neuroprotective Agents; Paraplegia; Peroxidase; Quinolines; Rats; Rats, Sprague-Dawley; Receptors, Leukotriene; Reperfusion Injury; Spinal Cord Ischemia; Sulfides

Reperfusion of ischemic limbs can induce inflammation and subsequently cause acute lung injury. Caffeine, a widely used psychostimulant, possesses potent anti-inflammatory capacity. We elucidated whether caffeine can mitigate lung inflammation caused by ischemia-reperfusion (IR) of the lower limbs. Adult male Sprague-Dawley rats were randomly allocated to receive IR, IR plus caffeine (IR + Caf group), sham-operation (Sham), or sham plus caffeine (n = 12 in each group). To induce IR, lower limbs were bilaterally tied by rubber bands high around each thigh for 3 hours followed by reperfusion for 3 hours. Caffeine (50 mg/kg, intraperitoneal injection) was administered immediately after reperfusion. Our histological assay data revealed characteristics of severe lung inflammation in the IR group and mild to moderate characteristic of lung inflammation in the IR + Caf group. Total cells number and protein concentration in bronchoalveolar lavage fluid of the IR group were significantly higher than those of the IR + Caf group (P < 0.001 and P = 0.008, resp.). Similarly, pulmonary concentrations of inflammatory mediators (tumor necrosis factor-α, interleukin-1β, and macrophage inflammatory protein-2) and pulmonary myeloperoxidase activity of the IR group were significantly higher than those of the IR + Caf group (all P < 0.05). These data clearly demonstrate that caffeine could mitigate lung inflammation induced by ischemia-reperfusion of the lower limbs.

Topics: Animals; Caffeine; Lower Extremity; Lung; Male; Oxidative Stress; Peroxidase; Pneumonia; Rats; Rats, Sprague-Dawley; Reperfusion Injury

To investigate the effects of N-acetylcysteine (NAC) and high-dose atorvastatin (ATOR) in reducing oxidative stress in a rat kidney model of ischemia-reperfusion injury.. Forty female rats underwent clamping of the left renal artery for 30 minutes, followed by reperfusion. The effects of pre-ischemic administration of NAC and/or ATOR were evaluated within 4 groups: a) control (no NAC, no ATOR); b) NAC (intraperitoneal NAC administration); c) ATOR (oral ATOR administration); and d) NAC+ATOR (both drugs). Oxidative stress was assessed by measuring the activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and myeloperoxidase (MPO). Post-ischemia-reperfusion injury was evaluated by means of renal histology.. NAC, ATOR, and NAC+ATOR in rats showed lower MPO (P < .05) and higher GPx activity (P < .05) versus control; SOD activity was lower in NAC versus ATOR (P < .05). No difference among groups was found at histology. However, a lower rate of tubular ischemic lesions was evident in NAC+ATOR versus control (P = .07).. Atorvastatin pretreatment provides protection against oxidative stress in a rat kidney model of ischemia-reperfusion injury, reinforcing the evidence of a beneficial effect of statins beyond their cholesterol-lowering properties.

Topics: Acetylcysteine; Animals; Atorvastatin; Catalase; Female; Free Radical Scavengers; Glutathione Peroxidase; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Kidney; Kidney Diseases; Oxidation-Reduction; Oxidative Stress; Peroxidase; Rats; Reperfusion Injury; Superoxide Dismutase

Ischemia-reperfusion (IR) causes various damages in renal tissues, which is exacerbated by hypoxia-induced excessive inflammation and deteriorates the prognosis of patients after kidney surgery. Celastrol is a potent inflammation inhibitor that has little toxicity. In this report, we investigated whether celastrol protects against IR-induced renal injury in rats.. Renal IR injury was induced by occlusion of the bilateral renal pedicles for 45 min followed by reperfusion for 6 h. Celastrol or vehicle solution was intraperitoneally injected 30 min before renal ischemia, respectively. Renal histology, function, and pro-inflammatory cytokines and mediators were assessed. The effect of celastrol on nuclear translocation of nuclear factor kappa B (NF-κB) was also measured.. Celastrol significantly suppressed elevation of the renal function markers and the lipid peroxidation level, alleviated renal tubular damage, and decreased the levels of tumor necrosis factor-α, interleukin-1β, and monocyte chemotactic protein-1 (MCP-1) messenger RNA in kidney caused by IR. Moreover, celastrol prevented IR-induced expression of pro-inflammatory mediators, which was associated with suppression of nuclear translocation of NF-κB subunit p65.. Celastrol ameliorated the acute kidney injury caused by IR, which was associated with inhibiting local NF-κB activation and inflammation. Our findings suggest that celastrol could be useful for preventing IR-induced renal injury.

Topics: Animals; Cyclooxygenase 2; Intercellular Adhesion Molecule-1; Kidney; Male; Nitric Oxide Synthase Type II; Pentacyclic Triterpenes; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Triterpenes

In patients with acute kidney injury (AKI) mortality remains high, despite the fact that the patients are treated with continuous renal replacement therapy. The interaction between the kidney and the immune system might explain the high mortality observed in AKI. In order to elucidate the interaction between the kidney and immune system we developed a two-hit model of AKI and endotoxemia. Our hypothesis was that ischemia/reperfusion (I/R) of the kidney simultaneously with endotoxemia would generate a more extensive inflammatory response compared to I/R of the hind legs. Our expectation was that elevated levels of cytokines would be found in both blood and in organs distant to the kidneys. Forty mice were divided into five groups. The mice were subjected to the following operations: A: Sham only, no lipopolysaccharide (LPS); B: I/R of both kidneys + LPS; C: LPS only; D: Nephrectomy + LPS; E: I/R of both hind legs + LPS. In groups B and E, I/R times were identical. All mice were kept alive for 24 h and then sacrificed. Levels of interleukin (IL)-1β, IL-6, IL-10, and tumor necrosis factor-α were measured in the blood. The activity of myeloperoxidase (MPO) in lungs, kidneys, and liver was evaluated as an indirect measurement of accumulation of granulocytes. In this study, significantly higher amount of IL-6 and IL-10 in the plasma was observed following renal I/R compared to hind leg I/R. The elevated levels of cytokine in plasma were observed following nephrectomy and endotoxemia. The neutrophil infiltration of distant organs measured by the levels of MPO in the lung and liver also showed a significantly higher level in renal I/R compared to hind leg I/R. Renal I/R is associated with a more pronounced inflammatory response in blood and distant organs. The high cytokine levels measured following nephrectomy might be explained by compromised elimination of cytokines by the kidney in AKI.

Topics: Acute Kidney Injury; Animals; Disease Models, Animal; Endotoxemia; Inflammation; Interleukin-10; Interleukin-1beta; Interleukin-6; Ischemia; Kidney; Lipopolysaccharides; Liver; Lung; Male; Mice; Mice, Inbred C57BL; Nephrectomy; Neutrophil Infiltration; Peroxidase; Reperfusion Injury; Tumor Necrosis Factor-alpha

Gamma amino butyric acid (GABA) has been reported to be renoprotective in various preclinical studies. Sodium valproate (SVP) is documented to protect against renal injury through its histone deacetylase-inhibiting activity. The present study investigated the involvement of GABAA receptors and the role of GABAergic activity of SVP against ischemia-reperfusion-induced acute kidney injury (AKI) in rats. The rats were subjected to bilateral renal ischemia for 40 min followed by reperfusion for 24 h to induce AKI. The creatinine clearance, serum urea, uric acid, lactate dehydrogenase, potassium, fractional excretion of sodium, and microproteinuria were measured to assess kidney injury. The thiobarbituric acid-reactive substances, reduced glutathione level, myeloperoxidase, and catalase activity were assayed to assess oxidative stress in renal tissues along with hematoxylin-eosin staining to observe histopathological changes. The ischemia-reperfusion-induced AKI witnessed an increase in serum parameters, microproteinuria, oxidative stress, and histopathological changes in renal tissues. Picrotoxin aggravated ischemia-reperfusion injury-induced AKI confirming the role of GABAA receptors in AKI. The SVP treatment afforded protection against AKI that was blocked by concurrent treatment with picrotoxin. Hence, it is concluded that regulation of GABAA receptors is important for management of AKI. Moreover, the GABAergic activity of SVP is important for its renoprotective effect.

Topics: Acute Kidney Injury; Animals; Catalase; Creatinine; GABA Agents; Glutathione; Kidney; L-Lactate Dehydrogenase; Male; Peroxidase; Picrotoxin; Potassium; Protective Agents; Proteinuria; Rats; Rats, Wistar; Receptors, GABA-A; Reperfusion Injury; Sodium; Superoxides; Thiobarbituric Acid Reactive Substances; Urea; Uric Acid; Valproic Acid

Ischemia-reperfusion (I/R) injury leads to increased mortality and morbidity in lung transplant patients. Lung I/R injury involves inflammation contributed by innate immune responses. IL-17 and TNF-α, from iNKT cells and alveolar macrophages, respectively, contribute importantly to lung I/R injury. This study tests the hypothesis that IL-17 and TNF-α synergistically mediate CXCL1 (a potent neutrophil chemokine) production by alveolar type II epithelial (ATII) cells via an NADPH oxidase-dependent mechanism during lung I/R. Using a hilar clamp model, wild-type and p47(phox-/-) (NADPH oxidase-deficient) mice underwent left lung I/R, with or without recombinant IL-17 and/or TNF-α treatment. Wild-type mice undergoing I/R treated with combined IL-17 and TNF-α had significantly enhanced lung dysfunction, edema, CXCL1 production, and neutrophil infiltration compared with treatment with IL-17 or TNF-α alone. However, p47(phox-/-) mice had significantly less pulmonary dysfunction, CXCL1 production, and lung injury after I/R that was not enhanced by combined IL-17-TNF-α treatment. Moreover, in an acute in vitro hypoxia-reoxygenation model, murine ATII cells showed a multifold synergistic increase in CXCL1 expression after combined IL-17-TNF-α treatment compared with treatment with either cytokine alone, which was significantly attenuated by an NADPH oxidase inhibitor. Conditioned media transfer from hypoxia-reoxygenation-exposed iNKT cells and macrophages, major sources of IL-17 and TNF-α, respectively, to ATII cells significantly enhanced CXCL1 production, which was blocked by NADPH oxidase inhibitor. These results demonstrate that IL-17 and TNF-α synergistically mediate CXCL1 production by ATII cells after I/R, via an NADPH oxidase-dependent mechanism, to induce neutrophil infiltration and lung I/R injury.

Topics: Airway Resistance; Alveolar Epithelial Cells; Animals; Blood Pressure; Cells, Cultured; Chemokine CXCL1; Interleukin-17; Lung; Macrophages, Alveolar; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; NADPH Oxidases; Natural Killer T-Cells; Neutrophil Infiltration; Peroxidase; Pulmonary Artery; Pulmonary Edema; Reperfusion Injury; Superoxides; Tumor Necrosis Factor-alpha

Heme oxygenase-1 (HO-1) has been shown to have antioxidant and anti-apoptotic properties. The present study transduced HO-1 protein into intestinal tissues using PEP-1, a cell-penetrating peptide, and investigated its potentiality in prevention against intestinal ischemia/reperfusion (I/R) injury.. PEP-1-HO-1 fusion protein was administered intravenously to explore the time and dose characteristics through measuring serum HO-1 levels. Twenty-four male Sprague-Dawley rats were randomly divided into three groups: sham, intestinal I/R (II/R), II/R + PEP-1-HO-1 fusion protein (HO). The model was established by occluding the superior mesenteric artery for 45 min followed by 120 min reperfusion. In HO group, PEP-1-HO-1 was administered intravenously 30 min before ischemia, whereas animals in sham and II/R groups received the equal volume of physiological saline. After the experiment, the intestines were harvested for determination of histologic injury, wet/dry ratio, enzyme activity, apoptosis, and His-probe protein (one part of PEP-1-HO-1).. Levels of serum HO-1 were dose- and time-dependent manner after intravenous injection of PEP-1-HO-1. I/R caused deterioration of histologic characteristics and increases in histologic injury scoring, wet/dry ratio, myeloperoxidase activity, malondialdehyde, and intestinal apoptosis. These changes were also accompanied by a decrease in superoxide dismutase activity (P < 0.05). PEP-1-HO-1 treatment significantly reversed these changes (P < 0.05). Furthermore, His-probe protein expression was only detected in PEP-1-HO-1-treated animals.. Treatment of PEP-1-HO-1 attenuates intestinal I/R injury, which might be attributable to its antioxidant and anti-apoptotic roles of HO-1.

Topics: Animals; Apoptosis; Heme Oxygenase-1; Injections, Intravenous; Intestines; Lipid Peroxidation; Male; Malondialdehyde; Organ Size; Peroxidase; Phenols; Plant Extracts; Random Allocation; Rats; Rats, Sprague-Dawley; Recombinant Fusion Proteins; Reperfusion Injury

Intestinal ischemia and reperfusion (I/R) is a clinical problem occurred for diverse causes with high mortality. Prophylaxis and treatment of intestinal I/R remains a challenge for clinicians. The purpose of the present study was to explore the role of Notoginsenoside R1 (R1), a major component form of Panax notoginseng, in management of intestinal I/R injury. Intestinal I/R was induced in male Sprague-Dawley rats by clamping the superior mesenteric artery for 90 min followed by reperfusion for 60 min or 3 days. R1 (10 mg·kg(-1)·h(-1)) was administered either 20 min before ischemia or 20 min after reperfusion. Intestinal microcirculation was evaluated by intravital microscopy over 60 min reperfusion. Sixty minutes or 3 days after reperfusion, rats were killed for histological examination of the jejunum tissue and immunohistochemical localization of myeloperoxidase and CD68. ATP, ADP, and AMP content in jejunum tissue was assessed by ELISA. Activation of nuclear factor-κB (NF-κB) and expression of ATP5D and tight junction proteins were determined by Western blotting. The results demonstrated that R1 is capable of attenuating intestinal I/R-induced microvascular hyperpermeability, inflammatory cytokine production, NF-κB activation, and loss of tight junction proteins, as well as improving energy metabolism during I/R. The results of the present study suggest R1 as an option in protecting against intestinal I/R injury.

Topics: Animals; Apoptosis; Blotting, Western; Capillary Permeability; Energy Metabolism; Ginsenosides; Intestinal Diseases; Intestines; Jejunum; Male; Malondialdehyde; Microcirculation; Neutrophil Infiltration; Peroxidase; Rats; Rats, Sprague-Dawley; Regional Blood Flow; Reperfusion Injury; Tight Junctions

Nuclear factor κB (NF-κB) plays an important role in the regulation of inflammatory proteins. However, it is unclear whether the NF-κB/intercellular adhesion molecule-1 (ICAM-1) pathway is involved in the adhesion of neutrophils and renal injury after hypoxia-ischemia (HI) in neonates. In this report we investigated whether NF-κB and its downstream molecule ICAM-1 were involved in renal injury induced by postasphyxial serum (PS) from neonates. Human renal proximal tubular (HK-2) cells were preincubated with 10 % fetal calf serum (control), 20 % neonatal PS, or 20 % PS plus pyrolidine dithiocarbamate (PDTC). The expression of IκBα, NF-κB p65, and ICAM-1 in HK-2 cells was determined by Western blot and/or immunohistochemistry. Nuclear translocation of NF-κB p65 in HK-2 cells was detected by immunofluorescence and Western blot. The ICAM-1 mRNA was determined by RT-PCR. Then HK-2 cells were cultured with neutrophils from neonates with asphyxia. After HK-2 cells had been cultured with neutrophils, we detected myeloperoxidase (MPO) activity, the leakage rate of lactate dehydrogenase (LDH), and cell viability. We found that PS preincubation resulted in significantly decreased IκBα expression and increased expression of NF-κB and ICAM-1, and facilitated the nuclear translocation of NF-κB in HK-2 cells. PS preincubation increased MPO activity, leading to elevated leakage rates of LDH and decreased cell viability after neutrophil exposure. Furthermore, the inhibition of NF-κB activity by PDTC significantly upregulated IκBα expression, decreased NF-κB and ICAM-1 expression, downregulated the nuclear translocation of NF-κB, and decreased MPO activity. This leads to decreased leakage rates of LDH and increased cell viability after neutrophil exposure. Our findings suggest that NF-κB/ICAM-1 pathway may be involved in neutrophil-endothelial interactions and neonatal renal injury after HI.

Topics: Asphyxia Neonatorum; Cell Adhesion; Cell Hypoxia; Cell Line; Cell Survival; Humans; I-kappa B Proteins; Infant, Newborn; Intercellular Adhesion Molecule-1; Kidney Tubules; L-Lactate Dehydrogenase; Neutrophils; NF-KappaB Inhibitor alpha; Peroxidase; Reperfusion Injury; RNA, Messenger; Transcription Factor RelA

The small G protein RhoA and its downstream effector Rho-kinase play an important role in various physiopathological processes including ischemia/reperfusion (I/R) injury. Reactive oxygen and nitrogen species produced by iNOS and NADPH oxidase are important mediators of inflammation and organ injury following an initial localized I/R event. The aim of this study was to determine whether RhoA/Rho-kinase signaling pathway increases the expression and activity of MEK1, ERK1/2, iNOS, gp91(phox), and p47(phox), and peroxynitrite formation which result in oxidative/nitrosative stress and inflammation leading to hindlimb I/R-induced injury in kidney as a distant organ and gastrocnemius muscle as a target organ. I/R-induced distant and target organ injury was performed by using the rat hindlimb tourniquet model. I/R caused an increase in the expression and/or activity of RhoA, MEK1, ERK1/2, iNOS, gp91(phox), p47(phox), and 3-nitrotyrosine and nitrotyrosine levels in the tissues. Although Rho-kinase activity was increased by I/R in the kidney, its activity was decreased in the muscle. Serum and tissue MDA levels and MPO activity were increased following I/R. I/R also caused an increase in SOD and catalase activities associated with decreased GSH levels in the tissues. Y-27632, a selective Rho-kinase inhibitor, (100µg/kg, i.p.; 1h before reperfusion) prevented the I/R-induced changes except Rho-kinase activity in the muscle. These results suggest that activation of RhoA/Rho-kinase/MEK1/ERK1/2/iNOS pathway associated with oxidative/nitrosative stress and inflammation contributes to hindlimb I/R-induced distant organ injury in rats. It also seems that hindlimb I/R induces target organ injury via upregulation of RhoA/MEK1/ERK1/2/iNOS pathway associated with decreased Rho-kinase activity.

Topics: Amides; Animals; Catalase; Glutathione; Inflammation; Kidney; Male; Malondialdehyde; MAP Kinase Kinase 1; MAP Kinase Signaling System; Muscle, Skeletal; NADPH Oxidases; Nitric Oxide Synthase Type II; Oxidative Stress; Peroxidase; Peroxynitrous Acid; Pyridines; Rats; Rats, Wistar; Reperfusion Injury; rho-Associated Kinases; rhoA GTP-Binding Protein; Superoxide Dismutase; Tyrosine

Geraniol is an acyclic monoterpene alcohol commonly used as a flavoring agent. The present study was undertaken to investigate antiulcerogenic effects of geraniol and to determine the possible mechanisms involved in this action. In the model of the ethanol-induced ulcer, treatment of rats with geraniol by oral route significantly inhibited gastric lesions by 70 % (7.50 mg/kg) to 99 % (200 mg/kg). Analysis of the gastric tissue of rats treated with geraniol (7.50 mg/kg) revealed that total glutathione content levels (GSH) increased and levels of myeloperoxidase (MPO) decreased in the gastric mucosa. Oral treatment with geraniol significantly decreased the number of ulcerative lesions induced by ischemia/reperfusion injury by 71 % and the duodenal ulcers induced by cysteamine by 68 %. The action of geraniol was mediated by the activation of defensive mucosa-protective factors such as the nitric oxide (NO) pathway, endogenous prostaglandins, increased mucus production, increased sulfhydryl compounds, antioxidant properties and the stimulation of calcitonin gene-related peptide (CGRP) release through the activation of transient receptor potential vanilloid (TRPV). The multifaceted gastroprotective mechanisms of geraniol represent a promising option for the treatment of gastric and duodenal mucosa injury.

Topics: Acyclic Monoterpenes; Animals; Anti-Ulcer Agents; Cysteamine; Duodenal Ulcer; Duodenum; Ethanol; Flavoring Agents; Gastric Mucosa; Glutathione; Male; Mucus; Nitric Oxide; Peroxidase; Pylorus; Rats; Rats, Wistar; Reperfusion Injury; Stomach; Stomach Ulcer; Terpenes

Brain-derived neurotrophic factor (BDNF) plays a key role in the pathophysiology process and therapy of spinal cord injury (SCI). Accordingly, zinc regulates the expression of BDNF and its receptor in the central nervous system, the mechanism of which is still unknown. The present study investigates whether supplement zinc could reduce neurological damage in a rat model, with spinal cord ischemia-reperfusion (I/R) injury and how the effect of zinc transporter 1(ZnT-1) was involved.. 100 Sprague-Dawley male rats were randomly and evenly divided into four groups. They were subjected to spinal cord ischemia by clamping the abdominal aorta for 45 min. Rats in the zinc-deficient dietary model group (ZD), zinc-adequate dietary model group (ZA), and zinc-high dietary model group (ZH) were given free access to purified diet, containing 5, 30, or 180 mg Zn/kg. Sham operation rats were subjected to laparotomy without clamping of the aorta and were fed by ZA diet (30 mg Zn/kg). Neurological function was scored by Tarlov's score. The spinal cord segments (L5) were harvested for histological examination, auto-metallographic (AMG) analysis, myeloperoxidase (MPO) activity analysis, expression of ZnT-1 and BDNF.. The rats in the ZH group have shown the higher neurological scores, slighter histological changes and the attenuated MPO activity, compared with those in the ZD and ZA groups at the four observation time points (p<0.05). The AMG staining density in the ZH group was significantly higher than that of ZD group in 14 days later after the operation. Compared with other groups, ZH group's expression of Zn-T1 and BDNF were significantly increased, and was positively correlated with the same time points after surgery (Spearman rho=0.403, p=0.0152.). These findings suggest that zinc supplement can significantly reduce the spinal cord I/R injury in rats. The mechanism may be related with restraining the MPO activity and increasing of ZnT-1, which promoted the synthesis and release of BDNF.

Topics: Animals; Brain-Derived Neurotrophic Factor; Cation Transport Proteins; Dietary Supplements; Male; Movement; Peroxidase; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Spinal Cord Ischemia; Treatment Outcome; Zinc

Hypercholesterolemia (HC) and aging combine to increase the incidence of cerebrovascular disease through oxidative stress. Our investigation examined the effects of diet-induced hypercholesterolemia (2% for 8weeks) on the extent of brain injury in response to global cerebral ischemia/reperfusion (GCI/R) and the neuroprotective potentials of rosiglitazone in relation to oxidative stress. HC exacerbated the decline in the brain levels of GSH and the increase in MPO, proinflammatory markers and hippocampal lesions in response to GCI/R. HC rats receiving rosiglitazone, PPAR-γ agonist, demonstrated preservation of cell viability of CA1 hippocampal region and attenuation of brain edema. They also showed elevated levels of GSH and low levels of the other parameters similar to non-HC rats subjected to GCI/R. In vitro, rosiglitazone dose-dependently inhibited ROS generation by neutrophils. The results suggest exacerbation of brain lesions by HC in response to GCI/R. The neuroprotective therapeutic potentials of rosiglitazone are comparable to non-HC animals. Mechanisms of protection are possibly due to anti-oxidant, anti-inflammatory effects and scavenging properties of rosiglitazone. These results add to the beneficial therapeutic effects of rosiglitazone and its significance for age-associated diseases including hypercholesterolemia.

Topics: Animals; Brain Edema; Brain Ischemia; Dose-Response Relationship, Drug; Glutathione; Hypercholesterolemia; Interleukin-6; Lipid Peroxidation; Male; Neuroprotective Agents; Oxidative Stress; Peroxidase; PPAR gamma; Rats; Rats, Wistar; Reperfusion Injury; Rosiglitazone; Thiazolidinediones; Tumor Necrosis Factor-alpha

It has been well proved that acute inflammatory response and hepatocellular apoptosis contributed to the pathogenesis of liver ischemia reperfusion (IR) injury. A vast amount of research has demonstrated that magnesium lithospermate B (MLB) has potent anti-apoptosis and potential anti-inflammatory pharmacological properties. However, it has not previously been examined whether MLB can attenuate hepatic IR injury. Firstly, the optimal dose of MLB to protect against hepatic IR injury was determined using hepatic IR model in mice. Then, the effect of MLB on IR-induced inflammatory response was detected in detail. We found that MLB exhibited protective effect from the beginning of 50 mg/kg and culminated at the doses of 100 and 200 mg/kg. The alanine aminotransferase and aspartate aminotransferase levels in MLB group were markedly decreased. Severe hepatocellular swelling/necrosis, sinusoidal/vascular congestion and inflammatory cell infiltration were seen and a large number of apoptotic cells were found in the liver samples from Saline group, while minimal damage and very few apoptotic cells were noted in the samples from MLB group. Kuppfer cells infiltration, myeloperoxidase activity and mRNA level of CD11b in MLB group was significantly decreased. Serum TNF-a and IL-6, and mRNA expression of CXCL-10 and ICAM-1 was markedly decreased in the samples from MLB group. Inflammatory signaling pathway activation was largely prevented in MLB group. MLB can significantly attenuate IR-induced hepatocellular damage and hepatocellular apoptosis by preventing inflammatory signaling pathways activation, inflammatory mediators expression and macrophage and neutrophil infiltration.

Topics: Alanine Transaminase; Animals; Apoptosis; Aspartate Aminotransferases; CD11b Antigen; Chemokine CXCL10; Disease Models, Animal; Drugs, Chinese Herbal; Inflammation Mediators; Intercellular Adhesion Molecule-1; Interleukin-6; Liver; Macrophages; Male; Mice; Mice, Inbred C57BL; Neutrophils; Peroxidase; Reperfusion Injury; Signal Transduction; Tumor Necrosis Factor-alpha

In human beings or animals, ischemia/reperfusion (I/R) injury of the liver may occur in many clinical conditions, such as circulating shock, liver transplantation and surgery and several other pathological conditions. I/R injury has a complex pathophysiology resulting from a number of contributing factors. Therefore, it is difficult to achieve effective treatment or protection by individually targeting the mediators. This study aimed at studying the effects of local somatothermal stimulation preconditioning on the right Qimen (LR14) on hepatic I/R injury in rats.. Eighteen male Sprague-Dawley rats were randomly divided into three groups. The rats were preconditioned with thermal tolerance study, which included one dose of local somatothermal stimulation (LSTS) on right Qimen (LR14) at an interval of 12 h, followed by hepatic ischemia for 60 min and then reperfusion for 60 min. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) have been used to assess the liver functions, and liver tissues were taken for the measurements such as malondialdehyde (MDA), glutathione (GSH), catalase (CAT), superoxidase dismutase (SOD), and myeloperoxidase (MPO).. The results show that the plasma ALT and AST activities were higher in the I/R group than in the control group. In addition, the plasma ALT and AST activities decreased in the groups that received LSTS. The hepatic SOD levels reduced significantly by I/R injury. Moreover, the hepatic MPO activity significantly increased by I/R injury while it decreased in the groups given LSTS.. Our findings show that LSTS provides a protective effects on the liver from the I/R injury. Therefore, LSTS might offer an easy and inexpensive intervention for patients who have suffered from I/R of the liver especially in the process of hepatotomy and hepatic transplantation.

Topics: Acupuncture Points; Alanine Transaminase; Animals; Aspartate Aminotransferases; Catalase; Glutathione; Hyperthermia, Induced; Ischemia; Ischemic Preconditioning; Liver; Liver Diseases; Male; Malondialdehyde; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase; Temperature

Ischaemia-reperfusion (I/R) injury is encountered in conditions that diminish intestinal blood flow. There is no clinically feasible technique available for mucosal preservation.. One hundred Wistar rats were subjected to intestinal ischaemia for 15 and 60 min (I15', I60'), followed by 1 and 7 days of reperfusion (R1d, R7d). Rats were subjected to ischaemia by clamping the superior mesenteric artery. Prostaglandin E1 (PGE1) (2.500 ng/kg intra-arterial bolus or 20 ng/kg intravenous infusion) was administered immediately prior to the commencement of the experimental period. Animals were divided into 20 groups: sham (laparotomy alone), sacrificed at 1 or 7 days; saline administration, 15 or 60 min of ischaemia, 1 or 7 days of reperfusion; prostaglandin E1 administration, 15 or 60 min of ischaemia, 1 or 7 days of reperfusion, each one for intra-arterial or intravenous administration. Ileal segments were excised and assessed for histopathological score, polymorphonuclear (PMN) leucocytes encountered and myeloperoxidase (MPO) activity measurement.. I/R caused deterioration of histological characteristics. Prophylactic administration of PGE1 resulted in a significant decrease in the histological score compared with the respective saline group (analysis of variance, P < 0.005). In groups treated with PGE1, PMN leucocyte infiltration was lower for the 60 min of ischaemia group (I60'/R1d *P = 0.026; I60'/R7d P = 0.015). I15'/R7d did not lead to a significant reduction in PMN infiltration (P = 0.061). Pretreatment with PGE1 attenuates MPO levels after intestinal I/R injury (P < 0.05). No differences were encountered between types of administration.. Results of this study showed that administration of prostaglandin E1 prevents I/R injury by diminishing histological damage parameters, inhibiting PMN leucocyte infiltration and attenuating MPO activity.

Topics: Alprostadil; Animals; Cytoprotection; Disease Models, Animal; Ileal Diseases; Ileum; Infusions, Intravenous; Injections, Intra-Arterial; Mesenteric Vascular Occlusion; Neutrophil Infiltration; Neutrophils; Peroxidase; Protective Agents; Rats; Rats, Wistar; Reperfusion Injury; Time Factors

The inflammatory response after hepatic ischemia reperfusion (I/R) contributes to liver dysfunction and failure after transplantation. Butyrate is a four-carbon fatty acid, normally produced by bacterial fermentation of fiber in mammalian intestines, with anti-inflammatory activities. The purpose of the present study was to investigate the protective effect of butyrate preconditioning, if any, against hepatic I/R injury in rats and the underlying mechanisms involved.. Male Sprague-Dawley rats were subjected to a partial (70%) hepatic ischemia for 60 min after pretreatment with either vehicle or butyrate, followed by 3, 6, and 24 h of reperfusion. Hepatic injury was evaluated by biochemical and histopathologic examinations. Neutrophil infiltration was measured by myeloperoxidase (MPO) activity. The expression of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) was measured by enzyme-linked immunosorbent assay (Elisa) and Real-time reverse-transcriptase polymerase chain reaction (RT-PCR). The expression of nuclear factor kappa B (NF-κB) p65 was determined by immunohistochemistry and Western blot analysis.. Butyrate treatment markedly improved hepatic function and histology, as indicated by reduced transaminase levels and ameliorated tissue pathologic changes. The expression of tumor necrosis factor-alpha, interleukin-6, and myeloperoxidase activity was attenuated by butyrate. Butyrate also reduced I/R-induced nuclear translocation of NF-κB p65 in Kupffer cells.. Our results suggest that butyrate alleviates I/R-induced liver injury, possibly by suppressing inflammatory factors production and preventing NF-κB activation in Kupffer cells.

Topics: Animals; Butyrates; Cell Nucleus; Hepatitis; Interleukin-6; Kupffer Cells; Liver; Liver Transplantation; Male; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; RNA, Messenger; Transcription Factor RelA; Transplantation Conditioning; Tumor Necrosis Factor-alpha

Despite successful revascularization, reperfusion after prolonged ischemia causes ischemia reperfusion (I/R) injury. Recruitment and activation of neutrophils is thought to be a key event causing I/R injury. We examined whether post-ischemic intra-arterial infusion of liposome-encapsulated hemoglobin (LEH), an artificial oxygen carrier without neutrophils, could reduce I/R injury in a rat transient middle cerebral artery occlusion (MCAO) model. Male Sprague-Dawley rats were subjected to 2-h MCAO and then were divided into three groups: (1) LEH group (n=7) infused with LEH (Hb concentration of 6g/dl, 10ml/kg/h) through the recanalized internal carotid artery for 2h, (2) vehicle group (n=8) infused with saline (10ml/kg/h) in the same manner as the LEH group, and (3) control group (n=9) subjected to recanalization only. After 24-h reperfusion, all rats were tested for neurological score and then sacrificed to examine infarct and edema volumes, myeloperoxidase (MPO) expression, matrix metalloproteinase-9 (MMP-9) expression and activity, and reactive oxygen species (ROS) production. Compared with the control group and the vehicle group, the LEH group showed a significantly better neurological score and significantly smaller infarct and edema volumes. MPO expression, MMP-9 expression and activity, and ROS production in the LEH group were also significantly lower than those in the control and vehicle groups. The results in the present study suggest that post-ischemic intra-arterial infusion of LEH can reduce I/R injury through reducing the effect of MMP-9, most likely produced by neutrophils. This therapeutic strategy may be a promising candidate to prevent I/R injury after thrombolysis and/or thromboectomy.

Topics: Aldehydes; Animals; Brain; Brain Ischemia; Carotid Artery, Internal; Edema; Hemoglobins; Humans; Infarction, Middle Cerebral Artery; Infusions, Intra-Arterial; Liposomes; Male; Matrix Metalloproteinase 9; Peroxidase; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Reperfusion Injury; Severity of Illness Index

Intestinal ischemia and reperfusion (I/R) is a potentially life-threatening disease, ensuing from various clinical conditions. Experimentally, either protective or detrimental roles have been attributed to 5-HT in the functional and morphological injury caused by mesenteric I/R. Recently, we proved the involvement of 5-HT2A receptors in the intestinal dysmotility and leukocyte recruitment induced by 45min occlusion of the superior mesenteric artery (SMA) followed by 24h reperfusion in mice. Starting from these premises, the aim of our present work was to investigate the role played by endogenous 5-HT in the same experimental model where 45min SMA clamping was followed by 5h reflow. To this end, we first observed that ischemic preconditioning before I/R injury (IPC+I/R) reverted the increase in 5-HT tissue content and in inflammatory parameters induced by I/R in mice. Second, the effects produced by intravenous administration of 5-HT1A ligands (partial agonist buspirone 10mgkg(-1), antagonist WAY100135 0.5-5mgkg(-1)), 5-HT2A antagonist sarpogrelate (10mgkg(-1)), 5-HT3 antagonist alosetron (0.1mgkg(-1)), 5-HT4 antagonist GR125487 (5mgkg(-1)) and 5-HT re-uptake inhibitor fluoxetine (10mgkg(-1)) on I/R-induced inflammatory response were investigated in I/R mice and compared to those obtained in sham-operated animals (S). Our results confirmed the significant role played by 5-HT2A receptors not only in the late but also in the early I/R-induced microcirculatory dysfunction and showed that blockade of 5-HT1A receptors protected against the intestinal leukocyte recruitment, plasma extravasation and reactive oxygen species formation triggered by SMA occlusion and reflow. The ability of α7 nicotinic receptor (α7nAchR) antagonist methyllycaconitine (5mgkg(-1)) to counteract the beneficial action provided by buspirone on I/R-induced neutrophil infiltration suggests that the anti-inflammatory effect produced by 5-HT1A receptor antagonism could be partly ascribed to the indirect activation of α7nAch receptors.

Topics: Aconitine; alpha7 Nicotinic Acetylcholine Receptor; Animals; Buspirone; Female; Heme Oxygenase-1; Interleukin-1beta; Intestinal Mucosa; Intestines; Malondialdehyde; Membrane Proteins; Mice; Nicotinic Antagonists; Peroxidase; Piperazines; Receptor, Serotonin, 5-HT1A; Reperfusion Injury; Serotonin; Serotonin 5-HT1 Receptor Agonists; Serotonin 5-HT1 Receptor Antagonists; Tumor Necrosis Factor-alpha

Objective It has been found that ulinastatin (UTI) can attenuate hepatic injury in a rat model of ischemia reperfusion (IR), but the specific mechanism is unclear. This study aims to investigate possible pathomechanism of ulinastatin in reducing the inflammatory response after hepatic IR. Methods A male sprague-dawley(SD) rat model of hepatic ischemia reperfusion injury was used. The rats were randomly divided into 4 groups on average, which were 0.9% saline and IR group as control, ulinastatin preconditioning (UPC) group, UPC+rHMGB1 (recombinant HMGB1) group and UPC +anti-HMGB1 group. Serum aminotransferases, TNF-α, IL-1 and Myeloperoxidase (MPO) levels were measured. Histopathology examination and apoptotic cell detection and the different expression of HMGB1 protein were also assessed. Results Serum levels of aminotransferases, cytokines and hepatic MPO in UPC and UPC+anti-HMGB1 groups were significantly lower than those in control group (p<0.05). Decreased histologic damage and apoptosis were also seen in these two groups (p<0.05). Conclusions HMGB1 expressions in UPC and UPC+anti-HMGB1 groups were significantly lower than those in the two control groups (p<0.05), pretreatment with ulinastatin attenuated liver IR injury by reducing HMGB1 expression through its anti-inflammatory effects.

Topics: Animals; Apoptosis; Aspartate Aminotransferases; Cytokines; Glycoproteins; HMGB1 Protein; Immunohistochemistry; Liver; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Transaminases; Trypsin Inhibitors

Congestion-reperfusion injury (CRI) is a common complication after living donor liver transplantation, which has not been fully understood. It causes more severe inflammatory response as compared with ischemia-reperfusion injury (IRI). Ischemic preconditioning (IPC) has been endowed with powerful protective properties toward IRI. This study aimed to investigate whether IPC also has a protective effect against CRI and potential underlying mechanisms.. Mice were randomly divided into sham operation, CRI, IPC-CRI, and congestion precondition (CPC-CRI) group. The hepatic vein of the left anterior hepatic lobe was occluded for 75 min followed by reperfusion in the CRI group. The blood inflow was previously clamped for 10 min followed by 10 min of reperfusion just before occluding the hepatic vein in the IPC-CRI group. To imitating IPC in the CPC-CRI group, 10 min of congestion followed by 10 min of reperfusion just before CRI was performed. The animals were sacrificed at 2, 6, 24, 48 h, and 7 d after reperfusion. The blood and liver samples were collected for hepatic function assay, histology, terminal deoxynucleotidyl transferase dUTP nick end labeling, myeloperoxidase, and real-time polymerase chain reaction analysis.. Mice in the CRI, IPC-CRI, and CPC-CRI group demonstrated elevated liver enzymes, histologic damage, cellular apoptosis, and inflammatory response compared with those in the sham operation group. Compared with the CRI group, mice in the IPC-CRI group expressed lower alanine transaminase activities (2 h: 839.2 ± 132.5 versus 384.2 ± 94.8, P < 0.01; and 6 h: 680 ± 142.4 versus 342.3 ± 99.7, P < 0.01) and lower myeloperoxidase levels (2 h: 7.1 ± 4.0 U/g versus 3.8 ± 1.6 U/g, P < 0.05; and 6 h: 8.1 ± 1.3 U/g versus 5.2 ± 3.0 U/g, P < 0.05). However, the alanine transaminase level in the CPC-CRI group was notably higher at 2 h (839.2 ± 132.5 versus 1087.5 ± 192.5, P < 0.05). Livers from mice in the IPC-CRI group showed better tissue integrity, diminished hepatocellular injury, and apoptosis at 2 and 6 h. The messenger RNA transcriptions of interleukin 1 and interleukin 6 were significantly lower after 2-24 h of reperfusion, whereas tumor necrosis factor α and monocyte chemoattractant protein 1 were significantly lower after 24 h of reperfusion in the IPC-CRI group.. IPC can significantly improve liver tolerance to CRI by attenuating neutrophil infiltration, proinflammatory cytokine formation, and hepatocytes apoptosis. This pretreatment strategy holds greater prospect of being translated into clinical use in living donor liver transplantation.

Topics: Alanine Transaminase; Animals; Apoptosis; Chemokines; In Situ Nick-End Labeling; Inflammation Mediators; Ischemic Preconditioning; Liver Diseases; Male; Mice; Mice, Inbred C57BL; Neutrophil Infiltration; Peroxidase; Random Allocation; Reperfusion Injury

Warm hepatic ischemia-reperfusion (I/R) injury can lead to multiorgan dysfunction. The aim of the present study was to investigate whether acute liver I/R does affect the function and/or structure of remote organs such as lung, kidney, and heart via modulation of extracellular matrix remodelling.. Male Sprague-Dawley rats were subjected to 30 min partial hepatic ischemia by clamping the hepatic artery and the portal vein. After a 60 min reperfusion, liver, lung, kidney, and heart biopsies and blood samples were collected. Serum hepatic enzymes, creatinine, urea, Troponin I and TNF-alpha, and tissue matrix metalloproteinases (MMP-2, MMP-9), myeloperoxidase (MPO), malondialdehyde (MDA), and morphology were monitored.. Serum levels of hepatic enzymes and TNF-alpha were concomitantly increased during hepatic I/R. An increase in hepatic MMP-2 and MMP-9 activities was substantiated by tissue morphology alterations. Notably, acute hepatic I/R affect the lung inasmuch as MMP-9 activity and MPO levels were increased. No difference in MMPs and MPO was observed in kidney and heart.. Although the underlying mechanism needs further investigation, this is the first study in which the MMP activation in a distant organ is reported; this event is probably TNF-alpha-mediated and the lung appears as the first remote organ to be involved in hepatic I/R injury.

Topics: Animals; Creatinine; Kidney; Liver; Lung; Male; Malondialdehyde; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Myocardium; Organ Specificity; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Troponin I; Tumor Necrosis Factor-alpha; Urea

There is increasing evidence that the effects of administered ATP sensitive potassium (KATP ) channel openers or blockers during ischaemia are still controversial in many organs/tissues. Testicular torsion detorsion which causes ischaemia-reperfusion (IR) injury, cannot be predicted, thus an effective drug should be administered during or after the ischaemia. The aim of this study was to examine whether the administration of KATP channel openers or blockers during ischaemia ameliorates IR injury in the testis. Eight-week-old male Sprague-Dawley rats were subjected to 2 h right testicular ischaemia followed by 24 h reperfusion. The selective mitochondrial (mito) KATP channel blocker, 5-hydroxydecanoate (5-HD) (40 mg/kg), the non-selective KATP channel blocker glibenclamide (5 mg/kg), the selective mito KATP channel opener diazoxide (10 mg/kg) and the non-selective KATP channel opener cromakalim (300 μg/kg) were administered intraperitoneally 15 min prior to the ischaemia or 75 min after the induction of ischaemia. Tissue damage was evaluated by malondialdehyde concentration, myeloperoxidase activity, histological evaluation and TdT-mediated dUTP nick end labelling assay in the testis. There was a significant increase in oxidative stress, neutrophil infiltration, histological damage and apoptosis in the testicular IR model. A significant reduction in the testicular IR injury was observed with the administration of glibenclamide, but not 5-HD, diazoxide or cromakalim during ischaemia. The administration of non-selective KATP channel blocker glibenclamide ameliorated the testicular IR injury. On the other hand, the selective mito KATP channel blocker, 5-HD and KATP channel openers did not reduce the testicular IR injury. These data suggest that blocking of the membrane KATP channel may have a protective effect during the testicular ischaemia. Glibenclamide could be an effective drug to manage the post-ischaemic injury caused by the testicular torsion-detorsion.

Topics: Animals; Apoptosis; Cromakalim; Decanoic Acids; Diazoxide; Glyburide; Hydroxy Acids; KATP Channels; Male; Malondialdehyde; Neutrophil Infiltration; Oxidative Stress; Peroxidase; Potassium Channel Blockers; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Spermatic Cord Torsion; Testis

We set out to investigate the microcirculatory consequences of hepatic ischemia-reperfusion (IR) injury and the effects of L-alpha-glycerylphosphorylcholine (GPC), a deacylated phospholipid derivative, on postischemic hepatocellular damage, with special emphasis on the expression of nicotinamide adenine dinucleotide phosphate oxidase type 4 (NOX4), which is predominantly expressed in hepatic microvessels.. Anesthetized male Sprague-Dawley rats were subjected to 60-min ischemia of the left liver lobes and 180-min reperfusion, with or without GPC treatment (50 mg/kg intravenously 5 min before reperfusion, n = 6 each). A third group (n = 6) served as saline-treated control. Noninvasive online examination of the hepatic microcirculation was performed hourly by means of modified spectrometry. Plasma tumor necrosis factor (TNF-α), high-mobility group box 1 protein (HMGB1), plasma aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase levels, tissue xanthine oxidoreductase (XOR) and myeloperoxidase (MPO) activities, and expressions of NOX2 and NOX4 proteins were determined.. Liver IR resulted in significant increases in NOX2 and NOX4 expressions and XOR and MPO activities, and approximately 2-fold increases in the levels of the inflammatory cytokines TNF-α and HMGB1. The microvascular blood flow and tissue oxygen saturation decreased by ∼20% from control values. GPC administration ameliorated the postischemic microcirculatory deterioration and reduced the liver necroenzyme levels significantly; the NOX4 expression, MPO activity, and HMGB1 level were also decreased, whereas the NOX2 expression, TNF-α level, and XOR activity were not influenced by GPC pretreatment.. NOX4 activation is a decisive component in the IR-induced microcirculatory dysfunction. Exogenous GPC ameliorates the inflammatory activation, and preserves the postischemic microvascular perfusion and liver functions, these effects being associated with a reduced hepatic expression of NOX4.

Topics: Animals; Glycerylphosphorylcholine; Liver; Liver Circulation; Male; Microcirculation; NADPH Oxidase 4; NADPH Oxidases; Peroxidase; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Xanthine Dehydrogenase

Intestinal ischemia-reperfusion (II/R) is associated with high morbidity and mortality. The aim of this study was to investigate the effects of osthole on lung injury and mortality induced by II/R.. A rat model of II/R was induced by clamping the superior mesenteric artery for 90 min followed by reperfusion for 240 min. Osthole was administrated intraperitoneally at 30 min before intestinal ischemia (10 or 50 mg/kg). The survival rate and mean arterial pressure were observed. Blood samples were obtained for blood gas analyses. Lung injury was assessed by the histopathologic changes (hematoxylin and eosin staining), lung wet-to-dry weight ratio, and pulmonary permeability index. The levels of reactive oxygen species, malondialdehyde, interleukin 6, and tumor necrosis factor α, as well as the activities of superoxide dismutase and myeloperoxidase in lung were measured.. The survival rate, ratio of arterial oxygen tension to fraction of inspired oxygen, and mean arterial pressure decreased significantly after II/R. Results also indicated that II/R-induced severe lung injury evidenced by increase in pathologic scores, lung wet-to-dry weight ratio, and pulmonary permeability index, which was accompanied by increases in the levels of pulmonary reactive oxygen species, malondialdehyde, interleukin 6, tumor necrosis factor α, and the pulmonary myeloperoxidase activity and a decrease in superoxide dismutase activity. Osthole could significantly ameliorate lung injury and improve the previously mentioned variables.. These findings indicated that osthole could attenuate the lung injury induced by II/R in rats, at least in part, by inhibiting inflammatory response and oxidative stress.

Topics: Acute Lung Injury; Animals; Blood Pressure; Calcium Channel Blockers; Coumarins; Disease Models, Animal; Interleukin-6; Lung; Male; Malondialdehyde; Organ Size; Oxidative Stress; Peroxidase; Pulmonary Gas Exchange; Rats; Rats, Wistar; Reactive Oxygen Species; Reperfusion Injury; Superoxide Dismutase; Tumor Necrosis Factor-alpha

To investigate the effects of ischemic postconditioning (IPostC) on pneumocyte apoptosis after lung ischemia/reperfusion injury in rats.. Adult male SD rats were randomly divided into 3 groups based upon the intervention (n = 8): control group (C), lung ischemic reperfusion group (LIR), LIR+ IPostC group (IPostC). At the end of the experiment, blood specimens drawn from the arteria carotis were tested for the content of malondialdehyde (MDA), the activity of superoxide dismutase (SOD) and myeloperoxidase (MPO); the pneumocyte apoptosis index (AI) was achieved by tennrminal deoxynucleotidyl transferase mediated dUTP nick end abeling (TUNEL); the expression of Bcl-2, Bax protein in lung tissue was accessed by quantitative immunohistochemistry (MHC) and Bcl-2, Bax mRNA by RT-PCR.. IPostC could significantly attenuate the MDA level, MPO activity and improve SOD activity in blood serum which was comparable to I/R and significantly reduced the number of TUNEL-positive cells compared with I/R group, expressed as Al (% total nuclei) from (39.0 +/- 3.46) to (8.0 +/- 0.88) (P < 0.01). The protein and mRNA expression of Bcl-2 and Bax showed that IPO significantly attenuated the ischemia/reperfusion-upregulated expression of Bax protein but improved the expression of Bcl-2 that improved the Bcl-2/Bax ratio (P < 0.01) .. IPostC may attenuate pneumocyte apoptosis in LIRI by up-regulating expression of Bcl-2/Bax ratio and by inhibiting oxidant generation and neutrophils filtration.

Topics: Alveolar Epithelial Cells; Animals; Apoptosis; bcl-2-Associated X Protein; Ischemic Postconditioning; Lung; Lung Injury; Male; Malondialdehyde; Peroxidase; Proto-Oncogene Proteins c-bcl-2; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase

To investigate the neuroprotective effects of Sulindac on the hippocampal complex after global cerebral ischemia/reperfusion (I/R) injury in rats.. Thirty one Sprague-Dawley rats were used, distributed into group I (sham) n:7 were used as control. For group II (n:8), III (n:8) and IV (n:8) rats, cerebral ischemia was performed via the occlusion of bilateral internal carotid artery for 45 minutes and continued with reperfusion process. 0.3 mL/kg/h 0.9 % sodium chloride was infused intraperitoneally to the Group II rats before ischemia, 5μg/kg/h/0.3 ml sulindac was infused intraperitoneally to the Group III rats before ischemia and 5μg/kg/h/0.3 ml sulindac was infused intraperitoneally to the Group IV rats after ischemia and before reperfusion process. The levels of MDA, GSH and MPO activity were measured in the left hippocampus tissue. The hippocampal tissue of all group members were taken for histopathological study.. The MDA and MPO levels increased from group I (control) to group II (I/R) (P<0.05) and decreased from group II (I/R) to group III (presulindac + I/R) and IV (postsulindac + I/R) (P<0.05). Beside these, the GSH levels decreased from group I (control) to group II (I/R) (P<0.05) and increased from group II (I/R) to group III (presulindac + I/R) and IV (postsulindac + I/R) (P<0.05).The number of apoptotic neurons increased from group I (control) to group II (I/R) (P<0.05) and decreased from group II (I/R) to group III (presulindac + I/R) and IV (postsulindac + I/R) (P<0.05).. The Sulindac may have neuroprotective effects on ischemic neural tissue to prevent the reperfusion injury after ischemia.

Topics: Animals; Apoptosis; Brain Ischemia; Cyclooxygenase Inhibitors; Disease Models, Animal; Glutathione; Hippocampus; Infusions, Parenteral; Malondialdehyde; Neuroprotective Agents; Oxidative Stress; Peroxidase; Rats, Sprague-Dawley; Reperfusion Injury; Reproducibility of Results; Sulindac

Ischemia-reperfusion injury (IRI) after lung transplantation remains a significant cause of morbidity and mortality. Lung IRI induces nitric oxide synthesis (iNOS) and reactive nitrogen species, decreasing nitric oxide bioavailability. We hypothesized that ischemia-induced iNOS intensifies with reperfusion and contributes to IRI-induced pulmonary arterial regulatory dysfunction, which may lead to early graft failure and cause pulmonary edema. The aim of this study was to determine whether ischemia-reperfusion alters inducible and endothelial nitric oxide synthase expression, potentially affecting pulmonary perfusion. We further evaluated the role of iNOS in post-transplantation pulmonary arterial disorder.. We randomized 32 Sprague-Dawley rats into two groups. The control group was given a sham operation whilst the experimental group received orthotropic lung transplants with a modified three-cuff technique. Changes in lung iNOS, and endothelial nitric oxide synthase expression were measured after lung transplantation by enzyme-linked immunosorbent assay (ELISA). Vasoconstriction in response to exogenous phenylephrine and vasodilation in response to exogenous acetylcholine of pulmonary arterial rings were measured in vitro as a measure of vascular dysfunction. To elucidate the roles of iNOS in regulating vascular function, an iNOS activity inhibitor (N6-(1-iminoethyl)-L-lysine, L-NIL) was used to treat isolated arterial rings. In order to test whether iNOS inhibition has a therapeutic effect, we further used L-NIL to pre-treat transplanted lungs and then measured post-transplantation arterial responses.. Lung transplantation caused upregulation of iNOS expression. This was also accompanied by suppression of both vasoconstriction and vasodilation of arterial rings from transplanted lungs. Removal of endothelium did not interfere with the contraction of pulmonary arterial rings from transplanted lungs. In contrast, iNOS inhibition rescued the vasoconstriction response to exogenous phenylephrine of pulmonary arterial rings from transplanted lungs. In addition, lung transplantation led to suppression of PaO2/FiO2 ratio, increased intrapulmonary shunt (Q s/Q t), and increase of lung wet to dry ratio (W/D), malondialdehyde and myeloperoxidase levels, all of which were reversed upon iNOS inhibition. Furthermore, inhibition of iNOS significantly rescued vascular function and alleviated edema and inflammatory cell infiltration in the transplanted lung.. Our data suggest that lung transplantation causes upregulation of iNOS expression, and pulmonary vascular dysfunction. iNOS inhibition reverses the post-transplantational pulmonary vascular dysfunction.

Topics: Animals; In Vitro Techniques; Lung; Lung Transplantation; Lysine; Male; Malondialdehyde; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Peroxidase; Phenylephrine; Pulmonary Artery; Rats, Sprague-Dawley; Reperfusion Injury; Vasoconstriction; Vasodilation

The intestinal lymph pathway plays an important role in the pathogenesis of organ injury following superior mesenteric artery occlusion (SMAO) shock. We hypothesized that mesenteric lymph reperfusion (MLR) is a major cause of spleen injury after SMAO shock. To test this hypothesis, SMAO shock was induced in Wistar rats by clamping the superior mesenteric artery (SMA) for 1 h, followed by reperfusion for 2 h. Similarly, MLR was performed by clamping the mesenteric lymph duct (MLD) for 1 h, followed by reperfusion for 2 h. In the MLR+SMAO group rats, both the SMA and MLD were clamped and then released for reperfusion for 2 h. SMAO shock alone elicited: 1) splenic structure injury, 2) increased levels of malondialdehyde, nitric oxide (NO), intercellular adhesion molecule-1, endotoxin, lipopolysaccharide receptor (CD14), lipopolysaccharide-binding protein, and tumor necrosis factor-α, 3) enhanced activities of NO synthase and myeloperoxidase, and 4) decreased activities of superoxide dismutase and ATPase. MLR following SMAO shock further aggravated these deleterious effects. We conclude that MLR exacerbates spleen injury caused by SMAO shock, which itself is associated with oxidative stress, excessive release of NO, recruitment of polymorphonuclear neutrophils, endotoxin translocation, and enhanced inflammatory responses.

Topics: Acute-Phase Proteins; Adenosine Triphosphatases; Animals; Carrier Proteins; Endotoxins; Intercellular Adhesion Molecule-1; Intestines; Lipopolysaccharide Receptors; Lymph; Male; Malondialdehyde; Membrane Glycoproteins; Mesenteric Artery, Superior; Mesenteric Vascular Occlusion; Nitric Oxide; Nitric Oxide Synthase; Peroxidase; Rats, Wistar; Reperfusion; Reperfusion Injury; Spleen; Superoxide Dismutase; Tumor Necrosis Factor-alpha

We investigated the function of major superoxide-generating enzymes after remote ischemic preconditioning (IPC) and hepatic ischemia-reperfusion (IR), with the specific aim of assessing the importance of the most relevant NADPH oxidase (NOX) isoforms, NOX2 and NOX4, in the mechanism of action.. 60-min partial liver ischemia was induced in Sprague-Dawley rats in the presence or absence of remote IPC (2 × 10-min limb IR), and hepatic microcirculatory variables were determined through intravital video microscopy and lightguide spectrophotometry during reperfusion. Inflammatory enzyme activities (myeloperoxidase (MPO) and xanthine oxidoreductase (XOR)), cytokine production (TNF-α and HMGB-1), liver necroenzyme levels (AST, ALT and LDH) and NOX2 and NOX4 protein expression changes (Western blot analysis) were assayed biochemically.. In this setting, remote IPC significantly decreased the IR-induced hepatic NOX2 expression, but the NOX4 expression remained unchanged. The remote IPC provided significant, but incomplete protection against the leukocyte-endothelial cell interactions and flow deterioration. Hepatocellular damage (AST, ALT and LDH release), cytokine levels, and XOR and MPO activities also diminished.. Remote IPC limited the IR-induced microcirculatory dysfunction, but the protective effect did not affect all NOX homologs (at least not NOX4). The residual damage and inflammatory activation could well be linked to the unchanging NOX4 activity.

Topics: Analysis of Variance; Animals; Blotting, Western; Cytokines; HMGB1 Protein; Ischemic Preconditioning; Liver; Membrane Glycoproteins; Microcirculation; Microscopy, Video; NADPH Oxidase 2; NADPH Oxidase 4; NADPH Oxidases; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Spectrophotometry; Tumor Necrosis Factor-alpha; Xanthine Dehydrogenase

To ascertain whether glutamine (Gln) pretreatment protects rats with obstructive jaundice from hepatic ischemia/reperfusion (I/R) injury and to determine the underlying molecular mechanisms.. An obstructive jaundice rat model was developed by bile duct ligation. On the first day after the operation, all rats were randomized into two groups and received oral Gln or normal saline (NS) daily for 7 days. Then both groups underwent a 15-min liver ischemia via the Pringle maneuver. Blood samples as well as liver and intestinal tissues were harvested and measured after 1, 6 and 24 h of reperfusion.. The results showed that the histological morphology of the liver and intestinal tissues significantly improved in the Gln group after I/R injury compared with the NS group. Serum proteins and enzymes associated with hepatic function also significantly improved in the Gln group. The level of glutathione increased and the levels of malondialdehyde and myeloperoxidase decreased in the Gln group. The levels of interleukin-1β and tumor necrosis factor-α decreased in the Gln group. Moreover, bcl-2 protein expression was upregulated and intercellular adhesion molecule 1 and bax protein expression downregulated in the Gln group; the caspase 3 mRNA level significantly increased in the Gln group.. The study demonstrates that preconditioning with Gln significantly improves hepatic structure and function after I/R injury in rats with obstructive jaundice. The protective effect of Gln was mediated by the inhibition of reactive oxygen species and inflammation as well as a reduction in hepatocyte apoptosis.

Topics: Animals; Apoptosis; Disease Models, Animal; Down-Regulation; Glutamine; Glutathione; Hepatocytes; Interleukin-1beta; Jaundice, Obstructive; Liver; Male; Malondialdehyde; Peroxidase; Rats; Rats, Wistar; Reactive Oxygen Species; Reperfusion Injury; Time Factors; Tumor Necrosis Factor-alpha; Up-Regulation

Ischemia-reperfusion injury (IRI) significantly contributes to graft dysfunction after liver transplantation. Natural killer (NK) cells are crucial innate effector cells in the liver and express tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a potent inducer of hepatocyte cell death. Here, we investigated if TRAIL expression on NK cells contributes to hepatic IRI.. The outcome after partial hepatic IRI was assessed in TRAIL-null mice and contrasted to C57BL/6J wild-type mice and after NK cell adoptive transfer in RAG2/common gamma-null mice that lack T, B, and NK cells. Liver IRI was assessed by histological analysis, alanine aminotransferase, hepatic neutrophil activation by myeloperoxidase activity, and cytokine secretion at specific time points. NK cell cytotoxicity and differentiation were assessed in vivo and in vitro.. Twenty-four hours after reperfusion, TRAIL-null mice exhibited significantly higher serum transaminases, histological signs of necrosis, neutrophil infiltration, and serum levels of interleukin-6 compared to wild-type animals. Adoptive transfer of TRAIL-null NK cells into immunodeficient RAG2/common gamma-null mice was associated with significantly elevated liver damage compared to transfer of wild-type NK cells. In TRAIL-null mice, NK cells exhibit higher cytotoxicity and decreased differentiation compared to wild-type mice. In vitro, cytotoxicity against YAC-1 and secretion of interferon gamma by TRAIL-null NK cells were significantly increased compared to wild-type controls.. These experiments reveal that expression of TRAIL on NK cells is protective in a murine model of hepatic IRI through modulation of NK cell cytotoxicity and NK cell differentiation.

Topics: Adoptive Transfer; Animals; Cell Death; Cell Differentiation; Cytokines; Granulocytes; Hepatocytes; Interleukin-6; Killer Cells, Natural; Liver; Mice; Mice, Inbred C57BL; Necrosis; Neutrophils; Oxidative Stress; Peroxidase; Reperfusion Injury; TNF-Related Apoptosis-Inducing Ligand; Transaminases

Cilostazol, a phosphodiesterase-III inhibitor, reportedly exhibits positive effects against ischemia/reperfusion (I/R)-induced injury in several models. However, its potential role against the renal I/R insult has not been elucidated. To test whether the PPAR-γ (of peroxisome proliferator activated receptor gamma) pathway is involved in the cilostazol effect, rats were randomized into sham, I/R, cilostazol (50 and 100 mg/kg per day, orally), pioglitazone (3 and 10 mg/kg per day, orally) and their combination at the low dose levels. Drugs regimens were administered for 14 days prior to the I/R induction. Pretreatment with cilostazol or pioglitazone provided significant protection against the I/R-induced renal injury as manifested by the attenuated serum levels of creatinine, blood urea nitrogen and cystatin C. Both drugs have also opposed the I/R-induced elevation in tissue contents/activity of neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (Κim-1), nuclear factor-κB, interleuκin-18, caspase-1, as well as malondialdehyde, iNOS, myeloperoxidase, ICAM-1 and VCAM-1. Nevertheless, the drugs increased both the PPAR-γ transcriptional activity and the content of glutathione. Furthermore, combining the two low doses of both drugs produced effects comparable to that of the high dose level of either drug, advocating the fortification of pioglitazone renoprotective effect when given concomitantly with cilostazol. In conclusion, cilostazol purveyed conceivable novel renoprotective mechanisms and alleviated incidents associated with acute renal injury either alone or in combination with pioglitazone partially via the elevation of PPAR-γ besides the amendment of the aforementioned biomarkers.

Topics: Acute Kidney Injury; Acute-Phase Proteins; Animals; Blood Urea Nitrogen; Caspase 1; Cell Adhesion Molecules; Cilostazol; Creatinine; Cystatin C; Dose-Response Relationship, Drug; Hypoglycemic Agents; Intercellular Adhesion Molecule-1; Interleukin-18; Kidney; Lipocalin-2; Lipocalins; Male; Nitric Oxide Synthase Type II; Peroxidase; Phosphodiesterase 3 Inhibitors; Pioglitazone; PPAR gamma; Protective Agents; Proto-Oncogene Proteins; Random Allocation; Rats, Wistar; Reperfusion Injury; Tetrazoles; Thiazolidinediones; Vascular Cell Adhesion Molecule-1

Inflammatory activation plays a vital role in the pathophysiological mechanisms of stroke and diabetes mellitus (DM), exerts the deleterious effects on the progression of the brain and leads to vascular damage in diabetic stroke. The objectives of this study were to investigate the effects of 8-O-acetyl shanzhiside methylester (ND01) on tumour necrosis factor-α (TNF-α)-stimulated SH-SY5Y cell line in vitro and the experimental ischaemic diabetic stroke model in vivo. TNF-α-stimulated SH-SY5Y cells were pre-incubated with ND01, then analysed protein expression. For in vivo experiment, the diabetic rats were subjected to middle cerebral artery occlusion (MCAO) for 30 min. followed by reperfusion for 23 hr. Treatment of SH-SY5Y cells with ND01 blocked TNF-α-induced nuclear transcription factor κB (NF-κB) activation and decreased high-mobility group box-1 (HMGB-1) expression. ND01 40 mg/kg demonstrated significant neuroprotective effect even after delayed administration at 4 hr after I/R. ND01 40 mg/kg attenuated the histopathological damage, decreased brain swelling, inhibited NF-κB activation and reduced HMGB-1 expression in ischaemic brain tissue. These data show that ND01 protects diabetic brain against I/R injury with a favourable therapeutic time-window by alleviating diabetic cerebral I/R injury and attenuating blood-brain barrier (BBB) breakdown, and its protective effects may involve HMGB-1 and NF-κB signalling pathway.

Topics: Animals; Anti-Inflammatory Agents; Blood-Brain Barrier; Brain Ischemia; Diabetes Mellitus, Experimental; Disease Models, Animal; Glucosides; HMGB1 Protein; Male; NF-kappa B; Peroxidase; Pyrans; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

To investigate the potential protective effects of Rosmarinic acid (RA) on rats exposed to ischaemia/reperfusion renal injury.. The prospective study was conducted at Abant Izzet Baysal University, Turkey, and comprised 21 male Spraque Dawley rats weighing 250-270g each. They were divided into three equal groups. Unilaterally nephrectomised rats were subjected to 60 minutes of left renal ischaemia followed by 60 minutes of reperfusion. Group 1 had sham-operated animals; group 2 had ischaemia/reperfusion untreated animals; and group 3 had ischaemia/reperfusion animals treated with rosmarinic acid. Serum creatinine, blood urea nitrogen, tissue malondialdehyde, glutathione peroxidase, superoxide dismutase and myeloperoxidase (MPO) activities, and light microscopic findings were evaluated. SPSS 17 was used for statistical analysis.. Treatment of rats with rosmarinic acid produced a reduction in the serum levels of creatinine and blood urea nitrogen compared to the other groups. However, no statistically significant difference was found. The levels of malondialdehyde and myeloperoxidase were decreased in the renal tissue of group 3, while glutathione peroxidose and superoxide dismutase levels remained unchanged. The injury score decreased in the treatment group rats compared to the untreated group. Rosmarinic acid significantly decreased focal glomerular necrosis, dilatation of Bowman's capsule, degeneration of tubular epithelium, necrosis in tubular epithelium, and tubular dilatation.. Rosmarinic acid prevented ischaemia/reperfusion injury in the kidneys by decreasing oxidative stress.

Topics: Animals; Blood Urea Nitrogen; Cinnamates; Creatinine; Depsides; Kidney Diseases; Male; Malondialdehyde; Nephrectomy; Oxidative Stress; Peroxidase; Prospective Studies; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Rosmarinic Acid

Granulocyte colony-stimulating factor (G-CSF) is a pharmacologic agent inducing neutrophil mobilization and a new candidate for neuroprotection and neuroregeneration in stroke. Its effects when used in combination with tissue plasminogen activator (tPA) were explored during the acute phase of ischemic stroke.. We used a middle cerebral artery occlusion (MCAO) model of cerebral ischemia, associated with treatment with tPA, in male spontaneously hypertensive rats (SHR). Granulocyte colony-stimulating factor (G-CSF; 60 μg/kg) was injected just before tPA. Neutrophil response in peripheral blood and in the infarct area was quantified in parallel to the infarct volume. Protease matrix metallopeptidase 9 (MMP-9) release from circulating neutrophils was analyzed by immunochemistry and zymography. Vascular reactivity and hemorrhagic volume in the infarct area was also assessed.. Twenty four hours after ischemia and tPA, G-CSF administration induced a significant increase of neutrophils in peripheral blood (P <0.05). At 72 hours post-ischemia, G-CSF was significantly associated with an increased risk of hemorrhage in the infarct area (2.5 times more likely; P <0.05) and significant cerebral endothelium-dependent dysfunction. Ex vivo, an increased MMP-9 release from neutrophils after tPA administration correlated to the increased hemorrhagic risk (P <0.05). In parallel, G-CSF administration was associated with a decreased neutrophil infiltration in the infarct area (-50%; P <0.05), with a concomitant significant neuroprotective effect (infarct volume: -40%; P <0.05).. We demonstrate that G-CSF potentiates the risk of hemorrhage in experimental stroke when used in combination with tPA by inducing neutrophilia. This effect is concomitant to an increased MMP-9 release from peripheral neutrophils induced by the tPA treatment. These results highlight the potential hemorrhagic risk of associating G-CSF to thrombolysis during the acute phase of stroke.

Topics: Animals; Brain Infarction; Disease Models, Animal; Drug Administration Schedule; Endothelium; Fibrinolytic Agents; Granulocyte Colony-Stimulating Factor; Hemorrhage; Infarction, Middle Cerebral Artery; Male; Matrix Metalloproteinase 9; Neutrophil Infiltration; Neutrophils; Peroxidase; Rats; Rats, Inbred SHR; Reperfusion Injury; Statistics, Nonparametric; Time Factors; Tissue Plasminogen Activator

This study is a biochemical investigation of the effect of etoricoxib, a selective cyclooxygenase (COX)-2 inhibitor, on ischemia/reperfusion (I/R) injury experimentally induced in rat ovaries.. Experimental animals were divided into four groups: (i) ovarian ischemia/reperfusion (IRG); (ii) 30 mg/kg etoricoxib + ovarian ischemia/reperfusion (EIRG-30); (iii) 60 mg/kg etoricoxib + ovarian ischemia/reperfusion (EIRG-60); and (iv) a sham operation (SG) control group.. The results showed levels of malondialdehyde in the IRG, EIRG-30, EIRG-60 and SG group ovarian tissue of 20.2 ± 3.4, 11.2 ± 3.2, 5.5 ± 1.9 and 3.8 ± 1.5 μmol/g protein, respectively. Myeloperoxidase activity for these groups was 24.2 ± 6.7, 13 ± 2.4, 4 ± 1.8 and 3.5 ± 1.9 U/g protein, and total glutathione levels were 1.6 ± 0.8, 4.5 ± 1.9, 6.5 ± 1.9 and 7.5 ± 2.4 nmol/g protein, respectively. COX-1 activity in IRG, EIRG-30, EIRG-60 and SG group rat ovarian tissue was 5.0 ± 2.8, 12.2 ± 2.4, 16.7 ± 2.8 and 17.5 ± 4.7 U/mg protein, and COX-2 activity was 18.3 ± 2.7, 3.5 ± 1, 1.8 ± 0.7 and 0.7 ± 0.3 U/mg protein, respectively.. Etoricoxib prevented oxidative damage induced with I/R in rat ovarian tissue. This property of etoricoxib suggests that it can be clinically beneficial in the prevention of damage that may arise with reperfusion by detorsion for the protection of the ovaries against torsion.

Topics: Animals; Cyclooxygenase 1; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Etoricoxib; Female; Glutathione; Malondialdehyde; Membrane Proteins; Ovary; Peroxidase; Pyridines; Rats, Wistar; Reperfusion Injury; Sulfones

Mast cell (MC) degranulation contributes to the protection mediated by ischemic preconditioning (IPC); however, the precise mechanisms underlying this protection remain largely unknown. Mast cell carboxypeptidase A (MC-CPA) is released solely from MCs and plays a critical role in degrading toxins and endothelin 1 (ET-1). The present study sought to explore whether MC-CPA is involved in the process of IPC in a rodent model of small intestinal ischemia reperfusion (IIR) injury.. IIR injuries were induced in Sprague-Dawley rats by clamping the superior mesenteric artery for 60 min followed by reperfusion for 2 h. One cycle of 10 min intestinal ischemia and 10 min of reperfusion was used in the IPC group, and the MC stabilizer cromolyn sodium and MC potato carboxypeptidase inhibitor were administered before the start of IPC. At the end of experiment, intestine tissue was obtained for assays of the MC-CPA3, tumor necrosis factor-α, interleukin-6, and ET-1 contents and myeloperoxidase activities. Intestinal histologic injury scores and MC degranulation were assessed. Apoptosis indices and cleaved caspase- 3 protein expressions were quantified.. IIR resulted in severe injury, as evidenced by significant increases in injury scores and MC-CPA3, tumor necrosis factor-α, interleukin-6, and ET-1 contents that were accompanied with concomitant elevations in cleaved caspase 3 expression, apoptosis indices, and myeloperoxidase activities. IPC induced a significant increase in MC-CPA3, induced MC degranulation, and attenuated IIR injury by downregulating IIR-induced biochemical changes, whereas cromolyn sodium and potato carboxypeptidase inhibitor abolished the IPC-mediated changes.. These data suggest that IPC protected against IIR injury via the MC degranulation-mediated release of MC-CPA.

Topics: Animals; Apoptosis; Carboxypeptidases A; Cell Degranulation; Endothelin-1; Interleukin-6; Intestinal Mucosa; Intestine, Small; Ischemic Preconditioning; Male; Mast Cells; Peroxidase; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

We evaluated the role of sildenafil in a rat liver ischemia-reperfusion model. Forty male rats were randomly allocated in four groups. The sham group underwent midline laparotomy only. In the sildenafil group, sildenafil was administered intraperitoneally 60 minutes before sham laparotomy. In the ischemia-reperfusion (I/R) group, rats were subjected to 45 minutes of hepatic ischemia followed by 120 minutes of reperfusion, while in the sild+I/R group rats were subjected to a similar pattern of I/R after the administration of sildenafil, 60 minutes before ischemia. Two hours after reperfusion, serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured and histopathological examination of the lobes subjected to ischemia as well as TUNEL staining for apoptotic bodies was performed. Additionally, myeloperoxidase (MPO) activity and the expression of intercellular adhesion molecule-1 (ICAM-1) were analyzed. Serum markers of hepatocellular injury were significantly lower in the sild+I/R group, which also exhibited lower severity of histopathological lesions and fewer apoptotic bodies, as compared to the I/R group. The I/R group showed significantly higher MPO activity and higher expression of ICAM-1, as compared to the sild+I/R group. Use of sildenafil as a preconditioning agent in a rat model of liver I/R exerted a protective effect.

Topics: Alanine Transaminase; Animals; Apoptosis; Aspartate Aminotransferases; Gene Expression Regulation; In Situ Nick-End Labeling; Intercellular Adhesion Molecule-1; Liver; Liver Diseases; Male; Peroxidase; Piperazines; Purines; Rats, Wistar; Reperfusion Injury; RNA, Messenger; Sildenafil Citrate; Staining and Labeling; Sulfones

Intestinal ischemia-reperfusion injury is one of the main factors leading to multiple organ failure after resuscitation of prolonged hemorrhagic shock; however, the current conventional fluid resuscitation still cannot effectively reduce intestinal injury caused by prolonged hemorrhagic shock. To investigate the effect of ECMO resuscitation on alleviating intestinal ischemia-reperfusion injury in a prolonged hemorrhagic shock rabbit model. Thirty New Zealand white rabbits were randomly divided into three groups: control group, conventional fluid resuscitation group, and ECMO resuscitation group. The prolonged hemorrhagic shock model was established by keeping the arterial blood pressure from 31 to 40 mmHg for 3 h through the femoral artery bleeding, and performing the resuscitation for 2 h by conventional fluid resuscitation and ECMO resuscitation, respectively. Chiu's score of intestinal injury, serum lactate and TNF-α levels, intestinal mucosamyeloperoxidase (MPO) activity, intercellular adhesion molecule (ICAM-1), and Claudin-1expression were detected. The mean arterial blood pressure in Group 2 was significantly higher after resuscitation than in Group 1, but serum lactate and inflammatory cytokines TNF-α level were significantly lower. And Chiu's score of intestinal injury and myeloperoxidase (MPO) activity level and ICAM-1 expression were significantly lower in the ECMO resuscitation group, in which the Claudin-1 levels were significantly increased. ECMO resuscitation for the prolonged hemorrhagic shock improves tissue perfusion and reduces the systemic inflammation, and thus alleviates intestinal damage caused by prolonged hemorrhagic shock.

Topics: Animals; Blood Pressure; Claudin-1; Disease Models, Animal; Extracorporeal Membrane Oxygenation; Intercellular Adhesion Molecule-1; Intestinal Mucosa; Intestines; Lactic Acid; Male; Peroxidase; Rabbits; Reperfusion Injury; Severity of Illness Index; Shock, Hemorrhagic; Tumor Necrosis Factor-alpha

To evaluate the effects of acupuncture (Ac) and electroacupuncture (EAc) on oxidative stress and inflammation in testis torsion/detorsion (T/D) model in rats.. Thirty male Wistar rats were randomized into five groups. G1 Group (Sham) served as control. The remaining groups were submitted to spermatic cord torsion (720°) for 3 hours, followed by detorsion and reperfusion for 4 hours. Before detorsion G3, G4 and G5 rats were treated with Ac, EAc 2Hz and EAc 10 Hz, respectively, applied to acupoint Gulai (S-29) bilaterally under anesthesia for 5 minutes. Next, the testes were detorsioned and reperfused for 4 hours. Afterwards, blood samples and the right testis were collected for biochemical assays: reduced Glutathione (GSH), Malonaldehyde (MDA), Myeloperoxidase (MPO).. EAc stimulation (2 and 10 Hz) promoted significant increase in concentrations of GSH in plasma and testis of G4-G5 rats, compared with G1. There was significant increase of tissue MDA in groups G4-G5 and plasma MDA in all groups, compared with G1. There was a significant reduction in MPO activity in groups G4-G5 compared with G1.. Electroacupuncture stimulation (2 and 10 Hz) attenuates oxidative stress and inflammatory response in rats subjected to testicular torsion/detorsion.

Topics: Acupuncture Points; Animals; Electroacupuncture; Glutathione; Lipid Peroxidation; Male; Malondialdehyde; Oxidative Stress; Peroxidase; Random Allocation; Rats, Wistar; Reperfusion Injury; Reproducibility of Results; Spermatic Cord Torsion; Testis; Time Factors; Treatment Outcome

The purpose of this study was to investigate the effect of etoricoxib on oxidative injury induced with ischemia-reperfusion (I/R) in rat kidney tissue in terms of biochemistry and immunohistochemistry. Male Albino Wistar rats were divided into renal I/R (RIR), 50 mg/kg etoricoxib+RIR (ETO-50), 100 mg/kg etoricoxib+RIR (ETO-100) and sham operation (SG) groups. Animals in the ETO-50 and ETO-100 groups were given etoricoxib by the oral route at dosages of 50 and 100 mg/kg, respectively. The RIR and SG groups were given distilled water as solvent. One hour after drug administration, 1h of ischemia and 3h of reperfusion were applied to the left kidneys of all rats (apart from SG) under 25 mg/kg thiopental sodium anesthesia. At the end of that time, kidneys were extracted and biochemical and immunohistochemical analyses were performed. Etoricoxib reduced, in a dose-dependent manner, levels of MDA, MPO and COX-2 that normally rise with I/R in rat kidney tissues. Etorixicob did not alter COX-1 activity at 50 and 100 mg/kg doses, but significantly prevented loss of tGSH in tissues with I/R. In addition, Bcl-2' gene expression inhibited with I/R was prevented in renal tubular and glomerular cells. Furthermore, etoricoxib significantly decreased the caspase-3 gene expression which increased with I/R. Etoricoxib significantly prevented I/R injury in a dose-dependent manner. The results of this study show that etoricoxib treatment could decrease kidney injury during IR.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Caspase 3; Cells, Cultured; Cyclooxygenase 2; Disease Models, Animal; Etoricoxib; Gene Expression Regulation; Humans; Kidney; Male; Malondialdehyde; Oxidative Stress; Peroxidase; Proto-Oncogene Proteins c-bcl-2; Pyridines; Rats; Rats, Wistar; Reperfusion Injury; Sulfones

The aim of our study was to determinate the impact of dipeptide (alanyl-glutamine) administration on inflammatory and proliferative changes in jejunal mucosa after acute mesenteric ischemia.. Male Wistar rats (n=30) were divided into three groups: ischemia/reperfusion (IR) group which undergoes 60min of mesenteric ischemia and 1 or 24h of reperfusion (IR1, IR24, n=12). Groups with dipeptide administration (D+IR1, D+IR24, Dipeptiven con inf., i.v., 0.75 g/kg) prior to IR injury were followed by 1 and 24h of reperfusion. At the end of reperfusion period jejunal bioptic samples were obtained for histological (H&E), histochemical (Alcian blue) and immunohistochemical (anti-PCNA, anti-MPO) evaluations.. Our results pointed out a significant (p<0.001) increase of histopathological injury score in IR1 group compared to D+IR1 group. Immunohistochemical evaluation showed that MPO-positivity was significantly increased in IR groups after 1 (p<0.001) as well as 24h of reperfusion (p<0.01) compared to dipeptide pretreated groups. Proliferative/reparatory rate was assessed using anti-PCNA antibody and showed a significant increase (p<0.01) in PCNA cell positivity in lamina propria in dipeptide treated group compared to IR group.. In conclusion we may suggest that administration of alanyl-glutamine dipeptide prior to IR injury may help to protect small intestine and its mucous membrane integrity against insult such as intestinal ischemic/reperfusion injury presents.

Topics: Animals; Apoptosis; Dipeptides; Immunohistochemistry; Inflammation; Intestinal Mucosa; Jejunum; Male; Mesenteric Ischemia; Peroxidase; Proliferating Cell Nuclear Antigen; Rats, Wistar; Reperfusion Injury

To verify the effects of N-acetylcysteine (NAC) administered before and after ischaemia in an animal model of lung ischaemia-reperfusion (IR) injury.. Twenty-four Wistar rats were subjected to an experimental model of selective left pulmonary hilar clamping for 45 min followed by 2 h of reperfusion. The animals were divided into four groups: control group (SHAM), ischaemia-reperfusion, N-acetylcysteine-preischaemia (NAC-Pre) and NAC-postischaemia (NAC-Post). We recorded the haemodynamic parameters, blood gas analysis and histology. We measured the thiobarbituric acid reactive substances concentration; the expression of superoxide dismutase (SOD), inducible nitric oxide synthase (iNOS), nitrotyrosine, cleaved caspase 3, nuclear factor κB (NF-κB), NF-kappa-B inhibitor alpha (IκB-α), tumour necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β); myeloperoxidase activity (MPO).. No significant differences were observed in the haemodynamic parameters, blood gas analysis and SOD activity among the groups. Lipid peroxidation was significantly higher in the IR and NAC-Pre groups (P < 0.01). The expression of nitrotyrosine, cleaved caspase 3, NF-κB, IκB-α, TNF-α and IL-1β were significantly higher in the IR group when compared with the SHAM and NAC groups (P < 0.01). The NAC-Pre group showed a significantly higher expression of these proteins when compared with the SHAM and NAC-Post groups (P < 0.05). After reperfusion, the expression of iNOS increased almost uniformly in all groups when compared with the SHAM group (P < 0.01). The histological analysis showed fewer inflammatory cells in the NAC groups.. The intravenous administration of NAC demonstrated protective properties against lung IR injury. The use of NAC immediately after reperfusion potentiates its protective effects.

Topics: Acetylcysteine; Administration, Intravenous; Animals; Anti-Inflammatory Agents; Antioxidants; Caspase 3; Cytoprotection; Disease Models, Animal; Hemodynamics; I-kappa B Kinase; Inflammation Mediators; Interleukin-1beta; Lipid Peroxidation; Lung; Lung Injury; NF-kappa B; Nitric Oxide Synthase Type II; Oxidative Stress; Peroxidase; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase; Time Factors; Tumor Necrosis Factor-alpha; Tyrosine

To investigate the effects of nuclear factor-κB activation inhibitor dehydroxymethylepoxyquinomicin (DHMEQ) on cardiac ischemia reperfusion injury in a transplantation model.. Hearts of C57BL/6 mice were flushed and stored in cold Bretschneider solution for 8 h and then transplanted into syngeneic recipient. Some mice were administrated intraperitoneally with DHMEQ (8 mg/kg) 1 h before reperfusion. For inhibition of Hmgb1, mice were treated with glycyrrhizin at 250 mg/kg prior to reperfusion.. DHMEQ decreased cardiomyocyte apoptosis and recruitment of neutrophils and macrophages. Troponin T (TnT) production on 24 h after myocardial IR injury was reduced by DHMEQ treatment. Cardiac output at 60 mmHg of afterload pressure was significantly increased in hearts with DHMEQ treatment (IR+DHMEQ: 58.6 ± 5.75 ml/min; IR: 25.9 ± 4.1 ml/min; P < 0.05). Furthermore, DHMEQ suppressed high mobility group protein (Hmgb1) expression. And the Caspase 3 activity, the number of TUNEL-positive cardiomyocytes and infiltrated neutrophil in cardiac allograft were markedly decreased with Hmgb1 inhibitor treatment.. Nuclear factor-κB activation inhibitor DHMEQ attenuates ischemia reperfusion injury in a cardiac transplantation model and it may be a suitable agent for the protection of the cardiac against ischemia reperfusion injury.

Topics: Animals; Apoptosis; Benzamides; Cyclohexanones; Glycyrrhizic Acid; Heart Transplantation; HMGB1 Protein; Male; Mice, Inbred C57BL; Myocardium; Myocytes, Cardiac; Neutrophil Infiltration; NF-kappa B; Peroxidase; Reperfusion Injury; Troponin T

In this study, we investigated the protective effect and mechanism of curcumin on a rat model of intestinal ischemia/reperfusion (I/R), which induces an acute liver lesion.. Curcumin was injected into rats in the curcumin groups through left femoral vein. The same volume of vehicle (0.9% normal saline) was injected into sham and I/R groups. Blood and liver tissue were gathered for serological and histopathological determination.. Intestinal I/R led to severe liver injury manifested as a significant increase in serum AST and ALT levels; all of those were reduced by treatment with curcumin. Simultaneously, the activity of SOD in liver decreased after intestinal I/R, which was increased by curcumin treatment. On the other hand, curcumin reduced MPO activity of liver tissue, as well as serum IL-6 and TNF-α levels observably. This is in parallel with the decreased level of liver intercellular cell adhesion molecule-1 (ICAM-1) and nuclear factor-κB (NF-κB) expression.. Our findings suggest that curcumin treatment attenuates liver lesion induced by intestinal I/R, attributable to the antioxidative and anti-inflammatory effect via inhibition of the NF-κB pathway.

Topics: Acute Disease; Alanine Transaminase; Animals; Aspartate Aminotransferases; Curcumin; Disease Models, Animal; Intercellular Adhesion Molecule-1; Interleukin-6; Liver; Liver Diseases; Male; NF-kappa B; Peroxidase; Protective Agents; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Signal Transduction; Superoxide Dismutase

To investigate the effects of ischemia/reperfusion on rat submandibular glands without denervation and the possible protective effects of ischemia preconditioning on the glands that experienced ischemia/reperfusion, in-situ ischemia/reperfusion and ischemia preconditioning experimental models of submandibular glands of healthy male Wistar rats were conducted. For ischemia/reperfusion groups, the glands were subjected to 90 min of ischemia without denervation, followed by 1, 12, 24, or 72 h of reperfusion. Ischemia preconditioning was achieved by 3 min of ischemia following 3 min of reperfusion, performed three times before ischemia/reperfusion. Salivary secretion, histological changes, alterations of tight junctions, myeloperoxidase activity, cellular apoptosis, and reactive oxygen species levels were detected. In ischemia/reperfusion glands, rising acute-inflammation responses, reduced tight-junction width, and increased myeloperoxidase activity, reactive oxygen species levels, and apoptotic cell numbers were observed, along with secretory dysfunction, especially at 1 and 12 h post-reperfusion, which seemed to gradually return to normal by 72 h post-reperfusion. In contrast, ischemia preconditioning showed the potential to ameliorate the injury-stress responses caused by ischemia/reperfusion. Our study revealed that ischemia/reperfusion could cause a series of injury-stress responses and ultimately lead to hyposecretion, independently of the parasympathetic nerve supply, which might play an important role in the early-phase dysfunction of the transplanted glands. Ischemia preconditioning could protect the involved glands and improve ischemia/reperfusion-induced hyposecretion.

Topics: Animals; Apoptosis; Disease Models, Animal; In Situ Nick-End Labeling; Ischemic Preconditioning; Male; Microscopy, Electron, Transmission; Monocytes; Neutrophils; Peroxidase; Random Allocation; Rats; Rats, Wistar; Reactive Oxygen Species; Reperfusion Injury; Saliva; Salivary Ducts; Secretory Rate; Submandibular Gland; Tight Junctions; Time Factors

Ischemia-reperfusion (IR) has been reported to be associated with augmented reactive oxygen radicals and cytokines. Currently, we aimed to examine the influence of fluoxetine, which is already used as a preoperative anxiolytic, in the context of IR induced by occlusion of infrarenal abdominal aorta (60 min of ischemia) and its effects on renal oxidative status, inflammation, renal function, and cellular integrity in reperfusion (120 min post-ischemia). Male rats were randomly assigned as control, IR, and pretreated groups. The pretreated group animals received fluoxetine (20 mg/kg, i.p.) once daily for 3 days. Renal tissue oxidative stress, myeloperoxidase activity, proinflammatory cytokines (tumor necrosis factor-α, interleukin-1β, interleukin-6), histology, and function were assessed. As an anti-inflammatory cytokine, interleukin-10 was also assessed. IR led to a significant increase in lipid hydroperoxide, malondialdehyde, and pro-oxidant antioxidant balance and decrease in superoxide dismutase activity and ferric reducing/antioxidant power level (p < 0.05), but fluoxetine was able to restore these parameters. High concentrations of tumor necrosis factor-α, interleukin-1β, interleukin-6, and myeloperoxidase activity caused by IR were significantly decreased in kidney tissue with fluoxetine. In addition, interleukin-10 levels were high in fluoxetine pretreated group. IR resulted in disrupted cellular integrity, infiltration of tissue with leukocytes, and decreased serum creatinine-urea levels (p < 0.05). Fluoxetine significantly restored impaired redox balance and inflammation parameters of rats subjected to IR to baseline values. This beneficial effect of fluoxetine on redox balance might be addressed to an improvement in renal function.

Topics: Acute Kidney Injury; Animals; Anti-Inflammatory Agents; Antioxidants; Cytokines; Drug Evaluation, Preclinical; Fluoxetine; Ischemia; Kidney; Male; Oxidation-Reduction; Oxidative Stress; Peroxidase; Rats, Sprague-Dawley; Reperfusion Injury

Toll-like receptor 2 (TLR2) recognizes conserved molecular patterns associated with both gram-negative and gram-positive bacteria, and detects some endogenous ligands. Previous studies demonstrated that in ischemia-reperfusion (I/R) injury of the small intestine, the TLR2-dependent signaling exerted preventive effects on the damage in young mice, but did not have a significant effect in neonatal mice. We investigated the role of TLR2 in adult ischemia-reperfusion injury in the small intestine. Wild-type and TLR2 knockout mice at 16 weeks of age were subjected to intestinal I/R injury. Some wild-type mice received anti-Ly-6G antibodies to deplete circulating neutrophils. In wild-type mice, I/R induced severe small intestinal injury characterized by infiltration by inflammatory cells, disruption of the mucosal epithelium, and mucosal bleeding. Compared to wild-type mice, TLR2 knockout mice exhibited less severe mucosal injury induced by I/R, with a 35%, 33%, and 43% reduction in histological grading score and luminal concentration of hemoglobin, and the numbers of apoptotic epithelial cells, respectively. The I/R increased the activity of myeloperoxidase (MPO), a marker of neutrophil infiltration, and the levels of mRNA expression of tumor necrosis factor-α (TNF-α), intercellular adhesion molecule-1 (ICAM-1), and cyclooxygenase-2 (COX-2) in the small intestine of the wild-type mice by 3.3-, 3.2-, and 13.0-fold, respectively. TLR2 deficiency significantly inhibited the I/R-induced increase in MPO activity and the expression of mRNAs for TNF-α and ICAM-1, but did not affect the expression of COX-2 mRNA. I/R also enhanced TLR2 mRNA expression by 2.9-fold. TLR2 proteins were found to be expressed in the epithelial cells, inflammatory cells, and endothelial cells. Neutrophil depletion prevented intestinal I/R injury in wild-type mice. These findings suggest that TLR2 may mediate I/R injury of the small intestine in adult mice via induction of inflammatory mediators such as TNF-α and ICAM-1.

Topics: Animals; Apoptosis; Cyclooxygenase 2; Epithelial Cells; Gene Expression Regulation; Humans; Inflammation; Intercellular Adhesion Molecule-1; Intestine, Small; Mice; Mice, Knockout; Neutrophil Infiltration; Peroxidase; Reperfusion Injury; Signal Transduction; Toll-Like Receptor 2; Tumor Necrosis Factor-alpha

To explore the protective eff ect of minocycline on hepatic ischemia-reperfusion injury (IRI) in rats and the underlying mechanisms.. A total of 54 male Sprague-Dawley rats were randomly divided into 3 groups: the sham-operated group (control group), the ischemic-reperfusion (IR group), and the minocycline preconditioning group (n=18 per group). The rats in the minocycline preconditioning group were given minocycline (45 mg/kg) by gastric irrigation at 36 h before operation and then were subsequently administered with minocycline (22.5 mg/kg) at every 12 h. Th e rats were sacrifi ced at 2, 6, 24 h after reperfusion. The serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were measured. HE staining of liver tissues was performed to detect the histological changes, and the degree of liver IRI according to Suzuki score were calculated. The levels of malondialdehyde (MDA) and myeloperoxidase (MPO) were determined by spectrophotometer; the mRNA expression of tumor necrosis factor-α (TNF-α) and interleukin-1 beta (IL-1β) in the liver were measured by real-time PCR; Dickkopf-1 (DKK-1) and beta-catenin (β-catenin) protein expression in the liver were detected by Western blot.. After 2, 6, 24 h reperfusion, compared with the IR group, the liver function (ALT, AST and LDH) in the minocycline group was significantly improved (all P<0.05); the Suzuki's scores and the levels of hepatic TNF-α and IL-1β mRNA were significantly decreased (all P<0. 05); the MDA and MPO levels the liver were decreased (both P<0.05); the protein expression of hepatic DKK-1 was decreased (P<0.05), while the protein expression of β-catenin was increased (P<0.05).. Minocycline can alleviate the ischemic-reperfusion injury mainly through reducing oxidative stress and inhibiting the release of pro-inflammatory cytokines depends on the activation of the Wnt/β-catenin signaling pathway in the liver.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; beta Catenin; Intercellular Signaling Peptides and Proteins; Interleukin-1beta; Ischemic Preconditioning; L-Lactate Dehydrogenase; Liver; Male; Malondialdehyde; Minocycline; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Real-Time Polymerase Chain Reaction; Reperfusion Injury; Tumor Necrosis Factor-alpha

Rosmarinic acid (RosmA) demonstrates antioxidant and anti-inflammatory properties. We investigated the effect of RosmA on liver ischemia/reperfusion injury. Rats were submitted to 60 min of ischemia plus saline or RosmA treatment (150 mg/kg BW intraperitoneally) followed by 6 h of reperfusion. Hepatocellular injury was evaluated according to aminotransferase activity and histological damage. Hepatic neutrophil accumulation was also evaluated. Oxidative/nitrosative stress was estimated by measuring the reduced glutathione, lipid hydroperoxide and nitrotyrosine levels. Endothelial and inducible nitric oxide synthase (eNOS/iNOS) and nitric oxide (NO) were assessed with immunoblotting and chemiluminescence assays. Hepatic tumor necrosis factor-alpha (TNF-α) and interleukin-1beta mRNA were assessed using real-time PCR, and nuclear factor-kappaB (NF-κB) activation was estimated by immunostaining. RosmA treatment reduced hepatocellular damage, neutrophil infiltration and all oxidative/nitrosative stress parameters. RosmA decreased the liver content of eNOS/iNOS and NO, attenuated NF-κB activation, and down-regulated TNF-α and interleukin-1beta gene expression. These data indicate that RosmA exerts anti-inflammatory and antioxidant effects in the ischemic liver, thereby protecting hepatocytes against ischemia/reperfusion injury. The mechanisms underlying these effects may be related to the inhibitory potential of RosmA on the NF-κB signaling pathway and the reduction of iNOS and eNOS expressions and NO levels, in addition to its natural antioxidant capability.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Cinnamates; Depsides; Glutathione; Interleukin-1beta; Lipid Peroxidation; Liver Diseases; Liver Function Tests; Male; Neutrophil Infiltration; Nitric Oxide; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Rosmarinic Acid; Tumor Necrosis Factor-alpha

To investigate the effects of terminal ileostomy on bacterial translocation (BT) and systemic inflammation after intestinal ischemia/reperfusion (I/R) injury in rats.. Thirty-two rats were assigned to either the sham-operated group, I/R group, I/R + resection and anastomosis group, or the I/R + ileostomy group. The superior mesenteric artery was occluded for 60 min. After 4 h, tissue samples were collected for analysis. BT was assessed by bacteriologic cultures, intestinal permeability and serum levels of endotoxin; systemic inflammation was assessed by serum levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-10, as well as by the activity of myeloperoxidase (MPO) and by intestinal histopathology.. Intestinal I/R injury not only caused morphologic damage to ileal mucosa, but also induced BT, increased MPO activity and promoted the release of TNF-α, IL-6, and IL-10 in serum. BT and ileal mucosa injuries were significantly improved and levels of TNF-α and IL-6 in serum were decreased in the I/R + ileostomy group compared with the I/R + resection and anastomosis group.. Terminal ileostomy can prevent the detrimental effects of intestinal I/R injury on BT, intestinal tissue, and inflammation.

Topics: Animals; Bacterial Translocation; Biomarkers; Disease Models, Animal; Ileostomy; Ileum; Inflammation; Inflammation Mediators; Interleukin-10; Interleukin-6; Male; Permeability; Peroxidase; Rats, Sprague-Dawley; Reperfusion Injury; Time Factors; Tumor Necrosis Factor-alpha

This study evaluated the effects of N-acetylcysteine as a scavenger of radical oxygen species on liver injury as a remote organ after skeletal muscle ischemia reperfusion.. Twenty male Wistar rats were allocated randomly into two experimental groups: ischemia reperfusion (I/R) and ischemia reperfusion + N-acetylcysteine (I/R+NAC). All animals were undergone 2h of ischemia by occlusion femoral artery and 24h of reperfusion. Rats that were treated with N-acetylcysteine given intravenously at a dose of 150 mg/kg, immediately before reperfusion. Serum levels of aspartate aminotransferase (AST), and alanine aminotransferase (ALT) were measured. Livers were harvested for histopathological and biochemical studies. Liver tissue malondialdehyde (MDA), glutathione (GSH) and myeloperoxidase (MPO) activity were assayed.. The ALT and AST values were significantly lower in I/R+NAC group. Hepatic MDA level and MPO activity were significantly increased in I/R group. The levels of GSH in liver tissue were significantly depressed by ischemia reperfusion. Liver histopathologic study in I/R group showed enlarged sinusoids, sinusoidal congestion, cytoplasmic vacuolation, cellular degenerative changes and necrosis. Histopathologically, there was a significant difference between two groups.. Histopatological and biochemical results have shown that N-acetylcysteine was able to protect liver from skeletal muscle ischemia reperfusion injury.

Topics: Acetylcysteine; Alanine Transaminase; Animals; Aspartate Aminotransferases; Free Radical Scavengers; Glutathione; Liver Diseases; Male; Malondialdehyde; Muscle, Skeletal; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Ischemia reperfusion injury (IRI) is a leading cause of acute kidney injury (AKI) in both native and transplanted kidneys. The objective of the present study was to evaluate whether low-molecular-weight fucoidan (LMWF) could attenuate renal IRI in an animal model and in vitro cell models and study the mechanisms in which LMWF protected from IRI.. Male mice were subjected to right renal ischemia for 30 min and reperfusion for 24 h, or to a sham operation with left kidney removed. Kidneys undergone IR showed characteristic morphological changes, such as tubular dilatation, and brush border loss. However, LMWF significantly corrected the renal dysfunction and the abnormal levels of MPO, MDA and SOD induced by IR. LMWF also inhibited the activation of MAPK pathways, which consequently resulted in a significant decrease in the release of cytochrome c from mitochondria, ratios of Bax/Bcl-2 and cleaved caspase-3/caspase-3, and phosphorylation of p53. LMWF alleviated hypoxia-reoxygenation or CoCl(2) induced cell viability loss and ΔΨm dissipation in HK2 renal tubular epithelial cells, which indicates LMWF may result in an inhibition of the apoptosis pathway through reducing activity of MAPK pathways in a dose-dependent manner.. Our in vivo and in vitro studies show that LMWF ameliorates acute renal IRI via inhibiting MAPK signaling pathways. The data provide evidence that LMWF may serve as a potential therapeutic agent for acute renal IRI.

Topics: Acute Kidney Injury; Animals; Apoptosis; bcl-2-Associated X Protein; Blotting, Western; Caspase 3; Cell Line; Cell Survival; Cobalt; Cytochromes c; Humans; Male; Malondialdehyde; MAP Kinase Signaling System; Membrane Potential, Mitochondrial; Mice; Mice, Inbred C57BL; Molecular Weight; Peroxidase; Phosphorylation; Polysaccharides; Proto-Oncogene Proteins c-bcl-2; Reperfusion Injury; Superoxide Dismutase; Tumor Suppressor Protein p53

Our aim was to explore the therapeutic effects of peripheral blood-derived endothelial progenitor cells (PB-EPC) in cardiac ischemia-reperfusion infarction models in rats and in in vitro culture systems.. Rat models of ischemia reperfusion and myocardial infarction were developed using male, Sprague-Dawley rats. Cardiomyocyte and endothelial cell cultures were also established. Therapeutic effects of PB-EPCs were examined in vivo and in vitro in both models. Rats underwent either cardiac ischemia-reperfusion (n = 40) or infarction (n = 56) surgeries and were transplanted with genetically modified EPCs. Treatment efficacy in the ischemia-reperfusion group was measured by infarct size, myocardial contraction velocity, and myeloperoxidase activity after transplantation. Cardiomyocyte survival and endothelial cell apoptosis were investigated in vitro. Vascular growth-associated protein expression and cardiac function were evaluated in the myocardial infarction group by western blot and echocardiography, respectively.. Infarct size and myeloperoxidase activity were significantly decreased in the ischemia-reperfusion group, whereas myocardial contractility was significantly increased in the EPC and Tβ4 groups compared with that in the control group. In contrast, no differences were found between EPC + shRNA Tβ4 and control groups. Rates of cardiomyocyte survival and endothelial cell apoptosis were significantly higher and lower, respectively, in the EPC and Tβ4 groups than in the control group, whereas no differences were found between the EPC + shRNA Tβ4 and control group. Four weeks after myocardial infarction, cardiac function was significantly better in the EPC group than in the control group. Expressions of PDGF, VEGF, and Flk-1 were significantly higher in EPC group than in control group.. Study findings suggest that PB-EPCs are able to protect cardiomyocytes from ischemia-reperfusion or infarction-induced damage via a Tβ4-mediated mechanism. EPCs may also provide protection through increased expression of proteins involved in mediating vascular growth. Autologous peripheral-blood-derived EPCs are readily available for efficient therapeutic use without the concerns of graft rejection.

Topics: Analysis of Variance; Animals; Apoptosis; Blotting, Western; Cell Survival; Disease Models, Animal; Endothelial Cells; Hematopoietic Stem Cells; Hemodynamics; Infarction; Intercellular Signaling Peptides and Proteins; Male; Myocardial Contraction; Myocytes, Cardiac; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Stem Cell Transplantation; Thymosin

To evaluate the effects of different-time ischemic preconditioning (IPC) schemes on the ischemia-reperfusion (I/R) injury in moderate to severe hepatocirrhosis in rats and to identify the optimal time window of IPC.. A total of 90 male SD rats with moderate to severe hepatocirrhosis were randomly divided into 5 groups (IR group, 5-10 min-IPC group, 8-10 min-IPC group, 10-10 min-IPC group and 15-10 min-IPC group), in which the liver was preconditioned by IPC of various durations, and then subjected to I/R injury in the last four groups. Thirty-six normal (non-cirrhotic) SD rats were divided into 2 groups (IR group and 10-10 min-IPC group). Ischemia-reperfusion injury was induced by clamping of the portal triad for 30 min followed by reperfusion for 30 min. Hepatocellular viability was assessed by measuring the concentration of ALT and AST in serum. The concentration of NO in serum and those of MDA, MPO, and SOD in the liver tissue were also assessed at 1h, 4h, and 24h after the operation respectively.. After 30-30min of I/R, the levels of ALT and AST were significantly elevated in the IR group and the groups under IPC, but the elevations were significantly lower in the 5-10 min-IPC group and the 8-10 min-IPC group, especially at 4h after I/R (P<0.05). The levels of MDA and MPO in liver tissue were lower in the 5-10 min-IPC and 8-10min-IPC groups than in the rest of the IPC groups and IR group in the cirrhotic rats, and the level of SOD was higher (P <0.05). The level of serum NO was significantly higher in the 5-10 min-IPC and 8-10min-IPC groups than in the rest of the cirrhotic groups (P <0.05).. The 5-10 min through 8-10 min-IPC achieves the highest protective effect on the I/R injury of moderate to severe hepatocirrhosis. With the aggravation of liver cirrhosis, the pre-implementation time has been shortened. Thus, IPC of 5-10min may be effective for severe liver cirrhosis.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Ischemic Preconditioning; Liver; Liver Cirrhosis; Male; Malondialdehyde; Nitric Oxide; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase; Time Factors

Paraplegia due to ischemia/reperfusion (I/R) injury of the spinal cord is a devastating and undesired complication of thoraco-abdominal aortic surgery. Unidentified clots cause a variety of thromboembolic events and deteriorate the severity of ischemia. We investigated the effect of the degree of anticoagulation on spinal cord I/R injury and whether heparin is protective against I/R injury beside its anticoagulant properties.. Twenty-eight rats were randomly assigned to four groups (n=7 per group) as G1 (no aortic occlusion and heparin administration), G2 (45 min aortic occlusion; no heparin administration), G3 (45 min aortic occlusion; 400 IU/kg heparin to keep activated clotting time (ACT) level around 200 sec), and G4 (45 min aortic occlusion; 800 IU/kg heparin to keep ACT level around 600 sec). After neurologic evaluation at the 48th hour of reperfusion, lumbar spinal cords were removed for histopathologic evaluation and immunohistochemical staining for HSP70 (heat shock protein 70), interleukin-6 and myeloperoxidase (MPO).. The Motor Deficit Index (MDI) scores were lowest in G1 group (p < 0.05) and the MDI scores of G3 and G4 were significantly lower than G2 group (p < 0.05). The neuronal degeneration in G3 was significantly lower than the other groups, respectively (p = 0.03). Histopathological evaluation showed no significant intergroup differences in terms of the degree of edema and inflammatory response. There was no statistically significant difference found among the groups in terms of HSP70 staining, IL-6 staining or the degree of MPO staining.. Protection of spinal cord from I/R injury requires a multimodal management. We should not miss out the importance of adequate anticoagulation in thoraco-abdominal surgical procedures. Furthermore, the recently discovered anti-inflammatory property of glycosaminoglycans, including heparin, deserves to be investigated.

Topics: Animals; Anti-Inflammatory Agents; Anticoagulants; Heparin; HSP70 Heat-Shock Proteins; Interleukin-6; Male; Motor Activity; Neuroprotective Agents; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Spinal Cord; Spinal Cord Ischemia

The aim of this study was to compare the ischaemia and reperfusion phases of two tourniquet application models (Group 1: expressing the blood by a sterile rubber bandage and Group 2: elevation of the limb for several minutes) using an analysis of ischaemia/reperfusion parameters and blood pH. Sixteen New Zealand rabbits were used. Muscle samples were extracted from the triceps surae; at phase A (baseline: just before tourniquet application), phase B (ischaemia: 3h after tourniquet inflation) and phase C (2h after tourniquet deflation). Nitrite, nitrate, reduced glutathione, myeloperoxidase, malondyaldehyde were measured in the samples. Blood pH was also measured at each phase. Group 2 had significantly decreased nitrite (p=0.007) and nitrate (p=0.01) levels compared to Group 1 while passing from phase A to phase B. The pH decrease through the phases was significant within Group 1 (p=0.006) and was not significant within Group 2 (p=0.052). Lower levels of NO metabolites nitrate and nitrite, result from tourniquet use with incomplete venous blood expression by elevation. Also, with this technique severe acidosis is less likely to occur than when a tourniquet is used with expression of the venous blood by rubber bandage. These findings may help in the decision of which tourniquet technique is to be used for potentially long operations which may exceed 2h.

Topics: Acidosis; Animals; Biomarkers; Ischemia; Malondialdehyde; Muscle, Skeletal; Nitrates; Nitrites; Orthopedic Procedures; Peroxidase; Rabbits; Reperfusion Injury; Tourniquets

The present study was aimed to investigate the protective effects of different-time-ischemic preconditioning on the reperfusion injury in fatty livers in rats, and to elucidate the mechanisms underlying the protective effects and the optimal safe ischemic preconditioning time on the hepatic IR injury in steatotic livers.. A rat fatty liver model was established by high-fat diet feeding. We investigated the changes in the concentration of AST, ALT, LDH and NO in the serum, and of MDA, SOD, and MPO in the liver samples in response to different ischemic preconditioning times and ischemia-reperfusion injury. Histological analysis was performed to evaluate the results of the hepatic fatty infiltration. 1) At 24 h after 15 min ischemic preconditioning with 10 min reperfusion (15 min +10 min IP), the extent and area of the necrosis was markedly higher in the fatty liver samples with respect to IR, compared to the normal liver samples. 2) In response to the treatment of 5/8 min +10 min IP, the fatty liver group showed lower levels of serological indicators and liver MDA and MPO compared to the other groups, while the SOD activity of the fatty liver group was significantly higher than the other groups (p<0.05). Compared to the corresponding IR group, all IP groups showed a significantly higher serum NO concentration (p<0.05). Among the fatty liver groups, the 5/8 min+10 min IP group showed the highest NO concentration (p<0.05).. Fat infiltration could aggravate the ischemia-reperfusion injury in the rat liver. Furthermore, ischemic preconditioning could increase the tolerance of the fatty liver, which was induced by the high-fat diet, to hepatic ischemia-reperfusion injury in rats. The protocol of 5/8 min +10 min IP was the optimal regimen for the treatment of moderate and severe fatty livers.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Fatty Liver; Ischemic Preconditioning; L-Lactate Dehydrogenase; Liver; Male; Malondialdehyde; Nitric Oxide; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Hyperglycemia exacerbates renal ischemia-reperfusion (IR) injury via aggravated inflammatory response and excessive production of reactive oxygen species. This study aimed to investigate the ability of propofol, a known antioxidant, to protect kidneys against IR injury in hyperglycemic rats in comparison with normoglycemic rats.. Sixty rats were randomly assigned to four groups: normoglycemia-etomidate, normoglycemia-propofol, hyperglycemia-etomidate, and hyperglycemia-propofol. Anesthesia was provided with propofol or etomidate depending on the group. Also, the rats received 1.2 g/kg dextrose or the same volume of normal saline depending on the group. Renal ischemia was induced for 25 min. The rats were killed, and samples were collected 65 min after starting intravenous anesthetics (sham) and 15 min and 24 h after reperfusion injury to compare the histologic degree of renal tubular damage and levels of inflammatory markers and enzymes related to reactive oxygen species.. Compared with etomidate, propofol significantly attenuated tubular damage after reperfusion in hyperglycemic rats. Also, tubular damage was greater under hyperglycemia compared with normoglycemia in the etomidate group, whereas it was similar in the propofol group. Propofol preserved superoxide dismutase level and attenuated the increase in levels of myeloperoxidase, interlukin-1β, and tumor necrosis factor-α after reperfusion compared with etomidate especially in hyperglycemic rats. Propofol also attenuated the production of inducible nitric oxide synthase and phosphorylation of inhibitor of κB and nuclear factor-κB after reperfusion, which were more prominent under hyperglycemia.. Propofol conveyed renoprotection against IR injury by preserved antioxidation ability and attenuated inflammatory response, which were more prominent under hyperglycemia.

Topics: Anesthetics, Intravenous; Animals; Antioxidants; Comorbidity; Disease Models, Animal; Etomidate; Hyperglycemia; Interleukin-1beta; Kidney; Kidney Tubules; Male; NF-kappa B; Peroxidase; Propofol; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Reperfusion Injury; Superoxide Dismutase; Tumor Necrosis Factor-alpha

Our objective was to determine the role of toll-like receptor 4 (TLR4) in uterine ischemia/reperfusion (I/R)-induced fetal growth restriction (FGR). Pregnant TLR4-deficient and wild-type mice were subjected to I/R or a sham procedure. Fetal and placental weights were recorded and tissues were collected. Pep-1 (inhibits low-molecular-weight hyaluronan (LMW-HA) binding to TLR4) was used to determine whether LMW-HA-TLR4 interaction has a role in FGR. TLR4-deficient mice exhibited significantly lower baseline fetal weights compared with wild-type mice (P<0.05), along with extensive placental calcification that was not present in wild-type mice. Following I/R, fetal and placental weights were significantly reduced in wild-type (P<0.05) but not in TLR4-deficient mice. However, I/R increased fetal loss (P<0.05) only in TLR4-deficient mice. Corresponding with the reduced fetal weights, uterine myeloperoxidase activity increased in wild-type mice (P<0.001), indicating an inflammatory response, which was absent in TLR4-deficient mice. TLR4 was shown to have a regulatory role for two anti-inflammatory cytokines: interferon-B1 decreased only in wild-type mice (P<0.01) and interleukin-10 increased only in TLR4-deficient mice (P<0.001), in response to I/R. Pep-1 completely prevented I/R-induced FGR (P<0.001), indicating a potential role for the endogenous TLR4 ligand LMW-HA in I/R-induced FGR. In conclusion, uterine I/R in pregnancy produces FGR that is dependent on TLR4 and endogenous ligand(s), including breakdown products of HA. In addition, TLR4 may play a role in preventing pregnancy loss after uterine I/R.

Topics: Animals; Biomarkers; Calcinosis; Cytokines; Female; Fetal Death; Fetal Growth Retardation; Fetal Weight; Hyaluronic Acid; Ligands; Mice; Mice, Inbred C3H; Mice, Mutant Strains; Mutant Proteins; Organ Size; Peroxidase; Pregnancy; Pregnancy Complications; Reperfusion Injury; Toll-Like Receptor 4; Uterine Diseases; Uterus

Perinatal asphyxia is an important cause of injury to fetal tissues such as the brain, heart, liver and gastrointestinal system. Fetal skin has also been shown to be vulnerable to intrauterine injury after intrauterine ischaemia/reperfusion (I/R) injury.. To examine the effect of dexamethasone on fetal skin in intrauterine I/R injury in rats.. The response of rat fetal skin to I/R injury and maternal dexamethasone treatment were assessed by determining thiobarbituric acid reactive substances (TBARS), and myeloperoxidase (MPO) and nitric oxide (NO) metabolites. We also examined the ultrastructural changes of fetal skin. Bilateral utero-ovarian artery clamping was performed to produce ischaemia for 30 min in rats at day 19 of pregnancy, and reperfusion was achieved by removing the clamps for 60 min before fetal tissue was collected. The treatment group was given dexamethasone intraperitoneally 20 min before I/R was performed.. TBARS, MPO and NO all increased significantly in fetal rat skin after I/R injury. Levels of TBARS, MPO and NO were significantly lower in the dexamethasone-treated group than in the I/R-only group. I/R injury produced ultrastructural damage in the epidermis. Oedema and mitochondrial damage were less severe in the dexamethasone-treated group.. Maternal treatment with dexamethasone may have a protective effect on fetal skin in cases of I/R injury.

Topics: Animals; Anti-Inflammatory Agents; Dexamethasone; Disease Models, Animal; Female; Fetal Diseases; Ischemia; Nitric Oxide; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Skin

Recently, one of the rare sugars, D-allose, has received attention from many researchers because of its availability for mass production and its various physiological functions. Among these, an antioxidative effect has been strongly suggested. In this study, we investigated whether this effect is also applicable to the field of skin surgery.. In ischemia-reperfusion injury model using the rat abdominal skin island flap (male Wistar rats, n = 110), D-allose was injected intravenously 15 min before 8-h ischemia. The survival area (%) was measured by digital photographic assessment 1 wk after surgery, and multiple comparisons (Fisher's protected least significant difference) were carried out. Histopathological examination (neutrophilic infiltration into dermis in hematoxylin and eosin stain) and immunostaining (of ectodermal dysplasia-1 (ED1)-positive cells/flap) were assessed. Myeloperoxidase (MPO) activity in the skin flap (sampling at the time of 8 h after reperfusion) was measured spectrophotometrically, and Student t-test was performed.. D-allose extended the survival of the remaining flaps, and a dose greater than 30 mg (0.1 mg/g) was necessary to be effective. The flap survival rates in the 30, 60, and 150 mg groups were significantly higher than that in the control (saline) group: 75.87 ± 5.90, 79.27 ± 7.81, and 77.87 ± 6.20 versus 50.53 ± 9.66, respectively (P < 0.05). ED1-positive cells/flap in 60 mg of D-allose and control (saline) were 78 ± 25.7 versus 124 ± 15.8, respectively (P = 0.08). The MPO activity in the D-allose 60 mg group was 0.40 ± 0.04, and that in the control (saline) was 0.72 ± 0.12. D-allose significantly reduced the skin tissue MPO activity (P < 0.05) compared with that in the control (saline) group.. We proved that D-allose has a reducing effect against ischemia-reperfusion injury on the skin island flap model, and the mechanism is related to inhibiting the activity of neutrophils in the skin tissues. Compared with chemo-synthetic materials, rare sugars are safer for our bodies as well as the environment; therefore, this rare sugar project is expected to lead to the development of a safer antioxidant for skin flap surgery.

Topics: Abdomen; Animals; Antioxidants; Dose-Response Relationship, Drug; Glucose; Male; Models, Animal; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Skin; Surgical Flaps

Renal ischemia-reperfusion (I/R) injury is a primary cause of acute renal failure that results in high mortality. This study aimed to investigate the effect of osthole, a natural coumarin derivative, on renal I/R injury in a rat model.. Rats were randomly allocated to the sham operation + vehicle, I/R + vehicle, and I/R + osthole groups. Renal I/R injury was induced by clamping the left renal artery for 45 min followed by 12 h of reperfusion and a contralateral nephrectomy. Osthole (40 mg/kg) was intraperitoneally injected 30 min before inducing I/R. Renal function and histological damage were determined subsequently. Myeloperoxidase activity, monocyte/macrophage infiltration, as well as tumor necrosis factor-α, IL-1β, and activated p38 mitogen-activated protein kinase expression in kidneys were also assessed.. Osthole treatment significantly ameliorated I/R-induced renal functional and morphological injuries. Moreover, osthole treatment attenuated myeloperoxidase activity, monocyte/macrophage infiltration, and tumor necrosis factor-α, IL-1β, and activated p38 mitogen-activated protein kinase expression in kidneys.. Osthole treatment ameliorates renal I/R injury by inhibiting inflammatory responses in kidneys. Thus, osthole may represent a novel practical strategy to prevent renal I/R injury.

Topics: Acute Kidney Injury; Animals; Calcium Channel Blockers; Coumarins; Disease Models, Animal; Gene Expression Regulation, Enzymologic; Inflammation; Interleukin-1beta; Kidney; Male; Monocytes; p38 Mitogen-Activated Protein Kinases; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

We examined the effect of egualen, a stable azulene derivative, against gastric damage induced by ischemia/reperfusion (I/R), gastric bleeding induced by double antiplatelet therapy with aspirin (ASA) plus clopidogrel, and small intestinal damage generated by loxoprofen, and investigated the possible mechanisms involved in its protective action. Male C57BL/6 mice or SD rats were used under urethane anesthesia (gastric lesions) or in a conscious (intestinal lesions) state. I/R-induced gastric injury was produced in mice by clamping the celiac artery for 30 min, followed by reperfusion for 60 min. Gastric bleeding was induced in rats by luminal perfusion with 25 mM ASA+50 mM HCl for 2 hours in the presence of clopidogrel (30 mg/kg). To produce small intestinal lesions the rats were given loxoprofen (60 mg/kg) p.o. and killed 24 hours later. Egualen was given i.d. 60 min before I/R or ASA perfusion, while given p.o. twice 30 min before and 6 hours after loxoprofen. Egualen significantly prevented the I/R-induced gastric damage, and the effect was equivalent to that of seratrodast (TXA2 antagonist). This agent also significantly suppressed gastric bleeding induced by ASA plus clopidogrel, similar to PGE2. Likewise, egualen significantly prevented loxoprofen-induced damage in the small intestine, accompanied by an increase in the secretion of mucus and suppression of bacterial invasion as well as iNOS expression. These results suggest that egualen has a prophylactic effect against various lesions in the gastrointestinal mucosa, probably through its characteristic pharmacological properties, such as TXA2 antagonistic action, local mucosal protection, and stimulation of mucus secretion.

Topics: Animals; Aspirin; Azulenes; Benzoquinones; Clopidogrel; Gastric Mucosa; Gastrointestinal Hemorrhage; Gastrointestinal Tract; Heptanoic Acids; Male; Mice; Mice, Inbred C57BL; Mucus; Nitric Oxide Synthase Type II; Peptic Ulcer; Peroxidase; Phenylpropionates; Platelet Aggregation Inhibitors; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sesquiterpenes; Ticlopidine

Rutin, a flavonoid commonly present in onions, apples and tea, has been suggested to have a variety of pharmacological activities, including immunomodulator, anti-inflammatory and antioxidant activities.. The present study was to examine the protective effects of rutin on gastric mucosal damage induced by gastric ischemia-reperfusion (I/R) in rats.. Rutin (50, 100, 200 mg/kg) was administered intragastrically for five consecutive days before ischemia. Sixty minutes after the last administration of rutin, under anesthesia, the celiac artery was clamped for 30 min, and then the clamp was removed for 60 min reperfusion. After reperfusion, the stomach was removed for biochemical and histological examinations.. As compared with the I/R group (116.7 ± 21.5), administration of rutin at doses of 50, 100 and 200 mg/kg significantly prevented the increase of gastric mucosal injury index induced by gastric I/R (73.4 ± 14.8, 65.9 ± 9.6 and 26.9 ± 5.7, respectively). ED50 value was 138.7 mg/kg. Moreover, rutin at doses of 50, 100 and 200 mg/kg showed an inhibition on the increased myeloperoxidase (24.6, 41.3 and 53.1% reduction) activity and malondialdehyde levels (27.4, 40.3 and 50.7% reduction) in gastric mucosa. Also, the elevation of inducible NO synthase (iNOS) activity as well as the decrease of constitutive NO synthase (cNOS) in the gastric mucosa were significantly prevented by rutin pretreatment.. These results suggested that rutin has a protective effect against gastric mucosal injury induced by gastric I/R and that the gastroprotection was related to the NOS/NO pathway and its antioxidant activity.

Topics: Animals; Antioxidants; Dose-Response Relationship, Drug; Gastric Mucosa; Male; Malondialdehyde; Nitric Oxide; Nitric Oxide Synthase Type II; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Rutin

To explore the role of myeloperoxidase (MPO) and tumor necrosis factor-α (TNF-α) in myocardial injury induced by hind-limb ischemia-reperfusion (IR) in rats.. Rat models of bilateral hindlimb IR established using a tourniquet were randomized into 9 groups, including a normal control group normal, 2 ischemic groups with hindlimb ischemia for 2 and 4 h, and 6 IR groups with a 4-h ischemia followed by reperfusion for 0.5, 2, 4, 6, 12, and 24 h. The plasma and myocardial levels of MPO and TNF-α in each group were measured, and the myocardial expression of TNF-α was determined with immunohistochemistry.. Compared with the normal control group, the rats with a 2-h ischemia showed significantly increased levels of MPO and TNF-α in the plasma and myocardium. Compared with those in rats with a 4-h ischemia, the plasma and myocardial MPO levels increased significantly at 0.5 and 2 h of reperfusion, respectively; the plasma TNF-α level increased significantly at 4 h of reperfusion and myocardial TNF-α level decreased obviously at 12 h; plasma levels of MPO and TNF-α both significantly decreased at 24 h. The plasma MPO and TNF-α and myocardial TNF-α reached the peak levels at 4 h of reperfusion, and the peak myocardial MPO level occurred at 6 h. Immunohistochemistry showed that TNF-α positivity moderately increased after hindlimb ischemia, and further increased at 4 h of reperfusion but obviously reduced at 24 h.. The activation of systemic and local neutrophils and inflammatory cytokines may play an important role in myocardial injury induced by hindlimb IR in rats.

Topics: Animals; Disease Models, Animal; Hindlimb; Ischemia; Male; Myocardium; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Tumor Necrosis Factor-alpha

Ischaemia/reperfusion injury is a common problem in hepatic surgery. An appreciation of the role of sevoflurane dose in preconditioning and subsequent hepatoprotection against ischaemia/reperfusion injury would be useful.. The aim of current study was to investigate the protective effect of sevoflurane preconditioning at different doses on hepatic ischaemia/reperfusion injury in rats.. Randomised, controlled, laboratory study.. The Department of Anaesthesiology, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, Guangdong, China.. Fifty male Sprague-Dawley rats weighing 200 to 250 g, randomly assigned to five groups.. Control group (sham surgery, no ischaemia/reperfusion), I/R group (ischaemia/reperfusion but no sevoflurane pretreatment), S1 [1 minimum alveolar concentration (MAC) = 2.4%], S2 (1.5 MAC = 3.6%) and S3 (2 MAC = 4.8%) groups with sevoflurane pretreatment, respectively, followed by 60 min ischaemia and 120 min reperfusion.. At the end of reperfusion, serum levels of alanine aminotransferase and aspartate aminotransferase as well as superoxide dismutase activity, myeloperoxidase and malondialdehyde content in the liver were determined. Histological examination of the liver was also performed.. Serum levels of aspartate aminotransferase and alanine aminotransferase in the sevoflurane groups were significantly reduced compared to the elevated levels seen in the I/R group (P < 0.05). In the liver, the I/R-induced increase in myeloperoxidase activity and malondialdehyde level were significantly reduced by all sevoflurane concentrations (P < 0.05). The decrease in superoxide dismutase activity induced by I/R was prevented by all sevoflurane pretreatments (P < 0.05). No significant differences between the S1, S2 and S3 groups were seen in any of the above variables.. Sevoflurane pretreatment exerts a protective effect on hepatic ischaemia/reperfusion injury but there is no significant dose-response relationship in the concentration range used. It is possible that a dose-response relationship might exist at lower concentrations.

Topics: Alanine Transaminase; Anesthetics, Inhalation; Animals; Aspartate Aminotransferases; Biomarkers; Cytoprotection; Disease Models, Animal; Dose-Response Relationship, Drug; Liver; Male; Malondialdehyde; Methyl Ethers; Peroxidase; Protective Factors; Rats, Sprague-Dawley; Reperfusion Injury; Sevoflurane; Superoxide Dismutase; Time Factors

To investigate the antioxidant and anti-inflammatory effects of Shengmai San (SMS) and its ethyl acetate extract (SEa), n-butanol extract (SBu), and aqueous extract (SWe), and clarify the material base of SMS and the roles played by its fractions.. A mouse model of transient forebrain ischemia/reperfusion (I/R) by means of common carotid artery occlusion (CCAO) was used to investigate the effects of SMS and its three fractions. Histopathological damage, blood-brain barrier disruption, and antioxidant and inflammation-related parameters, including malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), myeloperoxidase (MPO), nitric oxide (NO), tumor necrosis factor-α (TNF-α) were measured. The chemical constituents of each fraction were identified by LC-MS.. Eighteen lignans in SEa, and thirteen steroidal glycosides and ginsenosides in SBu were determined. SMS significantly inhibited I/R induced formation of histological injury and cerebral MPO activity. SMS showed the strongest antioxidant and anti-inflammatory effects against the I/R-caused injuries. SEa showed higher antioxidant activity than the other two fractions and SBu has a slightly stronger inhibition on the productions of NO and TNF-α.. SMS as a whole had the most effective protection against cerebral I/R-caused injuries compared with its fractions, which inferred that it contains different groups of compounds that contribute together to its protective effect.

Topics: Animals; Chromatography, High Pressure Liquid; Disease Models, Animal; Drugs, Chinese Herbal; Glutathione Peroxidase; Humans; Male; Malondialdehyde; Nitric Acid; Oxidative Stress; Peroxidase; Protective Agents; Rats; Reperfusion Injury; Superoxide Dismutase

Hepatic ischemia/reperfusion injury (IRI), an exogenous, antigen-independent, local inflammation response, occurs in multiple clinical settings, including liver transplantation, hepatic resection, trauma, and shock. The nervous system maintains extensive crosstalk with the immune system through neuropeptide and peptide hormone networks. This study examined the function and therapeutic potential of the vasoactive intestinal peptide (VIP) neuropeptide in a murine model of liver warm ischemia (90 minutes) followed by reperfusion. Liver ischemia/reperfusion (IR) triggered an induction of gene expression of intrinsic VIP; this peaked at 24 hours of reperfusion and coincided with a hepatic self-healing phase. Treatment with the VIP neuropeptide protected livers from IRI; this was evidenced by diminished serum alanine aminotransferase levels and well-preserved tissue architecture and was associated with elevated intracellular cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) signaling. The hepatocellular protection rendered by VIP was accompanied by diminished neutrophil/macrophage infiltration and activation, reduced hepatocyte necrosis/apoptosis, and increased hepatic interleukin-10 (IL-10) expression. Strikingly, PKA inhibition restored liver damage in otherwise IR-resistant VIP-treated mice. In vitro, VIP not only diminished macrophage tumor necrosis factor α/IL-6/IL-12 expression in a PKA-dependent manner but also prevented necrosis/apoptosis in primary mouse hepatocyte cultures. In conclusion, our findings document the importance of VIP neuropeptide-mediated cAMP-PKA signaling in hepatic homeostasis and cytoprotection in vivo. Because the enhancement of neural modulation differentially regulates local inflammation and prevents hepatocyte death, these results provide the rationale for novel approaches to managing liver IRI in transplant patients.

Topics: Animals; Apoptosis; Caspase 3; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Flow Cytometry; Hepatocytes; Homeostasis; Immune System; Inflammation; Interleukin-10; L-Lactate Dehydrogenase; Liver; Macrophages; Male; Mice; Mice, Inbred C57BL; Necrosis; Neutrophils; Peroxidase; Reperfusion Injury; Time Factors; Vasoactive Intestinal Peptide

Pentoxifylline, a methylxanthine derivative with significant hemorheologic properties, is used for claudication in patients with peripheral vascular disease, and experimentally for ischemic injury to organs because of its antioxidant and antiinflammatory effects. We used a rat model of severe small intestinal ischemia and reperfusion to determine the ability of pentoxifylline in improving survival, molecular response, and pathological protection.. We used 6 groups of male Wistar rats (n=25 each). The superior mesenteric artery was occluded for 120 minutes. Laboratory and tissue studies were done on 5 animals, 1 hour after reperfusion, and animal survival was assessed at 7 days. There were 2 control groups that received normal saline, either before ischemia or during reperfusion. The 4 treated groups received pentoxifylline 1 or 10 mg/kg at the same times mentioned above. Laboratory studies included measuring serum lactic acid dehydrogenase, tumor necrosis factor-α, interleukin-1β, and interleukin-6.Intestinal tissue malondialdehyde and myeloperoxidase in small intestine tissue also were measured. Histology and laser vascular blood flow at baseline and reperfusion were obtained, and survival was determined 7 days after ischemia.. A significant survival benefit in the animals treated with 10 mg/kg of pentoxifylline at reperfusion was noted. This coincided with a reduction in biochemical markers of cell damage - specifically, serum lactic acid dehydrogenase, and tissue malondialdehyde, ischemia, and reperfusion. Additionally, we saw decreased levels of tumor necrosis factor-α, interleukin-1β, and interleukin-6. Improved postreperfusion blood flow shown by laser Doppler technology also was seen in the treated groups. Histologically, we observed less neutrophil infiltration in the intestine of ischemic-treated rats. Also seen in the control animals were increased necrotic lesions in the microvilli with a higher presence of lysozyme in the Paneth cells. Survival was significantly better at 7 days (70% vs 40%) when we compared the pentoxifylline group treated at reperfusion (10 mg/kg) to the ischemic controls.. Pentoxifylline had a significant protective effect on severely ischemic bowel when administered during reperfusion at a dosage of 10 mg/kg. Better survival, improved histology, and molecular response should urge consideration of the consideration of applying these findings in some general surgery and transplant conditions.

Topics: Animals; Biomarkers; Blood Flow Velocity; Cytoprotection; Disease Models, Animal; Inflammation Mediators; Interleukin-1beta; Interleukin-6; Intestine, Small; L-Lactate Dehydrogenase; Laser-Doppler Flowmetry; Male; Malondialdehyde; Mesenteric Vascular Occlusion; Neutrophil Infiltration; Pentoxifylline; Peroxidase; Protective Agents; Rats; Rats, Wistar; Reperfusion Injury; Splanchnic Circulation; Time Factors; Tumor Necrosis Factor-alpha

To evaluate the therapeutic utility of hyperbaric oxygen (HBO) therapy on testicular ischemia/reperfusion (I/R) injury and elucidate the underlying molecular mechanism, we tested whether HBO therapy provided rescue of the testes after torsion in rats.. Sprague-Dawley rats were randomly divided into 4 groups: control group, control plus HBO therapy, I/R group, and I/R plus HBO therapy. The I/R model was induced by torsion of the right testis.. I/R in the testis resulted in disrupted seminiferous tubules, germ cell-specific apoptosis, followed by a marked reduction in testis weight and daily sperm production. HBO therapy preserved seminiferous tubules, suppressed apoptosis, and prevented testicular atrophy in I/R testes. HBO therapy abated oxidative stress in I/R testes, marked by reduced malondialdehyde formation, enhanced activities of superoxide dismutase and heme oxygenase 1 (HO-1), and decreased activities of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and xanthine oxidase. HBO therapy resulted in a reduction of myeloperoxidase (MPO) activity in I/R testes, a marker of neutrophil recruitment. HBO therapy suppressed inflammation in I/R testes, marked by reduced messenger RNA (mRNA) levels of tumor necrosis factor-α (TNF-α), interleukin-1beta (IL-1β), and CD44. Furthermore, HBO therapy suppressed the activation of nuclear factor kappa B (NFκB), p38, and c-JUN-N-terminal kinase (JNK) signaling pathways in I/R testes. In addition, HBO therapy reduced nitric oxide formation in I/R testes through suppression of inducible nitric oxide synthase and dimethylarginine dimethylaminohydrolase.. HBO therapy in rats attenuated I/R-induced testicular injury, possibly through abating oxidative stress, suppressing inflammation, and reducing nitric oxide formation.

Topics: Animals; Apoptosis; Heme Oxygenase-1; Hyaluronan Receptors; Hyperbaric Oxygenation; Inflammation; Interleukin-1beta; Male; Malondialdehyde; MAP Kinase Signaling System; NADPH Oxidases; NF-kappa B; Nitric Oxide; Oxidative Stress; Peroxidase; Rats; Reperfusion Injury; RNA, Messenger; Seminiferous Tubules; Spermatozoa; Superoxide Dismutase; Testicular Diseases; Testis; Torsion Abnormality; Tumor Necrosis Factor-alpha; Xanthine Oxidase

D-allose, a type of rare sugar, can produce inhibitory effects on activated leukocytes in various organs, including immunosuppressive effects and anti-inflammatory effects, as well as anti-oxyradical effects. The present experiment was performed to investigate the potential anti-inflammatory effects of D-allose in acute cerebral ischemia/reperfusion (I/R) injury. Transient middle cerebral artery occlusion model was applied in rats. D-allose was administered two times via a tail vein (300 mg/kg, 1 hour before ischemia and 10 hours after reperfusion). After 22 hours of reperfusion following 2 hours of ischemia, brain damage was evaluated by cerebral infarct volume. Myeloperoxidase (MPO) activity assay by enzyme-linked immunosorbent assay, and protein expression of MPO and cyclooxygenase-2 (COX-2) by immunohistochemistry were evaluated to investigate the potential mechanisms of D-allose. The experimental results showed that D-allose exhibited significant neuroprotective effects against acute cerebral I/R injury. The infarct volume in D-allose-treated rats (90.9 ± 13.5 mm(3)) was significantly smaller than that in vehicle rats (114.9 ± 15.3 mm(3), p < 0.01). D-allose treatment significantly suppressed the MPO activity and the number of MPO-positive cells compared with those in the vehicle group, suggesting that treatment with D-allose can reduce the infiltration of leukocytes into the ischemic tissue. Treatment of D-allose also significantly decreased the number of COX-2-positive cells and microglial activation in the ischemic tissue. The present results demonstrate that D-allose exerts potent neuroprotective effects against acute cerebral I/R injury, and constitute the first evidence of anti-inflammatory effects of D-allose which considerably contributes to the beneficial effects. Treatment with D-allose might provide a new strategy and clinically beneficial outcome for acute ischemic stroke.

Topics: Animals; Anti-Inflammatory Agents; Brain; Brain Ischemia; Cerebral Infarction; Cyclooxygenase 2; Enzyme-Linked Immunosorbent Assay; Glucose; Humans; Male; Peroxidase; Rats, Sprague-Dawley; Reperfusion Injury

Methotrexate was developed as a cytostatic agent, but at low doses, it has shown potent anti-inflammatory activity. Previous studies have demonstrated that the anti-inflammatory effects of methotrexate are primarily mediated by the release of adenosine. In this study, we hypothesized that low-dose methotrexate has protective effects in spinal cord ischemia-reperfusion injury. Rabbits were randomized into the following four groups of eight animals each: group 1 (control), group 2 (ischemia), group 3 (methylprednisolone) and group 4 (methotrexate). In the control group only a laparotomy was performed. In all the other groups, the spinal cord ischemia model was created by the occlusion of the aorta just caudal to the renal artery. Neurological evaluation was performed with the Tarlov scoring system. Levels of myeloperoxidase, malondialdehyde and catalase were analyzed, as were the activities of xanthine oxidase and caspase-3. Histopathological and ultrastructural evaluations were also performed. After ischemia-reperfusion injury, increases were found in the serum and tissue myeloperoxidase levels, tissue malondialdehyde levels, xanthine oxidase activity and caspase-3 activity. In contrast, both serum and tissue catalase levels were decreased. After the administration of a low-dose of methotrexate, decreases were observed in the serum and tissue myeloperoxidase levels, tissue malondialdehyde levels, xanthine oxidase activity and caspase-3 activity. In contrast, both the serum and tissue catalase levels were increased. Furthermore, low-dose methotrexate treatment showed improved results concerning the histopathological scores, the ultrastructural score and the Tarlov scores. Our results revealed that low-dose methotrexate exhibits meaningful neuroprotective activity following ischemia-reperfusion injury of the spinal cord.

Topics: Animals; Caspase 3; Catalase; Dose-Response Relationship, Drug; In Vitro Techniques; Male; Malondialdehyde; Methotrexate; Methylprednisolone; Peroxidase; Rabbits; Reperfusion Injury; Spinal Cord; Xanthine Oxidase

Stabilizing mast cells (MCs) can either inhibit or augment inflammation; however, how improved therapeutic benefits against small intestinal ischemia-reperfusion injury (IIRI) can be achieved by stabilizing MCs remains to be elucidated. The present study was designed to evaluate different treatments with cromolyn sodium (CS, an MC stabilizer), which was administrated either prior to ischemia or after reperfusion. Kunming mice were randomized into a sham-operated group (SH), a sole IIR group (M), in which mice were subjected to 30 min superior mesenteric artery occlusion followed by 3 day or 3 h reperfusion, or IIR, treated with CS 15 min prior to ischemia or 15 min after reperfusion in the PreCr and PostCr groups. The survival rate and Chiu's scores were evaluated. The levels of ET-1, histamine, TNF-α and IL-6, and expression of MC protease 7 (MCP7), MC counts and myeloperoxidase (MPO) activity were quantified. IIR resulted in severe injury as demonstrated by significant increases in mortality and injury score. IIR also led to substantial elevations in the levels of ET-1, histamine, TNF-α and IL-6, expression of MCP7, MC counts and MPO activities (P<0.05, M vs. SH groups). All biochemical changes were markedly reduced in the PostCr group (P<0.05, PostCr vs. M groups), whereas pretreatment of IIR mice with CS prior to ischemia exhibited no changes of ET-1 levels, injury score and inflammation (P>0.05, PreCr vs. M groups). In conclusion, administration of CS after reperfusion, but not prior to ischemia, attenuates IIRI by downregulating ET-1 and suppressing sustained MC activation.

Topics: Animals; Anti-Asthmatic Agents; Cromolyn Sodium; Down-Regulation; Endothelin-1; Histamine; Interleukin-6; Intestinal Mucosa; Ischemia; Male; Mast Cells; Mice; Peptide Hydrolases; Peroxidase; Reperfusion Injury; Severity of Illness Index; Survival Rate; Tumor Necrosis Factor-alpha

Intestinal ischemia/reperfusion (I/R) injury is a serious condition in intensive care patients, resulting in severe inflammation and remote organ damage. The activation of the mammalian target of rapamycin (mTOR)/p70 ribosomal S6 kinase (p70S6K) signaling pathway exerts protective effect against ischemia/reperfusion injury. Ghrelin, an orexigenic hormone, inhibits the release of pro-inflammatory cytokines, such as interleukin (IL)-1β, tumor necrosis factor-α and IL-6. In this study, we investigated the effects of ghrelin on gut I/R injury and the regulation of the mTOR/p70S6K signaling pathway following gut I/R injury in mice. C57BL/6 mice underwent superior mesenteric artery occlusion for 45 min, followed by reperfusion for 4 h. Ghrelin was administered at the onset of reperfusion. We assessed survival, organ injury variables, pro-inflammatory cytokine expression and observed the histological changes of the small intestine and lungs. Our results revealed that the administration of ghrelin inhibited the release of certain pro-inflammatory cytokines, reduced neutrophil infiltration, attenuated organ injury and improved survival following gut I/R injury. The administration of D-Lys-GHRP6, a specific ghrelin receptor antagonist, to a certain extent, counteracted the protective effects of ghrelin in gut I/R-induced organ injury and mortality. To determine whether the beneficial effects of ghrelin following gut I/R injury are associated with the mTOR/p70S6K signaling pathway, the phosphorylation levels of mTOR and p70S6K were detected by western blot analysis. Our results revealed that mTOR and p70S6K phosphorylation increased in the tissue from the small intestine and pulmonary tissue in the animals treated with ghrelin. These findings suggest that ghrelin attenuates organ injury following gut I/R by promoting the activation of the mTOR/p70S6K signaling pathway.

Topics: Animals; Ghrelin; Inflammation; Interleukin-1beta; Interleukin-6; Intestines; Lung; Male; Mice; Mice, Inbred C57BL; Neutrophil Infiltration; Peroxidase; Phosphorylation; Reperfusion Injury; Ribosomal Protein S6 Kinases, 70-kDa; Signal Transduction; TOR Serine-Threonine Kinases; Tumor Necrosis Factor-alpha

An araban type polysaccharide (GBPw) was purified from the leaves of Ginkgo biloba. The present study aimed to investigate the protective effects of GBPw on focal ischemia/reperfusion (I/R) injury in rat brain. The results of this study demonstrated that GBPw had a positive effect on the rat brain when administered 7 days before focal cerebral I/R injury. This effect was evident with the improvements in neurological deficits, reduction in infarct volume, MDA content and the levels of pro-inflammatory cytokines (TNF-α and IL-1β), and elevation in the SOD and MPO activities and the levels of anti-inflammatory cytokine (IL-10). Thus, the beneficial effects of GBPw on cerebral I/R injury may result from the reduction of oxidative stress and the inhibition of NO production and inflammation induced by I/R. The neuroprotective effects of GBPw supplement may have potential implication in the future for prevention/protection against cerebral ischemic stroke.

Topics: Animals; Brain; Brain Chemistry; Brain Ischemia; Ginkgo biloba; Interleukin-10; Interleukin-1beta; Male; Malondialdehyde; Neuroprotective Agents; Nitric Oxide; Oxidative Stress; Peroxidase; Plant Leaves; Polysaccharides; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase; Tumor Necrosis Factor-alpha

Polyunsaturated fatty acid (PUFA) metabolites are bioactive autoacoids that play an important role in the pathogenesis of a vast number of pathologies, including gut diseases. The induction and the resolution of inflammation depend on PUFA metabolic pathways that are favored. Therefore, understanding the profile of n-6 (eicosanoids)/n-3 (docosanoids) PUFA-derived metabolites appear to be as important as gene or protein array approaches, to uncover the molecules potentially implicated in inflammatory diseases. Using high sensitivity liquid chromatography tandem mass spectrometry, we characterized the tissue profile of PUFA metabolites in an experimental model of murine intestinal ischemia reperfusion. We identified temporal and quantitative differences in PUFA metabolite production, which correlated with inflammatory damage. Analysis revealed that early ischemia induces both pro-inflammatory and anti-inflammatory eicosanoid production. Primarily, LOX- (5/15/12/8-HETE, LTB4, LxA4) and CYP- (5, 6-EET) metabolites were produced upon ischemia, but also PGE3, and PDx. This suggests that different lipids simultaneously play a role in the induction and counterbalance of ischemic inflammatory response from its onset. COX-derived metabolites were more present from 2 to 5 hours after reperfusion, fitting with the concomitant inflammatory peaks. All metabolites were decreased 48 hours post-reperfusion except for to the pro-resolving RvE precursor 18-HEPE and the PPAR-γαμμα agonist, 15d-PGJ2. Data obtained through the pharmacological blockade of transient receptor potential vanilloid-4, which can be activated by 5, 6-EET, revealed that the endogenous activation of this receptor modulates post-ischemic intestinal inflammation. Altogether, these results demonstrate that different lipid pathways are involved in intestinal ischemia-reperfusion processes. Some metabolites, which expression is severely changed upon intestinal ischemia-reperfusion could provide novel targets and may facilitate the development of new pharmacological treatments.

Topics: Animals; Chromatography, Liquid; Cytokines; Fatty Acids, Unsaturated; Inflammation; Inflammation Mediators; Intestine, Small; Ischemia; Male; Mice; Mice, Inbred C57BL; Peroxidase; Reperfusion Injury; Survival Rate; Tandem Mass Spectrometry

Ischemia-reperfusion injury (IRI) remains a major problem in renal transplantation, and the inflammatory response to IRI exacerbates the resultant renal injury. We have investigated whether the systemic administration of cardiotrophin-1 (CT-1) is able to improve renal function and to decrease inflammatory responses in a rat model of renal IRI.. IRI was induced by renal pedicle clamping (60 min) followed by reperfusion and contralateral nephrectomy. CT-1 was injected through the penile vein 30 min before clamping release and its effects were compared with a saline-treated group at five different time points of reperfusion.. Survival in the CT-1-treated group was higher than in the untreated group and prevented IRI-induced reduction in the glomerular filtration rate, as shown by blunted increases in creatinine and urea plasma levels and less severe decrease in creatinine clearance. These effects of CT-1 seem to be mediated by reduction in oxygen-radical production, increased superoxide dismutase expression, attenuation of neutrophil and macrophage infiltration, lower adhesion molecule expression, lower inflammation demonstrated by a decrease of plasma levels of proinflammatory cytokine secretion such as tumor necrosis factor-α, interleukin-1β and interferon-γ, lower inducible nitric oxide synthase expression and lower nuclear factor-κB activation, and reduced apoptosis.. Therefore, these results suggest that CT-1 administration prevents IRI and it might be used as a therapeutic strategy to protect the kidney against IRI.

Topics: Animals; Apoptosis; Cytokines; Inflammation; Interferon-gamma; Interleukin-1beta; Kidney; Kidney Transplantation; Macrophages; Male; Neutrophils; NF-kappa B; Nitric Oxide Synthase Type II; Peroxidase; Rats; Rats, Wistar; Reactive Oxygen Species; Reperfusion Injury; Superoxide Dismutase; Superoxides; Time Factors; Tumor Necrosis Factor-alpha

Early allograft dysfunction following lung transplantation is mainly an ischemia/reperfusion (IR) injury. We showed that relaxin-2 (relaxin) exerts a protective effect in lung IR, attributable to decreases in endothelin-1 (ET-1) production, leukocyte recruitment, and free radical generation. Here, we summarize our investigations into relaxin's signalling.. Isolated rat lungs were perfused with vehicle or 5 nM relaxin (n = 6-10 each). Thereafter, experiments were conducted in the presence of relaxin plus vehicle, the protein kinase A inhibitors H-89 and KT-5720, the NO synthase (NOS) inhibitor L-NAME, the iNOS inhibitor 1400W, the nNOS inhibitor SMTC, the extracellular signal-regulated kinase-1/2 (ERK-1/2) inhibitor PD-98059, the phosphatidylinositol-3 kinase (PI3K) inhibitor wortmannin, the endothelin type-B (ETB) antagonist A-192621, or the glucocorticoid receptor (GR) antagonist RU-486. After 90 min ischemia and 90 min reperfusion we determined wet-to-dry (W/D) weight ratio, mean pulmonary arterial pressure (MPAP), vascular release of ET-1, neutrophil elastase (NE), myeloperoxidase (MPO), and malondialdehyde (MDA). Primary rat pulmonary vascular cells were similarly treated.. IR lungs displayed significantly elevated W/D ratios, MPAP, as well as ET-1, NE, MDA, and MPO. In the presence of relaxin, all of these parameters were markedly improved. This protective effect was completely abolished by L-NAME, 1400W, PD-98059, and wortmannin whereas neither PKA and nNOS inhibition nor ETB and GR antagonism were effective. Analysis of NOS gene expression and activity revealed that the relaxin-induced early and moderate iNOS stimulation is ERK-1/2-dependent and counter-balanced by PI3K. Relaxin-PI3K-related phosphorylation of a forkhead transcription factor, FKHRL1, paralleled this regulation. In pulmonary endothelial and smooth muscle cells, FKHRL1 was essential to relaxin-PI3K signalling towards iNOS.. In this short-time experimental setting, relaxin protects against IR-induced lung injury via early and moderate iNOS induction, dependent on balanced ERK-1/2 and PI3K-FKHRL1 stimulation. These findings render relaxin a candidate drug for lung preservation.

Topics: Animals; Blood Pressure; Forkhead Box Protein O3; Forkhead Transcription Factors; Gene Expression Regulation; Leukocyte Elastase; Lung; Malondialdehyde; MAP Kinase Signaling System; Nitric Oxide Synthase; Peroxidase; Phosphatidylinositol 3-Kinases; Pulmonary Artery; Rats; Relaxin; Reperfusion Injury; Vascular Resistance

Ischemia-reperfusion lung injury is a common cause of acute morbidity and mortality in lung transplant recipients and has been associated with subsequent development of bronchiolitis obliterans syndrome. Recognition of endogenous ligands released during cellular injury (damage-associated molecular patterns; DAMPs) by Toll-like receptors (TLRs), especially TLR4, has increasingly been recognized as a mechanism for inflammation resulting from tissue damage. TLR4 is implicated in the pathogenesis of ischemia-reperfusion injury of multiple organs including heart, liver, kidney and lung. Additionally, activation of TLRs other than TLR4 by DAMPs has been identified in tissues other than the lung. Because all known TLRs, with the exception of TLR3, signal via the MyD88 adapter protein, we hypothesized that lung ischemia-reperfusion injury was mediated by MyD88-dependent signaling. To test this hypothesis, we subjected C57BL/6 wildtype, Myd88(-/-), and Tlr4(-/-) mice to 1 hr of left lung warm ischemia followed by 4 hr of reperfusion. We found that Myd88(-/-) mice had significantly less MCP-1/CCL2 in the left lung following ischemia-reperfusion as compared with wildtype mice. This difference was associated with dramatically reduced lung permeability. Interestingly, Tlr4(-/-) mice had only partial protection from ischemia-reperfusion as compared to Myd88(-/-) mice, implicating other MyD88-dependent pathways in lung injury following ischemia-reperfusion. We also found that left lung ischemia-reperfusion caused remote inflammation in the right lung. Finally, using chimeric mice with MyD88 expression restricted to either myeloid or non-myeloid cells, we found that MyD88-dependent signaling in myeloid cells was necessary for ischemia-reperfusion induced lung permeability. We conclude that MyD88-dependent signaling through multiple receptors is important in the pathogenesis of acute lung inflammation and injury following ischemia and reperfusion.

Topics: Acute Lung Injury; Animals; Chemokine CCL2; Cytokines; Disease Models, Animal; HEK293 Cells; Humans; Ligands; Lung; Mice; Mice, Knockout; Myeloid Cells; Myeloid Differentiation Factor 88; Permeability; Peroxidase; Pulmonary Alveoli; Reperfusion Injury; Time Factors; Toll-Like Receptor 4

Acute intestinal ischaemia/reperfusion injury (AII/R) is an adaptive physiologic response during critical illness, involving mesenteric vasoconstriction and hypoperfusion. Prevention of AII/R in high risk patient populations would have a significant impact on morbidity and mortality. The purpose of this study was to investigate the protective effects of VSL#3 probiotic treatment in a murine model of AII/R. Adult 129/SvEv mice were subjected to an experimental AII/R model using superior mesenteric artery occlusion. Animals were pre-treated with either three days or two weeks of VSL#3 probiotics. Local tissue injury markers were assessed by levels of myeloperoxidase and activation of nuclear factor kappa B (NFкB). Systemic and local cytokines, including interleukin (IL)-1β, IL- 10, TNFα, and interferon gamma were measured by ELISA and multiplex fluorescent detection. VSL#3 probiotics reduced local tissue inflammation and injury due to AII/R. A two-week course of VSL#3 was more effective than a shorter three-day course. The reduction in local inflammation from the two-week course of VSL#3 is correlated to a significant reduction in levels of active IL-1β, and tissue levels of myeloperoxidase. Levels of active NFкB were significantly elevated in the vehicle-fed AII/R mice, corroborating with tissue inflammation, which were attenuated by VSL#3 administrations. VSL#3 did not cause any systemic inflammation or lung injury. VSL#3 probiotics are effective in reducing local tissue injury from AII/R by down-regulating pro-inflammatory mediators and immune cell recruitment. This study highlights a potential role for VSL#3 in management of patients at high risk for AII/R.

Topics: Animals; Cytokines; Disease Models, Animal; Intestinal Diseases; Ischemia; Mice; NF-kappa B; Peroxidase; Probiotics; Reperfusion Injury; Treatment Outcome

The study aimed to investigate whether sevoflurane preconditioning can protect against small intestinal ischemia reperfusion (IIR) injury and to explore whether mast cell (MC) is involved in the protections provided by sevoflurane preconditioning. Sprague-Dawley rats exposed to sevoflurane or treated with MC stabilizer cromolyn sodium (CS) were subjected to 75-minute superior mesenteric artery occlusion followed by 2-hour reperfusion in the presence or absence of MC degranulator compound 48/80 (CP). Small intestinal ischemia reperfusion resulted in severe intestinal injury as demonstrated by significant elevations in intestinal injury scores and p47(phox) and gp91(phox), ICAM-1 protein expressions and malondialdehyde and IL-6 contents, and MPO activities as well as significant reductions in SOD activities, accompanied with concomitant increases in mast cell degranulation evidenced by significant increases in MC counts, tryptase expression, and β-hexosaminidase concentrations, and those alterations were further upregulated in the presence of CP. Sevoflurane preconditioning dramatically attenuated the previous IIR-induced alterations except MC counts, tryptase, and β-hexosaminidase which were significantly reduced by CS treatment. Furthermore, CP exacerbated IIR injury was abrogated by CS but not by sevoflurane preconditioning. The data collectively indicate that sevoflurane preconditioning confers protections against IIR injury, and MC is not involved in the protective process.

Topics: Anesthetics, Inhalation; Animals; beta-N-Acetylhexosaminidases; Cromolyn Sodium; Female; Immunoenzyme Techniques; Intercellular Adhesion Molecule-1; Interleukin-6; Intestinal Mucosa; Intestine, Small; Malondialdehyde; Mast Cells; Membrane Glycoproteins; Mesenteric Artery, Superior; Methyl Ethers; NADPH Oxidase 2; NADPH Oxidases; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sevoflurane; Tryptases

The objective of the present study was to evaluate the protective effects of halofuginone against renal ischemia/reperfusion (I/R) injury.. Male Wistar albino rats were unilaterally nephrectomized and the left renal pedicles were occluded for 45 min to induce ischemia and then reperfused for 6 h (early) or for 72 h (late). The rats were treated intraperitoneally with either halofuginone (100 μg/kg/day) or saline 30 min prior to ischemia and the dose was repeated in the late reperfusion groups. In the sham groups, rats underwent unilateral nephrectomy and were treated at similar time points. The animals were decapitated at either 6 h or 72 h of reperfusion and trunk blood and kidney samples were obtained.. I/R injury increased renal malondialdehyde levels, myeloperoxidase activity and reactive oxygen radical levels, and decreased the renal glutathione content. Halofuginone treatment was found to reduce oxidative I/R injury and improve renal function in the rat kidney, as evidenced by reduced generation of reactive oxygen species, depressed lipid peroxidation and myeloperoxidase activity, and increased glutathione levels.. The present findings demonstrate the anti-inflammatory and antioxidant effects of halofuginone in renal I/R injury, supporting its potential use where renal I/R injury is inevitable.

Topics: Animals; Blood Urea Nitrogen; Creatinine; Disease Models, Animal; Fibrosis; Glutathione; Kidney Diseases; L-Lactate Dehydrogenase; Lipid Peroxidation; Male; Nephrectomy; Oxidative Stress; Peroxidase; Piperidines; Protein Synthesis Inhibitors; Quinazolinones; Rats; Rats, Wistar; Reperfusion Injury

Tissue protection against ischemia (I)/reperfusion (R) injury by heparins can be due to their anticoagulant and/or non-anticoagulant properties. Here we studied the protective potential of the anticoagulant and the non-anticoagulant features of heparin sodium (HepSo) and enoxaparin (Enox) against mesenteric I/R injury in a rat model.. Mesenteric I/R was induced in rats (n = 6 per group) by superior mesenteric artery occlusion (SMAO; 90 min) and reopening (120 min). Therapeutic/clinical and subtherapeutic/non-anticoagulant doses of HepSo (0.25 mg/kg bolus + 0.25 mg/kg × h; 0.05 mg/kg bolus + 0.1 mg/kg × h) or Enox (0.5 mg/kg bolus + 0.5 mg/kg × h; 0.05 mg/kg bolus + 0.1 mg/kg × h) were administered intravenously starting 30 min before SMAO to the end of reperfusion. Systemic/vital and intestinal microcirculatory parameters were measured during the whole experimental procedure, those of small intestine injury at the end.. During intestinal reperfusion, mean arterial blood pressure and heart rates were significantly increased by HepSo and, less effectively, by Enox, in a dose-dependent manner. Intestinal microcirculation was only affected by the therapeutic HepSo dose, which decreased the microvascular flow and S(O2) during reperfusion. The subtherapeutic Enox treatment, as opposed to any HepSo dose, most effectively diminished I/R-induced intestinal hemorrhages, myeloperoxidase activity (as a measure of neutrophil invasion), and histopathological changes.. Therapeutic but, to a lesser extent, also the subtherapeutic doses of both HepSo and Enox clearly improve hemodynamics during mesenteric reperfusion, while intestinal protection is exclusively provided by Enox, especially at its subtherapeutic dose. Alterations in intestinal microcirculation are not responsible for these effects. Thus, non-anticoagulant Enox doses and, preferably, heparin(oid)s unable to affect coagulation, could diminish clinical risks of I/R-induced gastrointestinal complications.

Topics: Animals; Anticoagulants; Blood Pressure; Dose-Response Relationship, Drug; Enoxaparin; Heart Rate; Hemodynamics; Heparin; Intestine, Small; Male; Mesentery; Microcirculation; Models, Animal; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Inflammatory response plays a pathogenic role in liver ischemia/reperfusion (I/R) injury. All-trans retinoic acid (ATRA) is an active metabolite of vitamin A with anti-inflammatory effects. However, there are few reports on the anti-inflammatory effects of ATRA on liver I/R injury. The purpose of this study was to investigate the effects of ATRA on liver I/R injury and related mechanisms.. A total of 54 male Sprague-Dawley rats were randomly divided into three groups (18 rats each), namely, sham, I/R, and I/R+ATRA groups. ATRA was intraperitoneally administered at a dose of 15mg/kg/d 14d before ischemia surgery. The segmental (70%) hepatic ischemia model was used by clamping the portal vein, hepatic artery, and bile duct of the left and median for 1h. The rats were sacrificed 3, 6, and 24h after reperfusion, and blood and liver tissue samples were obtained. Liver injury was evaluated by biochemical and histopathologic examinations. Myeloperoxidase activity was spectrophotometrically measured. The expression of pro-inflammatory cytokines, such as tumor necrosis factor-α and interleukin-6 was measured by enzyme-linked immunosorbent assay and real-time polymerase chain reaction. Liver nuclear factor kappa B (NF-κB) was detected by immunohistochemistry. The expression of NF-κB p65 and inhibitor NF-κB-α (IκBα) was determined by Western blot analysis.. The serum alanine aminotransferase level, Suzuki scores of hepatic histology, and hepatic myeloperoxidase activity, as indices of hepatic injury, were increased after reperfusion. The increase was attenuated by preadministration with ATRA. Compared with the I/R group, ATRA treatment increased IκBα expression and suppressed NF-κB p65 expression. Subsequently, the levels of tumor necrosis factor-α and interleukin-6 after liver I/R were effectively downregulated.. ATRA administration can significantly attenuate I/R injury in rat liver. The protective mechanism is related to its anti-inflammatory function of inhibiting NF-κB activation.

Topics: Animals; Interleukin-6; Ischemic Preconditioning; Liver; Male; NF-kappa B; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Signal Transduction; Tretinoin; Tumor Necrosis Factor-alpha

Intestinal ischemia and reperfusion (i-I/R) is an insult associated with acute respiratory distress syndrome (ARDS). It is not known if pro- and anti-inflammatory mediators in ARDS induced by i-I/R can be controlled by low-level laser therapy (LLLT). This study was designed to evaluate the effect of LLLT on tracheal cholinergic reactivity dysfunction and the release of inflammatory mediators from the lung after i-I/R. Anesthetized rats were subjected to superior mesenteric artery occlusion (45 min) and killed after clamp release and preestablished periods of intestinal reperfusion (30 min, 2 or 4 h). The LLLT (660 nm, 7.5 J/cm(2)) was carried out by irradiating the rats on the skin over the right upper bronchus for 15 and 30 min after initiating reperfusion and then euthanizing them 30 min, 2, or 4 h later. Lung edema was measured by the Evans blue extravasation technique, and pulmonary neutrophils were determined by myeloperoxidase (MPO) activity. Pulmonary tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10), intercellular adhesion molecule-1 (ICAM-1), and isoform of NO synthase (iNOS) mRNA expression were analyzed by real-time PCR. TNF-α, IL-10, and iNOS proteins in the lung were measured by the enzyme-linked immunoassay technique. LLLT (660 nm, 7.5 J/cm(2)) restored the tracheal hyperresponsiveness and hyporesponsiveness in all the periods after intestinal reperfusion. Although LLLT reduced edema and MPO activity, it did not do so in all the postreperfusion periods. It was also observed with the ICAM-1 expression. In addition to reducing both TNF-α and iNOS, LLLT increased IL-10 in the lungs of animals subjected to i-I/R. The results indicate that LLLT can control the lung's inflammatory response and the airway reactivity dysfunction by simultaneously reducing both TNF-α and iNOS.

Topics: Animals; Gene Expression Regulation; Inflammation Mediators; Intercellular Adhesion Molecule-1; Interleukin-10; Intestines; Low-Level Light Therapy; Male; Nitric Oxide Synthase Type II; Peroxidase; Pneumonia; Pulmonary Edema; Rats; Rats, Wistar; Reperfusion; Reperfusion Injury; Trachea; Tumor Necrosis Factor-alpha

The present study investigated the protective effects of a novel NHE1 selective inhibitor, sabiporide, in a porcine model of asphyxia-induced cardiac arrest. Asphyxial cardiac arrest was induced by endotracheal tube clamping (ETC). The animals remained untreated for 3 min after loss of aortic pulsations (LOAP), and followed by chest compression and defibrillation. Sixteen of eighteen pigs had return of spontaneous circulation (ROSC), and were randomly assigned to two study groups. Group 1: vehicle control. Group 2: 3mg/kg sabiporide was given at 15 min after ROSC. Post-arrest myocardial dysfunction was present in both groups, and progressed over hours. Animals treated with sabiporide had less wall motion abnormality and higher left ventricular ejection fraction than control animals (33% in control group vs. 47% in sabiporide group). Sabopiride treatment also significantly improved post-arrest arterial blood pressure by 25% and cardiac stroke volume by 44%, and improved mixed-venous blood oxygen saturation by 38% and oxygen delivery by 118%. Furthermore, compared to the control group, the sabiporide group also had higher blood flows in the brain, heart, kidney, liver and spleen at 30 min after ROSC. There was no significant blood flow difference in distal ileum mucosa between control and sabiporide groups. In addition, sabiporide treatment significantly reduced cardiac myeloperoxidase (MPO) activity by 53% and cardiac troponin I by 51%, and reduced the plasma level of TNF-α by 52% and IL-6 by 41%. This study shows that post-arrest pharmacological conditioning with sabiporide affords protection from whole body ischemia-reperfusion injury in this model of asphyxia-induced cardiac arrest and resuscitation.

Topics: Animals; Asphyxia; Blood Circulation; Blood Pressure; Cardiotonic Agents; Cation Transport Proteins; Guanidines; Heart Arrest, Induced; Interleukin-6; Models, Animal; Myocardial Stunning; Myocardium; Oxygen; Oxygen Consumption; Peroxidase; Reperfusion Injury; Sodium-Hydrogen Exchanger 1; Sodium-Hydrogen Exchangers; Stroke Volume; Swine; Troponin I; Tumor Necrosis Factor-alpha

Xanthine oxidase has been implicated in the pathogenesis of a wide spectrum of diseases, and is thought to be the most important source of oxygen-free radicals and cell damage during re-oxygenation of hypoxic tissues.. The present study was undertaken to demonstrate whether febuxostat is superior to allopurinol in prevention of the local and remote harmful effects of small intestinal ischemia/reperfusion injury in rats.. Intestinal ischemia was induced by superior mesenteric artery ligation. The rats were assigned to five groups: the sham control; the intestinal ischemia/reperfusion; the allopurinol; and the febuxostat 5 and 10 mg/kg pretreated ischemia/reperfusion groups. Treatment was administered from 7 days before ischemia induction. After the reperfusion, the serum and tissues were obtained for biochemical, pharmacological, and histological studies.. Intestinal reperfusion led to an elevation in the serum levels of alanine aminotransferase, aspartate aminotransferase, tumor necrosis factor-α, malondialdehyde, and xanthine oxidase as well as intestinal myeloperoxidase, malonadialdehyde, and xanthine oxidase/xanthine dehydrogenase activity. Furthermore, the ischemia/reperfusion induced a reduction in the contractile responsiveness to acetylcholine. These changes were significantly regulated by the pretreatment with febuxostat compared to allopurinol. The degree of pathological impairment in the intestinal mucosa, liver, and lung tissues were lighter in the pretreated groups.. Febuxostat may offer advantages over allopurinol in lessening local intestinal injury as well as remote hepatic and lung injuries induced by small intestinal ischemia/reperfusion.

Topics: Alanine Transaminase; Allopurinol; Animals; Aspartate Aminotransferases; Dose-Response Relationship, Drug; Febuxostat; Gout Suppressants; Intestinal Mucosa; Lipid Peroxidation; Lung; Male; Malondialdehyde; Muscle Contraction; Muscle, Smooth; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Thiazoles; Tumor Necrosis Factor-alpha; Xanthine Dehydrogenase; Xanthine Oxidase

The aim of this study was to analyze the effects of cryotherapy on the biochemical and morphological changes in ischemic and reperfused (I/R) gastrocnemius muscle of rats. Forty male Wistar rats were divided into control and I/R groups, and divided based on whether or not the rats were submitted to cryotherapy. Following the reperfusion period, biochemical and morphological analyses were performed. Following cryotherapy, a reduction in thiobarbituric acid-reactive substances and dichlorofluorescein oxidation levels were observed in I/R muscle. Cryotherapy in I/R muscle also minimized effects such as decreased cellular viability, levels of non-protein thiols and calcium ATPase activity as well as increased catalase activity. Cryotherapy also limited mitochondrial dysfunction and decreased the presence of neutrophils in I/R muscle, an effect that was corroborated by reduced myeloperoxidase activity in I/R muscle treated with cryotherapy. The effects of cryotherapy are associated with a reduction in the intensity of the inflammatory response and also with a decrease in mitochondrial dysfunction.

Topics: Analysis of Variance; Animals; Biomarkers; Cell Survival; Cryotherapy; Disease Models, Animal; Ischemia; Male; Mitochondria, Muscle; Muscle, Skeletal; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Intestinal ischemia-reperfusion (I/R) is a critical event in the pathogenesis of multiple organ dysfunction syndromes (MODS). The lungs are some of the most vulnerable organs that are impacted by intestinal I/R. The aim of this study is to investigate whether ginsenoside Rb1 can ameliorate remote lung injury induced by intestinal I/R. Adult male Wistar rats were randomly divided into four groups: (1) a control, sham-operated group (sham group); (2) an intestinal I/R group subjected to 1 h intestinal ischemia and 2 h reperfusion (I/R group); (3) a group treated with 20 mg/kg ginsenoside Rb1 before reperfusion (Rb1-20 group); and (4) a group treated with 40 mg/kg ginsenoside Rb1 before reperfusion (Rb1-40 group). Intestinal and lung histology was observed. The malondialdehyde (MDA) levels in intestinal tissues were measured. Myeloperoxidase (MPO), TNF-α, MDA levels, wet/dry weight ratio and immunohistochemical expression of intracellular adhesion molecule-1 (ICAM-1) in lung tissues were assayed. In addition, a western blot of lung NF-kB was performed. Results indicated that intestinal I/R induced intestinal and lung injury, which was characterized by increase of MDA levels and pathological scores in intestinal tissues and MPO, TNF-α , MDA levels, wet/dry weight ratio and ICAM-1, NF-kB expression in the lung tissues. Ginsenoside Rb1 (20, 40 mg/kg) ameliorated intestinal and lung injury, decreased MPO, TNF-α, MDA levels, wet/dry weight ratio, ICAM-1 and NF-kB expression in lung tissues. In conclusion, ginsenoside Rb1 ameliorated the lung injuries by decreasing the NF-kB activation-induced inflammatory response.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Ginsenosides; Intercellular Adhesion Molecule-1; Intestinal Mucosa; Intestine, Small; Lung; Lung Injury; Male; Malondialdehyde; Mesenteric Arteries; Mesenteric Vascular Occlusion; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Transcription Factor RelA; Tumor Necrosis Factor-alpha

The main objective of the study was to determine the neuroprotective effect of allopurinol and nimesulide against the cerebral ischemic reperfusion injury in diabetic and nondiabetic rats.. In this study, Wistar albino rats of either sex weighing 150-250 g were procured from authorized suppliers. Rats were anesthetized by giving thiopentone sodium (45 mg/kg) by i.p. Under anesthesia, midline incision was given. Common carotid arteries were identified and isolated carefully from vago-sympathetic nerve. Rats were made ischemic by occluding bicommon carotid arteries with thread for 30 min, followed by reperfusion for 4 h by removing the occlusion. The drugs allopurinol (15, 30 mg/kg) and nimesulide (20, 40 mg/kg) were administered 10 min before reperfusion. Then after 4 h reperfusion, animals were sacrificed and immediately brain was removed, homogenized, centrifuged and supernatant was collected, various enzyme estimations were done and same procedure was followed in streptozotocin (STZ: 45 mg/kg; i.p.) induced diabetic rats.. Ischemia reperfusion (I/R) group showed significant increase in malondialdehyde (MDA), myeloperoxidase (MPO) and depletion in catalase (CAT) and superoxide dismutase (SOD) levels. Treatment with allopurinol and nimesulide significantly decreased the MDA and MPO levels whereas increased the SOD and CAT levels when compared I/R group in both non-diabetic and diabetic rats.. These findings suggest the cerebral injury due to over production of free radicals was inhibited by allopurinol and nimesulide that exert a neuroprotective effect probably by radical scavenging and antioxidant activities.

Topics: Allopurinol; Animals; Brain Ischemia; Catalase; Diabetes Mellitus, Experimental; Female; Male; Neuroprotective Agents; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Streptozocin; Sulfonamides; Superoxide Dismutase

Ischemia-reperfusion injury contributes significantly to morbidity and mortality in lung transplant patients. Currently, no therapeutic agents are clinically available to prevent ischemia-reperfusion injury, and treatment strategies are limited to maintaining oxygenation and lung function. Adenosine can modulate inflammatory activity and injury by binding to various adenosine receptors; however, the role of the adenosine A1 receptor in ischemia-reperfusion injury and inflammation is not well understood. The present study tested the hypothesis that selective, exogenous activation of the A1 receptor would be anti-inflammatory and attenuate lung ischemia-reperfusion injury.. Wild-type and A1 receptor knockout mice underwent 1 hour of left lung ischemia and 2 hours of reperfusion using an in vivo hilar clamp model. An A1 receptor agonist, 2-chloro-N6-cyclopentyladenosine, was administered 5 minutes before ischemia. After reperfusion, lung function was evaluated by measuring airway resistance, pulmonary compliance, and pulmonary artery pressure. The wet/dry weight ratio was used to assess edema. The myeloperoxidase and cytokine levels in bronchoalveolar lavage fluid were measured to determine the presence of neutrophil infiltration and inflammation.. In the wild-type mice, 2-chloro-N6-cyclopentyladenosine significantly improved lung function and attenuated edema, cytokine expression, and myeloperoxidase levels compared with the vehicle-treated mice after ischemia-reperfusion. The incidence of lung ischemia-reperfusion injury was similar in the A1 receptor knockout and wild-type mice; and 2-chloro-N6-cyclopentyladenosine had no effects in the A1 receptor knockout mice. In vitro treatment of neutrophils with 2-chloro-N6-cyclopentyladenosine significantly reduced chemotaxis.. Exogenous A1 receptor activation improves lung function and decreases inflammation, edema, and neutrophil chemotaxis after ischemia and reperfusion. These results suggest a potential therapeutic application for A1 receptor agonists for the prevention of lung ischemia-reperfusion injury after transplantation.

Topics: Adenosine; Analysis of Variance; Animals; Bronchoalveolar Lavage Fluid; Chemotaxis; Cytokines; Disease Models, Animal; Lung Transplantation; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophil Infiltration; Peroxidase; Random Allocation; Receptor, Adenosine A1; Reperfusion Injury; Respiratory Function Tests

Capsaicin, a transient receptor potential vanilloid type 1 (TRPV1) agonist, was found to protect against myocardial and renal ischemia-reperfusion (IR) injury. This study was carried out to investigate the role of capsaicin in lung IR injury in vivo.. Forty male New Zealand rabbits were randomized into four groups (10 per group) as follows: sham group (sham thoracotomy), IR group (occlusion of the left pulmonary hilus for 1 h followed by reperfusion for 3 h), CAP (capsaicin) group (a bolus injection of CAP 5 min before ischemia), CPZ (capsazepine) group (a bolus injection of the TRPV1 antagonist CPZ 5 min before ischemia). Blood and lung tissue samples were obtained for blood gas and biochemical analyses, wet/dry weight ratio measurements, and histologic evaluation. Protein levels and neutrophils in the bronchoalveolar lavage fluid (BALF) were also measured.. Pretreatment with capsaicin improved gas exchange function, decreased lung wet/dry ratio and protein levels and neutrophil counts in BALF, decreased lung malondialdehyde levels and myeloperoxidase activities, increased superoxide dismutase activities, along with an elevation of calcitonin gene-related peptide (CGRP) level (P < 0.05 versus IR group). Capsaicin also attenuated IR-induced pathological lesions. By contrast, capsazepine exacerbated gas exchange abnormality, increased pulmonary microvascular permeability, oxidative stress, neutrophils infiltration, and also revealed a decreased CGRP level (P < 0.05 versus IR group).. Results from the present study show that capsaicin confers protection against lung IR injury. These protective effects seem to be closely related to the inhibition of inflammation and oxidative stress via the activation of TRPV1 and the release of CGRP.

Topics: Animals; Blood Gas Analysis; Bronchoalveolar Lavage Fluid; Calcitonin Gene-Related Peptide; Capsaicin; Lung; Male; Malondialdehyde; Models, Animal; Neutrophils; Oxidative Stress; Peroxidase; Rabbits; Reperfusion Injury; TRPV Cation Channels

Successful resuscitation after cardiac arrest is typically associated with cerebral and myocardial ischemia/reperfusion (I/R)-injury. Recently, we have demonstrated effects of therapeutic hypothermia (HT) and postconditioning with the volatile anesthetic sevoflurane (SEV) on I/R-mediated mechanisms in the heart and brain [Meybohm et al., PLoS One, 2009; Meybohm et al., Crit Care, 2010]. As the intestine is also highly susceptible to I/R-injury, we investigated the influence of HT and SEV on intestinal I/R-mediated events induced by cardiac arrest and successful resuscitation.. Effects of I/R, HT (12h, 33°C) and a combination of HT with SEV (12h, 2.0vol%) were evaluated in a pig model of cardiac arrest and successful cardiopulmonary resuscitation. Western blotting, ELISA, caspase-3/7 assays, myeloperoxidase (MPO) quantifications and gelatine zymography were performed using intestinal tissue derived 24h after return of spontaneous circulation.. Compared to the normothermia control, HT and HT+SEV resulted in a significant increase in intestinal HIF-1α protein expression (P<0.05). Tissue concentrations of IL-1β were significantly reduced in the HT and HT+SEV group (P<0.05), whereas a reduction of IL-10 levels was only detected in the intestine of animals treated with HT+SEV (P<0.05). A statistically significant increase of intestinal MPO activity was found in the HT+SEV group (P<0.01). Activities of caspase-3 and 7 or matrixmetalloproteinase-2 were not changed in any of the groups investigated, the activity of matrixmetalloproteinase-9 was, however, significantly increased in the HT+SEV group (P<0.05).. HT and postconditioning with SEV influence the expression and activity of several small intestinal proteins that are possibly involved in intestinal I/R-mediated events following successful cardiopulmonary resuscitation.

Topics: Anesthesia, Inhalation; Anesthetics, Inhalation; Animals; Biomarkers; Blotting, Western; Cardiopulmonary Resuscitation; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Female; Heart Arrest; Hypothermia, Induced; Intestine, Small; Male; Methyl Ethers; Peroxidase; Reperfusion Injury; Sevoflurane; Swine; Treatment Outcome

Tubulointerstitial inflammation is the characteristics of renal ischemia reperfusion injury (IRI) that is inevitable in kidney transplantation. Erythropoietin (EPO) has recently been shown to have protective effects on renal IRI by anti-apoptosis and anti-oxidation. Here, the effect and mechanism of EPO on renal IRI were further investigated, with a focus on tubulointerstitial inflammation.. Male Sprague-Dawley rats were administrated with saline or EPO prior to IRI induced by bilateral renal pedicle clamping. Twenty-four hours following reperfusion, the effects of EPO on renal IRI were assessed by renal function and structure, tubulointerstitial myeloperoxidase (MPO) positive neutrophils, and proinflammatory mediator gene expression. The translocation and activity of NF-κB in renal tissues were also evaluated.. Compared with control groups, the EPO treated group exhibited lower serum urea and creatinine levels, limited tubular necrosis with a lower score of renal histological lesion. MPO positive cells in the tubulointerstitial area were greatly increased by IRI, but significantly reduced by the treatment of EPO. The gene expression of proinflammatory cytokines (IL-1β, IL-6, IL-10, and TNF-α) and chemokine (MCP-1) was also significantly decreased by EPO. In addition, less activation and nuclear-translocation of NF-κB was observed in the kidney treated by EPO as well.. EPO improved renal function and structure in IRI rats via reducing neutrophils in the tubulointerstitium, the production of proinflammatory cytokines and chemokine, as well as the activation and nuclear-translocation of NF-κB. EPO may have potential clinical applications as an anti-inflammation agent clinically for a wide range of injury.

Topics: Animals; Apoptosis; Creatinine; Cytokines; Erythropoietin; Kidney; Male; Models, Animal; Necrosis; Nephritis, Interstitial; NF-kappa B; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

The objectives of this study were to determine whether neutrophil depletion with anti-neutrophil serum (ANS) or preconditioning with the hydrogen sulfide (H(2)S) donor NaHS (NaHS-PC) 24 h prior to ischemia-reperfusion (I/R) would prevent postischemic mitochondrial dysfunction in rat intestinal mucosa and, if so, whether calcium-activated, large conductance potassium (BK(Ca)) channels were involved in this protective effect. I/R was induced by 45-min occlusion of the superior mesenteric artery followed by 60-min reperfusion in rats preconditioned with NaHS (NaHS-PC) or a BK(Ca) channel activator (NS-1619-PC) 24 h earlier or treated with ANS. Mitochondrial function was assessed by measuring mitochondrial membrane potential, mitochondrial dehydrogenase function, and cytochrome c release. Mucosal myeloperoxidase (MPO) and TNF-α levels were also determined, as measures of postischemic inflammation. BK(Ca) expression in intestinal mucosa was detected by immunohistochemistry and Western blotting. I/R induced mitochondrial dysfunction and increased tissue MPO and TNF-α levels. Although mitochondrial dysfunction was attenuated by NaHS-PC or NS-1619-PC, the postischemic increases in mucosal MPO and TNF-α levels were not. The protective effect of NaHS-PC or NS-1619-PC on postischemic mitochondrial function was abolished by coincident treatment with BK(Ca) channel inhibitors. ANS prevented the I/R-induced increase in tissue MPO levels and reversed mitochondrial dysfunction. These data indicate that neutrophils play an essential role in I/R-induced mucosal mitochondrial dysfunction. In addition, NaHS-PC prevents postischemic mitochondrial dysfunction (but not inflammation) by a BK(Ca) channel-dependent mechanism.

Topics: Animals; Benzimidazoles; Cytochromes c; Hydrogen Sulfide; Intestinal Diseases; Intestine, Small; Ischemic Preconditioning; Leukocyte Reduction Procedures; Male; Membrane Potential, Mitochondrial; Mitochondria; Mitochondrial Diseases; Neutrophils; Peroxidase; Potassium Channels, Calcium-Activated; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sulfides; Tumor Necrosis Factor-alpha

Acute kidney injury secondary to renal ischemia and reperfusion injury is widely prevalent. Ghrelin, which is a stomach-derived peptide, has been shown to be anti-inflammatory. The purpose of this study was to examine whether human ghrelin has any beneficial effects after renal ischemia and reperfusion injury, and if so, whether ghrelin's action in renal ischemia and reperfusion injury is mediated by the vagus nerve.. Male adult rats were subjected to renal ischemia and reperfusion by bilateral renal pedicle clamping for 60 min, treated intravenously with human ghrelin (4 nmol/rat) or normal saline (vehicle) immediately after reperfusion. After 24 h, the animals were killed and samples were harvested. In separate groups, subdiaphragmatic vagotomy prior to renal ischemia and reperfusion was performed, treated with human ghrelin or vehicle, and at 24 h, blood and organs were harvested.. Renal ischemia and reperfusion injury caused significant increases in the serum levels of tissue injury markers compared with the sham operation. Human ghrelin treatment attenuated serum creatinine and blood urea nitrogen significantly by 55% and 53%, and liver enzymes (aminotransferase [AST] and alanine aminotransferase [ALT]) by 20% and 24%, respectively, compared with the vehicle-treated groups. Tissue water contents, plasma and kidney interleukin-6, and kidney myeloperoxidase activity were decreased. Bcl-2/Bax ratio was increased, and histology of the kidneys was improved. More importantly, prior vagotomy abolished ghrelin's protective effect in tissue injury markers and tissue water contents in renal ischemia and reperfusion injured animals.. Human ghrelin treatment in renal ischemia and reperfusion injured rats attenuated systemic and kidney-specific inflammatory responses. The protection of human ghrelin in renal ischemia and reperfusion injury was mediated by the vagus nerve. These data suggest that ghrelin can be developed as a novel treatment for patients with acute kidney injury induced by renal ischemia and reperfusion injury.

Topics: Animals; bcl-2-Associated X Protein; Blood Urea Nitrogen; Creatinine; Ghrelin; Humans; Interleukin-6; Kidney; Kidney Diseases; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Vagotomy; Vagus Nerve; Water

Proteases and proteinase-activated receptor (PAR) activation are involved in several intestinal inflammatory conditions. We hypothesized that serine proteases and PAR activation could also modulate the intestinal injury induced by ischemia-reperfusion (I-R). C57Bl/6 mice were subjected to 90 minutes of intestinal ischemia followed or not by reperfusion. Sham-operated animals served as controls. After ischemia, plasma and tissue serine protease activity levels were increased compared to the activity measured in plasma and tissues from sham-operated mice. This increase was maintained or further enhanced after 2 and 5 hours of reperfusion, respectively. Trypsin (25 kDa) was detected in tissues both after ischemia and 2 hours of reperfusion. Treatment with FUT-175 (10 mg/kg), a potent serine protease inhibitor, increased survival after I-R, inhibited tissue protease activity, and significantly decreased intestinal myeloperoxidase (MPO) activity and chemokine and adhesion molecule expression. We investigated whether serine proteases modulate granulocyte recruitment by a PAR-dependent mechanism. MPO levels and adhesion molecule expression were significantly reduced in I-R groups pre-treated with the PAR(1) antagonist SCH-79797 (5 mg/kg) and in Par(2)(-/-)mice, compared, respectively, to vehicle-treated group and wild-type littermates. Thus, increased proteolytic activity and PAR activation play a pathogenic role in intestinal I-R injury. Inhibition of PAR-activating serine proteases could be beneficial to reduce post-ischemic intestinal inflammation.

Topics: alpha-Macroglobulins; Animals; Benzamidines; Chemokines; Cysteine Proteinase Inhibitors; Granulocytes; Guanidines; Intestine, Small; Ischemia; Leucine; Male; Mice; Mice, Inbred C57BL; Peroxidase; Protease Inhibitors; Receptor, PAR-1; Receptor, PAR-2; Reperfusion Injury; Serine Proteinase Inhibitors; Trypsin

In the present study, the effects of SCH58261, a selective adenosine A(2A) receptor antagonist that crosses the blood brain barrier (BBB) and 8-(4-sulfophenyl) theophylline (8-SPT), a non-selective adenosine receptor antagonist that acts peripherally, were investigated on cerebral ischemia reperfusion injury (IR). Male Wistar rats (200-250 g) were divided into four groups: (1) sham-operated (SO), IR pretreated with either (2) vehicle (DMSO); (3) SCH58261 (0.01 mg/kg); (4) 8-SPT (2.5 mg/kg). Animals were anesthetized and submitted to occlusion of both carotid arteries for 45 min. All treatments were administered intraperitoneally (i.p.) post carotid occlusion prior to exposure to a 24 h reperfusion period. Ischemic rats showed increased infarct size compared to their control counterparts that corroborated with histopathological changes as well as increased lactate dehydrogenase (LDH) activity in the hippocampus. Moreover, ischemic animals showed habituation deficit, increased anxiety and locomotor activity. IR increased hippocampal glutamate (Glu), GABA, glycine (Gly) and aspartate (ASP). SCH58261 significantly reversed these effects while 8-SPT elicited minimal change. IR raised myeloperoxidase (MPO), tumor necrosis factor-alpha (TNF-α), nitric oxide (NO), prostaglandin E₂ (PGE₂) accompanied by a decrease in interleukin-10 (IL-10), effects that were again reversed by SCH58261, but 8-SPT elicited less changes. Results from the present study point towards the importance of central blockade of adenosine A(2A) receptor in ameliorating hippocampal damage following IR injury by halting inflammatory cascades as well as modulating excitotoxicity.

Topics: Amino Acids; Animals; Arterial Occlusive Diseases; Behavior, Animal; Brain; Carotid Arteries; Inflammation Mediators; L-Lactate Dehydrogenase; Male; Neuroprotective Agents; Nitric Oxide; Peroxidase; Pyrimidines; Rats; Rats, Wistar; Reperfusion Injury; Triazoles

Tumor necrosis factor-alpha (TNF-α) is a central mediator in the hepatic response to ischemia/reperfusion. Short hairpin RNA (shRNA) has been proven to be an effective means of harnessing the RNA interference pathway in mammalian cells. In the current study, we investigated whether silencing TNF-α gene with shRNA can prevent liver ischemic reperfusion injury (IRI).. Male BalB/c mice were randomized to TNF-α shRNA, scramble shRNA, or sham operation groups. TNF-α shRNA and scramble shRNA groups were injected 48 h before inducing IRI. IRI was induced via microaneurysm clamps applied to the left hepatic artery and portal vein. Six hours after reperfusion, IRI injury was examined by serum level of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), liver histopathology, MPO, and MDA level, as well as by relative quantities of TNF-α mRNA.. TNF-α expression induced by ischemia reperfusion in the liver was significantly suppressed after treatment with TNF-α shRNA compared with the group treated with scramble shRNA (P < 0.001). Mice treated with TNF-α shRNA showed lower peak values of AST and ALT than scramble shRNA treated mice (P < 0.001). On histopathologic slides, mice treated with TNF-α shRNA had significantly less ischemia/reperfusion injury based on Suzuki score than the scramble shRNA group, 3.57 ± 2.30 and 8.83 ± 0.98 respectively (P < 0.001), while the sham group was not significantly different from the TNF-alpha shRNA group, 0 ± 0 and 3.57 ± 2.30, respectively (P = 0.075). Liver tissue MDA levels were significantly lower in mice treated with TNF-α shRNA as compared with the group treated with scramble shRNA (P < 0.01). Immunohistochemical staining for MPO was significantly lower in mice treated with TNF-α shRNA compared with the group treated with shRNA (compared with treated with scramble shRNA group.). Liver IRI can be minimized through gene silencing of TNF-α. This may represent a novel therapy in the setting of transplantation and in other conditions associated with IRI of the liver.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Down-Regulation; Genetic Therapy; Liver; Male; Malondialdehyde; Mice; Mice, Inbred BALB C; Peroxidase; Reperfusion Injury; RNA, Small Interfering; Tumor Necrosis Factor-alpha

Hepatic ischemia/reperfusion injury (IRI) occurs in multiple clinical settings, including liver transplantation. The cyclic adenosine monophosphate (cAMP)-dependent protein kinase A (PKA) pathway inhibits hepatocellular apoptosis and regulates toll-like receptor 4-triggered inflammation responses in vitro. Here we examined the function and therapeutic potential of cAMP-PKA activation in a murine (C57/BL6) model of liver warm ischemia (90 minutes) followed by reperfusion. Liver IRI triggered cAMP-PKA activation, whereas the administration of its specific inhibitor, H89, exacerbated hepatocellular damage. Conversely, forskolin therapy, which activates PKA by elevating cAMP levels, protected livers from IRI; this was evidenced by diminished serum alanine aminotransferase levels and well-preserved tissue architecture. Liver protection due to cAMP-PKA stimulation was accompanied by diminished neutrophil and macrophage infiltration/activation, reduced hepatocyte necrosis/apoptosis, and increased cAMP response element-binding protein (CREB) expression and augmented interleukin-10 (IL-10) expression. The neutralization of IL-10 restored liver damage in otherwise ischemia/reperfusion-resistant, forskolin-treated mice. In vitro, cAMP-PKA activation diminished macrophage tumor necrosis factor α, IL-6, and IL-12 in an IL-10-dependent manner and prevented necrosis/apoptosis in primary mouse hepatocyte cultures. Our novel findings in a mouse model of liver IRI document the importance of cAMP-PKA signaling in hepatic homeostasis and cytoprotection in vivo. The activation of cAMP-PKA signaling differentially regulates local inflammation and prevents hepatocyte death, and this provides a rationale for novel therapeutic approaches to combating liver IRI in transplant recipients.

Topics: Animals; Apoptosis; Cells, Cultured; Colforsin; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Disease Models, Animal; Enzyme Inhibitors; Hepatocytes; Interleukin-10; Isoquinolines; Liver; Liver Transplantation; Macrophages; Male; Mice; Mice, Inbred C57BL; Necrosis; Peroxidase; Reperfusion Injury; Signal Transduction; Sulfonamides; Temperature

Intrauterine ischemia-reperfusion (I/R) injury in fetus occurs with multifactorial pathogenesis and results with multiorgan injury including skin. Magnesium has widespread use in obstetric practice. Inn addition to magnesium's tocolytic and neuroprotective properties, it also has free radical reducing effects. The aim of the present study was to demonstrate whether magnesium sulfate could have protective effect on fetal rat skin in intrauterine ischemia-reperfusion (I/R) injury. Fetal skin ischemia was induced by clamping the utero-ovarian arteries bilaterally for 30 min, and reperfusion was achieved by removing the clamps for 60 min in 19-day pregnant rats. Magnesium Sulfate (MgSO(4)) was given to pregnant rats 20 min before I/R injury at the dose of 600 mg/kg in magnesium treatment group. No ischemia reperfusion was applied to control and sham-operated groups. Lipid peroxidation from the skin tissues was determined as thiobarbituric acid reactive substances (TBARS). Myeloperoxidase (MPO) activity was determined for neutrophil activation. The results showed that the levels of TBARS and MPO increased significantly in the fetal rat skin after I/R injury compared to control group. Levels of TBARS and MPO were significantly lower than those of I/R group in Magnesium-treated group. In conclusion, intrauterine ischemia-reperfusion may produce considerable fetal skin injury. Increased TBARS and MPO activity can be inhibited by magnesium treatment. This suggests that magnesium treatment may have protective effect on fetal rat skin in intrauterine I/R injury.

Topics: Animals; Disease Models, Animal; Female; Fetal Diseases; Fetus; Free Radical Scavengers; Lipid Peroxidation; Magnesium Sulfate; Neutrophil Activation; Peroxidase; Pregnancy; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Skin; Thiobarbituric Acid Reactive Substances; Uterine Artery Embolization

Intestinal ischemia/reperfusion (I/R) induces mucosal barrier dysfunction and bacterial translocation (BT). Neutrophil-derived oxidative free radicals have been incriminated in the pathogenesis of ischemic injury in various organs, but their role in the bacteria-containing intestinal tract is debatable. Primed neutrophils are characterized by a faster and higher respiratory burst activity associated with more robust bactericidal effects on exposure to a second stimulus. Hypoxic preconditioning (HPC) attenuates ischemic injury in brain, heart, lung and kidney; no reports were found in the gut. Our aim is to investigate whether neutrophil priming by HPC protects against intestinal I/R-induced barrier damage and bacterial influx. Rats were raised in normoxia (NM) or kept in a hypobaric hypoxic chamber (380 Torr) 17 h/day for 3 weeks for HPC, followed by sham operation or intestinal I/R. Gut permeability was determined by using an ex vivo macromolecular flux assay and an in vivo magnetic resonance imaging-based method. Liver and spleen homogenates were plated for bacterial culturing. Rats raised in HPC showed diminished levels of BT, and partially improved mucosal histopathology and epithelial barrier function compared with the NM groups after intestinal I/R. Augmented cytokine-induced neutrophil chemoattractant (CINC)-1 and -3 levels and myeloperoxidase activity correlated with enhanced infiltration of neutrophils in intestines of HPC-I/R compared with NM-I/R rats. HPC alone caused blood neutrophil priming, as shown by elevated production of superoxide and hydrogen peroxide on stimulation, increased membrane translocation of cytosolic p47(phox) and p67(phox), as well as augmented bacterial-killing and phagocytotic activities. Neutrophil depletion reversed the mucosal protection by HPC, and aggravated intestinal leakiness and BT following I/R. In conclusion, neutrophil priming by HPC protects against I/R-induced BT via direct antimicrobial activity by oxidative respiratory bursts and through promotion of epithelial barrier integrity for luminal confinement of enteric bacteria.

Topics: Animals; Bacterial Translocation; Cell Membrane; Cells, Cultured; Chemokine CXCL1; Chemokine CXCL2; Hypoxia; Intestinal Mucosa; Intestines; Liver; Male; Neutrophils; Permeability; Peroxidase; Rats; Rats, Wistar; Reactive Oxygen Species; Reperfusion Injury; Spleen

To explore the protective effect of the phosphodiesterase-5 inhibitor, sildenafil, on lung ischemia-reperfusion injury, 30 rats were randomly divided into 3 groups of 10: a sham-operated group A, a lung ischemia-reperfusion injury group B, and a sildenafil preconditioned group C. A 0.1% sildenafil solution was administrated orally 2 h before establishing an in-vivo lung ischemia-reperfusion model in group C; 0.9% normal saline solution was used in the controls. The lung wet-to-dry ratio, malondialdehyde content, myeloperoxidase and nitric oxide synthase activity in groups B and C were significant higher than those in group A, while the partial pressure of oxygen in arterial blood and cyclic guanosine-3',5'-monophosphate content in groups B and C were significant lower than those in group A. Compared to group B, lung wet/dry ratio, malondialdehyde content, myeloperoxidase and nitric oxide synthase activity in group C were significantly lower, while arterial O(2) and cyclic guanosine-3',5'-monophosphate content in group C were significantly higher. The expected histological and cytological changes were significantly alleviated in group C. Oral preconditioning with sildenafil prevented rat lung ischemia-reperfusion injury and improved pulmonary function. The mechanisms of this effect might be prevention of cyclic guanosine monophosphate degradation and inhibition of nitric oxide synthase activity.

Topics: Alveolar Epithelial Cells; Animals; Cyclic GMP; Endothelium, Vascular; Lung Diseases; Male; Malondialdehyde; Nitric Oxide Synthase; Peroxidase; Phosphodiesterase 5 Inhibitors; Piperazines; Purines; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sildenafil Citrate; Sulfones

Restricting oxygen delivery during the reperfusion phase of cardiopulmonary bypass (CPB) protects the heart, but effects on lung ischemia reperfusion (IR) in CPB are unknown. We examined whether extracellular high mobility group box 1 (HMGB1) mediated inflammation during early lung IR injury in CPB. Fourteen healthy canines received CPB with 60 minutes of aortic clamping and cardioplegic arrest, followed by 90 minutes reperfusion. Following surgery, the animals were randomized into control (n = 7) or test (n = 7) groups. Control animals received a constant level of 80% FiO(2) during the entire procedure, and the test group received a gradual increase in FiO(2) during the first 25 minutes of reperfusion. In the test group, the FiO(2) was initiated at 40% and increased by 10% every 5 minutes, to 80%. Histology, lung injury variables, HMGB1 expression, and inflammatory responses were assessed at baseline (T1) and at 25 minutes (T2) and 90 minutes (T3) after starting reperfusion. Treatment with controlled oxygen significantly suppressed lung pathologies, lung injury variables, and inflammatory responses (all P < .001). After lung IR injury, HMGB1 mRNA and protein expressions were significantly decreased in the controlled oxygen group (all P < .001). Controlled oxygen reperfusion is protective in the early stages of lung IR injury in a canine CPB model, and this protection is linked to HMGB1 downregulation.

Topics: Acute Lung Injury; Animals; Base Sequence; Cardiopulmonary Bypass; Cytokines; Disease Models, Animal; Dogs; Down-Regulation; Female; HMGB1 Protein; Lung; Male; Malondialdehyde; Oxygen; Peroxidase; Reperfusion Injury; RNA, Messenger

Recent evidence suggests that cell therapy such as the injection of bone marrow-derived mononuclear cells (BMMNCs) can exert protective effects in various conditions associated with ischemia-reperfusion injury. Here, we investigate the effects of BMMNCs on the organ injury/dysfunction induced by hemorrhagic shock (HS). Thirty-seven anesthetized male Wistar rats were subjected to hemorrhage by reducing mean arterial pressure to 35 ± 5 mmHg for 90 min, followed by resuscitation with 20 mL/kg Ringer's lactate administered over 10 min and 50% of the shed blood over 50 min. Rats were killed 4 h after the onset of resuscitation. Bone marrow-derived mononuclear cells were freshly isolated from rat tibias and femurs using Percoll density gradient centrifugation, and BMMNCs (1 × 10 cells per rat in 1 mL/kg phosphate-buffered saline, i.v.) were administered on resuscitation. Hemorrhagic shock resulted in significant organ injury/dysfunction (renal, hepatic, neuromuscular) and inflammation (hepatic, lung). In rats subjected to HS, administration of BMMNCs significantly attenuated (i) organ injury/dysfunction (renal, hepatic, neuromuscular) and inflammation (hepatic, lung), (ii) increased the phosphorylation of Akt and glycogen synthase kinase-3β, (iii) attenuated the activation of nuclear factor-κB, (iv) attenuated the increase in extracellular signal-regulated kinase 1/2 phosphorylation, and (v) attenuated the increase in expression of intercellular adhesion molecule-1. Our findings suggest that administration of BMMNCs protects against the induction of early organ injury/dysfunction caused by severe HS by a mechanism that may involve activation of Akt and the inhibition of glycogen synthase kinase-3β and nuclear factor-κB.

Topics: Animals; Bone Marrow Transplantation; Cell Transplantation; Glycogen Synthase Kinase 3; Liver; Lung; Male; MAP Kinase Signaling System; Monocytes; Oncogene Protein v-akt; Peroxidase; Phosphorylation; Rats; Rats, Wistar; Reperfusion Injury; Shock, Hemorrhagic; Transcription Factor RelA

Hemorrhagic shock and resuscitation is frequently associated with liver ischemia-reperfusion injury. The aim of the study was to investigate whether hypoxemic resuscitation attenuates liver injury.. Anesthetized, mechanically ventilated New Zealand white rabbits were exsanguinated to a mean arterial pressure of 30 mmHg for 60 minutes. Resuscitation under normoxemia (Normox-Res group, n = 16, PaO(2) = 95-105 mmHg) or hypoxemia (Hypox-Res group, n = 15, PaO(2) = 35-40 mmHg) followed, modifying the FiO(2). Animals not subjected to shock constituted the sham group (n = 11, PaO(2) = 95-105 mmHg). Indices of the inflammatory, oxidative and nitrosative response were measured and histopathological and immunohistochemical studies of the liver were performed.. Normox-Res group animals exhibited increased serum alanine aminotransferase, tumor necrosis factor--alpha, interleukin (IL) -1β and IL-6 levels compared with Hypox-Res and sham groups. Reactive oxygen species generation, malondialdehyde formation and myeloperoxidase activity were all elevated in Normox-Res rabbits compared with Hypox-Res and sham groups. Similarly, endothelial NO synthase and inducible NO synthase mRNA expression was up-regulated and nitrotyrosine immunostaining increased in animals resuscitated normoxemically, indicating a more intense nitrosative stress. Hypox-Res animals demonstrated a less prominent histopathologic injury which was similar to sham animals.. Hypoxemic resuscitation prevents liver reperfusion injury through attenuation of the inflammatory response and oxidative and nitrosative stresses.

Topics: Alanine Transaminase; Animals; Cytokines; Hypoxia; Liver; Male; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Oxidative Stress; Oxygen; Peroxidase; Rabbits; Reactive Nitrogen Species; Reperfusion Injury; RNA, Messenger; Shock, Hemorrhagic

Intestinal ischemia-reperfusion (I/R) injury is a devastating complication in the perioperative period. Dexmedetomidine is commonly applied in the perioperative period. The authors aimed to determine the effects of different doses of dexmedetomidine (given before or after intestinal ischemia) on intestinal I/R injury and to explore the underlying mechanisms.. Intestinal I/R injury was produced in rat by clamping the superior mesenteric artery for 1 h followed by 2 h reperfusion. Intravenous infusion of dexmedetomidine was performed at 2.5, 5, and 10 μg · kg(-1) · h(-1) for 1 h before or after ischemic insult. In addition, yohimbine hydrochloride was administered intravenously to investigate the role of α2 adrenoreceptor in the intestinal protection conferred by dexmedetomidine.. Intestinal I/R increased mortality of rats and caused notable intestinal injury, as evidenced by statistically significant increases in Chiu's scores; serum diamine oxidase and tumor necrosis factor-α concentration, accompanied by increases in the intestinal mucosal malondialdehyde concentration; myeloperoxidase activity; and epithelial cell apoptosis (all P < 0.05 vs. Sham). Except malondialdehyde and myeloperoxidase, all changes were improved by the administration of 5 μg · kg(-1) · h(-1) dexmedetomidine before ischemia (all P < 0.05 vs. Injury) but not after ischemia. Infusion of 2.5 μg · kg(-1) · h(-1) dexmedetomidine before or after ischemia produced no beneficial effects, and infusion of 10 μg · kg(-1) · h(-1) dexmedetomidine led to severe hemodynamic suppression. Yohimbine abolished the intestinal protective effect of the 5 μg · kg(-1) · h(-1) dexmedetomidine infusion before ischemia and was accompanied by the disappearance of its antiapoptotic and antiinflammatory effect.. Dexmedetomidine administration before, but not after, ischemia dose-dependently protects against I/R-induced intestinal injury, partly by inhibiting inflammatory response and intestinal mucosal epithelial apoptosis via α2 adrenoreceptor activation.

Topics: Adrenergic alpha-Agonists; Amine Oxidase (Copper-Containing); Animals; Apoptosis; Blood Gas Analysis; Caspase 3; Dexmedetomidine; Dose-Response Relationship, Drug; Hemodynamics; Intestinal Mucosa; Intestines; Lactic Acid; Male; Malondialdehyde; Peroxidase; Rats; Rats, Sprague-Dawley; Receptors, Adrenergic, alpha-2; Reperfusion Injury; Survival Analysis; Tumor Necrosis Factor-alpha

Monocyte chemoattractant protein-1 (MCP-1) is believed to play a crucial role in lung ischaemia-reperfusion injury (LIRI). Ischaemic preconditioning (IP) has been shown to protect several organs from ischaemia-reperfusion (IR) injury, although less is known about IP's effect on MCP-1 modulation. The objective of this study was to investigate IP's effect on MCP-1 expression in lung tissue and its relationship with oxidative stress and proinflammatory cytokine production in an experimental LIRI model.. Two groups (IP and control groups) of seven large white pigs underwent a lung autotransplant (left pneumonectomy, ex situ superior lobectomy and lower lobe reimplantation). Before pneumonectomy was performed in the study group, IP was induced with two cycles of 5 min of left pulmonary artery occlusion with a 5 min interval of reperfusion between the two occlusions. Blood samples and lung biopsies were obtained at prepneumonectomy (PPn), at prereperfusion (PRp) and up to 30 min after reperfusion of the implanted lobe (Rp-10' and Rp-30'). Haemodynamic and blood-gas measurements, evaluation of oxidative stress in lung tissue and MCP-1, tumour necrosis factor-α (TNF-α) and IL-1 protein and mRNA measurements in lung tissue were performed. Nonparametric tests were used to compare differences between groups. Data are expressed as mean ± SEM.. In control lungs, MCP-1 protein levels were found to be higher at PRp, Rp-10' and Rp-30' than at PPn (0.59 ± 0.1 vs. 0.21 ± 0.05, 0.47 ± 0.01 vs. 0.21 ± 0.05 and 0.56 ± 0.01 vs. 0.21 ± 0.05, respectively; P < 0.05). These differences were not evident in the IP group. MCP-1 levels at PRp, Rp-10' and Rp-30' were significantly higher in the control group than in the IP group (0.59 ± 0.1 vs. 0.15 ± 0.02, 0.47 ± 0.01 vs. 0.13 ± 0.01 and 0.56 ± 0.01 vs. 0.27 ± 0.01, respectively; P < 0.05). MCP-1, TNF-α and IL-1 mRNA expressions were lower at PRp, Rp-10' and Rp-30' (control vs. IP group, P < 0.05) when IP was carried out. Lipid peroxidation metabolites and myeloperoxidase activity increase in lung tissue were prevented by IP.. In this model, LIRI induced the expression of MCP-1 and the proinflammatory proteins TNF-α and IL-1 in control lungs. IP significantly reduced the expression of these chemokines and cytokines. These features may explain the reduction of oxidative stress observed with IP.

Topics: Animals; Chemokine CCL2; Cytokines; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Gene Expression Regulation; Hemodynamics; Inflammation Mediators; Ischemic Preconditioning; Lung; Lung Transplantation; Oxidative Stress; Oxygen; Partial Pressure; Peroxidase; Reperfusion Injury; RNA, Messenger; Sus scrofa

Acute kidney injury (AKI), which occurs during renal transplantation and cardiovascular surgery, is a major clinical problem associated with high mortality, and has limited treatment options. Anti-inflammation therapy has been suggested to improve the course and outcome of AKI. In this study, we hypothesized that ESeroS-GS, a vitamin E derivative, inhibits cytokine production and prevents renal ischemia-reperfusion (I/R) injury in rats.. Rats received an intravenous infusion of ESeroS-GS or saline, and underwent experimentally-induced renal I/R injury or sham treatment. Rats were sacrificed after 60 min of ischemia and 24 h of reperfusion. To evaluate the renal protective effects of ESero-GS, renal function was examined, kidneys were histologically assessed, levels of myeloperoxidase (MPO) and serum cytokines were measured, and caspase 3/7 activity was determined.. ESeroS-GS attenuated I/R-induced histologic alterations, reduced levels of MPO and serum BUN, Cre, TNF-α, and IL-6, and decreased caspase 3/7 activity in kidneys of rats subjected to renal I/R injury.. ESeroS-GS attenuated renal injury after I/R by reducing serum cytokine levels. Our findings suggest that ESeroS-GS may have therapeutic potential against various human I/R conditions.

Topics: Animals; Benzopyrans; Blood Urea Nitrogen; Caspase 3; Caspase 7; Indoles; Interleukin-6; Kidney; Male; Models, Animal; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Tumor Necrosis Factor-alpha; Vitamin E

To evaluate biochemically and histopathologically the effects of Nigella sativa (NS) in experimental ischemia and ischemia/reperfusion (I/R) injury in rat ovaries.. Thirty-six female rats were divided into 6 groups: group I = sham operation; group II = 500 mg/kg NS + sham operation; group III = bilateral ovarian ischemia; group IV = 500 mg/kg NS + ischemia; group V = 3-hour period of ischemia + 3-hour reperfusion, and group VI: 3-hour period of ischemia + 500 mg/kg NS 2.5 h after the induction of ischemia + 3-hour reperfusion. At the end of ischemia, the bilateral vascular clips were removed, and 3-hour reperfusion was continued. IL-1β, IL-6, and TNF-α cytokine levels in serum, and superoxide dismutase (SOD), myeloperoxidase (MPO), glutathione (GSH), and malondialdehyde (MDA) levels were determined.. I/R increased the MDA level and MPO activity while significantly decreasing the SOD activity and GSH level when compared to the sham. The 500-mg/kg dose of NS before I/R reversed the trend in MDA levels, MPO activity, SOD activity, and GSH levels. Ischemia and I/R increased the serum levels of IL-1β, IL-6, and TNF-α, while the administration of NS decreased the serum levels of these cytokines.. The administration of NS is effective in reversing tissue damage induced by ischemia and/or I/R in ovaries.

Topics: Animals; Female; Glutathione; Interleukin-1beta; Interleukin-6; Malondialdehyde; Nigella sativa; Oophoritis; Ovary; Oxidative Stress; Peroxidase; Phytotherapy; Plant Preparations; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase; Torsion, Mechanical; Tumor Necrosis Factor-alpha

Ischemia-reperfusion (I/R) event in vascular and nervous system has been documented to rising ischemic and vasculitic neuropathic pain, clinically resembles the complex regional pain syndrome (CRPS). The present study evaluated the effect of montelukast, a cysteinyl leukotriene receptor (Cys-LTC(4) and Cys-LTD(4)) antagonist on ischemia -reperfusion (I/R) induced vasculitic neuropathic pain in rats.. Behavioral parameters were assessed at different time intervals (i.e. 0, 1, 7, 14 and 21st day) and biochemical analysis in sciatic nerve tissue samples were also performed along with histopathological studies.. Behavioral pain assessment has shown increase in paw and tail withdrawal threshold in montelukast treated groups against thermal and mechanical stimuli as compared to I/R control group. We observed a decrease in the total calcium, thiobarbituric acid reactive substance (TBARS) and myeloperoxidase (MPO) activity levels, whereas there is rise in reduced glutathione level in montelukast treated groups as compared to I/R control group. However, significant behavioral and biochemical results were observed only in medium and high dose of treated groups which were comparable to normal control group. Moreover, histopathological study has revealed the reduction of I/R induced neuronal edema and axonal degeneration due to montelukast.. Montelukast has ameliorated I/R induced vasculitic neuropathic pain, these effects may be due to inhibition of lipid peroxidation, reduction of oxidative stress, release of inflammatory mediators and neuroprotective actions. Hence, it could be used as a novel therapeutic agent for the management of vasculitic inflammation related neuropathic pain.

Topics: Acetates; Animals; Behavior, Animal; Calcium; Cyclopropanes; Glutathione; Hot Temperature; Immersion; Leukotriene Antagonists; Neuralgia; Pain Measurement; Peroxidase; Physical Stimulation; Quinolines; Rats; Rats, Wistar; Reaction Time; Reperfusion Injury; Sciatic Nerve; Sulfides; Thiobarbituric Acid Reactive Substances; Vasculitis

Stroke is a major cause of mortality and disability worldwide. Presently, recombinant tissue plasminogen activator is the only approved drug for the management of acute ischemic stroke. However, it has limitations like narrow therapeutic window and increased risk of intracranial hemorrhage. In previous studies, immunosuppressive agents such as cyclosporine A and tacrolimus have shown neuroprotection by improving neurological functions and infarct volume in models of ischemic stroke. Therefore, the present study was designed to evaluate the effect of mycophenolate mofetil (MMF) on the cerebral ischemic injury in the middle cerebral artery occlusion (MCAo) model in rats. MCAo was carried out in male Wistar rats by inserting an intraluminal thread. One hour after MCAo, the animals were treated with MMF (50, 100, 200mg/kg, i.p.). Reperfusion was done after 2h of occlusion. Thirty minutes after reperfusion, animals were subjected to diffusion-weighted magnetic resonance imaging for assessment of neuroprotective effect of MMF. Twenty four hours after MCAo, motor performance was assessed and the animals were euthanized for estimation of brain malondialdehyde, glutathione, myeloperoxidase and nitric oxide levels. The effect of MMF on apoptosis was also evaluated. MMF significantly attenuated the percent infarct area, apparent diffusion coefficient and signal intensity as compared to a vehicle treated group. Treatment with MMF prevented the motor impairment and significantly reversed the changes in levels of malondialdehyde, glutathione, myeloperoxidase and nitric oxide. MMF treatment significantly reduced the apoptosis. Data of the present study indicate neuroprotective effect of MMF in the experimental model of ischemic stroke.

Topics: Animals; Glutathione; Hand Strength; Infarction, Middle Cerebral Artery; Magnetic Resonance Imaging; Male; Malondialdehyde; Mycophenolic Acid; Neuroimaging; Neuroprotective Agents; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Rotarod Performance Test

Renal inflammation has an important role in the development of ischemia-reperfusion injury of the kidney. Cysteinyl leukotrienes have been implicated in many inflammatory conditions. The aim of this study was to investigate the ability of the cysteinyl leukotriene receptor blocker, zafirlukast, to alleviate renal dysfunction and injury in a rat model of renal ischemia-reperfusion injury.. We induced renal ischemia for 45 min, followed by 24 h reperfusion. We gave zafirlukast at a dose of 20 mg/kg/d for 3 d before ischemia-reperfusion. At the end of the reperfusion (24 h), we collected blood samples to measure blood urea nitrogen, creatinine, tumor necrosis factor-α, intercellular adhesion molecule-1, and nitrite/nitrate. We took kidney samples for histological and immunohistochemical assessment, and to measure malondialdehyde, glutathione content, and myeloperoxidase activity.. Induction of renal ischemia-reperfusion resulted into renal dysfunction, as indicated by elevated levels of blood urea nitrogen and serum creatinine, serum nitrite and nitrate, serum tumor necrosis factor-α, and intercellular adhesion molecule-1. An oxidative stress marker, renal malondialdehyde concentration, was increased, whereas renal reduced glutathione content was decreased. Myeloperoxidase activity, suggestive of neutrophil infiltration, was elevated in renal tissues. Histological changes confirmed these biochemical changes, as did P-selectin overexpression in renal tissues subjected to ischemia-reperfusion. Administration of zafirlukast before ischemia-reperfusion improved renal functions and reduced serum levels of nitrite and nitrate, tumor necrosis factor-α, and intercellular adhesion molecule-1, renal concentration of myeloperoxidase activity, and malondialdehyde concentration, whereas increased renal reduced glutathione concentration. Moreover, zafirlukast reduced histopathological features of tubular injury and P-selectin overexpression in both cortex and medulla.. These results demonstrate that zafirlukast significantly reduces the severity of ischemic acute renal failure, probably via anti-inflammatory action, reduction of neutrophil infiltration into renal tissues, and oxidative stress subsequent to an attenuation of P-selectin expression.

Topics: Animals; Disease Models, Animal; Indoles; Intercellular Adhesion Molecule-1; Kidney Diseases; Leukotriene Antagonists; Lipid Peroxidation; Male; Neutrophils; Nitrates; Nitrites; Oxidative Stress; P-Selectin; Peroxidase; Phenylcarbamates; Rats; Rats, Wistar; Receptors, Leukotriene; Reperfusion Injury; Sulfonamides; Tosyl Compounds; Tumor Necrosis Factor-alpha

Studies assessing the effects of partial-hepatic ischemia/reperfusion (I/R) injury focused on the damage to the ischemic-lobe, whereas few data are available on non-ischemic lobe. This study investigated whether acute liver I/R does affect non-ischemic lobe function via modulation of extracellular matrix remodeling. Male Sprague-Dawley rats underwent left lateral- and median-lobe ischemia for 30 min and reperfusion for 60 min or sham operation. After reperfusion, blood samples and hepatic biopsies from both the ischemic (left-lobe, LL) and the non-ischemic lobe (right-lobe, RL) were collected. Serum hepatic enzymes and TNF-alpha, tissue matrix metalloproteinases (MMP-2, MMP-9), liver morphology, malondialdehyde (MDA), and myeloperoxidase (MPO) were evaluated. Liver I/R injury was confirmed by altered increased hepatic enzymes and TNF-alpha. I/R induced an altered morphology and an increase in MMP-2 and MMP-9 activity not only in left-ischemic lobe (LL) but also in the right-non-ischemic (RL) lobe. A lobar difference was detected for MDA formation and MPO activity in both sham and I/R submitted rats, with higher levels in the left lobe for both groups. This study indicates that an increase in MMPs, which may be TNF-alpha-mediated, occurs in both the ischemic- and the non-ischemic lobes; the heterogeneous lobe concentrations of MDA and MPO suggest that the random sampling of liver tissue should be avoided.

Topics: Animals; Extracellular Matrix; Ischemia; Liver; Male; Malondialdehyde; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha; Up-Regulation

We assessed the antioxidant activity of dexmedetomidine (Dex) administered during the ischemic period in a rabbit model of mesenteric ischemia/reperfusion (I/R) injury using biochemical and histopathological methods.. A total of 24 male New Zealand white rabbits weighing between 2.5 and 3.0 kg were randomly divided into three groups: the sham group (Group S, n = 8), the I/R group (Group I/R, n = 8), and the I/R plus Dex treatment group (Group Dex, n = 8). In the I/R group, ischemia was achieved with 60 min of mesenteric occlusion. The sham group provided normal basal values. The rabbits in Group I/R were operated to achieve I/R. Group Dex received intravenous Dex 30 min after the commencement of reperfusion (10 μg/kg Dex was infused within 10 min, and then a maintenance dose of 10 μg/kg/h Dex was infused intravenously). For the measurement of tissue malondialdehyde, total antioxidant status, total oxidant status, lipid hydroperoxide levels, superoxide dismutase, catalase, and myeloperoxidase activity levels in the renal tissue samples of animals, the rabbits in each group were sacrificed 3 h after reperfusion. The histopathological examination scores were determined using the intestinal and renal tissues.. The mean malondialdehyde, total oxidant status, myeloperoxidase, and lipid hydroperoxide levels were significantly higher in Group I/R than in Groups S and Dex (P < 0.05). There also were significant decreases in the mean total antioxidant status, catalase, and superoxide dismutase activities in Group I/R compared with Groups S and Dex (P < 0.05). The histopathological examination scores of the intestinal and renal tissues were significantly higher in Group I/R compared with Groups S and Dex (P < 0.05).. Dex treatment may have biochemical and histopathological benefits by preventing I/R-related cellular damage of intestinal and renal tissues as shown in an experimental mesenteric ischemia model. The preference to use Dex for anesthesia during the mesenteric ischemia procedure may attenuate I/R injury in intestinal and renal tissues.

Topics: Acute Disease; Adrenergic alpha-2 Receptor Agonists; Animals; Antioxidants; Arterial Occlusive Diseases; Dexmedetomidine; Disease Models, Animal; Intestinal Mucosa; Intestines; Kidney; Lipid Peroxidation; Male; Malondialdehyde; Mesenteric Arteries; Oxidants; Peroxidase; Rabbits; Reperfusion Injury; Treatment Outcome

Acute kidney injury (AKI) in humans has few therapeutic options. In experimental models, administration of progenitor cells facilitates recovery from AKI. Human umbilical cord-derived CD133(+) progenitor cells promote endothelial repair in ischemic limb, heart and brain tissue.. We examined the effects of human CD133(+) progenitor cells in bilateral ischemia-reperfusion (I/R) kidney injury in non-obese diabetic severe combined immunodeficient mice. CD133(+) cells from human cord blood were injected intravenously at the time of reperfusion and the extent of injury was determined by plasma biochemistry and kidney histology.. In mice with I/R, fluorescently labeled CD133(+) cells were detected in blood 2 min after injection but decreased rapidly thereafter with no evidence of homing to the kidneys. In mice subjected to I/R, CD133(+) cells significantly increased plasma urea and Cr at 24 h compared to vehicle- or CD133(-) cell-treated mice. CD133(+) cells exacerbated tubular necrosis and apoptosis, increased plasma tumor necrosis factor-α and increased kidney neutrophil infiltration. In contrast, CD133(+) cells did not affect tubular cell proliferation. Administration of CD133(+) cells to FVB/N mice post-I/R also augmented kidney injury.. These data indicate that human cord blood-derived CD133(+) cells unexpectedly exacerbate ischemic AKI in mice, possibly through soluble factors. Our study highlights the importance of caution in cell-based therapies for human AKI.

Topics: AC133 Antigen; Acute Kidney Injury; Animals; Antigens, CD; Apoptosis; Cell Proliferation; Cord Blood Stem Cell Transplantation; Cytokines; Fetal Blood; Glycoproteins; Humans; Inflammation Mediators; Kidney; Male; Mice; Mice, Inbred NOD; Mice, SCID; Neutrophils; Peptides; Peroxidase; Reperfusion Injury; Transplantation, Heterologous

Antithymocyte therapy, specifically antithymocyte globulin (ATG; Thymoglobulin), is increasingly being used in organ transplantation to reduce allograft rejection. The T-lymphocyte has been purported to also play a role in ischemia and reperfusion injury (IRI); however, it has not been well studied. Our aim is to determine if ATG treatment impacts murine intestinal IRI.. Under anesthesia, male C57BL6 mice underwent 100 minutes of warm intestinal IRI by clamping the superior mesenteric artery. The treatment group received rabbit anti-murine ATG (10 mg/kg) intraperitoneally 6 hours before IRI. Separate survival and analysis groups were performed. Intestinal tissue was procured at 4 and 24 hours after IRI. Tissue analysis included hematoxylin-eosin staining, CD3, CD4, and CD8 immunostaining, myeloperoxidase assay (MPO), quantitative real-time polymerase chain reaction studies, and Western blot.. ATG treatment led to marked improvement in 7-day survival and a reduction in tissue injury by histology. MPO was also reduced, and immunostaining confirmed a significant reduction in CD3(+), CD4(+), and CD8(+) infiltrating cells in the treatment group. Quantitative real-time polymerase chain reaction analysis revealed the decreased expression of tumor necrosis factor-α, interferon-inducible protein 10, monocyte chemotactic protein-1, interferon-γ, interleukin-2, and increased production of interleukins -13 and -10 in the treatment group. Western blot analysis revealed decreased caspase-3 and increased signal transducer and activator of transcription 6 levels in the ATG-treated group.. This study is the first to show that ATG treatment ameliorates intestinal IRI. Treatment with ATG leads to reduced local infiltration by T-lymphocytes, with fewer inflammatory and chemotactic programs and less apoptosis. Treatment also is associated with a T(H)2-type cytokine switch. These novel findings suggest that T-lymphocytes represent important mediators of intestinal IRI and that ATG therapies may be beneficial in the prevention of IRI.

Topics: Animals; Antigens, CD; Antilymphocyte Serum; Blotting, Western; Intestinal Diseases; Intestinal Mucosa; Intestines; Male; Mice; Mice, Inbred C57BL; Peroxidase; Real-Time Polymerase Chain Reaction; Reperfusion Injury

The purpose of the present study was to determine the effects of interleukin-37 (IL-37) on liver cells and on liver inflammation induced by hepatic ischemia/reperfusion (I/R).. Mice were subjected to I/R. Some mice received recombinant IL-37 (IL-37) at the time of reperfusion. Serum levels of alanine aminotransferase, and liver myeloperoxidase content were assessed. Serum and liver tumor necrosis factor-α (TNF-α), macrophage inflammatory protein-2 (MIP-2) and keratinocyte chemokine (KC) were also assessed. Hepatic reactive oxygen species (ROS) levels were assessed. For in vitro experiments, isolated hepatocytes and Kupffer cells were treated with IL-37 and inflammatory stimulants. Cytokine and chemokine production by these cells were assessed. Primary hepatocytes underwent induced cell injury and were treated with IL-37 concurrently. Hepatocyte cytotoxicity and Bcl-2 expression were determined. Isolated neutrophils were treated with TNF-α and IL-37 and neutrophil activation and respiratory burst were assessed.. IL-37 reduced hepatocyte injury and neutrophil accumulation in the liver after I/R. These effects were accompanied by reduced serum levels of TNF-α and MIP-2 and hepatic ROS levels. IL-37 significantly reduced MIP-2 and KC productions from lipopolysaccharide-stimulated hepatocytes and Kupffer cells. IL-37 significantly reduced cell death and increased Bcl-2 expression in hepatocytes. IL-37 significantly suppressed TNF-α-induced neutrophil activation.. IL-37 is protective against hepatic I/R injury. These effects are related to the ability of IL-37 to reduce proinflammatory cytokine and chemokine production by hepatocytes and Kupffer cells as well as having a direct protective effect on hepatocytes. In addition, IL-37 contributes to reduce liver injury through suppression of neutrophil activity.

Topics: Alanine Transaminase; Animals; Anti-Inflammatory Agents; Cells, Cultured; Chemokine CXCL1; Chemokine CXCL2; Disease Models, Animal; Dose-Response Relationship, Drug; Hepatitis; Hepatocytes; Humans; Inflammation Mediators; Interleukin-1; Kupffer Cells; Liver; Male; Mice; Mice, Inbred C57BL; Neutrophil Activation; Neutrophil Infiltration; Neutrophils; Peroxidase; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-bcl-2; Recombinant Proteins; Reperfusion Injury; Superoxides; Time Factors; Tumor Necrosis Factor-alpha

Rhizophora mangle, the red mangrove, has long been known as a traditional medicine. Its bark has been used as astringent, antiseptic, hemostatic, with antifungic and antiulcerogenic properties. In this paper, we aimed to evaluate the antioxidant properties of a buthanolic fraction of the R. mangle bark extract (RM) against experimental gastric ulcer in rats. Unib-Wh rats received pretreatment of R. mangle after the induction of gastric injury with absolute ethanol and ischemia-reperfusion. Gastric tissues from both methods were prepared to the enzymatic assays, the levels of sulfhydril compounds (GSH), lipid peroxides (LPO), and the activities of glutathione reductase (GR), glutathione peroxidase (GPx), superoxide dismutase (SOD) and myeloperoxidase (MPO) were measured. The RM protected the gastric mucosa in both methods used, ethanol-induced gastric ulcer and ischemia-reperfusion, probably, by modulating the activities of the enzymes SOD, GPx, and GR and increasing or maintaining the levels of GSH; in addition, LPO levels were reduced. The results suggest that the RM antioxidant activity leads to tissue protection; thus one of the antiulcer mechanisms present on the pharmacological effects of R. mangle is the antioxidant property.

Topics: Animals; Antioxidants; Catalase; Ethanol; Glutathione; Glutathione Peroxidase; Lipid Peroxidation; Lipid Peroxides; Male; Peroxidase; Plant Bark; Plant Extracts; Rats; Reperfusion Injury; Rhizophoraceae; Stomach Ulcer; Superoxide Dismutase

The role of complement in ischemia/reperfusion-induced fetal growth restriction and fetal loss is unknown. C5-deficient or wild type timed-pregnant mice were subjected to unilateral uterine ischemia/reperfusion on gestation day 13, either by (1) partial flow restriction by right ovarian artery clamping for 30 min, or (2) total flow restriction by clamping both ovarian and uterine arteries for 5 min. Ischemia/reperfusion-challenged pregnancy outcomes were compared to sham-operated controls 5 days later. Ischemia/reperfusion-treated wild type mice exhibited significantly increased bilateral fetal loss, which was greater in total flow restriction than in partial flow restriction, and decreased fetal weights, which were the same in total flow restriction and partial flow restriction for the surviving fetuses. Placental weights were unchanged by treatments. Ischemia/reperfusion increased uterine, but not placental, myeloperoxidase activity, which correlated with fetal loss. In contrast, C5-deficient mice were protected from both fetal growth restriction and fetal loss, and exhibited no increase in myeloperoxidase activity. These results demonstrate that unilateral uterine ischemia/reperfusion results in bilateral fetal loss and fetal growth restriction, mediated by a systemic mechanism. In the current model, this pathological process is completely dependent on intact complement component 5.

Topics: Animals; Complement C5; Disease Models, Animal; Enzyme Activation; Female; Fetal Death; Fetal Growth Retardation; Humans; Mice; Mice, Mutant Strains; Peroxidase; Placenta; Pregnancy; Reperfusion Injury; Uterus

Nitrite is an intrinsic signaling molecule with potential therapeutic implications in mammalian ischemia/reperfusion (I/R) injury of the heart, liver, and kidney. Although limb muscle compression and subsequent reperfusion are the causative factors in developing crush syndrome (CS), there has been no report evaluating the therapeutic effects of nitrite on CS. We therefore tested whether nitrite could be a therapeutic agent for the treatment of CS.. To create a CS model, anesthetized rats were subjected to bilateral hind limb compression with rubber tourniquets for 5 hours, followed by reperfusion for 0 hour to 6 hours while monitoring blood pressure. Saline for the CS group or sodium nitrite (NaNO(2)-100, 200, and 500 μmol/kg) for the nitrite-treated CS groups was intravenously administered immediately before reperfusion. Blood and tissue samples were collected for biochemical analysis.. Tissue nitrite levels in injured muscles were significantly reduced in the CS group compared with the sham group during I/R injury. Nitrite administration to CS rats restored nitric oxide bioavailability by enhancing nitrite levels of the muscle, resulting in a reduction of rhabdomyolysis markers such as potassium, lactate dehydrogenase, and creatine phosphokinase. Nitrite treatment also reduced plasma levels of interleukin-6 and myeloperoxidase activities in muscle and lung tissues, finally resulting in a dose-dependent improvement of survival rate from 24% (CS group) to 36% (NaNO(2)-100 group) and 64% (NaNO(2)-200 and 500 groups).. These results indicate that nitrite reduces I/R-induced muscle damage through its cytoprotective action and contributes to improved survival rate in a rat CS model.

Topics: Analysis of Variance; Animals; Blood Pressure Determination; Crush Syndrome; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Hemodynamics; Hindlimb; Interleukin-6; Kaplan-Meier Estimate; Male; Muscle, Skeletal; Nitrites; Peroxidase; Random Allocation; Rats; Rats, Wistar; Reference Values; Reperfusion Injury; Rhabdomyolysis; Risk Factors; Survival Analysis; Treatment Outcome

Renal injury as a result of ischemia/reperfusion (I/R) is a major clinical problem with a high mortality rate and a lack of therapeutic treatment. During I/R, cellular homeostasis is disrupted owing to energy depletion, leading to cell death. Fatty acid β-oxidation is the major metabolic pathway for generating adenosine triphosphate (ATP) in the kidneys, which is governed by carnitine palmitoyltransferase 1 (CPT1). C75 is a synthetic compound that up-regulates CPT1 activity. Thus, we hypothesized that C75 treatment could increase energy production and alleviate renal I/R injury.. We subjected male adult rats to renal I/R by bilateral renal pedicle clamping with microvascular clips for 60 min, followed by administration of 8% dimethyl sulfoxide (vehicle) or C75 (3 mg/kg body weight), with 5 animals/group. We collected blood and renal tissues 24 h after reperfusion and subjected them to various measurements and histological examination.. C75 treatment restored the loss of CPT1 activity and intracellular ATP levels in the kidneys after I/R. Administration of C75 significantly lowered serum creatinine, blood urea nitrogen, aspartate aminotransferase, and lactate dehydrogenase levels elevated by I/R. C75 treatment preserved morphological features of the kidneys with a significant improvement in the damage score. In addition, C75 treatment inhibited the increase of TNF-α levels in serum and kidneys, and lowered myeloperoxidase activity in the kidneys after I/R.. Stimulation of CPT1 activity by C75 recovered ATP depletion, improved renal function, attenuated tissue injury, and inhibited proinflammatory cytokine production and neutrophil infiltration after renal I/R injury. Therefore, enhancing the metabolism pathways for energy production may provide a novel modality to treat renal I/R injury.

Topics: 4-Butyrolactone; Acute Kidney Injury; Adenosine Triphosphate; Animals; Carnitine O-Palmitoyltransferase; Edema; Energy Metabolism; Kidney; Leukocytes; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

ADAMTS13 cleaves hyperactive ultra-large von Willebrand factor (ULVWF) multimers into smaller and less active forms. It remains unknown whether VWF-mediated inflammatory processes play a role in the enhanced brain injury due to ADAMTS13 deficiency.. We tested the hypothesis that the deleterious effect of ADAMTS13 deficiency on ischemic brain injury is mediated through VWF-dependent enhanced vascular inflammation.. Transient focal cerebral ischemia was induced by 60 min of occlusion of the right middle cerebral artery. Myeloperoxidase (MPO) activity and inflammatory cytokines in the infarcted region were evaluated 23 h after reperfusion injury. Neutrophil infiltration within the infarct and surrounding areas was quantitated by immunohistochemistry.. We report that ADAMTS13-deficient mice exhibited significantly enlarged infarct size, concordant with increased myeloperoxidase (MPO) activity, neutrophil infiltration and expression of the pro-inflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). In contrast, VWF-deficient mice exhibited significantly reduced MPO activity, neutrophil infiltration and inflammatory cytokine induction, demonstrating a role of VWF in these inflammatory processes. Mice deficient for both ADAMTS13 and VWF exhibited an identical reduction of the same inflammatory parameters, demonstrating that the increased inflammation observed in ADAMTS13-deficient mice is VWF dependent. Finally, the increased infarct size observed in ADAMTS13-deficient mice was completely abrogated by prior immunodepletion of neutrophils, demonstrating a causal role for acute inflammation in the enhanced brain injury that occurs in the setting of ADAMTS13 deficiency.. These findings provide new evidence for ADAMTS13 in reducing VWF-mediated acute cerebral inflammation following ischemic stroke.

Topics: Acute Disease; ADAMTS13 Protein; Animals; Brain; Disease Models, Animal; Immunohistochemistry; Infarction, Middle Cerebral Artery; Inflammation Mediators; Interleukin-6; Male; Metalloendopeptidases; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophil Infiltration; Peroxidase; Reperfusion Injury; Time Factors; Tumor Necrosis Factor-alpha; Vasculitis, Central Nervous System; von Willebrand Factor

To compare the effects of N-acetylcysteine (NAC) and ethyl pyruvate (EP) on experimental testicular ischemia-reperfusion (I/R) injury.. Randomized, controlled, experimental study.. University hospital.. Twenty-four mature male Wistar rats.. Rats were divided into four groups: control group, torsion-detorsion (T/D) group, EP group, and NAC group. In the pretreatment of the NAC and EP groups, 20 mg/kg NAC and 50 mg/kg EP were given intraperitoneally (IP) 30 minutes before detorsion.. Serum ischemia-modified albumin (IMA), tissue and serum malondialdehyde, and myeloperoxidase activity levels and histopathological damage scores were then compared.. Ethyl pyruvate and N-acetylcysteine exhibited a protective effect against I/R injury. Of the biochemical parameters evaluated as a result of testicular I/R, only IMA levels were significantly elevated. There was a strong and significant correlation between serum IMA levels and histopathological injury scores, and the increase in serum IMA level exhibited a strong parallel with the increase in histopathological injury. In the EP group, although the histopathological injury score was similar to that of the control group, serum IMA levels were significantly elevated.. Both NAC and EP, the effects of which on I/R injury are evaluated in the present study, reduce such injury in testicular torsion-detorsion. Comparing their effects on IMA levels, NAC may be regarded as a relatively more effective treatment than EP.

Topics: Acetylcysteine; Animals; Male; Malondialdehyde; Peroxidase; Pyruvates; Rats; Rats, Wistar; Reactive Oxygen Species; Reperfusion Injury; Serum Albumin; Testis

The aim of the present study was to evaluate the effects of phosphodiesterase type 5 (PDE5) inhibitory drugs, Tadalafil and Sildenafil, on inducible NOS (iNOS), endothelial NOS (eNOS) and p53 genes expressions and apoptosis in ischemia/reperfusion (I/R) induced oxidative injury in rat renal tissue. Eighty Sprague-Dawley rats (300-350 g) were divided into four groups. In ischemia/reperfusion group, rats were subjected to renal ischemia by clamping the left pedicle for 60 min, and then reperfused for 90 min. On the other hand, in other two groups the rats were individually pretreated with Tadalafil and Sildenafil 1 h before the induction of ischemia. Malondialdehyde (MDA) is determined in renal tissue homogenates by high-performance liquid chromatography, the number of apoptotic cell were calculated by TUNEL method and p53 and eNOS expression were detected with immunohistochemistry. On the other hand, myeloperoxidase (MPO) levels were measured by spectrophotometric method and the mRNA level of iNOS in renal tissue was determined by Real-time PCR (RT-PCR). Our results indicate that MDA and MPO levels were increased in the I/R group than those in the control group. Both Tadalafil and Sildenafil treatment decreased the MDA levels in ischemia/reperfusion group, whereas this effect was more potent with Sildenafil. RT-PCR results showed that, iNOS gen expression increased in the I/R group, but decreased in the PDE5 inhibitory drugs treated group. Apoptotic cells, eNOS levels and p53 positive cells were also decreased in PDE5 inhibitory drugs treated group. We suggest that Tadalafil and Sildenafil have beneficial effects against I/R related renal tissue injury and this protective effect is clearer for Sildenafil than Tadalafil.

Topics: Animals; Apoptosis; Carbolines; Gene Expression; Ischemia; Kidney; Male; Malondialdehyde; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Oxidative Stress; Peroxidase; Phosphodiesterase 5 Inhibitors; Piperazines; Purines; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sildenafil Citrate; Sulfones; Tadalafil; Tumor Suppressor Protein p53

Hymenaea stigonocarpa Mart. ex Hayne (Fabaceae) is a medicinal species commonly found in the Brazilian savannah. The stem bark of this medicinal plant, popularly known as "jatobá-do-cerrado", is widely used in tea form to treat gastric pain, ulcers, diarrhoea and inflammation, whereas its fruits pulp is edible.. The aim of this study was to investigate the antidiarrheal and anti-ulcer effects of a methanolic extract derived from the stem bark (MHs) and diet with fruit pulp of H. stigonocarpa.. The antidiarrheal action of MHs was measured against the intestinal motility and diarrhoea induced by castor oil in mice. The preventive action of MHs (50, 100, 150 and 200mg/Kg, by oral route (p.o.)) against peptic ulcers was evaluated in experimental rodent models challenged with absolute ethanol, non-steroidal anti-inflammatory drugs (NSAIDs), ischemia-reperfusion (I/R) (200mg/Kg, p.o.) and cysteamine (200mg/Kg, p.o.). The main anti-ulcer mechanisms of action of MHs were analysed as follows: evaluation of the gastric juice parameters, assessment of mucus adherence to the gastric wall, determination of the role of nitric oxide (NO) and sulfhydryl compounds (SH), glutathione (GSH) levels and myeloperoxidase (MPO) activity. The healing effects from MHs (200mg/Kg) and diet with fruit pulp (10%) against gastric and duodenal ulcers induced by acetic acid were also evaluated by treating rats over 7 or 14 consecutive days of treatment.. The phytochemical profile of MHs and fruit pulp indicated the presence of phenolic compounds (mainly flavonoids and condensed tannins). MHs (200mg/Kg, p.o.) displayed an antidiarrheal effect and were able to protect gastric mucosa against absolute ethanol (68% protection) and also against the injurious effect of NSAIDs (86% protection) when compared to the group treated with vehicle. These results were accompanied by the prevention of GSH depletion and an inhibition of MPO activity when compared to animals treated with vehicle (P<0.05). MHs markedly protected duodenal mucosa against injuries caused by cysteamine (98%) and also against I/R induced gastric ulceration (80%) when compared to the group treated with vehicle. Furthermore, MHs also prevented the GSH depletion of gastric mucosa relative to the control group treated with vehicle. NO appeared to be involved in this gastroprotective effect. MHs and diet with fruit pulp clearly demonstrated gastric healing actions after treatment for 7 (MHs - 53% inhibition) or 14 days (MHs - 60% inhibition and fruit pulp - 61% inhibition). Treatment with diet with fruit pulp for 7 days demonstrates a significant duodenal healing effect (71% inhibition) without any signs of toxicity.. MHs clearly demonstrate antidiarrheal, gastroprotective and cicatrising effects in experimental gastric and duodenal ulcers, and the diet with fruit pulp displays duodenal healing effects. The observed effects may be associated with the antioxidant effect, which may be due the presence of condensed tannins and flavonoids in the bark and fruit of H. stigonocarpa.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Anti-Ulcer Agents; Antidiarrheals; Brazil; Castor Oil; Cysteamine; Diarrhea; Disease Models, Animal; Duodenal Ulcer; Ethanol; Female; Flavonoids; Fruit; Gastric Mucosa; Glutathione; Hymenaea; Intestinal Mucosa; Male; Mice; Mice, Inbred Strains; Nitric Oxide; Peroxidase; Phenols; Phytotherapy; Plant Bark; Plant Extracts; Plant Stems; Plants, Medicinal; Rats; Rats, Wistar; Reperfusion Injury; Stomach Ulcer; Tannins

Ischemia/reperfusion (I/R) injury is associated with systemic inflammatory response. Macrophage migration inhibitory factor (MIF) has been implicated in many inflammatory processes. Tanshinone IIA (TSA) is one of the active ingredients in danshen, which derived from the dried root or rhizome of Salviae miltiorrhizae Bge. Recent studies have demonstrated that TSA has protective effects against focal cerebral I/R injury. However, little is known about the underlying mechanisms. Here we put forward the hypothesis that TSA acts through inhibition of MIF expression during focal cerebral I/R injury in rats.. Rats were subjected to middle cerebral artery occlusion (MCAO) for 2 hours. This was followed by reperfusion. We measured neurological deficits, brain water content, and infarct volume, and found that neurological dysfunction, brain edema, and brain infarction were significantly attenuated by TSA 6 hours after reperfusion. We also measured myeloperoxidase (MPO) activity at 6 and 24 hours, and found that neutrophil infiltration was significantly higher in the vehicle+I/R group than in the TSA+I/R group. ELISA demonstrated that TSA could inhibit MIF expression and the release of TNF-α and IL-6 induced by I/R injury. Western blot analysis and immunofluorescence staining showed that MIF expression was significantly lower in the TSA+I/R group than in the vehicle+I/R group. MIF was found almost all located in neurons and hardly any located in astrocytes in the cerebral cortex. Western blot analysis and EMSA demonstrated that NF-κB expression and activity were significantly increased in the vehicle+I/R group. However, these changes were attenuated by TSA.. Our results suggest that TSA helps alleviate the proinflammatory responses associated with I/R-induced injury and that this neuroprotective effect may occur through down-regulation of MIF expression in neurons.

Topics: Abietanes; Animals; Antigens, Nuclear; Brain Ischemia; Cerebral Infarction; Glial Fibrillary Acidic Protein; Inflammation Mediators; Intramolecular Oxidoreductases; Macrophage Migration-Inhibitory Factors; Male; Nerve Tissue Proteins; Neuroprotective Agents; Neutrophil Infiltration; Peroxidase; Protein Transport; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Time Factors; Transcription Factor RelA; Water

Bilateral lower limb ischemia-reperfusion (I/R) could cause significant oxidative stress, elicit inflammatory response, and subsequently induce kidney injury in animals. We tested the effects of platonin, a potent antioxidant, on mitigating the kidney injury induced by lower limb I/R in rats.. Adult male rats were allocated to receive I/R or I/R plus platonin (100 μg/kg intravenous injection immediately after reperfusion), and denoted as the I/R or the I/R-P group, respectively (n = 10 in each group). Sham groups were run simultaneously. Bilateral lower limb I/R was achieved by applying rubber-band tourniquets high around each thigh for 3 hours, followed by reperfusion for 6 hours. After sacrifice, the level of kidney injury was assayed.. I/R significantly increased the plasma concentrations of blood urea nitrogen (BUN) and creatinine (Cr). However, this effect could be mitigated by platonin, as the plasma concentrations of BUN and Cr of the I/R-P group were significantly lower than those of the I/R group. Moreover, histological findings revealed moderate injury in kidney tissues of the I/R group and mild injury in those of the I/R-P group. In addition, the leukocyte infiltration and myeloperoxidase activity in kidney tissues as well as the renal concentrations of inflammatory molecules (i.e., cyclooxygenase-2/prostaglandin E(2), interleukin-6, and macrophage inflammatory protein-2) and malondialdehyde (i.e., the index of lipid peroxidation) of the I/R group were significantly higher than those of the I/R-P group.. Platonin attenuates kidney injury induced by bilateral lower limb I/R in rats.

Topics: Animals; Blood Pressure; Dinoprostone; Heart Rate; Kidney; Lower Extremity; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Thiazoles

Ischemia-reperfusion (IR) can lead to serious tissue oxidative injury in animals. ShuJinHuoXue tablet (SJHXT) is a Chinese Traditional Medicine which can relax the muscles and stimulate the blood circulation and has been used as a clinical medicine. In the present study, we investigated the effects of SJHXT pretreatment on oxidative injury using an animal model of acute limb IR. Results showed that SJHXT pre-treatment (200, 300 and 400 mg/kg/day) markedly reduced serum endothelin-1 (ET-1), thromboxane B2 (TXB₂) levels and thromboxane B2/6-keto- prostaglandin F1α (TXB₂/6-Keto-PGF(1α)), wet weight/dried weight (W/D) ratio, myeloperoxidase (MPO), creatine kinase (CK), lactate dehydrogenase (LDH) activities, and increased serum nitric oxide (NO), 6-Keto-PGF(1α) levels and NO/ET-1 ratio in the IR+SJHXT groups. In addition, the SJHXT pre-treatment (200, 300 and 400 mg/kg/day) markedly reduced skeletal muscle Ca²⁺, malondialdehyde (MDA) levels, increased Na⁺-K⁺-ATPase, Ca²⁺-Mg²⁺-ATPase, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities. Our results suggest that SJHXT pre-treatment may improve skeletal muscle blood vessel microcirculation, decrease skeletal muscle oxidative injury and enhance antioxidant enzymes activities in IR animals.

Topics: Animals; Ca(2+) Mg(2+)-ATPase; Catalase; Creatine Kinase; Drugs, Chinese Herbal; Endothelin-1; L-Lactate Dehydrogenase; Malondialdehyde; Muscle, Skeletal; Nitric Oxide; Peroxidase; Phytotherapy; Prostaglandins F; Rabbits; Reperfusion Injury; Sodium-Potassium-Exchanging ATPase; Superoxide Dismutase; Tablets; Thromboxane B2

Gastrointestinal methane generation has been demonstrated in various conditions, but it is not known whether it has any impact on the mammalian physiology or pathophysiology. Our aim was to characterize the effects of exogenous methane on the process of inflammatory events induced by reoxygenation in a canine model of ischemia-reperfusion.. Sodium pentobarbital-anesthetized inbred beagle dogs (n = 18) were randomly assigned to sham-operated or ischemia-reperfusion (I/R) groups. I/R was induced by occluding the superior mesenteric artery for 1 h, and the subsequent reperfusion was monitored for 3 h. For 5 min before reperfusion, the animals were mechanically ventilated with normoxic artificial air with or without 2.5% methane. The macrohemodynamics and small intestinal pCO2 gap changes were recorded and tissue superoxide and nitrotyrosine levels and myeloperoxidase activity changes were determined in intestinal biopsy samples. Structural mucosal damage was measured via light microscopy and HE staining.. Methane inhalation positively influenced the macrohemodynamic changes, significantly reduced the intestinal pCO2 gap changes and the magnitude of the tissue damage after reperfusion. Further, the intestinal myeloperoxidase activity, the superoxide and nitrotyrosine levels were reduced.. These data demonstrate the anti-inflammatory profile of methane. The study provides evidence that exogenous methane modulates leukocyte activation and affects key events of I/R-induced oxidative and nitrosative stress.

Topics: Administration, Inhalation; Animals; Anti-Inflammatory Agents; Biomarkers; Carbon Dioxide; Disease Models, Animal; Dogs; Hemodynamics; Inflammation; Intestine, Small; Leukocytes; Methane; Peroxidase; Random Allocation; Reperfusion Injury; Superoxides; Tyrosine

The aim of this study was to evaluate the effects of dexmedetomidine on ischemia-reperfusion injury of epigastric island flaps of rats.. Eighty Wistar rats were divided into 4 groups. After the flap elevation, in group 1, the flaps were sutured back without ischemic insult. Groups 2, 3, and 4 were exposed to ischemia for 12 hours. In groups 1 and 2, saline, in group 3, 10 μg/kg dexmedetomidine, and in group 4, 30 μg/kg dexmedetomidine were administered i.p. 45 minutes before I/R periods. Each group was subdivided further into 2 equal groups (a and b). Tissue samples of groups 1a, 2a, 3a, and 4a were obtained 12 hours after the reperfusion, and those of groups 1b, 2b, 3b, and 4b were obtained after 7 days. The necrotic areas were also calculated. Nitric oxide, malondialdehyde (MDA), and myeloperoxidase (MPO) activity were assessed in the tissue samples.. Nitric oxide, MDA, and MPO activity levels in group 2a were significantly higher those in group 1a (P < 0.05). The levels in groups 3a and 4a were lower than those in group 2a (P < 0.05). Nitric oxide, MDA, and MPO activity levels were significantly higher in group 2b compared with group 1b (P < 0.05). The levels were lower in Groups 3b and 4b compared with group 2b (P < 0.05). Flap necrosis area was significantly lower in groups 3b and 4b than that in group 2b (P < 0.05).. We conclude that administering dexmedetomidine before I/R periods can reduce ischemia-reperfusion injury of flaps, and it has a beneficial effect on flap survival.

Topics: Analysis of Variance; Animals; Dexmedetomidine; Malondialdehyde; Nitric Oxide; Peroxidase; Random Allocation; Rats; Rats, Wistar; Reperfusion Injury; Statistics, Nonparametric; Surgical Flaps

Ghrelin, a 28-amino acid peptide, is mainly secreted by the stomach. Ghrelin has been shown to have neuroprotective effects. However, whether ghrelin protects the spinal cord from ischemia/reperfusion (I/R) injury is unknown. To investigate this, 60 rats were randomly divided into three different groups: the sham group (n = 20), the vehicle group (n = 20), and the Ghrelin group (100 μg/kg, n = 20). Rats were sacrificed 12, 24, 48 and 72 h after ischemia. After the evaluation of neurologic function (48 h), the spinal cords were immediately removed for the determination of myeloperoxidase (MPO) activity (12-72 h). Apoptosis was quantitatively measured using the terminal transferase UTP nick end-labeling (TUNEL) method (24 h). The expression of bax and bcl-2 were evaluated by Western blot analysis (1 h), and GHSR-1a mRNA expression was detected using reverse transcriptase polymerase chain reaction (24 h). The neurological motor function was evaluated by 'Tarlov's score'. The neurologic outcomes in the ghrelin-group were significantly better than those in the vehicle group (p < 0.05). Serum tumor necrosis factor (TNF-α) levels were assessed in the peripheral venous blood. Ghrelin decreased the serum TNF-α levels and ameliorated the down regulation of spinal cord MPO activity. The expression of ghrelin receptors (GHSR-1a) in the rat spinal cord was decreased by I/R injury and increased by ghrelin. Ghrelin reduced the TUNEL-positive rate. Greater bcl-2, HSP27, HSP70, and attenuated bax expression were observed in the ghrelin-treated rats. Our results suggest that ghrelin administration may inhibit spinal I/R injury. Moreover, the improvement of neurologic function in rats was increased after the ghrelin treatment.

Topics: Animals; Apoptosis; Blotting, Western; Enzyme-Linked Immunosorbent Assay; Ghrelin; Male; Neuroprotective Agents; Peroxidase; Rats; Rats, Sprague-Dawley; Real-Time Polymerase Chain Reaction; Receptors, Ghrelin; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Spinal Cord

To investigate the protective effect of infliximab on ischemia-reperfusion (I/R) injury of the rat kidney.. Twenty-eight male Wistar albino rats were divided into four groups: sham-operated, I/R, I/R with infliximab administered before ischemia [I/R + infliximab (bi)], and I/R with infliximab administered before reperfusion [I/R + infliximab (br)]. After a right nephrectomy to produce damage, the left renal vessels were occluded for 60 min, followed by 24-h reperfusion in rats. Changes in the rat kidney were observed by measuring the tissue levels of malondialdehyde (MDA), myeloperoxidase (MPO), glutathione (GSH), and superoxide dismutase (SOD) and by evaluating hematoxylin-eosin (H&E)-stained and periodic acid-Schiff (PAS) sections.. The MDA and MPO levels in the I/R group were significantly higher than in the other groups (p < 0.05), and the SOD and GSH levels in the I/R + infliximab (bi) and I/R + infliximab (br) groups were significantly higher than in the I/R group (p < 0.05). However, histological examination revealed that the I/R + infliximab (bi) group and the I/R + infliximab (br) group had significantly fewer tubular changes and interstitial inflammatory cell infiltration than the I/R group.. These results show that infliximab may protect against I/R injury in the rat I/R model.

Topics: Acute Kidney Injury; Animals; Anti-Inflammatory Agents, Non-Steroidal; Antibodies, Monoclonal; Disease Models, Animal; Infliximab; Kidney; Kidney Tubules; Male; Malondialdehyde; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Tumor Necrosis Factor-alpha

RNA interference targeting RelB can significantly attenuate ischemia/reperfusion (I/R)-induced renal dysfunction, but its roles in liver I/R injury remain to be defined. We have investigated whether siRNA targeting of RelB in liver could also elicit protection against I/R injury.. A RelB miRNA RNAi expression plasmid, a scrambled plasmid, or phosphate-buffered saline (50 μg of the plasmid diluted in phosphate-buffered saline, 8% wt/vol) were rapidly injected, within 6-8 s, into mouse tail veins 24 h before liver I/R. Mice were subjected to 30 min of 70% hepatic ischemia or to a sham operation. Six h after reperfusion, blood and liver tissue samples were collected for subsequent assays.. The expression level of RelB was reduced in the RelB RNAi group compared with the control group, while it was increased in the I/R group. In the sham group, malondialdehyde, myeloperoxidase (MPO), and superoxide dismutase serum levels were almost the same, but the alanine aminotransferase level in the untreated group was 20- to 25-fold lower than in the other groups. In I/R-treated mice, although alanine aminotransferase, malondialdehyde, and MPO serum levels in the RelB RNAi group were lower than in other groups, all were higher than in the sham group. Silencing RelB could inhibit the decrease of superoxide dismutase activity and the upregulation of MPO and tumor necrosis factor α induced by I/R injury.. Silencing RelB can protect the liver against I/R-induced damage. Therefore, it is a promising therapeutic target for protection against I/R injury in the liver.

Topics: Alanine Transaminase; Animals; Liver; Male; Mice; Mice, Inbred C57BL; Peroxidase; Plasmids; Reperfusion Injury; RNA Interference; Transcription Factor RelB; Tumor Necrosis Factor-alpha

Ischemia/reperfusion injury (IRI) is the most common cause of early mortality following lung transplantation (LTx). We hypothesized that nitrite, an endogenous source of nitric oxide (NO), may protect lung grafts from IRI. Rat lung grafts were stored in preservation solution at 4°C for 6 hours. Both grafts and recipients were treated with nitrite. Nitrite treatment was associated with significantly higher levels of tissue oxygenation, lower levels of cytokines and neutrophil/macrophage infiltration, lower myeloperoxidase activity, reduced oxidative injury and increased cGMP levels in grafts than in the controls. Treatment with either a nitric oxide scavenger or a soluble guanylyl cyclase (sGC) inhibitor diminished the beneficial effects of nitrite and decreased cGMP concentrations. These results suggest that nitric oxide, generated from nitrite, is the molecule responsible for the effects of nitrite via the nitric oxide/sGC/cGMP pathway. Allopurinol, a xanthine oxidoreductase (XOR) inhibitor, abrogated the protective effects of nitrite, suggesting that XOR is a key enzyme in the conversion of nitrite to nitric oxide. In vitro experiments demonstrated that nitrite prevented apoptosis in pulmonary endothelial cells. Nitrite also exhibits longer survival rate in recipients than control. In conclusion, nitrite inhibits lung IRI following cold preservation and had higher survival rate in LTx model.

Topics: Acute Lung Injury; Animals; Disease Models, Animal; Graft Rejection; Graft Survival; Lung Transplantation; Male; Nitric Oxide; Nitrites; Oxidative Stress; Peroxidase; Random Allocation; Rats; Rats, Inbred Lew; Rats, Sprague-Dawley; Reference Values; Reperfusion Injury

Ample of evidence proved the gastroprotective effect of thymoquinone (TQ), the main constituent of Nigella sativa oil; however, the full mechanistic cassette on the gastric ulcer etiopathogenesis is not fully elucidated. The aim of the present work is to unveil some of the possible mechanisms. Animals were injected with vehicle, TQ (10 & 20mg/kg), omeprazole (10 & 20mg/kg) or their combination (10mg/kg). Thirty minutes later, pyloric ligation was carried out and followed consequently with ischemia for another 30min, abided by reperfusion for 120min. The ischemia/reperfusion insult increased the gastric acid secretion, acid output, and pepsin, as well as the gastric mucosal content/activity of lipid peroxide, proton pump and myeloperoxidase, along with ulcer index. However, content/activity of gastric mucin, reduced glutathione, total nitric oxide, and superoxide dismutase were decreased. TQ, especially the high dose level, corrected the altered parameters in a comparable manner to that of the reference drug used, omeprazole. In addition, when the low doses were combined they add to each other to reach the effect of the high dose of either drug. These results showed that apart from its known antioxidant properties, TQ has novel gastroprotective mechanisms via inhibiting proton pump, acid secretion and neutrophil infiltration, while enhancing mucin secretion, and nitric oxide production.

Topics: Animals; Anti-Ulcer Agents; Antioxidants; Benzoquinones; Cytoprotection; Disease Models, Animal; Gastric Acid; Gastric Mucins; Gastric Mucosa; Glutathione; H(+)-K(+)-Exchanging ATPase; Lipid Peroxides; Male; Neutrophil Infiltration; Nitric Oxide; Omeprazole; Pepsin A; Peroxidase; Proton Pump Inhibitors; Rats; Rats, Wistar; Reperfusion Injury; Stomach Ulcer; Superoxide Dismutase; Time Factors

Intestinal ischemia-reperfusion (I/R) is a common and serious clinical condition. Lactoferrin (Lf) has displayed antioxidative and anti-inflammatory activities in protecting the intestinal mucosa. The objective of this study was to investigate whether oral administration of Lf could attenuate I/R-induced intestinal injury.. The experimental design consisted of three groups of Wistar rats (24 per group): sham operation, control (I/R, saline), Lf (I/R, Lf). Intestinal I/R was produced by occlusion of the superior mesenteric artery for 45 min. Eight rats from each group were randomly sacrificed 3, 12 or 36 h after reperfusion, and blood and intestinal samples were collected.. Intestinal I/R resulted in gut damage evidenced by morphological alteration, reduction of γ-glutamyl transpeptidase (γ-GGT) activity and increased cell apoptosis. Daily administration of Lf (200 mg/kg) for 14 days before surgery significantly attenuated gut damage by reducing the histologic score and apoptosis index, and restoring intestinal γ-GGT activity. Lf reduced intestinal malondialdehyde and myeloperoxidase, restored glutathione and decreased serum levels of tumor necrosis factor-α, interleukin (IL)-1β and IL-6 compared with saline control in I/R rats. In addition, oral administration of Lf did not produce any significant effects in healthy rats; Lf at doses of 50 or 100 mg/kg also attenuated I/R-induced gut damage, but administration of Lf for 7 days did not exert a significant protective effect against I/R-induced gut damage.. These results indicate that Lf may serve as a potent supplement in protecting the gut from intestinal I/R-induced injury by its antioxidative, anti-inflammatory and antiapoptotic activities.

Topics: Administration, Oral; Animals; Anti-Infective Agents; Apoptosis; gamma-Glutamyltransferase; Glutathione; Interleukin-1beta; Interleukin-6; Intestinal Diseases; Intestine, Small; Lactoferrin; Male; Malondialdehyde; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Tumor Necrosis Factor-alpha

Ischemia/reperfusion (I/R) injury is harmful to the cardiovascular system and is responsible for the inflammatory response and multiple organ dysfunctions. In this study we investigated the effect of activated clotting time level on the aortic cross-clamping triggers a systemic inflammatory response and it effects to lungs and heart.. End organ concentrations of interleukin-6 (IL-6), myeloperoxidase (MPO) and heat shock protein 70 (HSP-70) were determined in four groups of Spraque Dawley rats: ischemic control (operation with cross clamping received IP of 0.9% saline at 2 ml/kg n=7) Sham (operation without cross clamping, n=7), heparin (ACT level about 200), High dose heparin (ACT level up to 600) The infrarenal aorta was clamped for 45 minutes by a mini cross clamp approximately 1cm below the renal artery and 1cm iliac bifurcation in all groups without sham group. Heparin was given intraperitoneal (IP) before the procedure. All rats were sacrificed 48 h later. In a second experiment, the effects of I/R on remote organs (lungs and heart) were harvested for analysis. We evaluated tissue levels of myeloperoxidase, interleukin-6, and heat shock protein (HSP-70) were analyzed as markers oxidative stress and inflammation. Histological analyses of the organs were performed.. The lungs paranchymal MPO and HSP-70 levels significantly decreased (p<0.05), but IL-6 level was not significant (p>0.05) in heparinized and high dose heparinized groups when compared to ischemic control group. Histopathological evaluation as edema, cell degeneration, inflammation statistically significantly decreased in both group heparinized and high dose heparinized compared with ischemic control group (p<0.05). The heart paranchymal MPO levels significantly decreased in heparinized and high dose heparinized groups when compared to ischemic control group (p=0.023). IL-6, HSP-70 levels were not significant heparinized and high dose heparinized groups when compared to ischemic control group (p=0.0489, p=0.0143). Histopathological evaluation as degeneration statistically significantly decreased in both group heparinized and High dose heparinized compared with ischemic control group (p=0.005).. Heparin decreased remote organs injury on the lung and heart after ischemia/reperfusion of infra-renal section of the body in the rat model. So, we should be balance to act level for avoid to I/R injury per operative and early post operative period as providing ACT level nearly 200.

Topics: Animals; Coronary Vessels; Heart; Heparin; HSP70 Heat-Shock Proteins; Immunohistochemistry; Interleukin-6; Lung; Male; Myocardial Reperfusion Injury; Myocardium; Peroxidase; Protective Agents; Rats; Rats, Sprague-Dawley; Reperfusion Injury

We aimed to investigate the effects of caffeic acid phenethyl ester (CAPE) on intestinal mucosal injury induced by superior mesenteric occlusion.. This experimental study was conducted on 48 male Wistar-albino rats. The animals were randomly allocated into four groups: (i) Sham-operated group, laparotomy without intestinal ischemia/reperfusion (IR) injury (n = 12); (ii) Sham + CAPE group, identical to group 1 except for CAPE treatment (10 μmol/kg, intravenously) (n = 12); (iii) Intestinal IR group, 60 min of superior mesenteric ischemia followed by 3 hr of reperfusion (n = 12); and (iv) (IR + CAPE)-treated group, 10 μmol/kg injection of CAPE intravenously 30 min before the reperfusion period (n = 12). We evaluated the degree of intestinal mucosal injury on a grading scale, histopathologically, and by measuring oxidative stress markers and antioxidant parameters, biochemically. Intestinal edema was estimated by using wet/dry weight ratios. The plasma proinflammatory cytokine levels were measured. Animal survival was observed up to one week.. Intestinal mucosal injury scores were significantly decreased with CAPE administration (p < .05). CAPE treatment significantly reduced oxidative stress markers in the intestinal tissues (p < .05) and the plasma proinflammatory cytokine levels (p < .05), and significantly increased antioxidant parameters in the intestinal tissues (p < .05). Intestinal edema was significantly alleviated by CAPE treatment (p < .05). The survival rates of CAPE-treated IR animals were significantly higher than IR-subjected rats (p < .05).. This study clearly showed that CAPE treatment significantly alleviated the intestinal mucosal injury caused by superior mesenteric ischemia/reperfusion. Further clinical studies are required to clarify whether CAPE has a useful role in reperfusion injury during particular surgeries in which IR-induced organ injury occurs.

Topics: Animals; Antioxidants; Caffeic Acids; Cytokines; Glutathione Peroxidase; Intestine, Small; Male; Malondialdehyde; Models, Animal; Nitrates; Oxidative Stress; Peroxidase; Phenylethyl Alcohol; Plant Bark; Plant Extracts; Rats; Rats, Wistar; Regional Blood Flow; Reperfusion Injury; Xanthine Oxidase

Prolonged warm ischemia (WI) occurring in marginal kidney donors together with reperfusion injury determines allograft survival, in which apoptosis and inflammation play crucial roles. There is no single valid biomarker, so far, to assess the degree of kidney donor injury. To define new biomarkers for detecting initial donor ischemic injury, caspase-3, caspase-7, apoptosis, inflammation, HSP70 and renal histological changes were examined in porcine kidneys subjected to 7- 15- 25- or 40-min WI, two-hour cold storage and six-hour hemoreperfusion. Caspase-3 activity was gradually increased by prolonged reperfusion, with a decrease trend against WI time. This result was verified by raised 17 kDa active caspase-3 in postreperfusion kidneys, with elevated 12 kDa active caspase-3 and lowered precursor at seven-minute WI. Active caspase-7 was also doubled by reperfusion with decreased precursor at seven-minute WI, but declined against prolonged WI. Apoptotic cells in tubular and interstitial areas were greatly increased by reperfusion at seven-minute WI, but decreased against prolonged WI. In addition, myeloperoxidase (MPO)+ cells were dramatically increased by reperfusion and presented as a bell-shape against WI time, while HSP70 was significantly increased at 7-min WI, but decreased at 40-min WI after reperfusion. In postreperfusion kidneys, tubular dilation and cell shedding were observed at 7- and 15-min WI, while tubular vacuolation and cell debris were found in tubular lumens at longer WI times. At 40-min WI, early nuclear pyknosis, tubular epithelia detachment and peri-tubular capillary dilation were detected. Furthermore, caspase-3, caspase-7, apoptosis, but not MPO+ cells or HSP70, were correlated with renal function. In conclusion, caspase-3, caspase-7 and apoptosis appear to be better biomarkers than MPO+ cells or HSP70 for assessing warm ischemic injury in donor kidneys. Hemoreperfusion activates caspase-3 and caspase-7, promotes apoptosis of damaged cells in kidneys only with limited WI, which might be beneficial to renal structural re-modeling and functional recovery.

Topics: Animals; Apoptosis; Biomarkers; Caspase 3; Caspase 7; HSP70 Heat-Shock Proteins; Kidney; Models, Biological; Perfusion; Peroxidase; Reperfusion Injury; Swine; Time Factors; Warm Ischemia

Ischemia/reperfusion (I/R) injury is unavoidable in renal transplantation, and represents an additional risk factor for the late renal allograft failure. Our study focused on the effects of ligustrazine on oxidative stress, apoptosis, neutrophils recruitment, the expression of proinflammatory mediators and adhesion molecules caused by renal I/R injury.. Renal warm I/R was induced in male C57BL/6 mice by clamping the left renal artery and vein non-traumatically. Group I was sham-operated animals; group II, nontreated animals; and group III, ligustrazine-treated animals (80 mg/kg, i.p. 30 min before I/R). Mice were sacrificed 4 and 24h post reperfusion. The effects of ligustrazine on oxidative stress, neutrophils recruitment, proinflammatory mediators, and adhesion molecules caused by renal I/R injury were assayed.. Ligustrazine pretreatment attenuated dramatically the injuries in mice kidneys caused by warm I/R (histological scores of untreated versus treated, 4.2 ± 0.4 versus 0.9 ± 0.3; P<0.01). Administration of ligustrazine significantly reduced myeloperoxidase (MPO) activity by 38.6% and decreased malondialdehye (MDA) level by 19.2%, while superoxide dismutase (SOD) activity increased by 39.6% (P<0.01), suggesting an effective reduction of oxidative stress following ligustrazine treatment. Moreover, ligustrazine also inhibited cell apoptosis, abrogated neutrophils recruitment, and suppressed the over expression of TNF-α and ICAM-1.. In conclusion, ligustrazine protects murine kidney from warm ischemia/reperfusion injury, probably via reducing oxidative stress, inhibiting cell apoptosis, decreasing neutrophils infiltration, and suppressing the overexpression of TNF-α and ICAM-1 levels.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Apoptosis; Disease Models, Animal; Gene Expression; Intercellular Adhesion Molecule-1; Kidney; Kidney Diseases; Kidney Transplantation; Male; Malondialdehyde; Mice; Mice, Inbred C57BL; Neutrophils; Oxidative Stress; Peroxidase; Pyrazines; Reperfusion Injury; Superoxide Dismutase; Tumor Necrosis Factor-alpha

Inflammatory events triggered by the mediators released from free oxygen radicals and infiltrated leukocytes play a direct role in formation of the ischemia-reperfusion (IR) injury. The aim of this study was to investigate the impact of lidocaine on IR injury due to its anti-inflammatory properties.. Following delivery of lidocaine to the ischemic flaps in two different doses prior to the reperfusion, flap survival, malondialdehyde (MDA) level, myeloperoxidase (MPO) level, neutrophil count, and measurement of vascular diameters were studied. Twelve hours after reperfusion, tissue specimens were collected for measurement of MDA level, MPO level, neutrophil count, and vascular diameters. Flap survival was evaluated on the fifth day.. Flap survival rate was 15.54% ± 8.23% in the control group, whereas the groups treated wtih lidocaine showed remarkable elevations in survival rates as follows: 70.83% ± 33.53% and 67.42% ± 30.81%, respectively. MDA levels in sham and lidocaine treatment groups were significantly lower than those observed in control group.. Lidocaine inhibited the increase in MDA level associated with IR injury while showing no influence over increases in number of neutrophils and tissue MPO level, and it elevated the flap survival rate.

Topics: Animals; Anti-Inflammatory Agents; Dose-Response Relationship, Drug; Lidocaine; Malondialdehyde; Models, Animal; Necrosis; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Surgical Flaps

Glutamine (Gln) is the most abundant amino acid in blood and tissue fluids and is considered to be essential in certain catabolic conditions. A series of studies has shown that glutamine can attenuate cytokine release, reduce organ damage and improve survival in a rat model of endotoxaemia. The hypothesis for this rat model study is that pre-treatment with Gln reduces the expression of ICAM-1 and attenuates lung injury induced by intestinal ischaemia-reperfusion (I/R).. Sprague-Dawley rats were randomised into five groups, namely sham group (sham surgery), Gln groups (three different doses) and control group. Lung injury caused by intestinal I/R was evaluated using Evans blue dye concentration and histopathologic examination. The level of myeloperoxidase (MPO) was measured using biochemistry method. The expression of heat shock protein 70 (HSP 70) and ICAM-1 were detected using Western blot and real-time polymerase chain reaction (PCR) methods, respectively.. Compared with the control group, rats pre-treated with Gln before intestinal I/R demonstrated decreased Evans Blue content and MPO activities in lung tissue, reduced the expression of ICAM-1, attenuated lung injury evidenced by pathological change compared with lactated Ringer pre-treated rats. Gln administration increased HSP 70 mRNA and protein expression in lung tissue compared with control group.. Ischaemia-reperfusion injury increases the expression of ICAM-1 in the lung. This may contribute to the migration, accumulation and activation of neutrophils. Pre-treatment with Gln attenuates rat lung injury and reduces ICAM-1 expression.

Topics: Animals; Evans Blue; Glutamine; HSP70 Heat-Shock Proteins; Intercellular Adhesion Molecule-1; Lung Injury; Male; Neutrophils; Peroxidase; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Temporary ligation, primary anastomosis, and temporary shunt have been reported to deal with superior mesenteric artery (SMA) injuries. We aimed to investigate which brought minimal ischemia reperfusion injury in a hypothermic traumatic shock swine model.. SMA was completely clamped while pigs were hemorrhaged to a mean arterial pressure (MAP) of 40 mm Hg. Animals were then randomized into temporary ligation (A, n=8), primary anastomosis (B, n=8), temporary shunt (C, n=8), and control groups (n=4). Animals in group A remained SMA interrupted for additional 1h while the other groups underwent the corresponding procedures immediately. Intestine injury was assessed by histologic examination and measurement of lipid peroxidations at the end of ischemia and experiment.. Overall mortality rate was 50%, 25%, and 0% in groups A, B, and C, respectively (P<0.05). The total intestine ischemia time was predominantly shorter in group C in the other groups. Remarkable elevations of malonaldehyde (MDA) in small intestine were noted after reperfusion in group A. Animals in other groups, however, did not exacerbate during the 6-h reperfusion (resuscitation period). Group C showed the lowest MDA level at the end of experiment. Myeloperoxidase (MPO) levels showed no significant elevations during the ischemia or early reperfusion period; nevertheless, it reached approximately 3- to 6-fold in groups A and B (compared with baseline, P<0.01), and remained unchanged in group C at the end of experiment.. Our study suggests that temporary shunt insertion might be preferred as it shortens ischemia time, alleviates intestinal ischemia/reperfusion injury, and thus decreases early mortality in this animal model.

Topics: Anastomosis, Surgical; Animals; Blood Pressure; Female; Hemodynamics; Ileum; Ischemia; Ligation; Malondialdehyde; Mesenteric Artery, Superior; Mesenteric Ischemia; Models, Animal; Peroxidase; Reperfusion Injury; Shock, Traumatic; Surgical Procedures, Operative; Swine; Vascular Diseases

C-reactive protein (CRP) is an acute pro-inflammatory mediator that has been demonstrated to enhance ischemia/reperfusion (IR) injury by virtue of activating the complement system. CRP is able to interact with complement proteins such as C1q, complement factor H, and C4b-binding protein. Since complement activation is central in the expression of tissue injury following IR, we have investigated the effects of human decay-accelerating factor (DAF), a complement inhibitor, on CRP-potentiated complement activation and tissue injury in mice subjected to mesenteric IR.. Male C57B1/6 mice were allocated into eight groups: (1) Sham-operated group without IR injury; (2) CRP+Sham group; (3) IR group; (4) CRP+IR group; (5) DAF group; (6) CRP+DAF group; (7) IR+DAF group, and (8) CRP+IR+DAF group. Intestinal and lung injury, neutrophil infiltration, myeloperoxidase (MPO) expression, complement component deposition, and interleukin-6 (IL-6) production were assessed for each treatment group of mice.. We report that administration of DAF significantly attenuates the CRP-enhanced intestinal injury as well as remote lung damages following acute mesenteric IR in mice, while DAF inhibits complement activation, suppresses neutrophil infiltration, and reduces IL-6 production.. Our study suggests that inhibition complement activation with DAF may prove useful for the treatment of post-ischemic inflammatory injuries associated with an increased production of CRP.

Topics: Animals; C-Reactive Protein; CD55 Antigens; Complement C5a; Complement Membrane Attack Complex; Injections, Intravenous; Interleukin-6; Male; Mesentery; Mice; Mice, Inbred C57BL; Models, Animal; Neutrophil Infiltration; Peroxidase; Reperfusion Injury

Post-cardiopulmonary bypass (CPB) lung injury is the combination of whole body inflammatory response and local ischemia-reperfusion (IR) injury. We investigated the benefit of pulmonary perfusion with L-arginine in protection against post-CPB lung injury.. New Zealand white rabbits (n = 50, weight, 2.5-2.8 kg) were divided into five groups (n = 10 each): sham (sham sternotomy), CPB (CPB without pulmonary perfusion), perfusion (CPB with pulmonary perfusion), L-arginine (CPB with perfusion + L-arginine), and L-NAME (CPB with perfusion + L-NAME). The duration of CPB was 60 min followed by 2 h of reperfusion. Pulmonary perfusion was performed every 20 min through the pulmonary artery during CPB. Checking parameters included: (1) pulmonary vascular resistance, (2) pulmonary artery endothelium relaxation (organ chamber study), and (3) IR marker (myeloperoxidase) and inflammatory markers (TNF-α, IL-B, NF-κB).. CPB induced pulmonary artery endothelium dysfunction manifested by increased pulmonary vascular resistance and impaired pulmonary artery relaxation. Pulmonary perfusion could significantly reverse the phenomenon (P < 0.01) while provision of NO precursor-L-arginine with pulmonary perfusion together further possessed significant relaxation ability for pulmonary arterial endothelium compared with perfusion alone (P < 0.05). Accordingly, lung parenchyma myeloperoxidase activity and inflammatory cytokine level were also markedly increased after CPB (P < 0.05). Pulmonary perfusion could partially decrease the response, whereas additional L-arginine further attenuated inflammatory cytokine release (P < 0.05).. Pulmonary perfusion during CPB partially ameliorates CPB-induced lung injury. Pulmonary perfusion with L-arginine could further attenuate lung injury by restoring endothelial function and decreasing inflammatory response.

Topics: Acute Lung Injury; Animals; Arginine; Cardiopulmonary Bypass; Interleukin-1beta; Lung; Models, Animal; NF-kappa B; Perfusion; Peroxidase; Pulmonary Artery; Rabbits; Reperfusion Injury; Treatment Outcome; Tumor Necrosis Factor-alpha; Vascular Resistance; Vasodilation

Intestinal ischemia-reperfusion is a common medical event associated with both clinical and experimental distant organ injury. In particular, the lung tissue appears to be susceptible to injury resulting from systemic inflammatory mediator activation. Drotrecogin α (activated) or recombinant human activated protein C has antithrombotic, anti-inflammatory, and profibrinolytic properties. We hypothesized that APC infusion would decrease lung inflammation and ameliorate lung injury resulting from intestinal ischemia-reperfusion (IIR). A rat model of intestinal ischemia-reperfusion was used to test this hypothesis, and several parameters of lung injury were measured in lung samples.. Forty Wistar albino rats were divided into four groups: a sham-operated group (Sham), an ischemic control group (IIR), an APC-infusion group (IIR'APC), and a normal saline-infusion group (IIR'NS) (n = 10, each). A marker for lipid peroxidation, malondialdehyde (MDA), free radical scavenger glutathione peroxidase (GSH-Px), an index of polymorphonuclear neutrophils, myeloperoxidase (MPO) activity, and lung polymorphonuclear leukocytes (PMNL) were investigated in the lung tissue samples.. MDA and MPO levels, and lung PMNL sequestration were decreased, but GSH-Px levels were increased in APC treated group versus IIR group. MDA levels were decreased and GSH-Px levels were increased in NS treated group versus IIR group. MPO levels and lung PMNL counts were similar across the IIR and IIR'NS groups.. This study documents that APC attenuates acute lung injury in intestinal ischemia-reperfusion. NS infusion had also some favorable effects regarding MDA and MPO.

Topics: Acute Lung Injury; Animals; Anti-Inflammatory Agents; Dose-Response Relationship, Drug; Glutathione Peroxidase; Infusions, Intravenous; Intestines; Male; Malondialdehyde; Models, Animal; Neutrophils; Peroxidase; Protein C; Rats; Rats, Wistar; Reperfusion Injury; Sodium Chloride; Treatment Outcome

Hepatic ischemia/reperfusion (IR) has been extensively studied, but reperfusion after acute hepatic congestion caused by venous occlusion is poorly understood. Congestion/reperfusion (CR) is not uncommon with the development of partial liver transplantation and liver resection. The purpose of this study was to compare the impairments caused by acute hepatic CR or IR using a murine model.. Mice were randomly divided into IR, CR, and a sham operation (SO) group. The portal vein and hepatic artery of the left anterior hepatic lobe (LAHL) were clamped in the IR group, while the hepatic vein of the LAHL was temporarily occluded in the CR Group. This occurred for 75 min followed by reperfusion. The animals were sacrificed at 2, 6, and 24h after reperfusion. Blood and liver samples were collected for hepatic function, histology, myeloperoxidase (MPO), intravital microscopy, and real-time PCR analysis.. Both IR and CR groups showed elevated liver function, histologic damage, cellular apoptosis, and microcirculatory dysfunction compared with the SO group. Compared with the IR group, the CR group revealed higher hepatic enzyme activities (ALT: 838.5 ± 155.6 versus 474.6 ± 123.8 P<0.05, AST: 792.5 ± 93.5 versus 574.8 ± 188.4 P<0.05), increased sinusoidal nonperfusion rate at 2h after reperfusion (27.4% ± 1.97% versus 23.8% ± 1.93%, P<0.05), and raised MPO level at 24h (0.34 ± 0.11 versus 0.15 ± 0.04, P<0.01). The mRNA levels of IL-1β at 6h and MCP-1 at 2 and 6h were markedly higher in the CR group than in the IR group.. Hepatic reperfusion after acute congestion provokes an increased inflammatory response and causes more severe impairments in the liver compared with ischemia/reperfusion in a murine model.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Constriction; Hepatic Veins; Ischemia; Liver; Male; Mice; Mice, Inbred C57BL; Models, Animal; Peroxidase; Portal Vein; Prevalence; Reperfusion Injury; Trauma Severity Indices

Several lines of evidence suggest a strong protective potential of pyruvate against ischemia-reperfusion injury. Here, we studied the effect of pyruvate infusion on injury of the small intestine and on systemic parameters in a rat model of severe mesenteric ischemia-reperfusion injury.. Mesenteric ischemia-reperfusion was induced by occlusion/reopening of the superior mesenteric artery of male Wistar rats (90 min ischemia, 120 min reperfusion). Sodium pyruvate was infused at overall doses of 50, 250, and 1,000 mg/kg during two time windows: 30 min before until the induction of ischemia and 30 min before reperfusion until 60 min after beginning of reperfusion.. Pyruvate infusion attenuated ischemia-reperfusion injury of the small intestine between 25% and 55% as indicated by macroscopic and microscopic evaluation, intestinal hemorrhages, and myeloperoxidase activity (neutrophil invasion). There were no significant differences in the local protective effects exerted by the three doses of sodium pyruvate applied. At 250 mg sodium pyruvate/kg and 1,000 mg sodium pyruvate/kg, however, blood pH values were less acidotic, and at 250 mg sodium pyruvate/kg the mean arterial blood pressure remained at higher values during the reperfusion phase. A significant increase in the blood plasma sodium concentration only occurred at 1,000 mg sodium pyruvate/kg.. Pyruvate infusion clearly protects the small intestine against ischemia-reperfusion injury. Protection can already be achieved at doses where sodium overload is negligible. Protection primarily results from local effects on the small intestine. Only at a dose of 250 mg sodium pyruvate/kg and above, systemic effects may additionally contribute.

Topics: Animals; Blood Pressure; Dose-Response Relationship, Drug; Hydrogen-Ion Concentration; Infusions, Intra-Arterial; Intestines; Lactates; Male; Mesentery; Models, Animal; Peroxidase; Pyruvic Acid; Rats; Rats, Wistar; Reperfusion Injury; Severity of Illness Index; Sodium

The aim of this study was to investigate the effect of ischaemic post-conditioning (IPostC) against ischaemia-reperfusion (IR) injury on bilateral testes after unilateral testicular ischaemia in the rat. Eight-week-old male Sprague-Dawley rats were divided into control group; IR group (60 min ischaemia-24 h reperfusion); IPostC1 × 10 group (60 min ischaemia followed by one cycle of 10 sec reperfusion-10 sec ischaemia; then 24 h reperfusion); IPostC3 × 10 group (three cycles of 10 sec reperfusion-10 sec ischaemia; then 24 h reperfusion); IPostC5 × 10 group (five cycles of 10 sec reperfusion-10 sec ischaemia; then 24 h reperfusion) and IPostC3 × 30 group (three cycles of 30 sec reperfusion-30 sec ischaemia; then 24 h reperfusion). In the IR and IPostC groups, the right testicular vessels were clamped using a special vascular clip. Malondialdehyde (MDA) and myeloperoxidase (MPO) levels were measured in testicular tissue samples bilaterally. Additionally, bilateral testicular tissue samples were processed for histological evaluation including haematoxylin-eosin, 4-hydroxy-2-nonenal (4-HNE) and TdT-mediated dUTP Nick End Labelling (TUNEL) staining. The levels of MDA and MPO as well as the positive cells per seminiferous tubule in TUNEL and 4-HNE stain in bilateral testes from the IR group were significantly higher compared with the control group. IPostC3 × 30 protocol significantly ameliorated the aforesaid parameters in both testes compared with the IR group. For the first time, we have demonstrated that IPostC protects both testes after unilateral testicular ischaemia-reperfusion. IPostC3 × 30 protocol offered the most effective protection.

Topics: Animals; Infertility, Male; Ischemic Postconditioning; Male; Malondialdehyde; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Reperfusion Injury; Spermatic Cord Torsion; Testis

Copper deficiency can cause a host of major cardiovascular complications including an augmented inflammatory response through effects on both neutrophils and the microvascular endothelium. In the present study, we evaluated the effect of marginal copper deficiency on the neutrophilic response to hepatic ischemia/reperfusion injury, a condition that induces an inflammatory response. Male weanling Sprague-Dawley rats were fed purified diets which were either copper-adequate (6.3 mg/kg) or copper-marginal (1.62 mg/kg) for 4 weeks prior to undergoing 90 min of partial hepatic ischemia followed by 8 h of reperfusion. Liver injury was assessed by serum levels of alanine aminotransferase and by liver histology. Liver neutrophil accumulation was determined by tissue myeloperoxidase content. There was no significant difference in liver injury between copper-adequate and copper-marginal rats. However, liver neutrophil accumulation was significantly increased in copper-marginal rats. These findings were confirmed histologically. Liver expression of the adhesion molecule, intercellular adhesion molecule-1 (ICAM-1), was increased in copper-marginal rats compared to copper-adequate rats. The results suggest that neutrophil accumulation is increased through enhanced ICAM-1 expression in liver of copper-marginal rats after ischemia/reperfusion, but that this does not result in increased liver injury.

Topics: Alanine Transaminase; Animals; Copper; Intercellular Adhesion Molecule-1; Liver; Male; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

To investigate the effect of a neutrophil elastase inhibitor, sivelestat sodium hydrate, on testicular ischaemia-reperfusion (IR)-injury.. Eight-week-old male Sprague-Dawley rats were divided into four groups: sham-operated control rats; IR rats (group IR); and IR rats that received intra-abdominal administration of 15 mg/kg or 60 mg/kg sivelestat (group IR15 and group IR60, respectively). Right testicular vessels were clamped for 90 min in groups IR, IR15 and IR60. Sivelestat had been administered 45 min after the induction of the ischaemia in groups IR15 and IR60. In subpopulations of IR, IR15 and IR60 rats, reperfusion was performed after ischaemia for 2 h (groups IR-A, IR15-A and IR60-A, respectively) or 48 h (groups IR-B, IR15-B and IR60-B, respectively). At the end of the reperfusion period, blood samples were aspirated from both spermatic veins of each rat and testosterone was evaluated. Then both testes from all rats were collected and tissue levels of malondialdehyde (MDA), myeloperoxidase (MPO), and heat-shock protein-70(HSP-70) were evaluated. Testicular tissue samples were also processed for histological evaluation and TUNEL staining.. MDA, MPO and HSP-70 levels in the ischemic testis were significantly higher in the IR group compared with the control group. MDA and HSP-70 in the contralateral testis were significantly higher in the IR group compared with the control group. Bilateral testosterone levels were lower in all rat groups in comparison with the control group. Bilateral testicular samples in group IR showed extensive histopathologic degenerative alterations and increased percentage of apoptotic cells. Sivelestat treatment lowered the MDA concentration and the percentage of apoptotic cells bilaterally and ameliorated the testicular histological pattern bilaterally.. Unilateral testicular ischaemia causes significant contralateral testicular damage. Sivelestat may be a novel adjunct tool for reducing oxidative stress and partially preventing bilateral testicular damage.

Topics: Animals; Glycine; HSP70 Heat-Shock Proteins; Male; Peroxidase; Proteinase Inhibitory Proteins, Secretory; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sulfonamides; Testis; Testosterone

Glutamine has been used to treat a number of diseases via modulating the inflammatory response. The purpose of this study is to investigate whether glutamine has a beneficial effect in ischemia-reperfusion (IR) induced acute lung injury in an isolated rat lung model. Typical acute lung injury in rats was successfully induced by 60 min of ischemia and 60 min of reperfusion. At the end of experiment, bronchoalveolar lavage fluid (BALF), perfusate and lung tissues were collected to evaluate the degree of lung injury. Glutamine (20 mM) was administrated before ischemia or after ischemia. IR caused a significant increase in the capillary filtration coefficient; lung weight gain; lung weight to body weight ratio; wet to dry weight ratio; pulmonary arterial pressure; and protein concentration and lactate dehydrogenase level in BALF. Tumor necrosis factor-α and cytokine induced neutrophil chemoattractant-1 in perfusate, and malondialdehyde levels, carbonyl content and myeloperoxidase activities in lung tissue were also significantly increased. In addition, the lung tissues showed increased septal thickness and neutrophil infiltration. Furthermore, NF-κB activity and degradation of IκB-α were significantly increased in the lungs. Treatment with glutamine before ischemia or after ischemia significantly decreased the increase in these parameters. Our study showed that glutamine treatment decreased IR-induced acute lung injury. The protective mechanism may be due to the inhibition of NF-κB activation and the attenuation of oxidative stress.

Topics: Acute Lung Injury; Animals; Glutamine; Lung; Male; NF-kappa B; Organ Size; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

Neutrophil infiltration of tissues as part of the inflammatory response to cardiac surgery is one of the major mediators of postoperative multiple-organ dysfunction. Omega-3 fatty acids markedly attenuate endothelial cell inflammatory responses, including upregulation of neutrophil adhesion molecules. The efficacy of a clinically safe form of omega-3 to produce this effect in vivo was examined.. Rat gut intravital microscopic analysis was used to visualize neutrophil transmigration from the microcirculation into the tissues of the gut. Inflammatory activation was in the form of 30 minutes of ischemia and 90 minutes of reperfusion. Sham, control (0.9% saline infusion over 4 hours), and omega-3 (Omegaven [Fresenius Kabi, Bad Homburg, Germany] infusion over 4 hours) pretreatments were compared.. Ischemia-reperfusion resulted in a 4-fold increase in neutrophil adherence to the endothelium (baseline: 4.3 ± 0.2 vs control group: 19.2 ± 3.5 adherent neutrophils per 100 μm, P < .01), which intravenous omega-3 suppressed (7.8 ± 1.7 adherent neutrophils per 100 μm, P < .01). Omega-3 pretreatment also reduced neutrophil transmigration into the tissues after reperfusion (sham group: 6.3 ± 0.8 vs control group: 13.2 ± 1.4 vs omega-3 group: 9.4 ± 0.9 neutrophils per field, P = .037). Gut tissue levels of the neutrophil-released enzyme myeloperoxidase were similarly markedly reduced with omega-3 pretreatment (sham group: 10.5 ± 1.6 vs control group: 19.0 ± 3.3 vs omega-3 group: 10.1 ± 1.2 U/g, P = .03).. Four hours' pretreatment with a relatively safe form of intravenous omega-3 suppressed neutrophil adherence and tissue infiltration, resulting in lower levels of the tissue-damaging enzyme myeloperoxidase. This suggests a possible strategy for diminishing postoperative multiple-organ dysfunction.

Topics: Animals; Anti-Inflammatory Agents; Cardiac Surgical Procedures; Cell Adhesion; Endothelium, Vascular; Fatty Acids, Omega-3; Immunity, Innate; Infusions, Intravenous; Intestines; Leukocyte Rolling; Male; Microscopy, Video; Neutrophil Activation; Neutrophil Infiltration; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Time Factors

This study was designed to investigate the possible effect of sitagliptin on renal damage induced by renal ischemia reperfusion (I/R) in diabetic rats. T2DM in rats was induced by the administration of nicotinamide (230 mg/kg, i.p.), 15 min prior to a single dose of streptozotocin (65 mg/kg, i.v.). In vivo renal I/R was performed in both T2DM and normal rats. Each protocol comprised ischemia for 30 min followed by reperfusion for 24h and a treatment period of 14 days before induction of ischemia. Sitagliptin treated diabetic rats that underwent renal I/R demonstrated significant decrease in the serum concentrations of aspartate aminotransferase (p < 0.01), urea nitrogen (p < 0.01) and creatinine (p < 0.001) compared to renal I/R in diabetic rats. Lipid peroxidation, xanthine oxidase activity, myeloperoxidase activity and nitric oxide level in renal tissue were significantly (p < 0.05, p < 0.001, p < 0.01, p < 0.05 respectively) decreased after renal I/R in sitagliptin treated rats compared to diabetic rats. Antioxidant enzymes like glutathione (p < 0.05), glutathione peroxidase (p < 0.001), superoxide dismutase (p < 0.05) and catalase (p < 0.001) were significantly increased after renal I/R in sitagliptin treated diabetic rats compared to non treated diabetic rats. The typical DNA laddering was observed when renal I/R performed in diabetic rats, which indicates cell apoptosis. Sitagliptin treated rats demonstrated a decrease in DNA fragmentation and apoptosis. Furthermore, renal histopathology preserved in sitagliptin treated rats verified protection against renal I/R in diabetes. The results of present investigation established sitagliptin treatment attenuated renal damage induced by renal I/R in diabetic rats.

Topics: Animals; Apoptosis; Catalase; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; DNA Fragmentation; Female; Glutathione; Glutathione Peroxidase; Kidney; Kidney Diseases; Lipid Peroxidation; Male; Oxidative Stress; Peroxidase; Pyrazines; Rats; Rats, Wistar; Reperfusion Injury; Sitagliptin Phosphate; Superoxide Dismutase; Triazoles; Xanthine Oxidase

Repetitive enteral or intraperitoneal administration of resveratrol at high doses has recently been found to protect the small intestine against acute ischemia/reperfusion (I/R) injury. In the present work, the protective potential of solvent-free continuous intravenous infusions of small amounts of resveratrol was studied in a model of severe intestinal I/R injury.. Mesenteric ischemia was induced in male Wistar rats (six animals/group) by superior mesenteric artery occlusion (SMAO, 90 min) and reperfusion (120 min) by reopening of the microvascular clamp. Resveratrol (0.056 or 0.28 mg/kg) was continuously perfused into the jugular vein (0.014 or 0.07 mg/kg × h) starting 30 min before SMAO; an SMAO control group and sham groups (no SMAO) receiving either 0.9% NaCl solution or resveratrol (0.28 mg/kg) were included. During the experimental procedure, isotonic saline was given at a systolic blood pressure below 90 mmHg, and several parameters including those of biomonitoring and blood gas analysis were measured. Small intestine injury was assessed macroscopically, from released plasma enzyme activities, from the tissue contents of thiobarbituric acid-reactive substances and hemoglobin, from the tissue myeloperoxidase activity, and histopathologically.. Resveratrol at only 0.056 mg/kg significantly decreased the macroscopic damage score, the tissue myeloperoxidase activity, the hemoglobin content, the histopathologic score, and the plasma glutamate-pyruvate transaminase activity, but it did not improve the systemic and metabolic parameters. Instead, during reperfusion, significantly higher volumes of saline were administered to animals receiving the polyphenol, although resveratrol did not significantly affect any parameters in sham-operated animals.. Low doses of intravenously administered resveratrol considerably protected the rat small intestine against severe I/R injury, despite some adverse effects on blood pressure under these conditions.

Topics: Animals; Antioxidants; Blood Pressure; Dose-Response Relationship, Drug; Infusions, Intravenous; Intestine, Small; Male; Models, Animal; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Resveratrol; Severity of Illness Index; Stilbenes

Lower limb ischemia-reperfusion (I/R) imposes oxidative stress, elicits inflammatory response, and subsequently induces acute lung injury. Ischemic preconditioning (IP), a process of transient I/R, mitigates the acute lung injury induced by I/R. We sought to elucidate whether the protective effects of IP involve heme oxygenase-1 (HO-1).. Adult male rats were randomized to receive I/R, I/R plus IP, I/R plus IP plus the HO-1 inhibitor tin protoporphyrin (SnPP) (n = 12 in each group). Control groups were run simultaneously. I/R was induced by applying rubber band tourniquet high around each thigh for 3 h followed by reperfusion for 3 h. To achieve IP, three cycles of bilateral lower limb I/R (i.e., ischemia for 10 min followed by reperfusion for 10 min) were performed. IP was performed immediately before I/R. After sacrifice, degree of lung injury was determined.. Histologic findings, together with assays of leukocyte infiltration (polymorphonuclear leukocytes/alveoli ratio and myeloperoxidase activity) and lung water content (wet/dry weight ratio), confirmed that I/R induced acute lung injury. I/R also caused significant inflammatory response (increases in chemokine, cytokine, and prostaglandin E(2) concentrations), imposed significant oxidative stress (increases in nitric oxide and malondialdehyde concentrations), and up-regulated HO-1 expression in lung tissues. IP significantly enhanced HO-1 up-regulation and, in turn, mitigated oxidative stress, inflammatory response, and acute lung injury induced by I/R. In addition, the protective effects of IP were counteracted by SnPP.. The protective effects of IP on mitigating acute lung injury induced by lower limb I/R are mediated by HO-1.

Topics: Acute Lung Injury; Animals; Enzyme Inhibitors; Heme Oxygenase-1; Ischemic Preconditioning; Leukocytes; Lower Extremity; Male; Malondialdehyde; Metalloporphyrins; Models, Animal; Oxidative Stress; Peroxidase; Protoporphyrins; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Either estrogen or hypertonic saline (HTS) administration can decrease lung inflammation after ischemia-reperfusion. The present study investigated whether combined treatment with estrogen and HTS could provide further protection from mesenteric ischemia-reperfusion (MSIR) injury. Male C3H/HeOuJ mice were randomly segregated into the following groups: sham-operated (sham), vehicle treatment followed by MSIR (vehicle treated), estrogen treatment followed by MSIR (estrogen treated), HTS treatment and MSIR (HTS treated), and combined treatment of estrogen plus HTS and MSIR (combined treated). In MSIR, mice were subjected to mesenteric ischemia for 60 min followed by reperfusion for 30 min. The histology of the lung and the gut was obtained. Lung injury was evaluated by lung edema and myeloperoxidase (MPO) activity; lung protein expression of macrophage migration inhibitory factor (MIF), toll-like receptor-4 (TLR4), phosphorylated inhibitory κBα (p-IκBα), and inducible nitric oxide synthetase (iNOS) were assayed. Survival analysis was monitored after MSIR for 120 min. Compared with those in the sham-treated group, the lung water ratio, MPO activity, and expressions of MIF, TLR4, p-IκBα, and iNOS were significantly increased in the vehicle-treated group. Diminished MIF, TLR4, p-IκBα, and iNOS expressions were found in the estrogen-treated group, whereas suppression of p-IκBα and iNOS was found in the HTS-treated group. Treatment with estrogen or HTS decreased the lung water and MPO activity. The combined treatment of estrogen and HTS further significantly diminished p-IκBα and iNOS expression, lung edema, and MPO activity and improved the inflammation of the lung and the morphology of the gut in histology compared with the results of a single treatment of estrogen or HTS. Survival analysis showed significantly increased survival in the combination-treated group compared with survival in the HTS-treated group. In conclusion, compared with single-agent use, treatment combining estrogen and HTS further decreases lung p-IκBα and iNOS expressions, as well as the degree of lung injury. These effects may result in better rates of survival from MSIR injury.

Topics: Animals; Blotting, Western; Chemotactic Factors; Estrogens; Lung; Male; Mice; Nitric Oxide Synthase Type II; Peroxidase; Reperfusion Injury; Saline Solution, Hypertonic; Toll-Like Receptor 4

Protective effects of ischemic preconditioning in rat small intestine have been shown to be related to the release of calcitonin gene-related peptide.. The purpose of the present study was to explore whether monophosphoryl lipid A participated in the protective process of the delayed ischemic preconditioning in the peripheral vascular bed (the anse intestinalis of rat), and whether endogenous calcitonin gene-related peptide is a mediator in this process.. Intestinal ischemia was induced by occlusion of the superior mesenteric artery for 30 min, followed by reperfusion for 60 min. The intestinal lesions were evaluated by the measurement of serum lactate dehydrogenase, myeloperoxidase levels, and small intestine tissue contents of malondialdehyde. In addition, calcitonin gene-related peptide in plasma and superior mesenteric vein effluent were also examined.. Pretreatment with monophosphoryl lipid A (500 μg/kg. i.p.) 24 h prior to ischemia-reperfusion significantly alleviated the intestinal tissue histology lesions, decreased serum levels of lactate dehydrogenase, myeloperoxidase, and reduced tissue content of malondialdehyde. Moreover, monophosphoryl lipid A markedly increased plasma concentrations of calcitonin gene-related peptide. Pretreatment with capsaicin, which specifically depletes the neurotransmitter content of sensory nerves or calcitonin gene-related peptide-(8-37), a selective calcitonin gene-related peptide receptor antagonist, inhibited the increased calcitonin gene-related peptide release and subsequently abrogated the protection by monophosphoryl lipid A.. In conclusion, monophosphoryl lipid A pharmacologically mimics delayed preconditioning and the protective effects are related to the stimulation of calcitonin gene-related peptide release in rat small intestine.

Topics: Animals; Calcitonin Gene-Related Peptide; Capsaicin; Gene Expression Regulation; Intestine, Small; Ischemic Preconditioning; L-Lactate Dehydrogenase; Lipid A; Male; Malondialdehyde; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Diabetes is an important risk factor for ischemic acute kidney injury, whose pharmacological treatment remains an unmet medical need. The peroxisome proliferator-activated receptor (PPAR) β/δ is highly expressed in the kidney, although its role has not yet been elucidated. Here, we used an in vivo model of renal ischemia/reperfusion (I/R) in streptozotocin-induced diabetic rats (i) to evaluate whether diabetes increases kidney susceptibility to I/R injury and (ii) to investigate the effects of PPARβ/δ activation. The degree of renal injury (1h ischemia/6h reperfusion) was significantly increased in diabetic rats compared with nondiabetic littermates. PPARβ/δ expression was increased after I/R, with the highest levels in diabetic rats. Administration of the selective PPARβ/δ agonist GW0742 attenuated the renal dysfunction, leukocyte infiltration, and formation of interleukin-6 and tumor necrosis factor-α. These effects were accompanied by an increased expression of the suppressor of cytokine signaling (SOCS)-3, which plays a critical role in the cytokine-activated signaling pathway. The beneficial effects of GW0742 were attenuated by the selective PPARβ/δ antagonist GSK0660. Thus, we report herein that PPARβ/δ activation protects the diabetic kidney against I/R injury by a mechanism that may involve changes in renal expression of SOCS-3 resulting in a reduced local inflammatory response.

Topics: Animals; Blotting, Western; Cells, Cultured; Diabetes Mellitus, Experimental; Kidney; Male; Peroxidase; PPAR delta; PPAR-beta; Rats; Rats, Wistar; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Thiazoles

The aim of this study is to evaluate the role of Rho-kinase in the pathogenesis of lung injury induced by intestinal ischemia/reperfusion (I/R) and the preconditioning effects of fasudil hydrochloride. The novel therapeutic approach of using Rho-kinase inhibitors in the treatment of intestinal I/R is introduced.. Sprague-Dawley (SD) rats were divided into 4 groups: intestinal I/R group, two fasudil pretreatment groups (7.5 mg/kg and 15 mg/kg), and controls. Intestinal and lung histopathology was evaluated; myeloperoxidase (MPO) and superoxide dismutase (SOD) levels in lung parenchyma were determined. Serum tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were measured. eNOS and P-ERM expression were measured by Western Blot.. Lung and intestinal injury were induced by intestinal I/R, characterized by histological damage and a significant increase in BALF protein. Compared to controls, serum TNF-α, IL-6, and lung MPO activity increased significantly in the I/R group, while SOD activity decreased. A strongly positive P-ERM expression was observed, while eNOS expression was weak. After fasudil administration, injury was ameliorated. Serum TNF-α, IL-6, lung MPO and P-ERM expression decreased significantly as compared to the I/R group, while SOD activity and eNOS expression increased significantly.. Rho-kinase plays a key role in the pathogenesis of lung injury induced by intestinal I/R. The inhibition of the Rho-kinase pathway by fasudil hydrochloride may prevent lung injury.

Topics: 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; Acute Lung Injury; Animals; Interleukin-6; Intestines; Ischemia; Lung; Male; Nitric Oxide Synthase Type III; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; rho-Associated Kinases; Superoxide Dismutase; Tumor Necrosis Factor-alpha

Topics: Animals; Apoptosis; Caspase 3; Interleukin-1beta; Kidney; Kidney Transplantation; Leukocyte Reduction Procedures; Leukocytes; Models, Animal; Organ Preservation; Peroxidase; Reperfusion Injury; Swine

Gut injury and loss of normal intestinal barrier function are key elements in the paradigm of gut-origin systemic inflammatory response syndrome, acute lung injury, and multiple organ dysfunction syndrome (MODS). As hypoxia-inducible factor (HIF-1) is a critical determinant of the physiological and pathophysiological response to hypoxia and ischemia, we asked whether HIF-1 plays a proximal role in the induction of gut injury and subsequent lung injury. Using partially HIF-1α-deficient mice in an isolated superior mesenteric artery occlusion (SMAO) intestinal ischemia reperfusion (I/R) injury model (45 min SMAO followed by 3 h of reperfusion), we showed a direct relationship between HIF-1 activation and intestinal I/R injury. Specifically, partial HIF-1α deficiency attenuated SMAO-induced increases in intestinal permeability, lipid peroxidation, mucosal caspase-3 activity, and IL-1β mRNA levels. Furthermore, partial HIF-1α deficiency prevented the induction of ileal mucosal inducible nitric oxide synthase (iNOS) protein levels after SMAO and iNOS deficiency ameliorated SMAO-induced villus injury. Resistance to SMAO-induced gut injury was also associated with resistance to lung injury, as reflected by decreased levels of myeloperoxidase, IL-6 and IL-10 in the lungs of HIF-1α(+/-) mice. In contrast, a short duration of SMAO (15 min) followed by 3 h of reperfusion neither induced mucosal HIF-1α protein levels nor caused significant gut and lung injury in wild-type or HIF-1α(+/-) mice. This study indicates that intestinal HIF-1 activation is a proximal regulator of I/R-induced gut mucosal injury and gut-induced lung injury. However, the duration and severity of the gut I/R insult dictate whether HIF-1 plays a gut-protective or deleterious role.

Topics: Acute Lung Injury; Animals; Blotting, Western; Caspase 3; Enzyme-Linked Immunosorbent Assay; Genotype; Hypoxia-Inducible Factor 1; Intestinal Diseases; Intestinal Mucosa; Intestines; Malondialdehyde; Mice; Mice, Inbred C57BL; Mice, Knockout; Nitric Oxide Synthase Type II; Permeability; Peroxidase; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction

Experiments were designed to investigate the effects of ethyl pyruvate (EP) in a murine model of hind-limb ischemia-reperfusion (IR) injury.. C57BL6 mice underwent 90 minutes of unilateral ischemia followed by 24 hours of reperfusion using two treatment protocols. For the preischemic treatment (pre-I) protocol, mice (n=6) were given 300 mg/kg EP before ischemia, followed by 150 mg/kg of EP just before reperfusion and at 6 hours and 12 hours after reperfusion. In a postischemic treatment (post-I) protocol, mice (n=7) were treated with 300 mg/kg EP at the end of the ischemic period, then 15 minutes later, and 2 hours after reperfusion and 150 mg/kg of EP at 4 hours, 6 hours, 10 hours, 16 hours, and 22 hours after reperfusion. Controls mice for both protocols were treated with lactated Ringers alone at time intervals identical to EP. Skeletal muscle levels of adenosine triphosphate (ATP), interleukin-1β, keratinocyte chemoattractant protein, and thrombin antithrombin-3 complex were measured. Skeletal muscle architectural integrity was assessed microscopically.. ATP levels were higher in mice treated with EP compared with controls under the both treatment protocols (p=0.02). Interleukin-1β, keratinocyte chemoattractant protein, thrombin antithrombin-3 complex (p<0.05), and the percentage of injured fibers (p<0.0001) were significantly decreased in treated versus control mice under the both protocols.. Muscle fiber injury and markers of tissue thrombosis and inflammation were reduced, and ATP was preserved with EP in pre-I and post-I protocols. Further investigation of the efficacy of EP to modulate IR injury in a larger animal model of IR injury is warranted.

Topics: Adenosine Triphosphate; Animals; Antithrombin III; Disease Models, Animal; Inflammation; Interleukin-1; Lactates; Mice; Mice, Inbred C57BL; Muscle, Skeletal; Peptide Hydrolases; Peroxidase; Pyruvates; Reperfusion Injury; Thrombosis

Systemic inflammatory response following ischemia-reperfusion injury (IRI) to a specific organ may cause injuries in multiple remote organs. The emergence of ischemic postconditioning (IPO) provides a potential method for experimentally and clinically attenuating various types of organ postischemic injuries. We have shown that IPO can attenuate lung IRI by up-regulating the protein expression of heme oxygenase-1(HO-1). This study tested the hypothesis that IPO attenuates systemic inflammatory responses following lung IRI by activating HO-1.. Anaesthetized and mechanically ventilated adult Sprague-Dawley rats were randomly assigned to one of the following groups (n = 8 each): the sham-operated control group, the ischemia-reperfusion (IR) group (40 min of left-lung ischemia and 120 min of reperfusion), the IPO group (three successive cycles of 30-s reperfusion per 30-s occlusion before restoring full perfusion), and the zinc protoporphyrin IX (ZnP) plus IPO group (ZnP, an inhibitor of HO-1, was injected intraperitoneally at 20 mg/kg 24 h prior to the experiment, and the rest of the procedures were similar to that of the IPO group). Lung injury was assessed by arterial blood gas analysis, wet-to-dry lung weight ratio and tissue histologic and biochemical changes. The lung tissue and plasma levels of lipid peroxidation were determined by measuring the contents of malondialdehyde (MDA) production. Protein expression of HO-1 was determined by Western blotting. Pulmonary neutrophil was counted. Lung tissue myeloperoxidase (MPO) activity as well as plasma levels of proinflammatory cytokines tumor necrosis factor-α (TNF-α), interleukines 6 and 8 (IL-6, IL-8) were determined by spectrophotography.. Lung ischemia-reperfusion led to severe lung pathologic morphologic changes and increased pulmonary MDA production, neutrophil count, and MPO activity and reduced arterial oxygen partial pressure (all P < 0.05 IR versus sham), accompanied with a compensatory increase in HO-1 protein and activity. Plasma levels of TNF-α, IL-6, and IL-8 were increased in the IR group (all P < 0.05 versus sham). IPO attenuated or prevented all the above changes, except that it further increased lung HO-1 activity. Treatment with ZnP abolished all the protective effects of postconditioning.. Postconditioning attenuated pulmonary neutrophil accumulation and activation and lung IRI and reduced systemic inflammatory responses by activating HO-1.

Topics: Animals; Blood Gas Analysis; Cytokines; Female; Heme Oxygenase (Decyclizing); Interleukin-6; Interleukin-8; Ischemic Preconditioning; Lung; Male; Neutrophils; Organ Size; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

Hepatic I/R injury is unavoidable in liver transplantation and surgery. This remains a significant problem in surgical procedures. The purpose of this study was to investigate the effects of triptolide on liver ischemia/reperfusion (I/R) injury and related mechanisms in mice.. Male C57BL/6 mice were randomized into four groups: (1) sham group; (2) sham-triptolide group; (3) I/R group; and (4) I-R/triptolide group. Ninety minutes of warm ischemia was induced and flow by 24 h reperfusion. Serum alanine aminotransferase and aspartate aminotransferase were assayed, pathologic alterations and (NF)-κB p65 immunohistochemistry were observed. Liver malondialdehyde (MDA) level, activity of endogenous antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities, and activity of neutrophil accumulation marker myeloperoxidase (MPO) were measured. TNF-α, IL-6, and IL-1β mRNA were detected by RT-PCR, whereas nuclear factor (NF)-κB p65 and IκBα were assessed with Western blotting.. Plasma aminotransferase activity was higher in the I/R group than in the I/R-triptolide group. MDA level and neutrophil infiltration were also markedly reduced, while SOD, CAT, and GSH-Px levels increased in I/R-triptolide group compared with I/R group. In group 4, histopathologic changes were significantly attenuated in triptolide-treated livers. In comparison with group 3, triptolide reduced NF-κB p65 nuclear and IκBα expression, and effectively suppressed pro-inflammatory cytokine level during the I/R.. These results suggest that triptolide has protective effects against hepatic I/R injury. Its mechanisms might be related to reduction of oxidative stress and neutrophil infiltration and inhibition NF-κB p65 activity.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Diterpenes; Epoxy Compounds; I-kappa B Proteins; Immunosuppressive Agents; Interleukin-1beta; Interleukin-6; Liver Diseases; Male; Malondialdehyde; Mice; Mice, Inbred C57BL; Neutrophils; NF-kappa B; NF-KappaB Inhibitor alpha; Oxidative Stress; Peroxidase; Phenanthrenes; Reperfusion Injury; RNA, Messenger; Tumor Necrosis Factor-alpha

Ischemia-reperfusion (I/R) injury is a major factor leading to intestinal dysfunction or graft loss after intestinal surgery or transplantation. This study investigated the cytoprotective effects and putative mechanisms of interleukin (IL)-13 after intestinal I/R injury in the mouse.. Mouse warm intestinal I/R injury induced by clamping the superior mesenteric artery for 100 min with tissue analysis at 4 and 24 hr after reperfusion. Treated animals received intravenous recombinant murine IL-13 (rIL-13) and anti-IL-13 antibody, whereas controls received saline.. rIL-13 administration markedly prolonged animal survival (100% vs. 50% in saline controls) and resulted in near normal histopathological architecture. rIL-13 treatment also significantly decreased myeloperoxidase activity. Mice conditioned with rIL-13 had a markedly depressed Toll-like receptor-4 expression and increased the expression of Stat6, antioxidant hemeoxygenase-1, and antiapoptotic A20, Bcl-2/Bcl-xl, compared with that of controls. Unlike in controls, the expression of mRNA coding for IL-2/interferon-γ, and interferon-γ-inducible protein (IP)-10/monocyte chemotactic protein-1 remained depressed, whereas that of IL-13/IL-4 reciprocally increased in the mice treated with rIL-13. Administration of anti-IL13 antibody alone or in combination with rIL-13 resulted in outcomes similar to that seen in controls.. This study demonstrates for the first time that IL-13 plays a protective role in intestinal warm I/R injury and a critical role in the regulation of Stat6 and Toll-like receptor-4 signaling. The administration of IL-13 exerts cytoprotective effects in this model by regulating innate and adaptive immunity while the removal of IL-13 using antibody therapy abrogates this effect.

Topics: Adaptive Immunity; Animals; Cytoprotection; Immunity, Innate; Interleukin-13; Intestines; Male; Mice; Mice, Inbred C57BL; Peroxidase; Recombinant Proteins; Reperfusion Injury; STAT6 Transcription Factor; Toll-Like Receptor 4

Ischemia-reperfusion is a major event for induction of cellular apoptosis. Apoptosis is due to the activation of death receptor and/or mitochondrial pathways. Mitochondrial permeability transition pore opening is the cause of apoptosis. In our present study, we tried to evaluate the role of flunarizine in ischemia and reperfusion of celiac artery-induced gastric lesion in the rat.. The therapeutic potential of flunarizine was assessed by measuring the changes in gastric lesion index, biomarker (i.e., thiobarbituric acid reactive substance, reduced glutathione, superoxide dismutase, myeloperoxidase, and total calcium and protein content), and mitochondrial damage (i.e., adenosine triphosphate and deoxyribonucleic acid fragmentation content) in ischemia and reperfusion-induced gastric lesion model.. Medium and higher doses of flunarizine produced a significant (P<0.05) ameliorative effect which was observed from the assessment of all the above-mentioned parameters (i.e., increase in reduced glutathione, superoxide dismutase and decrease in thiobarbituric acid reactive substance, myeloperoxidase, and total calcium content). Similar results were also obtained from omeprazole and cyclosporine. In the pre-treated group, deoxyribonucleic acid fragmentation pattern has also indicated that a mitochondria-associated anti-apoptotic effect of flunarizine was responsible to prevent the ischemia and reperfusion of celiac artery-induced gastric lesion.. The gastroprotective effect of flunarizine may be produced due to its inactivation potential of mitochondrial permeability transition pore opening associated with anti-oxidative, calcium regulation along with its anti-apoptotic effect.

Topics: Animals; Anti-Ulcer Agents; Apoptosis; Calcium; Celiac Artery; Cyclosporine; Flunarizine; Glutathione; Immunosuppressive Agents; Male; Mitochondria; Omeprazole; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Stomach; Superoxide Dismutase; Thiobarbituric Acid Reactive Substances; Vasodilator Agents

The effects of hydroxyethyl starch 130/0.4 (HES130/0.4) on myocardial ischemia/reperfusion (I/R) injury and its mechanism are uncertain. The aim of this study was to investigate the protective effects of HES 130/0.4 on myocardial I/R injury.. Forty-eight Sprague-Dawley rats were assigned to sham-operation group (S group), ischemia-reperfusion group (I/R group), albumin-I/R group (A-I/R group) and HES130/0.4-I/R group (H-I/R group). The fluids were administered at 25 minutes after ischemia. H-I/R group was given 7.5 ml/kg of HES 130/0.4; I/R group and A-I/R group received the same volume of normal saline and 5% albumin, respectively. The rats in S group were sham operated and received the same fluid as I/R group. After 30 minutes of ischemia and 3 hours of reperfusion, blood samples were taken for cytokines assay, myocardium was excised for detection of NF-κB activity and myocardial infarction areas were taken for immunohistochemical analysis.. Hemodynamic parameters of H-I/R group were better than I/R and A-I/R groups at all designated time points. The results of 2,3,5-triphenyl-tetrazolium (TTC) and HE staining were better in the H-I/R group. Myeloperoxidase (MPO), NF-κB activity and concentrations of TNF-α, IL-1β were elevated markedly in I/R groups. HES130/0.4 lessened the release of TNF-α and IL-1β consistent with the reduction of MPO activity, and HES 130/0.4 inhibited the activity of NF-κB in H-I/R group. The number of apoptotic cells in the H-I/R group was also significantly reduced compared with I/R and A-I/R group. HES130/0.4 has a protective effect on I/R injured myocardium, probably by inhibiting NF-κB activity, reducing the release of pro-inflammatory cytokines and interfering with the apoptosis of cardiomyocytes.

Topics: Animals; Hemodynamics; Hydroxyethyl Starch Derivatives; Interleukin-1beta; Male; NF-kappa B; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

The present study investigated the actions of des-aspartate-angiotensin I (DAA-I) on infarct size and three early inflammatory events in acute myocardial ischemia-reperfusion injury in rats. The rationale was based on earlier findings showing that chronic daily administration of DAA-I attenuated infarct size of ischemic-reperfused rat heart, and cardiac hypertrophy in pressure overload rats. Anesthetized rats were subjected to 45 min of ischemia and 5h of reperfusion. Infarcted area, serum creatine kinase, and tissue myeloperoxidase activity were determined. The expression of intercellular adhesion molecule-1 (ICAM-1) was also investigated by immunohistochemistry and Western blotting. Intravenous administration of DAA-I at 5 min post reperfusion reduced myocardial infarct size by 45.5%, lowered serum creatine kinase activity, decreased myeloperoxidase activity in cardiac tissue, and inhibited the expression of ICAM-1 in cardiac capillary endothelium. The maximum effective dose was 1013 pmol/kg, and the cardioprotective actions of DAA-I were blocked by indomethacin. The data showed that the cardioprotection accorded by DAA-I was the result of its anti-inflammatory actions on early inflammatory processes in myocardial ischemia-reperfusion injury. The anti-inflammatory processes were indomethacin sensitive and probably mediated by prostaglandins.

Topics: Angiotensin I; Animals; Creatine Kinase; Gene Expression Regulation; Intercellular Adhesion Molecule-1; Male; Myocardial Infarction; Myocardial Ischemia; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

The neuronal damage following cerebral ischemia is a serious risk to stroke patients. The aim of this study was to investigate the neuroprotective effects of alkaloid extract from Leonurus heterophyllus (LHAE) on cerebral ischemic injury. After 24 h of reperfusion following ischemia for 2 h induced by middle cerebral artery occlusion (MCAO), some rats were intraperitoneally administered different doses of LHAE (3.6, 7.2, 14.4 mg/kg, respectively). Neurological examination was measured in all animals. Infarct volume, myeloperoxidase (MPO) activity, levels of nitrate/nitrite metabolite (NO) and apoptosis ratio of nerve fiber in brain were determined. The results showed that LHAE at 7.2 mg/kg or 14.4 mg/kg exerted significantly decreasing neurological deficit scores and reducing the infarct volume on rats with focal cerebral ischemic injury (p<0.05). At those dose, the MPO content were significantly decreased in ischemic brain as compared with model group (p<0.05). LHAE at 14.4 mg/kg significantly decreased the NO level compared with the model group (p<0.05). In addition, LHAE significantly decreased the apoptosis ratio of nerve fiber compared with the model group (p<0.05). This study suggests that LHAE may be used for treatment of ischemic stroke as a neuroprotective agent. Further studies are warranted to assess the efficacy and safety of LHAE in patients.

Topics: Alkaloids; Animals; Apoptosis; Brain Ischemia; Infarction, Middle Cerebral Artery; Leonurus; Male; Models, Neurological; Nerve Fibers; Neuroprotective Agents; Nitrates; Nitrites; Peroxidase; Phytotherapy; Plant Extracts; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Ischemia-reperfusion (IR) injury following lung transplantation remains a major source of early morbidity and mortality. Histologically, this inflammatory process is characterized by neutrophil infiltration and activation. We previously reported that lung IR injury was significantly attenuated in plasminogen activator inhibitor-1-deficient mice. In this study, we explored the potential role of tissue plasminogen activator (tPA) in a mouse lung IR injury model. As a result, tPA knockout (KO) mice were significantly protected from lung IR injury through several mechanisms. At the cellular level, tPA KO specifically blocked neutrophil extravasation into the interstitium, and abundant homotypic neutrophil aggregation (HNA) was detected in the lung microvasculature of tPA KO mice after IR. At the molecular level, inhibition of neutrophil extravasation was associated with reduced expression of platelet endothelial cell adhesion molecule-1 mediated through the tPA/ LDL receptor-related protein/NF-κB signaling pathway, whereas increased P-selectin triggered HNA. At the functional level, tPA KO mice incurred significantly decreased vascular permeability and improved lung function following IR. Protection from lung IR injury in tPA KO mice occurs through a fibrinolysis-independent mechanism. These results suggest that tPA could serve as an important therapeutic target for the prevention and treatment of acute IR injury after lung transplantation.

Topics: Airway Resistance; Animals; Blood Pressure; Capillary Permeability; Lung Compliance; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophil Infiltration; P-Selectin; Peroxidase; Platelet Endothelial Cell Adhesion Molecule-1; Reperfusion Injury; Tissue Plasminogen Activator

Inflammation contributes to the pathogenesis of ischemic acute kidney injury (AKI), and T cells mediate the early phase of ischemia-reperfusion injury (IRI). The Fas/Fas ligand (FasL) pathway modulates the balance of T cell subsets in the peripheral circulation as well as multiple inflammatory responses, suggesting that FasL may mediate ischemic AKI. Here, we induced bilateral renal IRI in mice bearing a loss-of-function mutation of FasL (the gld mutation) and in wild-type mice. Compared with wild-type mice, serum creatinine was lower in gld mice (1.4 ± 0.9 mg/dl versus 2.6 ± 0.4) at 24 hours after IRI (P<0.05). In addition, gld mice had fewer TNF-α-producing T lymphocytes in the kidneys and renal lymph nodes. Furthermore, pharmacologic blockade of FasL protected the kidneys of wild-type mice from IRI. Analysis of bone marrow chimeric mice suggested that the pathogenic effect of FasL involves leukocytes; reconstitution of wild-type mice with gld splenocytes attenuated IRI. In contrast, reconstitution of gld mice with wild-type splenocytes enhanced IRI. These data demonstrate that FasL, particularly on leukocytes, mediates ischemic AKI.

Topics: Acute Kidney Injury; Animals; Caspase 3; Fas Ligand Protein; Leukocytes; Lymph Nodes; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Models, Animal; Peroxidase; Reperfusion Injury; Spleen; T-Lymphocytes; Tumor Necrosis Factor-alpha

To evaluate the effects of growth hormone (GH) as an antioxidant and tissue-protective agent and analyse the biochemical and histopathological changes in rat ovaries due to experimental ischemia and ischemia/reperfusion injury.. Forty-eight adult female rats were randomly divided into eight groups. In Group 1, a period of bilateral ovarian ischemia was applied. In Groups 2 and 3, 1 and 2 mg/kg of GH was administered, and 30 min later, bilateral ovarian ischemia was applied (after a 3-h period of ischemia, both ovaries were surgically removed). Group 4 received a 3-h period of ischemia followed by 3h of reperfusion. Groups 5 and 6 received 1 and 2 mg/kg of GH, respectively, 2.5 h after the induction of ischemia. At the end of a 3-h period of ischemia, bilateral vascular clips were removed, and 3h of reperfusion continued. Group 7 received a sham operation plus 2mg/kg of GH. Group 8 received a sham operation only. After the experiments, superoxide dismutase and myeloperoxidase activity and levels of glutathione and lipid peroxidation were determined, and histopathological changes were examined in all rat ovarian tissue.. Ischemia and ischemia/reperfusion decreased superoxide dismutase activity and glutathione levels in ovarian tissue, but increased lipid peroxidation levels and myeloperoxidase activity significantly in comparison to the sham group. The 1 and 2 mg/kg doses of GH before ischemia and ischemia/reperfusion decreased lipid peroxidation levels and myeloperoxidase activity in the experimental groups. The administration of GH before ischemia and ischemia/reperfusion treatments also increased superoxide dismutase and glutathione levels. The histopathological findings also suggested a protective role of GH in ischemia/reperfusion injury. That is, ovarian tissues in the ischemia groups showed histopathological changes, such as haemorrhage, cell degeneration, and necrotic and apoptotic cells, but these changes in the GH groups were lesser. Moreover, in the ischemia/reperfusion groups, acute inflammatory processes--such as neutrophil adhesion and migration, apoptotic and degenerative cells, stromal oedema and haemorrhage--were present. However, the ovarian tissues of the IR+GH (1 mg) group had minimal apoptotic cells, and the IR+GH (2 mg) group had no apoptotic cells. In addition, the general ovarian histological structures of these groups were similar to those of the healthy control group.. The administration of GH is protective against ischemia and/or ischemia/reperfusion-induced ovarian damage. This protective effect can be attributed to the antioxidant properties of GH.

Topics: Animals; Antioxidants; Apoptosis; Dose-Response Relationship, Drug; Edema; Female; Glutathione; Hemorrhage; Human Growth Hormone; Ischemia; Lipid Peroxidation; Neutrophil Activation; Ovary; Oxidative Stress; Peroxidase; Random Allocation; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase; Torsion, Mechanical

Inflammation, which is known to be detrimental to the neurologic outcome during the acute phase after an ischemic stroke, provides a potential target for preventive or therapeutic approach for spinal cord ischemia-reperfusion injury. Tetramethylpyrazine (TMP), a pure compound derived from Ligusticum chuanxiong, is widely used in the treatment of ischemic stroke. The present study aimed to gain a deeper insight into the mechanism underlying the anti-inflammatory effects of TMP on spinal cord ischemia-reperfusion injury.. Spinal cord ischemia was induced in male Sprague-Dawley rats by balloon occlusion of the thoracic aorta. The experimental groups (n = 30 per group) included sham operation, control (receiving only normal saline), and TMP (30 mg/kg, 30 minutes before occlusion). Neurologic function was assessed by the Basso, Beattie, and Bresnahan (BBB) score at 1, 6, 12, 24, and 48 hours after reperfusion. Histologic changes were studied using Nissl staining. Infarct volume was analyzed using 2,3,5-triphenyltetrazolium chloride staining. Myeloperoxidase (MPO) activity was determined by using a rat MPO assay kit. Interleukin (IL)-1β, tumor necrosis factor (TNF)-α, IL-10 and nuclear factor (NF)-κB were examined with immunohistochemistry, enzyme-linked immunosorbent assay (ELISA) and Western blotting.. Compared with the control group, the TMP group showed significantly improved neurologic outcome (P < .05), decreased infarct volume (42.3% vs 17.4%), and alleviated neutrophil infiltration (0.35 vs 0.18 U/g). TMP treatment reduced the expressions of proinflammatory cytokines TNF-α (28.62 vs 15.23 pg/mg protein) and IL-1β (13.62 vs 8.24 pg/mg protein), upregulated the expression of anti-inflammatory cytokine IL-10 (18.35 vs 31.26 pg/mg protein), and inhibited the activation of NF-κB (2.78 vs 1.22) in ischemic spinal cord.. Treatment with TMP exerted a neuroprotective effect against spinal cord ischemia-reperfusion injury. The anti-inflammatory effect was believed to be one of the contributing mechanisms.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Blotting, Western; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Immunohistochemistry; Inflammation Mediators; Interleukin-10; Interleukin-1beta; Male; Neurologic Examination; Neuroprotective Agents; Neutrophil Infiltration; NF-kappa B; Peroxidase; Pyrazines; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Spinal Cord; Spinal Cord Ischemia; Time Factors; Tumor Necrosis Factor-alpha

Nonalcoholic fatty liver disease (NAFLD) refers to an increasingly diagnosed condition involving triglyceride accumulation into hepatocytes resulting in a broad spectrum of liver injury. The progression of NAFLD, a relatively benign condition, to nonalcoholic steatohepatitis (NASH) involves the hepatic infiltration of inflammatory cells and subsequent hepatocellular injury. Ischemia/reperfusion (I/R) injury of the liver is a major complication of liver resection, hepatic trauma, and liver transplantation. To date, there have been no studies that have evaluated the effects of hepatic I/R on models of NASH.. Evaluate the effects of hepatic I/R on a mouse model of NASH.. A mouse model of progressive NASH was developed and evaluated using C57BL/6 mice fed a methionine choline deficient diet for 3, 6, 9, and 12 wk. Mice subsequently underwent 90 min of partial hepatic ischemia with reperfusion of 1, 4, and 8 h. Mice were sacrificed after the indicated periods, and blood and liver samples were taken for analysis.. Mice fed the MCD diet showed a rapid induction of hepatic steatosis, inflammation, and fibrosis by 3 wk that persisted over the 12-wk period of diet, as demonstrated by histologic examination, alanine aminotransferase (ALT), and liver content of myeloperoxidase (MPO). The response to I/R in livers with progressive NASH fed MCD diet for 3, 6, 9, and 12 wk showed marked neutrophil recruitment and hepatocyte necrosis.. These data suggest the inflammatory response from I/R is augmented in livers with NASH histopathology compared with normal liver.

Topics: Alanine Transaminase; Animals; Diet; Disease Models, Animal; Disease Progression; Fatty Liver; Ischemia; Liver; Male; Methionine; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Peroxidase; Reperfusion Injury

Lower limb ischemia-reperfusion (I/R) elicits oxidative stress and causes inflammation in lung tissues that may lead to lung injury. Magnesium sulfate (MgSO(4)) possesses potent anti-oxidation and anti-inflammation capacity. We sought to elucidate whether MgSO(4) could mitigate I/R-induced lung injury. As MgSO(4) is an L-type calcium channel inhibitor, the role of the L-type calcium channels was elucidated.. Adult male rats were allocated to receive I/R, I/R plus MgSO(4) (10, 50, or 100 mg/kg), or I/R plus MgSO(4) (100 mg/kg) plus the L-type calcium channels activator BAY-K8644 (20 μg/kg) (n = 12 in each group). Control groups were run simultaneously. I/R was induced by applying rubber band tourniquets high around each thigh for 3 h followed by reperfusion for 3 h. After euthanization, degrees of lung injury, oxidative stress, and inflammation were determined.. Arterial blood gas and histologic assays, including histopathology, leukocyte infiltration (polymorphonuclear leukocytes/alveoli ratio and myeloperoxidase activity), and lung water content, confirmed that I/R caused significant lung injury. Significant increases in inflammatory molecules (chemokine, cytokine, and prostaglandin E(2) concentrations) and lipid peroxidation (malondialdehyde concentration) confirmed that I/R caused significant inflammation and oxidative stress in rat lungs. MgSO(4), at the dosages of 50 and 100 mg/kg but not 10 mg/kg, attenuated the oxidative stress, inflammation, and lung injury induced by I/R. Moreover, BAY-K8644 reversed the protective effects of MgSO(4).. MgSO(4) mitigates lung injury induced by bilateral lower limb I/R in rats. The mechanisms may involve inhibiting the L-type calcium channels.

Topics: Acute Lung Injury; Animals; Blood Gas Analysis; Blood Pressure; Calcium Channel Blockers; Calcium Channels, L-Type; Cyclooxygenase 2; Dinoprostone; Extravascular Lung Water; Heart Rate; Hindlimb; Magnesium Sulfate; Male; Neutrophils; Nitric Oxide; Oxidative Stress; Peroxidase; Pneumonia; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Intestinal ischemia/reperfusion (I/R) injury is implicated in many clinical conditions, and it performs a fundamental role in their pathophysiologies. Oral administration of antioxidants and nitric oxide (NO) donors ameliorate intestinal injury. Here, the effects of l-arginine, allopurinol and N(G)-nitro-l-arginine methyl ester (l-NAME) were investigated.. One hundred twenty-eight male Wistar rats were separated into 4 groups and subjected to occlusion of the superior mesenteric artery for 60 min. The Control group did not receive any substance before the surgical operation. However, the 3 other groups received the following: l-arginine (800 mg/kg body weight; l-Arg group), l-NAME (50mg/kg; l-NAME group) or allopurinol (100mg/kg; Allo group). Each substance was given by mouth in 3 equal doses 24, 12 and 1h before the surgical operation. Each group was then divided into 4 subgroups, which underwent different durations of reperfusion (0, 1, 8 or 24h). At the end of each time point, blood and tissue samples were collected, and histological examinations were performed. Serum nitrite and catalase, intestinal tissue myeloperoxidase (MPO), inducible nitric oxide synthase (iNOS) and nitrotyrosine (NT) levels were determined.. At each reperfusion time point, the Allo group exhibited the mildest histological lesions in contrast to the l-NAME group, which showed the most severe lesions. MPO was decreased significantly in the Allo and l-Arg groups during reperfusion, and allopurinol administration caused earlier and stronger effect. iNOS and NT levels were higher in the l-Arg group and lower in the Allo group. Serum nitrite and catalase were increased in the l-NAME group after 24h.. Oral administration of allopurinol exerted a strong and protective effect on the intestinal tissue that was subjected to I/R earlier than l-arginine. This finding was also supported with the MPO, iNOS and NT data.

Topics: Administration, Oral; Allopurinol; Animals; Arginine; Catalase; Intestines; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide Synthase Type II; Nitrites; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Time Factors; Tyrosine

The present study investigated the protective effect of L-citrulline on gastric mucosal injury induced by ischemia-reperfusion (IR) in rats. Under anesthesia, the celiac artery was clamped for 30 min, and then the clamp was removed for 60 min reperfusion. Sixty minutes before ischemia, L-citrulline was administered intragastrically at doses of 300, 600, and 900 mg/kg. After the experiment, the stomachs were removed for biochemical and histological examinations. Pretreatment with L-citrulline (300, 600, and 900 mg/kg) significantly ameliorated the gastric damage caused by IR. Moreover, L-citrulline prevented the production of lipid peroxidation and inhibited the increase of myeloperoxidase activity. The elevation in total nitric oxide synthase (NOS) activity, inducible NOS activity, and inducible NOS protein expression as well as the decrease in constitutive NOS activity and gastric mucus level in the gastric mucosa induced by IR were significantly prevented. However, the protective effect mediated by L-citrulline was significantly antagonized by coadministration of L-nitroarginine methyl ester (10 mg/kg, s.c.). These results suggest that part of the mechanism of gastric protection by L-citrulline might be through inhibiting neutrophil infiltration and preserving gastric mucus synthesis and secretion in rats, functions that are closely related to the maintenance of constitutive NOS activity.

Topics: Amidines; Animals; Arginine; Benzylamines; Celiac Artery; Citrulline; Enzyme Inhibitors; Gastric Mucosa; Hexosamines; Ligation; Male; Malondialdehyde; Mucus; NG-Nitroarginine Methyl Ester; Nitric Oxide Synthase; Nitric Oxide Synthase Type I; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Peroxidase; Protective Agents; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Stomach

Renal ischemia-reperfusion injury causes acute renal failure, and the hallmarks of renal ischemia-reperfusion injury are inflammation, apoptosis, necrosis, and capillary dysfunction. Milk fat globule-epidermal growth factor-factor VIII (MFG-E8), a membrane-associated secretory glycoprotein, is produced by immune cells and reported to participate in multiple physiologic processes associated with tissue remodeling. We have recently shown that MFG-E8 treatment attenuates organ injury, inflammatory responses, and survival after sepsis through the enhancement of phagocytosis of apoptotic cells. The purpose of this study was to determine whether administration of MFG-E8 attenuates renal ischemia-reperfusion injury.. Prospective, controlled, and randomized animal study.. : A research institute laboratory.. Male C57BL/6J mice (20-25 g).. : Renal ischemia-reperfusion injury with bilateral renal pedicle clamping for 45 mins, followed by reperfusion. A recombinant murine MFG-E8 (0.4 μg/20 g) was given intraperitoneally at the beginning of reperfusion.. MFG-E8 levels, organ injury variables, inflammatory responses, histology, apoptosis, and capillary functions were assessed at 1.5 and 20 hrs after reperfusion. A 60-hr survival study was conducted in MFG-E8 and recombinant murine MFG-E8-treated wild-type mice. After renal ischemia-reperfusion injury, MFG-E8 mRNA and protein expressions were significantly decreased in the kidneys and spleen. Treatment with recombinant murine MFG-E8 recovered renal dysfunction, significantly suppressed inflammatory responses, apoptosis, necrosis, and improved capillary functions in the kidneys. In the survival study, MFG-E8 mice showed a significant deterioration and, in contrast, recombinant murine MFG-E8-treated wild-type mice showed a significant improvement of survival compared with vehicle-treated wild-type mice.. MFG-E8 can be developed as novel treatment for renal ischemia-reperfusion injury. This protective effect appears to be mediated through the enhancement of apoptotic cell clearance and improvement of capillary functions in the kidneys.

Topics: Animals; Antigens, Surface; Apoptosis; Blotting, Western; Disease Models, Animal; In Situ Nick-End Labeling; Inflammation; Ischemia; Kidney; Liver; Male; Mice; Mice, Inbred C57BL; Milk Proteins; Peroxidase; Recombinant Proteins; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; Spleen

Patients with acute kidney injury (AKI) have increased serum proinflammatory cytokines and an increased occurrence of respiratory complications. The aim of the present study was to examine the effect of renal and extrarenal cytokine production on AKI-mediated lung injury in mice. C57Bl/6 mice underwent sham surgery, splenectomy, ischemic AKI, or ischemic AKI with splenectomy and kidney, spleen, and liver cytokine mRNA, serum cytokines, and lung injury were examined. The proinflammatory cytokines IL-6, CXCL1, IL-1β, and TNF-α were increased in the kidney, spleen, and liver within 6 h of ischemic AKI. Since splenic proinflammatory cytokines were increased, we hypothesized that splenectomy would protect against AKI-mediated lung injury. On the contrary, splenectomy with AKI resulted in increased serum IL-6 and worse lung injury as judged by increased lung capillary leak, higher lung myeloperoxidase activity, and higher lung CXCL1 vs. AKI alone. Splenectomy itself was not associated with increased serum IL-6 or lung injury vs. sham. To investigate the mechanism of the increased proinflammatory response, splenic production of the anti-inflammatory cytokine IL-10 was determined and was markedly upregulated. To confirm that splenic IL-10 downregulates the proinflammatory response of AKI, IL-10 was administered to splenectomized mice with AKI, which reduced serum IL-6 and improved lung injury. Our data demonstrate that AKI in the absence of a counter anti-inflammatory response by splenic IL-10 production results in an exuberant proinflammatory response and lung injury.

Topics: Acute Kidney Injury; Animals; Capillary Leak Syndrome; Chemokine CXCL1; Interleukin-10; Interleukin-1beta; Interleukin-6; Kidney; Liver; Lung Injury; Mice; Mice, Inbred C57BL; Peroxidase; Reperfusion Injury; Severity of Illness Index; Spleen; Splenectomy; Tumor Necrosis Factor-alpha

To investigate whether emulsified isoflurane preconditioning could reduce lung injury induced by hepatic I/R in rats and its mechanism.. 32 pentobarbital-anesthetized Sprague-Dawley rats were equally randomized into four groups: laparotomy group (Sham group), hepatic I/R and normal saline infusion group (I/R+S group), I/R and lipid vehicle infusion (I/R+V group), or I/R and 8% emulsified isoflurane infusion (I/R+E group) at the rate of 8 ml·kg(-1)·h(-1) for 30 min. Blood supply of the hepatic artery and portal vein to the left and the median liver lobes was occluded for 90 min after 30-min washout time. Reperfusion was allowed to proceed for 4 h before sacrifice of the animals. Lung injury was observed histologically. Neutrophil infiltration and TNF-α concentration in serum and lung were measured. Changes of wet-to-dry weight ratios in lung tissue, ICAM-1 expression and NF-κB activity in lung after hepatic I/R were determined.. Compared with I/R+S or I/R+V group, emulsified isoflurane preconditioning reduced hepatic I/R-induced lung histologic injury and inhibited the increase of myeloperoxidase (MPO) activity in the lung tissue markedly (5.5±1.37 and 5.22±1.33 vs 3.81±1.62 U/g, P<0.05). In addition, both serum and lung tissue TNF-α levels were reduced in I/R+E group (104.58±31.40 and 94.60±22.23 vs 72.44±17.28 pg/ml, P<0.05; 393.51±88.22 and 405.46±102.87 vs 292.62±74.56 pg/ml, P<0.01). Emulsified isoflurane preconditioning also inhibited the increase of ICAM-1 expression (0.79±0.17 and 0.84±0.24 vs 0.62±0.21, P<0.05) and NF-κB translocation (4.93±0.48 and 4.76±0.57 vs 4.01±0.86, P<0.05) in the lung tissue markedly.. Emulsified isoflurane preconditioning markedly attenuated hepatic I/R-induced lung injury in rats, which may be hopefully applied to the clinical treatment of organ injury caused by hepatic surgery, transplantation or hemorrhagic shock.

Topics: Acute Lung Injury; Anesthetics, Inhalation; Animals; Blood Gas Analysis; Intercellular Adhesion Molecule-1; Ischemic Preconditioning; Isoflurane; Liver; Lung; Male; NF-kappa B; Peroxidase; Pulmonary Edema; Rats; Rats, Sprague-Dawley; Reperfusion Injury; RNA, Messenger; Tumor Necrosis Factor-alpha

Apocynin suppresses the generation of reactive oxygen species (ROS) that are implicated in ischemia-reperfusion (I/R) lung injury. We thus hypothesized that apocynin attenuates I/R. Furthermore, we explored the mechanisms by which apocynin may attenuate I/R. I/R was induced in an isolated and perfused rat lung model with ischemia for 1 h followed by reperfusion for 1 h. Apocynin was administered in the circulating perfusate at the onset of ischemia. Hemodynamics, lung injury indices, inflammatory responses, and activation of apoptotic pathways were determined. An increase in lung permeability and lung weight gain was noted after I/R. Peak airway pressure was increased, and pH of circulating perfusate was decreased. The adhesion molecule of neutrophil (CD31) in perfusate was upregulated. The levels of albumin, white blood cell count, and inflammatory cytokines including interleukin-1β, tumor necrosis factor-α, and macrophage inflammatory protein-2 increased in lung lavage fluid; the concentrations of carbonyl and thiobarbituric acid reactive substances were greater in the circulating perfusate; and the expression of myeloperoxidase, JNK, P38, and caspase-3 in lung tissue was greater in the control group. Upregulation and activation of nuclear factor-κB (NF-κB) in nuclei were found in I/R. The administration of apocynin attenuated these inflammatory responses and lung permeability associated with decreased activation of NF-κB. We conclude that I/R is associated with inflammatory responses including the generation of ROS, adhesion protein of neutrophil, cytokines, and the activation of mitogen-activated protein kinase and NF-κB cascade. The administration of apocynin attenuates the inflammatory responses and I/R in the isolated, perfused rat lung model.

Topics: Acetophenones; Animals; Anti-Inflammatory Agents, Non-Steroidal; Blotting, Western; Disease Models, Animal; Humans; Immunohistochemistry; Lung; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Mannitol is used as a treatment for ischemia/reperfusion (IR) injury of various organs in humans, despite the fact that its effectiveness in vivo is still disputed. The purpose of this study was to determine the effects of mannitol on acute lung injury (ALI) induced by infrarenal aortic occlusion.. Male Wistar-albino rats were allocated into five groups: (i) sham-operated group, which received a laparotomy without IR injury (n = 12); (ii) IR group, which received 3 h of ischemia followed by 2 h of reperfusion (n = 12); (iii) IR + inferior caval phlebotomy (ICP) group, which was identical to group 2 except for 1 ml of blood aspiration from the inferior caval vein (n = 12); (iv) IR + mannitol-treated group, for which rats were subjected to IR and received a bolus injection of mannitol (n = 12); and (v) IR + ICP + mannitol-treated group, which underwent the same procedures as described for the previous groups. Arterial blood gas parameters were studied and bronchoalveolar lavage (BAL) was performed. Evans blue dye was injected into half of the rats. We biochemically assessed the degree of pulmonary tissue injury by investigating oxidative stress markers and enzymatic and nonenzymatic antioxidant markers, and evaluated ALI by establishing pulmonary leukosequestration and ALI scoring, histopathologically. Pulmonary edema was estimated by using Evans blue dye extravasation and wet/dry weight ratios.. Hypertonic mannitol treatment significantly reduced oxidative stress markers, and significantly increased enzymatic and nonenzymatic antioxidant markers in the lung tissues (P < 0.05). Arterial blood gas parameters were significantly ameliorated (P < 0.05), the BAL cytology was significantly better (P < 0.05), pulmonary leukosequestration and ALI scores were significantly decreased (P < 0.05), and pulmonary edema was significantly alleviated (P < 0.05) by mannitol administration.. This study clearly showed that mannitol treatment significantly attenuated the aortic IR-induced ALI. Further clinical studies are required to clarify whether mannitol has a useful role in ALI during surgeries in which IR-induced organ injury occurs.

Topics: Acute Kidney Injury; Animals; Aorta, Abdominal; Biomarkers; Diuretics, Osmotic; Glutathione; Male; Malondialdehyde; Mannitol; Neutrophils; Oxidative Stress; Peroxidase; Pulmonary Edema; Rats; Rats, Wistar; Reactive Oxygen Species; Renal Artery; Reperfusion Injury; Superoxide Dismutase

Excessive complement activation is an integral part of ischemia and reperfusion (IR) injury (IRI) of organs. In kidney transplantation, the pathologic consequence of IRI and complement activation can lead to delayed graft function, which in turn is associated with acute rejection. Previous strategies to reduce complement-induced IRI required systemic administration of agents, which can lead to increased susceptibility to infections/immune diseases. The objective of this study was to determine whether an increase in complement control defenses of rat kidney endothelium reduces IRI. We hypothesized that increased complement control on the endothelial barrier reduces IR-mediated complement activation and reduces kidney dysfunction.. Fischer 344 rats underwent left kidney ischemia for 45 min and treatment with a novel fusogenic lipid vesicle (FLVs) delivery system to decorate endothelial cells with vaccinia virus complement control protein (VCP), followed by reperfusion for 24 h. Assessment included renal function by serum creatinine and urea, myeloperoxidase assay for neutrophil infiltration, histopathology, and quantification of C3 production in kidneys.. Animals in which the kidney endothelium was bolstered by FLVs+VCP treatment had better renal function with a significant reduction in serum creatinine compared with vehicle controls (P < 0.05). Also, C3 production was significantly reduced (P < 0.05) in treated animals compared with vehicle controls.. Increasing complement control at the endothelial barrier with FLVs+VCP modulates complement activation/production during the first 24 h, reducing renal dysfunction following IRI.

Topics: Animals; Complement Activation; Complement C3; Creatinine; Endothelial Cells; Kidney Diseases; Kidney Function Tests; Liposomes; Male; Neutrophils; Permeability; Peroxidase; Rats; Rats, Inbred F344; Reperfusion Injury; Urea; Viral Proteins

Prolonged compression of limb muscles and subsequent decompression are important in the development of crush syndrome (CS). We applied a simple rubber tourniquet to rat hind limbs to create a CS model.. Anesthetized rats were subjected to bilateral hind limb compression for 5 hours followed by decompression and reperfusion for 0 hour, 1 hour, 3 hours, and 24 hours under monitoring of arterial blood pressure and electrocardiography. Blood and tissue samples were collected for histology, biochemical analysis, and tissue myeloperoxidase activity assessment.. The survival rates of the CS-model groups remained at 100% until 3 hours, however, dropped to 25% at 24 hours after reperfusion mainly because of hyperkalemia and consequent hypotension observed at 1 hour and deteriorated at 3 hours after reperfusion. Rhabdomyolysis evaluated by circulating and histologic markers of injury was found as early as 1 hour and more marked at 3 hours, resulting in impaired renal function 24 hours after reperfusion. Myeloperoxidase activities increased with incremental periods after reperfusion not only in injured limb muscles but also in kidney and lung, suggesting an abnormal interaction between the vascular endothelium and circulating leukocytes after rhabdomyolysis, possibly causing subsequent multiple organ dysfunction frequently encountered in CS.. The findings from this study demonstrate the feasibility of a novel small animal model of extremity crush injury. By using this model, the impact of incremental periods of reperfusion on mortality and remote organ dysfunctions can be characterized. Future studies are necessary to better define a threshold for this injury pattern and the impact of other factors underlying this syndrome.

Topics: Animals; Crush Syndrome; Disease Models, Animal; Electrocardiography; Feasibility Studies; Hindlimb; Kidney Function Tests; Male; Peroxidase; Rats; Rats, Wistar; Reperfusion; Reperfusion Injury; Rhabdomyolysis; Survival Rate; Tourniquets

We conducted this study to evaluate the effects of thoracic epidural anesthesia (TEA) on inflammatory response, lipid peroxidation, and oxidative stress in a rat model of mesenteric ischemia/reperfusion (I/R).. Rats were divided into 4 groups: sham group (n=6; sham laparotomy), control group (n=6; I/R), bupivacaine group (n=6; mesenteric I/R and 20 μL/h 0.5% bupivacaine), and saline group (n=6, mesenteric I/R and 20 μL/h 0.9% saline). I/R injury was established by occluding the superior mesenteric artery for 1 hour followed by 12 hours reperfusion. Blood gas, tumor necrosis factor-α, interleukin-6, interleukin-1β, glutathione peroxidise, superoxide dismutase, catalese, myeloperoxidase concentrations, immunohistochemical examinations (intracellular adhesion molecule-1), apoptosis determination, and wet/dry ratio of intestinal edema were determined.. Bupivacaine significantly decreased the cytokine, malondialdehyde, and myeloperoxidase levels and increased the antioxidant enzyme levels. Wet/dry ratio comparison showed a significant decrease in the bupivacaine (2.88±0.17) group in comparison with control (5.45±0.67) and saline (5.87±0.17) groups. The intestinal injury score was significantly decreased in rats in the epidural bupivacaine (2 [1-2]) infusion group in comparison with rats in the control (3 [2-3]) and saline (3 [2-4]) groups. Bupivacaine (63%) caused a significant decrease in the percentage of apoptotic cells in comparison with control (85%) only. ICAM-1 levels in the bupivacaine (27.4±7.1) group decreased in comparison with control (12.3±7.4) and saline (24.9±3.2) groups.. This study demonstrated that epidural bupivacaine attenuates the mesenteric I/R-related inflammatory response and intestinal damage.

Topics: Anesthesia, Epidural; Anesthetics, Local; Animals; Apoptosis; Bupivacaine; Catalase; Catheterization; Cytokines; Glutathione Peroxidase; Immunohistochemistry; Inflammation; Intercellular Adhesion Molecule-1; Intestinal Mucosa; Intestines; Lipid Peroxidation; Male; Malondialdehyde; Mesenteric Artery, Superior; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase; Thoracic Vertebrae

Ischemia-reperfusion lung injury is doubly important in thoracic surgery because of the associated ventilation damage to 1 lung. In this study we evaluated the cytoprotective effects of sevoflurane in a pulmonary autotransplant model in pigs.. Twenty Large White pigs undergoing pneumonectomy plus lung autotransplant were divided into 2 10-member groups on the basis of the anesthetic received (propofol or sevoflurane). Proinflammatory mediators, oxidative stress, nitric oxide metabolism, and hemodynamic and blood variables were measured at 5 different time points.. There was an increase of oxidative stress markers and proinflammatory mediators in the propofol group, whereas the hemodynamic variables were similar in both groups.. We demonstrated that sevoflurane decreased the inflammatory response and oxidative stress in a live ischemia-reperfusion lung model.

Topics: Anesthetics, Inhalation; Animals; Anti-Inflammatory Agents; Antioxidants; Biomarkers; Cytoprotection; Hemodynamics; Inflammation Mediators; Interleukin-1beta; Lung Injury; Lung Transplantation; Methyl Ethers; Nitric Oxide; Nitric Oxide Synthase; Oxidative Stress; Peroxidase; Pneumonectomy; Pulmonary Edema; Reperfusion Injury; Sevoflurane; Swine; Time Factors; Transplantation, Autologous; Tumor Necrosis Factor-alpha

Ischemia-reperfusion injury (IRI) is a significant factor contributing to primary graft failure in lung transplantation. Given a pivotal role of mitochondria in IRI-related molecular events, the effects of diazoxide, a selective opener of mitochondrial adenosine-5'-triphosphate (ATP)-sensitive potassium channels (mitoK(ATP)), on IRI were investigated in a rat model of lung transplantation.. The 108 rats were randomly assigned to 5 groups; a sham-operated, 2 control, and 2 experimental groups that received either diazoxide alone or a combination of diazoxide with 5-hydroxydecanoate sodium salt. Lung injuries were assessed by multiple parameters at 2 hours or 24 hours after reperfusion, including oxygenation index, wet/dry weight ratio of transplanted lungs, lung morphology, as well as measurements of myeloperoxidase, malondialdehyde, total antioxidant capacity, tumor necrosis factor-α, and interleukin-6.. Compared with the sham group, the 2 control groups revealed significant changes among most parameters of lung injury measured at either 2 hours or 24 hours after reperfusion. The extent of the changes was dramatically reduced by the administration of diazoxide. Importantly, the protective effect of diazoxide was almost completely reversed by co-administration of 5-hydroxydecanoate sodium salt, a selective blocker of mitoK(ATP).. These data provide evidence for substantial protective effects of diazoxide in an in vivo rat lung IRI model. Pharmacological modulation of mitoK(ATP) may be a potential strategy to reduce IRI-induced primary graft failure in lung transplantation.

Topics: Animals; Cytokines; Diazoxide; Lung; Lung Transplantation; Male; Malondialdehyde; Oxygen; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Vasodilator Agents

Abdominal aortic surgery can cause ischemic/reperfusion (I/R) injury not only in the lower limbs but also in remote organs such as kidneys. Venous blood volume exclusion from the inferior vena cava (phlebotomy) or/and mannitol are used as a treatment for I/R injury of kidney in humans, despite the fact that the effectiveness of these treatments is still debated. The aim of this study was to evaluate the effects of phlebotomy or/and mannitol on rat kidneys in a model of lower limbs I/R-induced acute renal injury (ARI).. Thirty male Wistar albino rats were used and divided into five groups: (I) sham-operated group, laparotomy without I/R injury (group [S], n = 6); (II) I/R group, infrarenal aortic cross-clamp was used for lower limbs I/R, 3 hours of ischemia followed by 2 hours of reperfusion (group [I/R], n = 6); (III) I/R + phlebotomy group, identical to group [I/R] except for 1 mL of blood aspiration from the inferior caval vein just after ischemia (group [P], n = 6); (IV) I/R + mannitol-treated group, these rats were subjected to I/R and received a bolus injection of mannitol (group [M], n = 6); and (V) I/R + phlebotomy + mannitol-treated group (group [P + M], n = 6), the same procedures were performed as those described for previous groups. At the end of 2-hour reperfusion, all rats were sacrificed. Both kidneys were harvested for biochemical assay (myeloperoxidase [MPO] and superoxide dismutase [SOD] activities, and malondialdehyde [MDA] and reduced glutathione levels) and for histopathological examination (tubular necrosis and acute inflammation on kidney [ARI score]).. Aortic I/R significantly increased the level of MDA (reflecting lipid peroxidation), SOD (enzymatic endogenous antioxidant), and MPO (reflecting neutrophil infiltration) activity (p < 0.05). Phlebotomy or/and mannitol treatments significantly decreased the level of MDA, SOD, and MPO activity and increased glutathione level (nonenzymatic antioxidant in the kidney tissues) (p < 0.05). Histological evaluation of ARI score showed that aortic I/R significantly increased (p value for group [S] versus group [I/R] was 0.012), whereas phlebotomy or/and mannitol treatments significantly decreased tubular necrosis and inflammatory infiltration (p values for group [I/R] versus group [P], [M], and [P + M] were 0.043, 0.043, and 0.003, respectively).. This experiment clearly indicated that the lower limbs I/R-induced ARI attenuated significantly by phlebotomy or/and mannitol treatments. Phlebotomy plus mannitol is more effective treatment than phlebotomy or mannitol alone in preventing lower limbs I/R-induced ARI in rats. Further clinical studies are required to clarify whether phlebotomy or/and mannitol treatments are beneficial in alleviating of ARI during abdominal aortic surgery.

Topics: Acute Kidney Injury; Animals; Aorta, Abdominal; Combined Modality Therapy; Constriction; Disease Models, Animal; Extremities; Glutathione; Kidney; Male; Malondialdehyde; Mannitol; Oxidative Stress; Peroxidase; Phlebotomy; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase; Time Factors

Ischemic postconditioning (IPO) has been demonstrated to attenuate ischemia/reperfusion (I/R) injury in the heart and brain, its roles to liver remain to be defined. The study was undertaken to determine if IPO would attenuate liver warm I/R injury and its protective mechanism.. Mice were divided into sham, I/R, IPO+I/R (occlusing the porta hepatis for 60 min, then treated for three cycles of 10 sec brief reperfusion consecutively, followed by a persistent reperfusion); L-NAME+ sham (L-NAME, 16 mg/kg, i.v., 5 min before repefusion); L-NAME+I/R; and L-NAME+ IPO. Blood flow of caudate and left lobe of the liver was blocked. Functional and morphologic changes of livers were evaluated. Contents of nitric oxide, eNOS and iNOS in serum were assayed. Concentration of eNOS, iNOS, malondialdehyde (MDA) and activity of superoxide dismutase (SOD) in hepatic tissue were also measured. Expressions of Akt, p-Akt and HIF-1α protein were determined by western blot. Expressions of TNF-α and ICAM-1 were measured by immunohistochemistry and RT-PCR.. IPO attenuated the dramatically functional and morphological injuries. The levels of ALT was significantly reduced in IPO+I/R group (p < 0.05). Contents of nitric oxide and eNOS in serum were increased in the IPO+I/R group (p < 0.05). IPO also up-regulated the concentration of eNOS, activity of SOD in hepatic tissue (p < 0.05), while reduced the concentration of MDA (p < 0.05). Moreover, protein expressions of HIF-1α and p-Akt were markedly enhanced in IPO+I/R group. Protein and mRNA expression of TNF-α and ICAM-1 were markedly suppressed by IPO (p < 0.05). These protective effects of IPO could be abolished by L-NAME.. We found that IPO increased the content of NO and attenuated the overproduction of ROS and I/R-induced inflammation. Increased NO contents may contribute to increasing HIF-1α level, and HIF-1α and NO would simultaneously protect liver from I/R injury. These findings suggested IPO may have the therapeutic potential through Akt-eNOS-NO-HIF pathway for the better management of liver I/R injury.

Topics: Alanine Transaminase; Animals; Gene Expression Regulation; Hypoxia-Inducible Factor 1, alpha Subunit; Intercellular Adhesion Molecule-1; Ischemic Postconditioning; Liver; Malondialdehyde; Mice; Mice, Inbred BALB C; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase; Peroxidase; Proto-Oncogene Proteins c-akt; Rats; Reperfusion Injury; Superoxide Dismutase; Tumor Necrosis Factor-alpha

The aim of the study was to investigate the effect of Ginkgo biloba extract 50 (GBE50), a well-known natural antioxidant, against immunity and antioxidant enzyme activities in ischemia reperfusion (IR) rats. Rats were then divided into six groups fed for 15 days with the same diet: three groups (IV, V, VI) were treated by different doses of GBE50 suspension [20, 40, or 60 mg/kg body weight by oral gavage every day at a fixed time (10.00 a.m.)] (equal to 5, 10 and 20 times, respectively, the maximum recommended human dose), and three groups (I, II, III) were untreated. At the end of the experiment, rats' hearts were subjected to 30 min of ischemia followed by 90 min of reperfusion. Results showed that IR significantly enhanced heart rate, S-T height, myocardium (myeloperoxidase) MPO activity and blood interleukin-8 (IL-8), tumor necrosis factor Alpha (TNF-a), interleukin-1β (IL-1β) levels, blood aspartate transaminase (AST), lactate dehydrogenase (LDH), and creatinine kinase (CK) activities, reduced myocardium sodium-potassium adenosine triphosphatase (Na(+)-K(+)-ATPase), calcium-magnesium adenosine triphosphatase (Ca(2+)-Mg(2+)-ATPase) activities and antioxidant enzyme activities in IR group (III) compared to sham control group (II). Pretreatment of GBE50 markedly significantly reduced heart rate, S-T height, myocardium MPO activity and blood IL-8, TNF-a, IL-1β levels, blood AST, LDH, and CK activities, enhanced myocardium Na(+)-K(+)-ATPase, Ca(2+)-Mg(2+)-ATPase activities and antioxidant enzyme activities in IR group (II) compared to IR group (III). The results suggested that the GBE50 may reduce the oxidative stress in the reperfused myocardium, and increased immunity and antioxidant activities in IR rats.

Topics: Adenosine Triphosphatases; Animals; Antioxidants; Aspartate Aminotransferases; Creatine Kinase; Ginkgo biloba; Heart Rate; Humans; Immunity; Interleukin-1beta; Interleukin-8; L-Lactate Dehydrogenase; Male; Peroxidase; Plant Extracts; Rats; Rats, Wistar; Reperfusion Injury; Tumor Necrosis Factor-alpha

Renal ischemia-reperfusion (I/R) may cause acute lung injury (ALI). The mortality of combined acute kidney injury and ALI is extremely high. Dexmedetomidine, an α(2) adrenergic agonist, exerts potent anti-inflammatory and organoprotective effects in addition to its sedative and analgesic properties. We sought to elucidate whether dexmedetomidine can attenuate lung injury following renal I/R in a murine model of renal I/R.. Adult C57BL/6J male mice were randomized to five groups: sham-operated control (Sham); renal I/R (I/R); intraperitoneal injection of dexmedetomidine 25 μg/kg before ischemia (pre-dex) and after perfusion (post-dex); combination of α(2) adrenergic antagonist atipamezole 250 μg/kg prior to dexmedetomidine pre-treatment (atip-dex). Kidney I/R was induced by bilateral renal pedicle clamping for 45 min and followed by 6 h reperfusion. The pulmonary tissues were harvested for histopathological evaluation, wet/dry ratio measurement, biochemical analysis of myeloperoxidase (MPO), Polymerase chain reaction (PCR) determination of Inter-cellular adhesion molecule (ICAM-1) and Tumor necrosis factor - alpha (TNF-α) mRNA.. Renal IR induced significant pulmonary injuries, increased wet/dry ratio together with the enhanced of MPO activities and increased ICAM-1 and TNF-α mRNA level. Both pre- and post-treatment with dexmedetomidine markedly reduced lung edema and inflammatory response and lowered MPO activity and ICAM-1 and TNF-α mRNA expression. The protective effects of dexmedetomidine in the lung were partially reversed by atipamezole, but there were no effect on ICAM-1 and TNF-α mRNA expression level.. Dexmedetomidine is capable of attenuating remote lung injury induced by renal IR via both α(2) adrenoceptors dependent and independent mechanisms.

Topics: Adrenergic alpha-Agonists; Adrenergic alpha-Antagonists; Animals; Depression, Chemical; Dexmedetomidine; Imidazoles; Immunohistochemistry; Intercellular Adhesion Molecule-1; Kidney Diseases; Lung Injury; Male; Mice; Mice, Inbred C57BL; Organ Size; Paraffin Embedding; Peroxidase; Real-Time Polymerase Chain Reaction; Reperfusion Injury; Tumor Necrosis Factor-alpha

To evaluate the effects of telmisartan as an antioxidant and for its tissue protective properties and to study the biochemical and histopathologic changes in experimental ischemia and ischemia/reperfusion injuries in rat ovaries.. Experimental study.. Experimental surgery laboratory in a university department.. Forty-eight female adult rats.. I: sham operation; II: bilateral ovarian ischemia; III: 3 h ischemia + 3 h reperfusion. IV and V: Rats were administered 10 and 20 mg/kg doses of telmisartan, respectively, before 0.5 h of ischemia, and then ovarian ischemia was applied; after 3 h of ischemia, the ovaries were removed. VI and VII: 3 h ovarian ischemia was applied; 2.5 h after the induction of ischemia, rats were administered the same doses of telmisartan; at the end of 3 h of ischemia, the ovaries were removed and a 3 h reperfusion followed.. Superoxide dismutase, inducible nitric oxide synthase, and myeloperoxidase activity in rat ovarian tissue; and histopathologic changes in the ovarian tissue of the rats.. Ischemia and ischemia-reperfusion increased the inducible nitric oxide synthase and myeloperoxidase activity while decreasing the super oxide dismutase activity significantly in comparison with the sham group. Before ischemia and ischemia/reperfusion, telmisartan reversed the trend in inducible nitric oxide synthase activities and the level of myeloperoxidase.. telmisartan is effective in reversing tissue damage induced by ischemia/reperfusion in ovaries.

Topics: Animals; Antioxidants; Benzimidazoles; Benzoates; Disease Models, Animal; Female; Nitric Oxide Synthase Type II; Ovary; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase; Telmisartan

The aim of this study was to investigate the possible protective effects of leflunomide, which has antioxidant and anti-inflammatory properties, against intestinal IR injury in rats.. Forty female Wistar albino rats were divided into six groups: control (n = 5), drug control (n = 7), sham operated (n = 7), IR alone (n = 7), IR plus vehicle (IR + vehicle, n = 7) and IR plus 20 mg/kg leflunomide (IR + Leflunomide, n = 7). While rats were pretreated intragastrically with leflunomide (20 mg/kg) and vehicle in three doses prior to the experiment, respectively, in the IR + Leflunomide and IR + vehicle groups, no additional application was done in the IR alone group. Intestines were exteriorized, and the superior mesenteric artery was occluded for 45 min ischemia, and then the clamp was removed for 120 min reperfusion. After the experiment, the intestines were removed for biochemical and histological examinations. Additionally, blood samples were taken for measurements of antioxidant parameters.. The intestinal IR significantly increased the MDA level and MPO activity; however, treatment with leflunomide reversed those findings (P < 0.05). The CAT activity of the IR + Leflunomide group was significantly higher than in the IR groups (P < 0.05). The SOD activity was increased in the intestinal IR group, and leflunomide treatment reversed that, too (P <0.05). The light microscopic findings showed that IR caused mucosal necrosis and leflunomide treatment reduced the morphological alterations associated with IR (P < 0.05).. Intestinal IR injury may be reversed by the anti-inflammatory and antioxidant actions of leflunomide.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Catalase; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme Inhibitors; Female; Intestinal Diseases; Intestinal Mucosa; Isoxazoles; Leflunomide; Malondialdehyde; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Treatment Outcome

Hepatic ischemia reperfusion (HIR) not only results in liver injury, but also leads to endotoxemia, which aggravates HIR-induced liver injury and dysfunction, or even causes liver failure. Taurine has been shown to protect organs from ischemia reperfusion or endotoxin by its anti-oxidant and anti-inflammatory activities. The aim of this study was to investigate whether taurine could attenuate endotoxin-induced acute liver injury after HIR. Wistar rats subjected to 30 min of hepatic ischemia followed by reperfusion and lipopolysaccharide (LPS) (0.5 mg/kg) administration, exhibited liver dysfunction (elevated serum levels of ALT, AST and LDH) and hepatic histopathological alteration. The serum levels of TNF-alpha and production of myeloperoxidase (MPO) and malondialdehyde (MDA) in liver tissues and apoptosis of hepatocytes were also increased after the combination of HIR and LPS. However, pre-administration of taurine protected livers from injury induced by the combination of HIR + LPS as the histological score, apoptotic index, MPO activity and production of MDA in liver tissues, and serum levels of AST, ALT, LDH and TNF-alpha, were significantly reduced. The expression of caspase-3, Fas and Fas ligand was upregulated in homogenates of livers from rats subjected to HIR and LPS, and this elevated expression could be inhibited by taurine. In summary, the results further emphasize the potential utilization of taurine in protecting livers against endotoxin-induced injury especially after HIR, by its anti-inflammatory, anti-oxidative and anti-apoptotic activities.

Topics: Animals; Caspase 3; Endotoxins; Injections, Intravenous; L-Lactate Dehydrogenase; Liver; Male; Malondialdehyde; Peroxidase; Protective Agents; Rats; Reperfusion Injury; Taurine

Hepatic ischemia/reperfusion (I/R) activates Kupffer cells and initiates severe oxidative stress with enhanced production of reactive oxygen species (ROS) and tumor necrosis factor-alpha (TNF-alpha). ROS and TNF-alpha mediate the expression of nuclear factors and kinases, activating the signal transduction pathway, and triggering apoptosis. The aim of our study was to evaluate the potential protective effect of (-)-epigallocatechin-3-gallate (EGCG) administration in inhibition of apoptosis by attenuating the expression of NF-kappaB, c-Jun, and caspase-3 in a model of severe hepatic I/R.. Thirty Wistar rats were allocated into three groups. Sham operation, I/R, and I/R-EGCG 50mg/kg. Hepatic ischemia was induced for 60min by Pringle's maneuver. Malondialdehyde (MDA), myeloperoxidase (MPO), light histology, scanning electron microscopy, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and immunocytochemistry for NF-kappaB, c-Jun, caspase-3, analysis on liver specimens and aspartate (AST), and alanine (ALT) transferases analysis in serum, were performed 120min after reperfusion.. Apoptosis as indicated by TUNEL and caspase-3 was widely expressed in the I/R group but very limited in the EGCG treated group. Liver was stained positive for NF-kappaB and c-Jun in the I/R group but failed to be stained positive in the EGCG treated group. MDA, MPO, AST, and ALT showed marked increase in the I/R group and significant decrease in EGCG treated group. Significant alterations of liver specimens were observed by light histology and transmission electron microscopy whilst pretreatment with EGCG resulted in parenchymal preservation.. Administration of EGCG is likely to inhibit I/R-induced apoptosis and protect liver by down-regulating NF-kappaB and c-Jun signal transduction pathways.

Topics: Alanine Transaminase; Animals; Apoptosis; Aspartate Aminotransferases; Catechin; Down-Regulation; Immunohistochemistry; In Situ Nick-End Labeling; Ischemia; Liver Diseases; Malondialdehyde; NF-kappa B; Peroxidase; Proto-Oncogene Proteins c-jun; Rats; Rats, Wistar; Reperfusion Injury

Ischemia and reperfusion (I/R) injury is characterized by significant oxidative stress, characteristic changes in the antioxidant system and organ injury leading to significant morbidity and mortality. This study was designed to assess the possible protective effect of montelukast, a selective antagonist of cysteinyl leukotriene receptor 1 (CysLT1), on hepatic I/R injury in rats. Wistar albino rats through clamping hepatic artery, portal vein, and bile duct, were subjected to 45 min of hepatic ischemia followed by 60 min reperfusion period. Montelukast (10 mg/kg; i.p.) was administered 15 min prior to ischemia and immediately before reperfusion period. At the end of the reperfusion period, the rats were killed by decapitation. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH) activity, and proinflammatory cytokines (TNF-alpha and IL-1beta) were determined in blood samples. Malondialdehyde (MDA), and glutathione (GSH) levels and myeloperoxidase (MPO) and Na+, K+-ATPase activities were determined in the liver tissue samples while formation of reactive oxygen species was monitored by using chemiluminescence (CL) technique with luminol and lucigenin probes. Tissues were also analyzed histologically. Serum ALT, AST, and LDH activities were elevated in the I/R group, while this increase was significantly decreased by montelukast treatment. Hepatic GSH levels and Na+, K+-ATPase activity, significantly depressed by I/R, were elevated back to control levels in montelukast-treated I/R group. Furthermore, increases in tissue luminol and lucigenin CL, MDA levels, and MPO activity due to I/R injury were reduced back to control levels with montelukast treatment. Since montelukast administration alleviated the I/R-induced liver injury and improved the hepatic structure and function, it seems likely that montelukast with its anti-inflammatory and antioxidant properties may be of potential therapeutic value in protecting the liver against oxidative injury due to ischemia-reperfusion.

Topics: Acetates; Animals; Cyclopropanes; Cytokines; Glutathione; Leukotriene Antagonists; Liver; Liver Diseases; Liver Function Tests; Male; Malondialdehyde; Peroxidase; Quinolines; Rats; Rats, Wistar; Reperfusion Injury; Sulfides

The possible protective effect of betulinic acid on renal ischemia/reperfusion (I/R) injury was studied. Wistar Albino rats were unilaterally nephrectomized and subjected to 45 min of renal pedicle occlusion followed by 6 h of reperfusion. Betulinic acid (250 mg/kg, i.p.) or saline was administered at 30 min prior to ischemia and immediately before the reperfusion. Creatinine, blood urea nitrogen (BUN), lactate dehydrogenase (LDH) and TNF-alpha as well as the oxidative burst of neutrophil and leukocyte apoptosis were assayed in blood samples. Malondialdehyde (MDA), glutathione (GSH) levels, Na(+), K(+)-ATPase and myeloperoxidase (MPO) activities were determined in kidney tissue which was also analysed microscopically. I/R caused significant increases in blood creatinine, BUN, LDH and TNF-alpha. In the kidney samples of the I/R group, MDA levels and MPO activity were increased significantly, however, GSH levels and Na(+), K(+)-ATPase activity were decreased. Betulinic acid ameliorated the oxidative burst response to both formyl-methionyl-leucyl-phenylalanine (fMLP) and phorbol 12-myristate 13-acetate (PMA) stimuli, normalized the apoptotic response and most of the biochemical indices as well as histopathological alterations induced by I/R. In conclusion, these data suggest that betulinic acid attenuates I/R-induced oxidant responses, improved microscopic damage and renal function by regulating the apoptotic function of leukocytes and inhibiting neutrophil infiltration.

Topics: Animals; Apoptosis; Betulinic Acid; Kidney; Leukocytes; Male; Oxidative Stress; Pentacyclic Triterpenes; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Respiratory Burst; Sodium-Potassium-Exchanging ATPase; Triterpenes

This work explored the role of inhibition of cyclooxygenases (COXs) in modulating the inflammatory response triggered by acute kidney injury.. C57Bl/6 mice were used.. Animals were treated or not with indomethacin (IMT) prior to injury (days -1 and 0).. Animals were subjected to 45 min of renal pedicle occlusion and sacrificed at 24 h after reperfusion. Serum creatinine and blood urea nitrogen, reactive oxygen species (ROS), kidney myeloperoxidase (MPO) activity, and prostaglandin E2 (PGE(2)) levels were analyzed. Tumor necrosis factor (TNF)-alpha, t-bet, interleukin (IL)-10, IL-1beta, heme oxygenase (HO)-1, and prostaglandin E synthase (PGES) messenger RNA (mRNA) were studied. Cytokines were quantified in serum.. IMT-treated animals presented better renal function with less acute tubular necrosis and reduced ROS and MPO production. Moreover, the treatment was associated with lower expression of TNF-alpha, PGE(2), PGES, and t-bet and upregulation of HO-1 and IL-10. This profile was mirrored in serum, where inhibition of COXs significantly decreased interferon (IFN)-gamma, TNF-alpha, and IL-12 p70 and upregulated IL-10.. COXs seem to play an important role in renal ischemia and reperfusion injury, involving the secretion of pro-inflammatory cytokines, activation of neutrophils, and ROS production. Inhibition of COX pathway is intrinsically involved with cytoprotection.

Topics: Acute Kidney Injury; Animals; Cyclooxygenase 1; Cyclooxygenase 2; Cyclooxygenase Inhibitors; Cytokines; Disease Models, Animal; Dose-Response Relationship, Drug; Indomethacin; Inflammation; Interleukin-10; Kidney; Male; Mice; Mice, Inbred C57BL; Peroxidase; Reactive Oxygen Species; Reperfusion Injury

The aim of this study to evaluate the effects of N-acetylcysteine (NAC) on testicular damage in a rat testicular ischemia-reperfusion (I/R) injury model.. Thirty male Wistar albino rats were divided into five groups. Group 1: sham control, Group 2: torsion (T), Group 3: torsion/detorsion (T/D), Group 4: the early NAC treatment plus T/D, 20 mg/kg of NAC was given intravenously 60 min before detorsion; Group 5: the late NAC treatment plus T/D, 20 mg/kg of NAC was given intravenously 5 min before detorsion. After torsion (2 h) and detorsion (2 h), bilateral orchiectomies were performed to determine the tissue levels of malondialdehyde (MDA) or more exactly thiobarbituric acid reactive substance (TBARS), myeloperoxidase activity and histopathological changes.. The most significant increase in the mean TBARS level and decrease in the mean seminiferous tubular diameter, germinal epithelial cell thickness values in bilateral testes were observed in T/D group rather than other groups. TBARS levels of early NAC treatment group were significantly lowered and histological parameters of spermatogenesis were significantly improved in bilateral testes when compared with T and T/D groups.. Our results suggest that the early administration of NAC may have a protective effect in the rat experimental testicular T/D models.

Topics: Acetylcysteine; Animals; Disease Models, Animal; Male; Malondialdehyde; Peroxidase; Random Allocation; Rats; Rats, Wistar; Reperfusion Injury; Spermatic Cord Torsion; Statistics, Nonparametric; Testis; Thiobarbituric Acid Reactive Substances

Pulmonary ischemia and reperfusion during routine open heart surgery with cardiopulmonary bypass can lead to pulmonary dysfunction and vasoconstriction, resulting in a high morbidity and mortality. We investigated whether ischemia/reperfusion-induced pulmonary dysfunction after full-flow cardiopulmonary bypass could be prevented by the infusion of leukocyte-depleted hypoxemic blood during the early phase of reperfusion (terminal leukocyte-depleted lung reperfusion) and whether the benefits of this method were nullified by using hyperoxemic blood for reperfusion.. Twenty-one neonatal piglets underwent 180 minutes of full-flow cardiopulmonary bypass with pulmonary artery occlusion, followed by reperfusion. The piglets were divided into 3 groups of 7 animals. In group I, uncontrolled reperfusion was achieved by unclamping the pulmonary artery. In contrast, pulmonary reperfusion was done with leukocyte-depleted hyperoxemic blood in group II or with leukocyte-depleted hypoxemic blood in group III for 15 minutes at a flow rate of 10 mL/min/kg before pulmonary artery unclamping. Then the animals were monitored for 120 minutes to evaluate post-cardiopulmonary bypass pulmonary function.. Group I developed pulmonary dysfunction that was characterized by an increased alveolar-arterial oxygen difference (204 + or - 57.7 mm Hg), pulmonary vasoconstriction, and decreased static lung compliance. Terminal leukocyte-depleted lung reperfusion attenuated post-cardiopulmonary bypass pulmonary dysfunction and vasoconstriction when hypoxemic blood was used for reperfusion (alveolar-arterial oxygen difference, 162 + or - 61.0 mm Hg). In contrast, no benefit of terminal leukocyte-depleted lung reperfusion was detected after reperfusion with hyperoxemic blood (alveolar-arterial oxygen difference, 207 + or - 60.8 mm Hg).. Reperfusion with leukocyte-depleted hypoxemic blood has a protective effect against ischemia/reperfusion-induced pulmonary dysfunction by reducing endothelial damage, cytokine release, and leukocyte activation.

Topics: Animals; Animals, Newborn; Cardiopulmonary Bypass; Endothelin-1; Interleukin-6; Leukocyte Count; Leukocyte Reduction Procedures; Leukocytes; Lung; Nitrogen Oxides; Peroxidase; Reperfusion; Reperfusion Injury; Swine; Vascular Resistance

In the present study, we tested the efficacy of treatment with the selective adenosine A2A receptor agonist 2-[p-(2-carboxyethyl)phenylethylamino]-50-ethylcarboxamidoadenosine (CGS 21680) on ischemia and reperfusion injury of the multivisceral organs. Ischemia and reperfusion injury was induced in mice by clamping both the superior mesenteric artery and the celiac artery for 30 min, followed thereafter by reperfusion. Sixty minutes after reperfusion, animals were killed for histological examination and biochemical studies. Injured vehicle-treated mice developed a significant increase of ileum TNF-alpha levels, myeloperoxidase activity, and marked histological injury and apoptosis. Ischemia and reperfusion injury of the multivisceral organs was also associated with significant mortality. Reperfused ileum sections from injured vehicle-treated mice showed positive staining for P-selectin and intercellular adhesion molecule 1. The intensity and degree of P-selectin and intercellular adhesion molecule 1 were markedly reduced in tissue sections from injured CGS 21680-treated mice. Ischemia and reperfusion-injured mice that have been treated with CGS 21680 showed also a significant reduction of neutrophil infiltration into the intestine, a reduction of apoptosis, and improved histological status of the intestine and survival. Taken together, our results clearly demonstrate that selective activation of adenosine A2A receptors plays an important role in the regulation of ischemia and reperfusion injury and results put forward the hypothesis that selective activation of adenosine A2A receptors may represent a novel and possible strategy.

Topics: Adenosine; Adenosine A2 Receptor Agonists; Animals; Apoptosis; bcl-2-Associated X Protein; Caspase 3; Fas Ligand Protein; Intercellular Adhesion Molecule-1; Intestine, Small; Male; Mice; Mitogen-Activated Protein Kinases; NF-kappa B; P-Selectin; Peroxidase; Phenethylamines; Poly Adenosine Diphosphate Ribose; Proto-Oncogene Proteins c-bcl-2; Receptor, Adenosine A2A; Reperfusion Injury; Signal Transduction; Tumor Necrosis Factor-alpha; Tyrosine

Angiotensin II contributes to the pathogenesis of inflammation induced by ischemia-reperfusion (I/R) in various organs. Angiotensin II increases vascular permeability that initiates the inflammatory process and leads to the migration of inflammatory cells into the tissue. The aim of the present study was to investigate the effect of angiotensin II on ischemia-reperfusion induced expressions of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) in rat stomachs exposed to ischemia-reperfusion.. Wistar rats were randomly separated into five groups: sham operated, I/R, I/R plus candesartan (an AT1 receptor antagonist), I/R plus PD123319 (an AT2 receptor antagonist), and I/R plus captopril (an angiotensin-converting enzyme inhibitor). Candesartan (1mg/kg/d), PD123319 (3mg/kg/d), and captopril (20mg/kg/d) were given subcutaneously twice a day for 5 d before I/R. The rats were submitted to gastric ischemia by clamping the celiac artery for 30min followed by 24h reperfusion.. Candesartan decreased the neutrophil accumulation, iNOS expression, and increased NOx level, COX-2 expression in the gastric tissue exposed to I/R compared with I/R group. PD123319 did not change the neutrophil accumulation, iNOS expression, PGE(2), or NOx levels, but increased the expression of COX-2 in the gastric tissue exposed to I/R. However, captopril did not play any role in I/R induced change in gastric mucosa.. The results suggest that Angiotensin II via angiotensin II type 1 receptor increases the accumulation of neutrophils and iNOS expression and plays a significant role in mediating inflammation in gastric mucosa exposed to I/R.

Topics: Angiotensin II; Angiotensin II Type 1 Receptor Blockers; Angiotensin II Type 2 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Animals; Benzimidazoles; Biphenyl Compounds; Captopril; Cyclooxygenase 2; Dinoprostone; Gastritis; Imidazoles; Male; Neutrophils; Nitric Oxide; Nitric Oxide Synthase Type II; Peroxidase; Pyridines; Rats; Rats, Wistar; Reperfusion Injury; Tetrazoles

Ischemia-reperfusion (I/R) injury of the kidney is a complex pathophysiological process and a major cause of acute renal failure. It has been shown that I/R injury is related to inflammatory responses and activation of apoptotic pathways. Inhibition of certain elements of inflammatory responses and apoptotic pathway seemed to ameliorate renal I/R injury. As an effective element of Panax notoginseng, NR1 has antioxidant, anti-inflammatory, antiapoptotic, and immune-stimulatory activities. Therefore, we speculate that NR1 can attenuate renal I/R injury. Ischemia-reperfusion injury was induced by renal pedicle ligation followed by reperfusion along with a contralateral nephrectomy. Male Sprague-Dawley rats were randomized to four groups: sham group, I/R control group, NR1-1 group (rats treated with NR1, 20 mg.kg.d) and NR1-2 group (rats treated with NR1, 40 mg.kg.d). All animals were killed 72 h after I/R induction. Blood and renal tissues were collected. Renal dysfunction was observed by the level of serum creatinine and histological evaluation. Apoptosis and inflammatory response in the tissue of kidney were detected mainly with molecular biological methods. NR1 attenuated I/R-induced renal dysfunction as indicated by the level of serum creatinine and histological evaluation. It prevented the I/R-induced increases in the levels of proinflammatory cytokine TNF-alpha, myeloperoxidase activity, phosphorylation of p38, and activation of nuclear factor kappaB with cell apoptosis in the kidney and enhanced expression of antiapoptosis cytokine bcl-2. Treatment with NR1 improves renal function after I/R associated with a significant reduction in cell apoptosis and inflammatory responses, which may be related to p38 and nuclear factor kappaB inhibition.

Topics: Animals; Apoptosis; Creatinine; Cytokines; Drug Evaluation, Preclinical; Drugs, Chinese Herbal; Genes, bcl-2; Ginsenosides; Kidney; Male; Neutrophils; NF-kappa B; p38 Mitogen-Activated Protein Kinases; Peroxidase; Proto-Oncogene Proteins c-bcl-2; Random Allocation; Rats; Rats, Sprague-Dawley; Renal Circulation; Reperfusion Injury

Pulmonary injury leading to early allograft dysfunction is caused by ischemia-reperfusion injury (IR) and originates from multiple pathogenic events, including endothelial damage, neutrophil extravasation into tissue, and peroxidation of cell membrane lipids, followed by pulmonary cell alterations and edema. The potent vasoconstrictor and proinflammatory mediator endothelin (ET)-1 plays a major role in this cascade. This study was conducted to determine whether treatment with relaxin, an anti-inflammatory and vasoactive hormone, prevents IR.. Isolated male Wistar rat lungs were perfused in a recirculatory model in the presence of 5-nmol/liter relaxin (n = 17) or vehicle alone (n = 14). After IR (60 minutes each) we determined wet-to-dry weight ratio, and levels of ET-1, neutrophil elastase (NE), myeloperoxidase (MPO), and malondialdehyde (MDA).. IR lungs displayed significantly elevated W/D ratios after IR compared with control lungs (p = 0.001). In the presence of relaxin, the values obtained under IR conditions were significantly reduced compared with those in the vehicle-treated IR group, but not significantly different from those obtained in the control + relaxin group (p = 0.079). The IR-stimulated increase in ET-1, NE, MPO, and MDA (3.6-, 8.4-, 6.0- and 3.0-fold over baseline, p < 0.001) was significantly reduced by relaxin (p < 0.007).. These results show that human relaxin exerts a protective effect in IR-induced lung injury, likely due to ET reduction, endothelial protection, decreased leukocyte recruitment, and hindrance of free radical-mediated tissue injury, which renders relaxin a candidate drug for lung preservation.

Topics: Animals; Endothelin-1; Endothelium; Leukocyte Elastase; Leukocytes; Lung; Lung Injury; Lung Transplantation; Male; Malondialdehyde; Models, Animal; Organ Preservation; Peroxidase; Rats; Rats, Wistar; Relaxin; Reperfusion Injury

We examined the role of cysteinyl leukotrienes (CysLTs) in the gastric ulcerogenic response to ischemia/reperfusion (I/R) in mice. Experiments were performed in male C57BL/6J mice after 18-h fasting. Under urethane anesthesia, the celiac artery was clamped for 30 min, and then reperfusion was achieved by removing the clamp. The stomach was examined for lesions 60 min thereafter. The severity of I/R-induced gastric damage was reduced by prior administration of pranlukast [CysLT receptor type 1 (CysLT(1)R) antagonist] as well as 1-[[5'-(3''-methoxy-4''-ethoxycarbonyl-oxyphenyl)-2',4'-pentadienoyl]aminoethyl]-4-diphenylmethoxypiperidine [TMK688; 5-lipoxygenase (5-LOX) inhibitor]. On the contrary, these lesions were markedly worsened by pretreatment with indomethacin, and this response was abrogated by the coadministration of TMK688 or pranlukast. The gene expression of CysLT(1)R but not 5-LOX was up-regulated in the stomach after I/R, but both expressions were increased under I/R in the presence of indomethacin. I/R slightly increased the mucosal CysLT content of the stomach, yet this increase was markedly enhanced when the animals were pretreated with indomethacin. The increased CysLT biosynthetic response to indomethacin during I/R was attenuated by TMK688. Indomethacin alone caused a slight increase of CysLT(1)R expression and markedly up-regulated 5-LOX expression in the stomach. We concluded that I/R up-regulated the expression of CysLT(1)R in the stomach; CysLTs play a role in the pathogenesis of I/R-induced gastric damage through the activation of CysLT(1)R; and the aggravation by indomethacin of these lesions may be brought about by the increase of CysLT production and the up-regulation of 5-LOX expression, in addition to the decreased prostaglandin production.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Arachidonate 5-Lipoxygenase; Chromones; Gastric Acid; Gastric Mucosa; Indomethacin; Ischemia; Leukotriene Antagonists; Leukotrienes; Male; Mice; Mice, Inbred C57BL; Peroxidase; Piperidines; Receptors, Leukotriene; Reperfusion Injury; RNA, Messenger; Stomach Ulcer

The availability of suitable lung donors has remained a significant barrier to lung transplantation. The clinical relevance of an isolated positive Gram stain in potential donor lungs, which occurs in >80%, is unclear. Low doses of lipopolysaccharide (LPS) have been protective in several models of ischemia-reperfusion injury through a pre-conditioning response. We sought to demonstrate that low-dose LPS is protective against subsequent lung ischemia-reperfusion injury.. Pathogen-free Long-Evans rats were pre-treated with vehicle or LPS 24 hours before 90 minutes of ischemia and up to 4 hours of reperfusion. Lungs were assessed for vascular permeability, myeloperoxidase content, bronchoalveolar lavage inflammatory cell and cytokine/chemokine content, as well as nuclear translocation of nuclear factor kappaB (NFkappaB) and activator protein-1 (AP-1), and interleukin-1 receptor-associated kinase-1 (IRAK-1) and stress-activated protein kinase (SAPK) activation.. Compared with positive controls, LPS pre-treatment resulted in reductions in vascular permeability (70%, p < 0.001), myeloperoxidase content (93%, p < 0.001), bronchoalveolar lavage inflammatory cells (91%, p < 0.001), and inflammatory cytokine/chemokine content (cytokine-induced neutrophil chemoattractant, 99%, p = 0.003; interleukin-1beta, 72%, p < 0.0001; tumor necrosis factor-alpha, 76%, p < 0.0001), NFkappaB (86%, p < 0.001) and AP-1 (97%, p < 0.001) nuclear translocation, and IRAK-1 (87%, p < 0.001) and SAPK (80%, p < 0.001) phosphorylation.. Lipopolysaccharide pre-treatment reduced lung injury and inflammatory mediator production after subsequent exposure to ischemia-reperfusion. Understanding the clinical significance of lipopolysaccharide in donor lungs has the potential to expand and clarify donor inclusion criteria.

Topics: Animals; Interleukin-1 Receptor-Associated Kinases; Interleukin-1beta; Ischemic Preconditioning; Lipopolysaccharides; Lung; Lung Injury; Lung Transplantation; Mitogen-Activated Protein Kinase 8; Models, Animal; NF-kappa B; Peroxidase; Rats; Rats, Long-Evans; Rats, Sprague-Dawley; Reperfusion Injury; Signal Transduction; Transcription Factor AP-1; Tumor Necrosis Factor-alpha

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

Paeoniflorin, a component in Paeonia lactiflora Pall, inhibits nuclear factor-kappaB expression in chronic hypoperfusion rat and has anti-inflammatory properties. Therefore, the aim of the present study was to investigate the effect of paeoniflorin on cerebral infarct, and the involvement of anti-inflammation. We established an animal model of cerebral infarct by occluding both the common carotid arteries and the right middle cerebral artery for 90 min, followed by reperfusion of 24 hours. The ratios of cerebral infarction area to total brain area, and neuro-deficit score were used as an index to observe the effects of paeoniflorin on cerebral infarct. ED1 (mouse anti rat CD68), interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), intercellular adhesion molecular-1 (ICAM-1), myeloperoxidase (MPO) immunostaining and apoptotic cells in the cerebral infarction region also were studied. The results indicated that both pre-treatment and post-treatment with paeoniflorin reduced the ratio of cerebral infarction area; pre-treatment with paeoniflorin also reduced the neurological deficit score. The counts of ED1, IL-1beta, TNF-alpha, ICAM-1 of microvessels and MPO immunoreactive cells and apoptotic cells were increased in the cerebral infarction region; however, these increases were reduced by Paeoniflorin pre-treatment. In conclusion, Paeoniflorin reduced cerebral infarct and neurological deficit in ischemia-reperfusion injured rats, suggesting that paeoniflorin may have a similar effect in humans and might be a suitable treatment for stroke. Paeoniflorin reduced cerebral infarct, at least in part, involves the anti-inflammatory properties.

Topics: Animals; Anti-Inflammatory Agents; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Apoptosis; Benzoates; Brain; Bridged-Ring Compounds; Cerebral Infarction; Disease Models, Animal; Glucosides; Intercellular Adhesion Molecule-1; Interleukin-1beta; Monoterpenes; Nervous System Diseases; Paeonia; Peroxidase; Phytotherapy; Plant Extracts; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

Inflammation, which is known to be detrimental to the neurological outcome during the acute phase after ischemia, provides a potential preventative or therapeutic approach for acute stroke. Lipoxins are endogenous lipoxygenase derived eicosanoids and evokes protective actions in a range of pathophysiologic processes. Here, we evaluated the efficacy of 5 (S), 6 (R)-lipoxin A(4) methyl ester (LXA(4) ME), a stable synthetic analogue of lipoxin A(4) in cerebral ischemia reperfusion injury in rats. Transient focal cerebral ischemia was induced by middle cerebral artery occlusion for 2h. Intracerebroventricular administration of LXA(4) ME immediately after onset of ischemia ameliorated neurological dysfunctions, reduced infarction volume and attenuated neuronal apoptosis. Moreover, Treatment with LXA(4) ME suppressed neutrophils infiltration and lipid peroxidation levels; inhibited the activation of microglia and astrocytes; reduced the expression of pro-inflammatory cytokines TNF-alpha and IL-1beta; and up-regulated the expression of anti-inflammatory cytokines IL-10 and TGF-beta1 in the ischemic brain. In addition, activation of NF-kappaBeta was inhibited by LXA(4) ME treatment. These results demonstrate that treatment of LXA(4) ME affords strong neuroprotective effect against cerebral ischemia reperfusion injury, and that these effects might be associated with its anti-inflammatory property.

Topics: Analysis of Variance; Animals; Apoptosis; Blotting, Western; Cytokines; Electrophoretic Mobility Shift Assay; Enzyme-Linked Immunosorbent Assay; Frontal Lobe; Immunohistochemistry; Infarction, Middle Cerebral Artery; Inflammation; Lipid Peroxidation; Lipoxins; Male; Peroxidase; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Transitory blocking of the pulmonary artery and veins is now being applied in the treatment of local advanced non-small cell lung cancer in our department. We performed this study to establish a pulmonary vessel blocking model in rabbits and investigate the features of lung ischemia-reperfusion injury.. 126 New Zealand rabbits were randomized into 3 groups: group I, sham group; group II, left pulmonary artery blocking, and group III, left pulmonary artery and veins blocking. The physiological data as well as the blood and tissue samples were harvested at the time of thoracotomy, at 1 h after ischemia and 1, 2, 4, 6 and 24 h after reperfusion, respectively. Lung injury was assessed histologically by determining the levels of malondialdehyde, superoxide dismutase, myeloperoxidase and water content.. The hemodynamics were stable in all three groups. The levels of malondialdehyde, myeloperoxidase, and water content of lung tissue were all significantly increased in groups II and III when compared with group I at 1, 2, 4 and 6 h after reperfusion. They almost all returned to baseline at 24 h after reperfusion. However, there was no significant difference observed between groups II and III at either time point. A similar change in the process of lung ischemia-reperfusion injury was observed under light and electron microscopes in group II and in group III.. The features of lung ischemia-reperfusion injury were similar when blocking the pulmonary artery and veins compared with blocking the pulmonary artery alone. Moreover, it might be safe to block the pulmonary vessels within 1 h during pulmonary surgery.

Topics: Animals; Carcinoma, Non-Small-Cell Lung; Constriction; Humans; Lung; Lung Injury; Lung Neoplasms; Microscopy, Electron, Transmission; Models, Animal; Oxidative Stress; Peroxidase; Pulmonary Artery; Pulmonary Veins; Rabbits; Reperfusion Injury; Superoxide Dismutase

Intestinal ischemia-reperfusion (I/R) injury may cause acute systemic and lung inflammation. Here, we revisited the role of TNF-alpha in an intestinal I/R model in mice, showing that this cytokine is not required for the local and remote inflammatory response upon intestinal I/R injury using neutralizing TNF-alpha antibodies and TNF ligand-deficient mice. We demonstrate increased neutrophil recruitment in the lung as assessed by myeloperoxidase activity and augmented IL-6, granulocyte colony-stimulating factor, and KC levels, whereas TNF-alpha levels in serum were not increased and only minimally elevated in intestine and lung upon intestinal I/R injury. Importantly, TNF-alpha antibody neutralization neither diminished neutrophil recruitment nor any of the cytokines and chemokines evaluated. In addition, the inflammatory response was not abrogated in TNF and TNF receptors 1 and 2-deficient mice. However, in view of the damage on the intestinal barrier upon intestinal I/R with systemic bacterial translocation, we asked whether Toll-like receptor (TLR) activation is driving the inflammatory response. In fact, the inflammatory lung response is dramatically reduced in TLR2/4-deficient mice, confirming an important role of TLR receptor signaling causing the inflammatory lung response. In conclusion, endogenous TNF-alpha is not or minimally elevated and plays no role as a mediator for the inflammatory response upon ischemic tissue injury. By contrast, TLR2/4 signaling induces an orchestrated cytokine/chemokine response leading to local and remote pulmonary inflammation, and therefore disruption of TLR signaling may represent an alternative therapeutic target.

Topics: Animals; Antibodies, Monoclonal; Chemotaxis, Leukocyte; Cytokines; Intestines; Lung; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophils; Peroxidase; Pneumonia; Reperfusion Injury; Respiratory Distress Syndrome; Toll-Like Receptor 2; Toll-Like Receptor 4; Tumor Necrosis Factor-alpha

BACKGROUND.: A neutrophil elastase (NE) inhibitor, Sivelestat, has been approved for the treatment of acute lung injury associated with systemic inflammation in humans. Some reports have also shown its protective effects in liver inflammatory states. We have recently documented the importance of NE in the pathophysiology of liver ischemia/reperfusion injury, a local Ag-independent inflammation response. This study was designed to explore putative cytoprotective functions of clinically available Sivelestat in liver ischemia/reperfusion injury. METHODS.: Partial warm ischemia was produced in the left and middle hepatic lobes of C57BL/6 mice for 90 min, followed by 6 or 24 hr of reperfusion. The mice were given Sivelestat (100 mg/kg, subcutaneous) at 10 min before ischemia, 10 min before reperfusion, and at 1 and 3 hr of reperfusion thereafter. RESULTS.: Sivelestat treatment significantly reduced serum alanine aminotransferase levels and NE activity, when compared with controls. Histological liver examination has revealed that unlike in controls, Sivelestat ameliorated the hepatocellular damage and decreased local neutrophil activity and infiltration. The expression of proinflammatory cytokines (tumor necrosis factor-alpha and interleukin-6), chemokines (CXCL-1, CXCL-2, and CXCL-10), and toll-like receptor 4 was significantly reduced in the treatment group, along with diminished apoptosis through caspase-3 pathway. Moreover, in vitro studies confirmed downregulation of proinflammatory cytokine and chemokine programs in mouse macrophage cell cultures, along with depression of innate toll-like receptor 4 signaling. CONCLUSION.: Sivelestat-mediated NE inhibition may represent an effective therapeutic option in liver transplantation and other inflammation disease states.

Topics: Animals; Chemokine CXCL1; DNA Primers; Glycine; Humans; Immunohistochemistry; Inflammation; Interleukin-6; Leukocyte Elastase; Liver; Male; Mice; Mice, Inbred C57BL; Neutrophils; Peroxidase; Polymerase Chain Reaction; Proteinase Inhibitory Proteins, Secretory; Reperfusion Injury; RNA; Sulfonamides; Tumor Necrosis Factor-alpha

In previous studies, it has been demonstrated that Nigella Sativa (NS) has protective effects against ischemia reperfusion injury on various organs. However, its protective effects on intestinal tissue against ischemia reperfusion injury are unclear. We aimed to determine whether NS prevents intestinal ischemia-reperfusion injury in rats.. Thirty rats were divided into three groups as sham (group 1), control (group 2), and NS-treatment group (group 3). All rats underwent intestinal ischemia for 60 min followed by a 60-min period of reperfusion. Rats were intraperitoneally infused only 0.9% saline solutions in group 2. Rats in the group 3 received NS (0,2 mL/kg) intraperitoneally, before ischemia and before reperfusion. Total antioxidant capacity (TAC), catalase (CAT), total oxidative status (TOS), oxidative stress index (OSI), and myeloperoxidase (MPO) in ileum tissue were measured. Also, ileum tissue histopathology was evaluated by a light microscope.. The levels of liver enzymes in group 3 were significantly lower than those in group 2 (p <.01). TAC and CAT activity levels in ileum tissue were significantly higher in group 3 than in group 2. TOS, OSI, and MPO in ileum tissue were significantly lower in group 3 than group 2 (p <.05 for TOS and MPO; p < .01 for OSI). Histological tissue damage was milder in the NS treatment group than in the control group.. Our results suggest that NS treatment protected the rat's intestinal tissue against intestinal ischemia-reperfusion injury.

Topics: Animals; Antioxidants; Catalase; Constriction; Drug Evaluation, Preclinical; Ileum; Injections, Intraperitoneal; Male; Mesenteric Artery, Superior; Nigella sativa; Oxidants; Oxidative Stress; Peroxidase; Phytotherapy; Plant Oils; Rats; Rats, Wistar; Reperfusion Injury

The aim of this study was to evaluate the effects of atorvastatin as an antioxidant and tissue protective agent and study the biochemical and histopathological changes in experimental ischemia and ischemia/reperfusion (I/R) injury in rat ovaries. The experiment used 48 adult female rats, and the experimental groups can be summarized as: group I, a sham operation; group II, a sham operation +10 mg/kg atorvastatin; group III, bilateral ovarian ischemia; and groups IV and V, bilateral ovarian ischemia +5 and 10 mg/kg atorvastatin before 30 min of ischemia, respectively (after a 3-h period of ischemia, the bilateral ovaries were surgically removed); group VI, 3-h period of ischemia followed by 3-h reperfusion; groups VII and VIII received 5 and 10 mg/kg atorvastatin, respectively, 2.5 h after the induction of ischemia, and at the end of a 3-h period of ischemia, bilateral vascular clips were removed and 3-h reperfusion continued. After the experiments, superoxide dismutase (SOD) and myeloperoxidase (MPO) activity and levels of glutathione (GSH) and lipid peroxidation (LPO) were determined, and histopathological changes were examined in all rat ovarian tissue. Ischemia and I/R increased the LPO level and MPO activity while decreasing the SOD activity and GSH level significantly in comparison to the sham group. The 5- and 10-mg/kg doses of atorvastatin before ischemia and I/R reversed the trend in LPO level and MPO activity. The levels of SOD and GSH were decreased by ischemia and I/R. The administration of atorvastatin before ischemia and I/R treatments also reversed the trend in the SOD and GSH levels. In the I/R plus atorvastatin groups, although minimal vascular dilation in the ovary stoma and some degenerative cell clusters were seen, most of the cellular structures showed no pathological changes. Administration of atorvastatin is effective in reversing tissue damage induced by ischemia and/or I/R in ovaries.

Topics: Animals; Antioxidants; Atorvastatin; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Glutathione; Heptanoic Acids; Ischemia; Lipid Peroxidation; Ovary; Peroxidase; Pyrroles; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase

A variety of stress stimuli, including ischemia-reperfusion (I/R) injury, induce the transcriptional repressor ATF3 in the kidney. The functional consequences of this upregulation in ATF3 after renal I/R injury are not well understood. Here, we found that ATF3-deficient mice had higher renal I/R-induced mortality, kidney dysfunction, inflammation (number of infiltrating neutrophils, myeloperoxidase activity, and induction of IL-6 and P-selectin), and apoptosis compared with wild-type mice. Furthermore, gene transfer of ATF3 to the kidney rescued the renal I/R-induced injuries in the ATF3-deficient mice. Molecular and biochemical analysis revealed that ATF3 interacted directly with histone deacetylase 1 (HDAC1) and recruited HDAC1 into the ATF/NF-kappaB sites in the IL-6 and IL-12b gene promoters. The ATF3-associated HDAC1 deacetylated histones, which resulted in the condensation of chromatin structure, interference of NF-kappaB binding, and inhibition of inflammatory gene transcription after I/R injury. Taken together, these data demonstrate epigenetic regulation mediated by the stress-inducible gene ATF3 after renal I/R injury and suggest potential targeted approaches for acute kidney injury.

Topics: Activating Transcription Factor 3; Acute Kidney Injury; Animals; Apoptosis; Disease Models, Animal; Epigenesis, Genetic; Histone Deacetylase 1; Interleukin-12; Interleukin-6; Mice; Mice, Inbred C57BL; Mice, Knockout; P-Selectin; Peroxidase; Reperfusion Injury; Up-Regulation

In this study we examined the effect of oral application of garlic form [garlic oil (GO)] on rats after renal ischemia-reperfusion (I/R) injury.. Forty male Wistar albino rats were divided into four groups: control, sham-operated, I/R, and I/R+GO. GO was diluted in water and administered by oral intubation three times each week for 6 weeks. All rats except sham-operated underwent 45 min of bilateral renal ischemia followed by 6 hr of reperfusion. Blood samples and kidney tissues were harvested from the rats, and then rats were killed. Serum urea, creatinine, and cystatin C levels were determined. Total antioxidant capacity (TAC), catalase (CAT), total oxidant status (TOS), oxidative stress index (OSI), myeloperoxidase (MPO), nitrite oxide (NO), and protein carbonyl (PC) levels in kidney tissue and blood were measured. In addition, kidney tissue histopathology was evaluated.. The serum urea, creatinine, and cystatin C levels were significantly higher in I/R group compared to I/R+GO group (p<0.01). The serum and tissue antioxidant markers (TAC, CAT) were significantly lower in I/R group than I/R+GO group (p<0.01). The serum oxidant markers (TOS, MPO, NO, and PC) were significantly higher in I/R group than I/R+GO group (p<0.01). Also oral application of GO was effective in decreasing of tubular necrosis score.. Based on the present data, we conclude that increased antioxidants and decreased oxidants modulated by oral application of GO attenuated the renal I/R injury.

Topics: Administration, Oral; Allyl Compounds; Animals; Antioxidants; Catalase; Creatinine; Cystatin C; Kidney; Male; Nitric Oxide; Oxidative Stress; Peroxidase; Plant Oils; Protein Carbonylation; Rats; Rats, Wistar; Reperfusion Injury; Sulfides; Urea

Topics: Animals; Brain; Brain Ischemia; Disease Models, Animal; Electroacupuncture; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Adenosine and the activation of specific adenosine receptors are implicated in the attenuation of inflammation and organ ischemia-reperfusion injury. We hypothesized that activation of A(1), A(2A), or A(3) adenosine receptors would provide protection against lung ischemia-reperfusion injury.. With the use of an isolated, ventilated, blood-perfused rabbit lung model, lungs underwent 18 hours of cold ischemia followed by 2 hours of reperfusion. Lungs were administered vehicle, adenosine, or selective A(1), A(2A), or A(3) receptor agonists (CCPA, ATL-313, or IB-MECA, respectively) alone or with their respective antagonists (DPCPX, ZM241385, or MRS1191) during reperfusion.. Compared with the vehicle-treated control group, treatment with A(1), A(2A), or A(3) agonists significantly improved function (increased lung compliance and oxygenation and decreased pulmonary artery pressure), decreased neutrophil infiltration by myeloperoxidase activity, decreased edema, and reduced tumor necrosis factor-alpha production. Adenosine treatment was also protective, but not to the level of the agonists. When each agonist was paired with its respective antagonist, all protective effects were blocked. The A(2A) agonist reduced pulmonary artery pressure and myeloperoxidase activity and increased oxygenation to a greater degree than the A(1) or A(3) agonists.. Selective activation of A(1), A(2A), or A(3) adenosine receptors provides significant protection against lung ischemia-reperfusion injury. The decreased elaboration of the potent proinflammatory cytokine tumor necrosis factor-alpha and decreased neutrophil sequestration likely contribute to the overall improvement in pulmonary function. These results provide evidence for the therapeutic potential of specific adenosine receptor agonists in lung transplant recipients.

Topics: Adenosine; Adenosine A1 Receptor Agonists; Adenosine A1 Receptor Antagonists; Adenosine A2 Receptor Agonists; Adenosine A2 Receptor Antagonists; Adenosine A3 Receptor Agonists; Adenosine A3 Receptor Antagonists; Animals; Blood Pressure; Disease Models, Animal; In Vitro Techniques; Lung; Lung Compliance; Lung Diseases; Perfusion; Peroxidase; Piperidines; Protective Agents; Pulmonary Artery; Pulmonary Edema; Rabbits; Receptor, Adenosine A1; Receptor, Adenosine A2A; Receptor, Adenosine A3; Reperfusion Injury; Tumor Necrosis Factor-alpha

The present study was to investigate the neuroprotective efficacy and mechanism of Forsythoside B. Male Sprague-Dawley rats were subjected to middle cerebral artery occlusion for 1 h followed by reperfusion for 23 h. Rats received an intravenous bolus injection of Forsythoside B at 15 min after reperfusion. The results showed that Forsythoside B at doses higher than 8 mg/kg produced a significant neuroprotective potential in cerebral ischemia and reperfusion rats. Forsythoside B (20 mg/kg) demonstrated significant neuroprotective activity even after delayed administration at 1 h, 3 h and 5 h after cerebral ischemia and reperfusion. Forsythoside B 20 mg/kg attenuated histopathological damage as demonstrated by smaller brain infarct size and brain edema, decreased cerebral Evans blue extravasation and myeloperoxidase (MPO) activity, inhibited cerebral phosphor-IkappaB-alpha and nuclear transcription factors kappaB (NF-kappaB) expression. Meanwhile, NF-kappaB expression with immunohistochemical staining was reduced, while circulating polymorphonuclear leukocytes was increased. All of these findings suggested that Forsythoside B exerted potent neuroprotective effects with a favorable therapeutic time-window, reduce of cerebral ischemia and reperfusion injury degree, attenuating blood-brain barrier (BBB) breakdown, and its protective effects may be due to inhibition of inflammatory response.

Topics: Animals; Anti-Inflammatory Agents; Antigens, Nuclear; Brain Infarction; Brain Ischemia; Caffeic Acids; Disease Models, Animal; Evans Blue; Extravasation of Diagnostic and Therapeutic Materials; Glucosides; Glycosides; Leukocytes; Male; Nerve Tissue Proteins; Neurons; Neuroprotective Agents; NF-kappa B; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Neutrophil elastase (NE) decreases the endothelial production of prostacyclin (PGI(2)) through the inhibition of endothelial nitric oxide synthase (NOS) activation and thereby contributes to the development of ischemia/reperfusion (I/R)-induced liver injury. We previously demonstrated that calcitonin gene-related peptide (CGRP) released from sensory neurons increases the insulin-like growth factor- I (IGF-I) production and thereby reduces I/R-induced liver injury. Because PGI(2) is capable of stimulating sensory neurons, we hypothesized that NE contributes to the development of I/R-induced liver injury by decreasing IGF-I production. In the present study, we examined this hypothesis in rats subjected to hepatic I/R. Ischemia/reperfusion-induced decreases of hepatic tissue levels of CGRP and IGF-I were prevented significantly by NE inhibitors, sivelestat, and L-658, 758, and these effects of NE inhibitors were reversed completely by the nonselective cyclooxygenase inhibitor indomethacin (IM) and the nonselective NOS inhibitor L-NAME but not by the selective inducible NOS inhibitor 1400W. I/R-induced increases of hepatic tissue levels of caspase-3, myeloperoxidase and the number of apoptotic cells were inhibited by NE inhibitors, and these effects of NE inhibitors were reversed by IM and L-NAME but not by 1400W. Administration of iloprost, a stable PGI(2) analog, produced effects similar to those induced by NE inhibitors. Taken together, these observations strongly suggest that NE may play a critical role in the development of I/R-induced liver injury by decreasing the IGF-I production through the inhibition of sensory neuron stimulation, which may lead to an increase of neutrophil accumulation and hepatic apoptosis through activation of caspase-3 in rats.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Calcitonin Gene-Related Peptide; Cephalosporins; Glycine; Hepatic Artery; Iloprost; Indomethacin; Insulin-Like Growth Factor I; Leukocyte Elastase; Liver; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide Synthase Type II; Peroxidase; Platelet Aggregation Inhibitors; Portal Vein; Rats; Rats, Wistar; Reperfusion Injury; Serine Proteinase Inhibitors; Sulfonamides

Treatment with inhaled carbon monoxide (CO) has been shown to ameliorate intestinal injury in experimental animals induced by lipopolysaccharide (LPS) or ischemia-reperfusion. We hypothesized that CO intraperitoneal administration (i.p.) might provide similar protection to inhaled gas. This study aimed to investigate the effects of continuous 2 L/min of 250 ppm CO i.p. on rat intestine injury induced by LPS and to try to develop a more practical means of delivering the gas.. A total of 72 male Sprague-Dawley rats were randomly assigned to 4 groups: control group, CO i.p. group, LPS group and LPS+CO i.p. group. One hour after intravenously received 5 mg/kg LPS, the rats in LPS group and LPS+CO i.p. group were exposed to room air and 2 L/min of 250 ppm CO i.p., respectively, and the rats of control group and CO i.p. group intravenously received an equal volume of 0.9% NaCl and 1 hour later, were exposed to room air and 2 L/min of 250 ppm CO i.p., respectively. One, 3 and 6 hour of each group after treated with room air or CO i.p., the animals (n = 6 for each time point) were sacrificed and intestinal tissues were collected for determinating the levels of platelet activator factor (PAF) and intercellular adhesion molecule-1 (ICAM-1) with enzyme-lined immunosorbent assays. The maleic dialdehyde (MDA) content and the myeloperoxidase (MPO) activity were determined with a chemical method. The phosphorylated p38 mitogen activated protein kinase (MAPK) expression was assayed with Western blotting and the cell apoptotic rate with flow cytometery. The arterial oxygenation was measured by blood gas analysis, and the pathology determined by light microscope.. After treatment with 2 L/min of 250 ppm CO i.p., the increase of PAF, ICAM-1, MDA, MPO, and cell apoptotic rate induced by LPS was markedly reduced (P < 0.05 or 0.01), and accompanied by ameliorating intestine injury. Western blotting showed that these effects of CO i.p. were mediated by p38 MAPK pathway. There were no significant differences in all observed parameters between control group and CO i.p. group.. The injury to the intestine via anti-oxidant, anti-inflammation and anti-apoptosis, which may involve the p38 MAPK pathway, was induced by 2 L/min of 250 ppm CO i.p. exerting potent protection against LPS.

Topics: Aldehydes; Animals; Blotting, Western; Carbon Monoxide; Flow Cytometry; Intercellular Adhesion Molecule-1; Intestinal Mucosa; Intestines; Lipopolysaccharides; Male; Microscopy; p38 Mitogen-Activated Protein Kinases; Peroxidase; Platelet Activating Factor; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Ischemic preconditioning (IPC) has been gradually introduced into clinical liver surgery and transplantation in recent years. However, the protective effects of IPC on hepatic warm ischemia/reperfusion (I/R) injury and the potential mechanisms involved are not fully understood. We aimed to evaluate whether the reduction of apoptotic sinusoidal endothelial cells (SECs), induced by IPC, contributes to its protective effect.. Male Wistar rats were randomized into three experimental groups: the continuous clamping group underwent 60 min of 70% hepatic ischemia; the IPC group received 10 min ischemia followed by 10 min reperfusion prior to ischemia, and the sham control (sham) underwent a sham operation without ischemia. Hepatocyte and SEC apoptosis, liver necrotic areas and the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), hyaluronic acid, tumor necrosis factor, myeloperoxidase (MPO) and malondialdehyde were determined. Expression of cysteine-aspartic acid protease-3 (caspase-3) in hepatocytes and SECs was also investigated. Furthermore, the hepatic leukocyte infiltration was assessed by intravital fluorescence microscopy.. IPC exhibited a significant alleviation of their postischemic liver function. Serum AST, ALT and tissue MPO were significantly decreased by IPC, and the degree of hepatocyte and SEC apoptosis was significantly inhibited, as shown by the decreased numbers of adherent leukocytes.. IPC attenuates hepatic I/R injury by the reduction of leukocyte infiltration, the reduction hepatic enzymatic leakage and the depression of apoptotic cells. SECs are more sensitive to apoptosis induced by warm I/R injury compared to hepatocytes.

Topics: Alanine Transaminase; Animals; Apoptosis; Aspartate Aminotransferases; Biomarkers; Caspase 3; Cytoprotection; Disease Models, Animal; Endothelial Cells; Hepatocytes; Hyaluronic Acid; Immunohistochemistry; In Situ Nick-End Labeling; Ischemic Preconditioning; Lipid Peroxidation; Liver; Male; Malondialdehyde; Necrosis; Neutrophil Infiltration; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Time Factors; Tumor Necrosis Factor-alpha; Warm Ischemia

We have demonstrated that therapeutic augmentation of systemic blood pressure during spinal cord ischemia plays an important role in minimizing spinal cord injury in both experimental and clinical aortic surgery. However, there remain concerns that excessively high blood pressure during spinal cord reperfusion may aggravate the reperfusion injury. The purpose of this study is to investigate the effect of high blood pressure during spinal cord reperfusion on postoperative neurologic outcomes after aortic surgery in rabbits.. Experiments were performed using a rabbit spinal cord ischemia-reperfusion model in 2 randomly divided groups: (1) In the HR group, the mean blood pressure was maintained at a high level (121 +/- 1.3 mm Hg) during reperfusion with intravenously administered phenylephrine; and (2) in the CR group, the mean blood pressure was not medically controlled (75 +/- 9.1 mm Hg) during reperfusion. Neurologic and histologic assessments and evaluation of early reperfusion injury were performed.. In the HR group, slow and incomplete recovery of transcranial motor-evoked potentials (P = .02) and low neurologic scores (P < .005) were observed during spinal cord reperfusion compared with the CR group. At 48 hours of reperfusion, there were significantly fewer viable neuron cells, more apoptosis, and more perivascular edema with gray matter vacuolation in the HR group (P < .001 for each). At 3 hours, myeloperoxidase activity (P = .0021), vascular permeability (P = .0012), and superoxide generation (P < .0001) were significantly increased in the HR group.. Excessively high blood pressure in the early phase of spinal cord reperfusion increased reperfusion injury in the spinal cord, leading to exacerbation of early-onset paraplegia. Avoidance of spinal cord reperfusion with high blood pressure may be one management strategy in thoracoabdominal aortic surgery.

Topics: Animals; Aorta; Apoptosis; Blood Pressure; Capillary Permeability; Cell Survival; Disease Models, Animal; Evoked Potentials, Motor; Motor Neurons; Neurologic Examination; Paraplegia; Peroxidase; Phenylephrine; Rabbits; Recovery of Function; Reperfusion Injury; Spinal Cord; Spinal Cord Ischemia; Superoxides; Time Factors; Vascular Surgical Procedures; Vasoconstrictor Agents

Hypothermia is widely used to mediate ischemia-reperfusion injury associated with repair of the thoracoabdominal aorta. Experiments were designed in a murine model of thoracic aortic ischemia-reperfusion (TAR) to evaluate the effect of moderate systemic hypothermia on neurologic function, spinal cord morphology, and indices of inflammation in critical organs.. C57BL/6 mice were subjected to TAR under hypothermic (34 degrees C) or normothermic (38 degrees C) conditions, followed by 24 or 48 hours of normothermic reperfusion. Neurologic functions were assessed during reperfusion. Spinal cords were examined at 24 and 48 hours after reperfusion, and the degree of injury qualified by counting the number of viable motor neurons within the anterior horns. Keratinocyte chemokine, interleukin-6, and myeloperoxidase levels were measured from lung, liver, and kidney at 24 and 48 hours.. Normothermic TAR resulted in a dense neurologic deficit in all mice throughout the reperfusion period. Mice subjected to TAR under hypothermic conditions had transient, mild neurologic deficit during the initial periods of reperfusion. Between 24 and 48 hours, delayed paralysis developed in half of these mice, whereas the other half remained neurologically intact. Spinal cord histology showed a graded degree of injury that correlated with neurologic function. There was no correlation between markers of inflammation in various organs and neurologic outcomes following TAR.. Systemic moderate hypothermia was protective against immediate paralysis after TAR in all cases and was associated with delayed paralysis in 50% of mice. This study suggests that delayed-onset paralysis may be the result of a local insult, rather than a systemic inflammatory event, precipitating spinal cord injury.

Topics: Animals; Anterior Horn Cells; Aorta, Thoracic; Cell Survival; Chemokines; Disease Models, Animal; Hypothermia, Induced; Inflammation Mediators; Interleukin-6; Kidney; Liver; Lung; Male; Mice; Mice, Inbred C57BL; Neurologic Examination; Paralysis; Peroxidase; Reperfusion Injury; Severity of Illness Index; Spinal Cord Ischemia; Time Factors

To determine whether the inhibitory action of the antiallergic cromone "mast cell stabilizing" drugs on polymorphonuclear leukocyte (PMN) trafficking is mediated through an annexin-A1 (Anx-A1) dependent mechanism.. Intravital microscopy was used to monitor the actions of cromones in the inflamed microcirculation. Reperfusion injury provoked a dramatic increase in adherent and emigrated leukocytes in the mesenteric vascular bed, associated with augmented tissue levels of myeloperoxidase. Nedocromil, 2 to 20 mg/kg, significantly (P<0.05) inhibited cell adhesion and emigration, as well as myeloperoxidase release, in wild-type but not Anx-A1(-/-) mice. Short pretreatment of human PMNs with nedocromil, 10 nmol/L, inhibited cell adhesion (P<0.05) in the flow chamber assay, and this effect was reversed by specific anti-AnxA1 or a combination of antiformyl peptide receptors 1 and 2, but not irrelevant control, antibodies. Western blotting experiments revealed that cromones stimulate protein kinase C-dependent phosphorylation and release Anx-A1 in human PMNs.. We propose a novel mechanism to explain the antiinflammatory actions of cromones on PMN trafficking, an effect that has long puzzled investigators.

Topics: Animals; Annexin A1; Anti-Allergic Agents; Anti-Inflammatory Agents; Blotting, Western; Cell Adhesion; Cells, Cultured; Cromolyn Sodium; Disease Models, Animal; Dose-Response Relationship, Drug; Endothelial Cells; Humans; Leukocyte Rolling; Male; Mesenteric Vascular Occlusion; Mice; Mice, Inbred C57BL; Mice, Knockout; Microcirculation; Microscopy, Video; Nedocromil; Neutrophils; Peritonitis; Peroxidase; Phosphorylation; Protein Kinase C; Protein Transport; Receptors, Formyl Peptide; Reperfusion Injury; Time Factors

Leukocyte recruitment is a key feature in ischemia-reperfusion (I/R)-induced tissue injury. The aim of the present study was to investigate the effect of Rho-kinase inhibition on I/R-provoked leukocyte recruitment in the colon.. C57BL/6 mice were subjected to 30 min of ischemia by clamping of the superior mesenteric artery followed by 120 min of reperfusion. Intraperitoneal pretreatment with the selective Rho-kinase inhibitors fasudil (4-40 mg/kg) and Y-27632 (1-10 mg/kg) was administered prior to induction of colonic I/R. Leukocyte-endothelium interactions were analyzed by intravital fluorescence microscopy. Colonic content of tumour necrosis factor-alpha (TNF-alpha) and the CXC chemokines macrophage inflammatory protein-2 (MIP-2) and cytokine-induced neutrophil chemoattractant (KC) were determined by ELISA. Additionally, colonic activity of myeloperoxidase (MPO), a marker of leukocyte infiltration, and malondialdehyde (MDA), were quantified.. Fasudil and Y-27632 pretreatment decreased I/R-induced leukocyte rolling and adhesion by 76% and 96%, respectively. Moreover, Rho-kinase interference reduced formation of TNF-alpha, MIP-2 and KC by more than 68% in the reperfused colon. Additionally, the reperfusion-provoked increase in the levels of MPO and MDA in the colon decreased after Rho-kinase inhibition by 69% and 42%, respectively.. Our data demonstrate that inhibition of Rho-kinase activity decrease I/R-induced leukocyte rolling, adhesion and recruitment in the colon. Moreover, these findings show that Rho-kinase signalling regulates TNF-alpha and CXC chemokine formation as well as lipid peroxidation in the reperfused colon. Thus, targeting Rho-kinase signalling may be a useful strategy in order to protect against pathological inflammation in the colon.

Topics: Animals; Cell Adhesion; Cell Movement; Chemokine CXCL1; Chemokine CXCL2; Chemokines, CXC; Colon; E-Selectin; Hemodynamics; Leukocyte Count; Leukocyte Rolling; Leukocytes; Malondialdehyde; Mice; Mice, Inbred C57BL; P-Selectin; Peroxidase; Protein Kinase Inhibitors; Reperfusion Injury; rho-Associated Kinases; Signal Transduction; Tumor Necrosis Factor-alpha

Morphine treatment for 5 days protects heart against ischemia-reperfusion (IR) injury. This study evaluated the involvement of nitric oxide (NO) in morphine-induced renal protection. Three weeks after right nephrectomy, increasing doses of morphine were administered (20-30 mg kg(-1)day(-1), 5 days) to develop dependence in rats. The left kidney underwent 45-min ischemia and 24-h reperfusion. Some rats were pretreated with naloxone (5 mg kg(-1)) or L-NAME (20 mg kg(-1)). In one group, IR was induced 24h after the last dose of morphine during the withdrawal period. Plasma nitrite/nitrate levels and serum creatinine and BUN were measured. Creatinine clearance and fractional excretion of sodium (FE(Na)) were calculated. Myeloperoxidase (MPO) activity, malondialdehyde (MDA) level, and inducible NO synthase (iNOS) expression were determined and histopathology was studied in the left kidney. IR increased serum creatinine and BUN, plasma NO (p<0.01), FE(Na), iNOS expression (p<0.001), MPO activity, MDA level, and tissue damage and decreased creatinine clearance. Morphine decreased plasma NO (p<0.05 vs IR), serum creatinine and BUN (p<0.01), FE(Na), MPO activity, MDA level, iNOS expression, and tissue damage (p<0.05), but increased creatinine clearance (p<0.05). Pretreatment with naloxone significantly increased NO production and iNOS expression in morphine-treated rats after IR (p<0.01 vs morphine dependence+IR). Pretreatment with L-NAME in morphine-treated rats decreased NO production (10.7+/-1.9, p<0.01 vs morphine dependence+IR) but could not change iNOS expression after IR. Both naloxone and L-NAME significantly abolished the protective effects of morphine dependence on functional and histological factors. The protective effect of morphine dependence on serum creatinine, BUN, FE(Na), and creatinine clearance persisted during the withdrawal period, whereas iNOS expression decreased. NO production was not decreased during the withdrawal period (p>0.1 vs morphine dependence+IR group). Morphine dependence provided renal protection in the acute phase and during withdrawal. Excessive increase or decrease in NO production abolished the effects of morphine, which suggested a role for balanced NO production and iNOS expression.

Topics: Animals; Blood Urea Nitrogen; Creatinine; Cytoprotection; Kidney; Male; Malondialdehyde; Morphine; Morphine Dependence; Naloxone; Nephrectomy; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase Type II; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Liver ischaemia and reperfusion (IR) injury is a significant clinical problem. The aim of our study was to investigate the protective effect of tumor necrosis factor-alpha (TNF-alpha) on rat liver ischaemia-reperfusion injury. A TNF-alpha dose of 3 microg/kg body weight was injected into rats that had undergone partial (70%) ischaemia and reperfusion. The activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), total blood antioxidant level (using the FRAP test), and the concentrations of TNF-alpha, myeloperoxidase (MPO) and malondialdehyde (MDA) in liver homogenates after 1, 6, and 72 hours of reperfusion were measured. It was demonstrated that, rats subjected to IR, the administration of small doses of TNF-alpha significantly reduced ALT and AST activities after 60- minute liver ischaemia and 1 or 6 hour of reperfusion. The strongest reductions in ALT and AST activities were seen after 1 hour of reperfusion (30% and 35%, respectively). Exogenous TNF-alpha reduced the release of this cytokine in all observed periods, with the greatest reduction observed after 1 hour of reperfusion. Decreases in MPO concentration (by 40-45% in all periods of observation), as a marker of hepatic neutrophil infiltration, and in MDA concentration, the end-product of lipid peroxidation (by 55-60% at all time points), accompanied the reduction of TNF-alpha release. The administration of TNF-alpha to the rats after IR did not alter total plasma antioxidant potential, as assayed by the FRAP test, after 1 hour of reperfusion; however, at the later times a marked increase (approximately 40-50%) occurred. We demonstrated that intraperitoneal injections of small doses of TNF-alpha protect rat livers from IR injury. The mechanism of this protection is related to reductions in the release of TNF-alpha during IR after injection of this cytokine, resulting in reductions in oxidative stress and inflammation during the later phase of reperfusion.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Liver; Liver Diseases; Male; Malondialdehyde; Oxidative Stress; Peroxidase; Protective Agents; Rats; Rats, Wistar; Reperfusion Injury; Tumor Necrosis Factor-alpha

Hepatic ischemia followed by reperfusion (IR) results in mild to severe remote organ injury. Oxidative stress and nitric oxide (NO) seem to be involved in the IR injury. Our aim was to investigate the effects of liver I/R on hepatic function and lipid peroxidation, leukocyte infiltration and NO synthase (NOS) immunostaining in the lung and the kidney. We randomized 24 male Wistar rats into 3 groups: 1) control; 2) 60 minutes of partial (70%) liver I and 2 hours of global liver R; and 3) 60 minutes of partial (70%) liver I and 6 hours of global liver R. Groups 2 and 3 showed significant increases in plasma alanine and aspartate aminotransferase levels and in tissue malondialdehyde and myeloperoxidase contents. In the kidney, positive endothelial NOS (eNOS) staining was significantly decreased in group 3 compared with group 1. However, staining for inducible NOS (iNOS) and neuronal NOS (nNOS) did not differ among the groups. In the lung, the staining for eNOS and iNOS did not show significant differences among the groups; no positive nNOS staining was observed in any group. These results suggested that partial liver I followed by global liver R induced liver, kidney, and lung injuries characterized by neutrophil sequestration and increased oxidative stress. In addition, we supposed that the reduced NO formation via eNOS may be implicated in the moderate impairment of renal function, observed by others at 24 hours after liver I/R.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Immunohistochemistry; Ischemia; Kidney; Lung; Male; Malondialdehyde; Neutrophils; Nitric Oxide Synthase; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

To investigate the protective role of thymoquinone (TQ) on unilateral testicular ischemia-reperfusion (I/R) injury in mice.. Experiments were performed on male C57BL/6 mice (8 weeks old, 20-25 g). The animals were divided into 3 groups including 6 mice in each group: control (sham), torsion/detorsion (TD) and TD+TQ. Mice, except the sham-operated group, were subjected to left unilateral torsion (720° rotation in the clockwise direction). The experiments were finished after sham operation time for controls, 120 min torsion and 240 min detorsion for the other groups. In the TD+TQ group 10 mg TQ was injected intraperitoneally 30 min before detorsion.. In the TD group total oxidative stress (TOS), oxidative stress index (OSI) and malondialdehyde (MDA) levels were higher than in the controls. TQ treatment decreased MDA, TOS and OSI values, but did not affect the total antioxidant capacity and myeloperoxidase activity in the TD+TQ group. Upon histological examination, mice in the TD group displayed moderate-to-severe disruption of the seminiferous epithelium. Treatment with TQ resulted in significantly reduced histological damage associated with I/R injury.. Our results suggested that TQ treatment may have a protective effect on testicular I/R injury.

Topics: Analysis of Variance; Animals; Antioxidants; Benzoquinones; Cytoprotection; Disease Models, Animal; Lipid Peroxidation; Male; Malondialdehyde; Mice; Mice, Inbred C57BL; Oxidative Stress; Peroxidase; Reperfusion Injury; Spermatic Cord Torsion; Testis; Time Factors

Ischemia-reperfusion injury is believed to be a major cause of transferred skin flap failure. Cigarette smoking is known to be associated with endogenous antioxidant depletion, hypercoagulability, and cutaneous vasoconstriction. This investigation was carried out to study possible effects of pentoxyfilline or heparin on rat skin reperfusion injury under tobacco exposure.. Thirty-six rats were randomized into two major groups: 18 were exposed to cigarette smoke during a 4 wk period prior to surgery; the remaining 18 underwent a sham smoking procedure. Each group was further divided into three equal subgroups: heparin, pentoxyfilline, and saline solution. One identical skin flap was raised in each animal. The vasculature of the flap was clamped for 3 h and reperfused for 5 min. A venous blood sample was obtained from the flap after reperfusion for serum malondialdehyde (MDA) and myeloperoxidase (MPO) analysis. Flap survival was assessed 7 d after the procedure.. The lipid peroxidation levels and flap necrosis were significantly higher in the cigarette-smoking group skin flaps. There was also a decrease of MPO activity in this group compared with the non-smoking group. Heparin-treated rats had significantly lower MDA levels and showed the most viable percent area among smoking rats.. These data suggest that heparin had a significant beneficial effect both on flap survival and on the lipid peroxidation reduction after smoke exposure in the rat axial-pattern skin flap subjected to ischemia and reperfusion injury. Pharmacologic therapy may represent an alternative way to counteract tobacco effects in flap surgery in emergency situations.

Topics: Animals; Anticoagulants; Dermatologic Surgical Procedures; Drug Therapy, Combination; Free Radical Scavengers; Heparin; Male; Malondialdehyde; Necrosis; Oxidative Stress; Pentoxifylline; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Skin; Surgical Flaps; Tobacco Smoke Pollution; Vasoconstriction

Carnosol is a phenolic diterpene that has potent antioxidant and anti-inflammatory activities. The purpose of this study was to investigate the preconditioning effects of carnosol on lung injury induced by intestinal ischemia/reperfusion (II/R).. Rats were divided into control, II/R, and carnosol groups. The II/R model was established by clamping the superior mesenteric artery for 1 h and reperfusion at 2, 4, and 6 h after ischemia. The carnosol group received 3 mg/kg carnosol intraperitoneally 1 h before the operation. The rats were then euthanized, and blood and lung specimens were obtained for analysis.. The II/R induced lung injury, characterized by histological changes and significant increasing of bronchoalveolar lavage fluid protein. The activity of lung tissue superoxide was weakened, the tissue myeloperoxidase activity and serum interleukin-6 level increased significantly in II/R groups. A strong positive expression of lung intercellular adhesion molecule-1 (ICAM-1) and nuclear factor kappa B (NF-kappaB) were observed. Pretreatment with carnosol markedly reduced lung injury by increasing the tissue superoxide activity and decreasing the myeloperoxidase activity and interleukin-6 level, which was parallel to the decreased expression of ICAM-1 and NF-kappaB.. Carnosol was able to ablate lung injury induced by II/R, partly attributed to the inhibition of NF-kappaB activation.

Topics: Abietanes; Acute Lung Injury; Animals; Bronchoalveolar Lavage Fluid; Intercellular Adhesion Molecule-1; Interleukin-6; Ischemic Preconditioning; Lung; Male; NF-kappa B; Peroxidase; Plant Extracts; Rats; Rats, Wistar; Reperfusion Injury; Rosmarinus; Superoxide Dismutase

Acute kidney injury (AKI) occurs in 30% of patients undergoing complex cardiovascular surgery, and renal ischemia-reperfusion (I/R) injury is often a contributing factor. A recent meta-analysis observed that perioperative natriuretic peptide administration was associated with a reduction in AKI requiring dialysis in cardiovascular surgery patients. This study was designed to further clarify the potential reno-protective effect of brain natriuretic peptide (BNP) using an established rat model of renal I/R injury.. The study comprised three groups (n = 10 kidneys each): (1) control (no injury); (2) I/R injury (45 min of bilateral renal ischemia followed by 3 h of reperfusion); and (3) BNP (I/R injury plus rat-BNP pretreatment at 0.01 μg/kg/min). Glomerular filtration rate (GFR) and a biomarker of AKI, urinary neutrophil gelatinase-associated lipocalin (uNGAL), were measured at baseline and at 30 minute intervals post-ischemia. Groups were compared using two-way repeated measures analysis of variance (mean ± SD, significance P < 0.05).. Baseline GFR measurements for control, I/R, and BNP groups were 1.07 ± 0.55, 0.88 ± 0.51, and 1.03 ± 0.59 mL/min (P = 0.90), respectively. Post-ischemia, GFR was significantly lower in I/R and BNP compared with controls at 30 min, 1.29 ± 0.97, 0.08 ± 0.04, and 0.06 ± 0.05 mL/min (P < 0.01), and remained lower through 3 h, 1.79 ± 0.44, 0.30 ± 0.17, and 0.32 ± 0.12 mL/min (P < 0.01). Comparing I/R to BNP groups, GFR did not differ significantly at any time point. There was no significant difference in uNGAL levels at 1 h (552 ± 358 versus 516 ± 259 ng/mL, P = 0.87) or 2 h (1073 ± 589 versus 989 ± 218 ng/mL, P = 0.79) between I/R and BNP.. BNP does not reduce the renal injury biomarker, urinary NGAL, or preserve GFR in acute renal ischemia-reperfusion injury.

Topics: Acute Disease; Acute-Phase Proteins; Animals; Biomarkers; Disease Models, Animal; Glomerular Filtration Rate; Kidney; Lipocalin-2; Lipocalins; Male; Natriuretic Peptide, Brain; Peroxidase; Proto-Oncogene Proteins; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Leucocytes play crucial roles in ischemia reperfusion injury that is inevitable in kidney transplantation. Leucocyte-depleted hemoreperfusion improved post-ischemic renal function was demonstrated in our previous study and its underlying mechanisms were further investigated in this study.. Porcine kidneys were subjected to 7 min warm ischemia and 2 h cold storage, and preserved by hemoreperfusion with or without leucocyte depletion for 6 h on an isolated organ perfusion system.. Tubulointerstitial damage was improved by leucocyte depletion, which was accompanied by reduced myeloperoxidase+ cell infiltration up to 91%. Apoptotic cells in tubular and interstitial areas were increased by hemoreperfusion, but tubular apoptosis was decreased by leucocyte depletion. The raised caspase-3 activity by hemoreperfusion was almost completely abolished by leucocyte depletion. In addition, the expression of IL-1β active subunit was enhanced by hemoreperfusion, but partially reduced by leucocyte depletion, although IL-1β precursor and HSP70 were increased by hemoreperfusion regardless of leucocyte depletion. Furthermore, myeloperoxidase+ cells were associated with caspase-3 activity, both of which were positively correlated with tubular apoptosis, IL-1β active subunit, tubulointerstitial damage, and serum creatinine, while HSP70 was linked to renal blood flow.. Leucocyte depletion improved post-ischemic renal function and structure was mainly due to reduced infiltration of myeloperoxidase+ cells, which was associated with decreased apoptosis, caspase-3 activity and IL-1β activation.

Topics: Animals; Apoptosis; Cardiopulmonary Bypass; Caspase 3; DNA Nucleotidylexotransferase; Hemoperfusion; HSP70 Heat-Shock Proteins; Interleukin-1beta; Ischemia; Kidney; Kidney Function Tests; Kidney Tubules; Leukocyte Count; Leukocyte Reduction Procedures; Organ Preservation; Peroxidase; Reperfusion Injury; Swine

Ethyl pyruvate has anti-inflammatory properties and protects organs from ischemia/reperfusion (I/R)-induced tissue injury. The aim of this study was to determine whether ethyl pyruvate decreases the inflammatory response after regional I/R injury and whether ethyl pyruvate protects against delayed regional I/R injury in an in vivo rat heart model after a 24 hours reperfusion.. Rats were randomized to receive lactated Ringer's solution or ethyl pyruvate dissolved in Ringer's solution, which was given by intraperitoneal injection 1 hour prior to ischemia. Rats were subjected to 30 min of ischemia followed by reperfusion of the left coronary artery territory. After a 2 hours reperfusion, nuclear factor κB, myocardial myeloperoxidase activity, and inflammatory cytokine levels were determined. After the 24 hours reperfusion, the hemodynamic function and myocardial infarct size were evaluated.. At 2 hours after I/R injury, ethyl pyruvate attenuated I/R-induced nuclear factor κB translocation and reduced myeloperoxidase activity in myocardium. The plasma circulating levels of inflammatory cytokines decreased significantly in the ethyl pyruvate-treated group. At 24 hours after I/R injury, ethyl pyruvate significantly improved cardiac function and reduced infarct size after regional I/R injury.. Ethyl pyruvate has the ability to inhibit neutrophil activation, inflammatory cytokine release, and nuclear factor κB translocation. Ethyl pyruvate is associated with a delayed myocardial protective effect after regional I/R injury in an in vivo rat heart model.

Topics: Animals; Anti-Inflammatory Agents; Cell Nucleus; Cytoplasm; Heart; Inflammation; Male; Myocardial Infarction; Myocardium; NF-kappa B; Peroxidase; Pyruvates; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Aortic ischemia-reperfusion (IR) is an important factor in the development of postoperative acute lung injury following abdominal aortic surgery. The aim of our study was to examine the effect of β-glucan on lung injury induced by abdominal aortic IR in rats.. Thirty-two Wistar-albino rats were randomized into four groups (eight per group) as follows: the control group (sham laparotomy), aortic IR (120 min ischemia and 120 min reperfusion), aortic IR + β-glucan (β-glucan 50 mg/kg/d for 10 d was administered orally before IR), and control + β-glucan. Lung tissue samples were obtained for biochemical analysis. Protein concentrations in bronchoalveolar lavage fluid and lung wet/dry weight ratios were measured. Histologic evaluation of the rat lung tissues was also performed.. Aortic IR significantly increased the levels of MDA, superoxide dismutase, catalase, and myeloperoxidase (P < 0.05 versus control).Whereas, β-glucan significantly decreased the lung tissue levels of MDA, superoxide dismutase, catalase, myeloperoxidase, (P < 0.05 versus aortic IR), and protein concentration in bronchoalveolar lavage fluid as well as wet/dry lung weight ratio. Histologic evaluation showed that β-glucan attenuated the morphological changes associated with lung injury.. The results of this study indicate that β-glucan attenuates lung injury induced by aortic IR in rats. We propose that this protective effect of β-glucan is due to (1) reduced systemic inflammatory response, (2) reduced oxidative stress and lipid peroxidation in the lung tissue, (3) reduced pulmonary microvascular leakage, and (4) inhibition of leukocyte infiltration into the lung tissue.

Topics: Animals; Aorta, Abdominal; beta-Glucans; Catalase; Female; Lung; Lung Injury; Male; Malondialdehyde; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase

To investigate the effect of Postcond on renal ischemia-reperfusion (I/R) injury in a canine model. I/R injury is the most common cause of renal dysfunction. Ischemic postconditioning (Postcond) is a phenomenon by which intermittent interruptions of blood flow in the early phase of reperfusion can protect organs from I/R injury.. Forty adult male mongrel dogs were randomly divided into five groups of eight dogs each. Animals underwent 60 minutes of renal pedicle occlusion followed by reperfusion for 72 hours. Postcond was performed by 15-second, 30-second, or 1-minute I/R for six or three cycles. Blood and urine were collected at different reperfusion time points (24, 48, and 72 hours), and blood urea nitrogen (BUN), creatinine (Cr) levels, urine N-acetyl-β-D-glucosaminidase (NAG), and Cr levels were assayed. Kidney samples were harvested after I/R, and renal superoxide dismutase (SOD), malondialdehyde (MDA), and myeloperoxidase (MPO) concentrations were measured, respectively. Apoptosis was evaluated by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling (TUNEL) assay in the tissue samples.. Compared with the sham group, I/R resulted in renal dysfunction, decreased SOD levels, increased MDA and MPO levels, and increased apoptosis indexes. However, Postcond attenuated the aforementioned effects, the protection of which in the Postcond of 15-second reperfusion/ischemia for six cycles was the most notable.. Postcond exerts protective effects on renal (I/R) injury. It may be a promising strategy against I/R injury in clinical practice. Its mechanisms may involve reduction of lipid peroxidation and cellular apoptosis.

Topics: Acetylglucosaminidase; Animals; Apoptosis; Blood Urea Nitrogen; Constriction; Creatinine; Dogs; In Situ Nick-End Labeling; Ischemic Postconditioning; Kidney; Lipid Peroxidation; Male; Malondialdehyde; Models, Biological; Peroxidase; Random Allocation; Reperfusion; Reperfusion Injury; Superoxide Dismutase; Warm Ischemia

To evaluate the role of leptin in the internal disorders during hepatic ischemia/reperfusion injury.. A rat model of 70% hepatic ischemia/reperfusion injury was established, with groups of sham-operation (Sham), 60 min ischemia/60 min reperfusion (I60'R60'), I60'R150', I60'R240' and I60'R360'. Serum leptin was detected by a self-produced radioimmunoassay; serum glucose, total anti-oxidation capacity, myeloperoxidase, alanine transaminase and diamine oxidase were determined by relevant kits, while histological alterations and protein levels of leptin in the lung, liver and duodenum were examined by hematoxylin-eosin staining and immunohistochemistry. Spearman's rank correlation between leptin and other variables or grading of tissue impairment were analyzed simultaneously.. Serum leptin in I60'R360' was significantly higher than in Sham and I60'R240' groups (both P < 0.05), serum glucose in I60'R360' was higher than in Sham and I60'R150' (both P < 0.05), and serum total anti-oxidation capacity in I60'R240' and I60'R360' were higher than in Sham (both P < 0.05) and I60'R150'groups (both P < 0.01). Serum myeloperoxidase in groups of I60'R240' and I60'R360' were lower than in I60'R150'group (both P < 0.05), serum alanine transaminase in the four reperfusion groups were higher than in the Sham group (all P < 0.05), while serum DAO in I60'R360' was lower than in I60'R60' (P < 0.05). Histological impairment in the lung, liver and duodenum at the early phase of this injury was more serious, but the impairment at the later phase was lessened gradually. Protein levels of leptin in the lung in the four reperfusion groups were significantly lower than in the Sham group (all P < 0.01), decreasing in the order of I60'R150', I60'R60', I60'R360' and I60'R240'; the levels in the liver in I60'R60' and I60'R240' were higher than in the Sham group (both P < 0.01), while the levels in I60'R240' and I60'R360' were lower than in I60'R60' (both P < 0.01); the levels in duodenum in I60'R240' and I60'R360' were higher than in Sham, I60'R60' and I60'R150' (all P < 0.01), while the level in I60'R150' was lower than in I60'R60' (P < 0.05). There was a significantly positive correlation between serum leptin and alanine transaminase (ρ = 0.344, P = 0.021), a significantly negative correlation between the protein level of leptin in the lung and its damage scores (ρ = -0.313, P = 0.036), and a significantly positive correlation between the protein level of leptin in the liver and its damage scores (ρ = 0.297, P = 0.047).. Endogenous leptin fluctuates in hepatic ischemia/reperfusion injury, exerts a potency to rehabilitate the internal disorders and represents a potential target for supportive therapy.

Topics: Alanine Transaminase; Amine Oxidase (Copper-Containing); Animals; Blood Glucose; Duodenum; Leptin; Liver; Lung; Male; Models, Animal; Peroxidase; Rabbits; Rats; Rats, Sprague-Dawley; Reperfusion Injury

All transplanted solid organs experience some degree of ischemia-reperfusion (I-R) injury. There is some evidence that I-R injury affects remote organs. We investigated the effects of renal I-R injury on hepatic function, cytochrome P-450 enzymes, and morphology in rats.. A rat model of 1 hour of renal ischemia followed by 1, 4, or 8 hours of reperfusion. The assays included serum alanine aminotransferase (sALT) aspartate aminotransferase (sAST), cytochrome P-450 enzymes (CYP3A, CYP2E1), hepatic glutathione S-transferase (GST), glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD), and myeloperoxidase (MPO) activities. In addition, we measured serum blood urea nitrogen (BUN) and serum creatinine (SCr), and renal MDA, glutathione peroxidase levels, and SOD activities. Morphological liver changes were observed by optical and electron microscopy.. sALT and sAST significantly increased after 1 hour of ischemia and 4 or 8 hours of reperfusion. Hepatic CYP3A and CYP2E1 activities were significantly decreased after 1 hour of ischemia and 1 or 4 hours of reperfusion. Hepatic GST, GSH, and SOD activities decreased after renal I-R, while MDA levels and MPO increased. Serum BUN and SCr levels significantly increased after reperfusion. Changes in renal MDA, GSH-px, and SOD activities were similar to those in the liver. The only difference between them was the peak time of injury: for the kidney, 8 hours, while for the liver, some changes appeared at 4 hours. Optical microscopy showed hepatic passive venous congestion and fatty degeneration as well as local necrosis. Transmission electronic microscope showed hepatic cell membrane was damaged, which seemed to explain some data results above. For example, the release of hepatic ALT and AST increased serum ALT and AST. More importantly, the release of neutrophil chemokine induced neutrophil accumulation in the liver, which could cause further damage.. Our findings indicated that hepatic function, cytochrome P-450 enzymes and morphology were affected by renal I-R injury. These effects seemed to be mediated in part by an imbalance of oxidant and antioxidant systems and recruitment of neutrophils to the liver.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Blood Urea Nitrogen; Creatinine; Cytochrome P-450 CYP2E1; Cytochrome P-450 CYP3A; Disease Models, Animal; Glutathione; Glutathione Peroxidase; Glutathione Transferase; Kidney; Liver; Liver Diseases; Male; Malondialdehyde; Microscopy, Electron, Transmission; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase; Time Factors

Recently, we reported a neuroprotective effect for Hawthorn (Crataegus oxyacantha) ethanolic extract in middle cerebral artery occlusion-(MCAO) induced stroke in rats. The present study sheds more light on the extract's mechanism of neuroprotection, especially its immunomodulatory effect.. After 15 days of treatment with Hawthorn extract [100 mg/kg, pretreatment (oral)], male Sprague Dawley rats underwent transient MCAO for 75 mins followed by reperfusion (either 3 or 24 hrs). We measured pro-inflammatory cytokines (IL-1β, TNF-α, IL-6), ICAM-1, IL-10 and pSTAT-3 expression in the brain by appropriate methods. We also looked at the cytotoxic T cell sub-population among leukocytes (FACS) and inflammatory cell activation and recruitment in brain (using a myeloperoxidase activity assay) after ischemia and reperfusion (I/R). Apoptosis (TUNEL), and Bcl-xL- and Foxp3- (T(reg) marker) positive cells in the ipsilateral hemisphere of the brain were analyzed separately using immunofluorescence.. Our results indicate that occlusion followed by 3 hrs of reperfusion increased pro-inflammatory cytokine and ICAM-1 gene expressions in the ipsilateral hemisphere, and that Hawthorn pre-treatment significantly (p ≤ 0.01) lowered these levels. Furthermore, such pre-treatment was able to increase IL-10 levels and Foxp3-positive cells in brain after 24 hrs of reperfusion. The increase in cytotoxic T cell population in vehicle rats after 24 hrs of reperfusion was decreased by at least 40% with Hawthorn pretreatment. In addition, there was a decrease in inflammatory cell activation and infiltration in pretreated brain. Hawthorn pretreatment elevated pSTAT-3 levels in brain after I/R. We also observed an increase in Bcl-xL-positive cells, which in turn may have influenced the reduction in TUNEL-positive cells compared to vehicle-treated brain.. In summary, Hawthorn extract helped alleviate pro-inflammatory immune responses associated with I/R-induced injury, boosted IL-10 levels, and increased Foxp3-positive T(regs) in the brain, which may have aided in suppression of activated inflammatory cells. Such treatment also minimizes apoptotic cell death by influencing STAT-3 phosphorylation and Bcl-xL expression in the brain. Taken together, the immunomodulatory effect of Hawthorn extract may play a critical role in the neuroprotection observed in this MCAO-induced stroke model.

Topics: Adult; Animals; bcl-X Protein; Brain; Crataegus; Cytokines; Disease Models, Animal; Encephalitis; Humans; Immunologic Factors; Infarction, Middle Cerebral Artery; Intercellular Adhesion Molecule-1; Interleukin-10; Male; Neuroprotective Agents; Peroxidase; Plant Extracts; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; STAT3 Transcription Factor; Stroke

Hepatic ischaemia-reperfusion injury (IRI) is a serious complication of liver surgery, especially extended hepatectomy and liver transplantation. Activated protein C (APC), a potent anticoagulant serine protease, has been shown to have cell-protective properties by virtue of its anti-inflammatory and anti-apoptotic activities.. The present study was designed to examine the cytoprotective effects of APC in a 60-min warm-IRI rat model.. Following a single intravenous injection of APC before reperfusion, APC exerted cytoprotective effects 4 h after reperfusion, as evidenced by: (i) decreased levels of transaminase and improved histological findings of IRI, (ii) reduced infiltration and activation of neutrophils, macrophages and T cells, (iii) reduced expression of tumour necrosis factor-alpha, (iv) reduced expression of P-selectin and intracellular adhesion molecule-1, (v) inhibited coagulation and attenuated sinusoidal endothelial cell injury, (vi) improved hepatic microcirculation and (vii) decreased transferase-mediated dUTP nick end-labelling-positive cells. These effects of APC were observed 4 h but not 24 h after reperfusion. However, multiple injections of APC after reperfusion significantly decreased the levels of transaminase and the activity of myeloperoxidase, and improved histological findings of IRI 24 h after reperfusion.. These results suggest that APC is a promising therapeutic option for hepatic warm-IRI; however, multiple injections of APC are necessary to maintain its cell-protective action over the long term.

Topics: Animals; Apoptosis; Caspase 3; Immunohistochemistry; In Situ Nick-End Labeling; Injections, Intravenous; Liver; Male; P-Selectin; Peroxidase; Protein C; Rats; Rats, Wistar; Reperfusion Injury; Time Factors; Transaminases; Tumor Necrosis Factor-alpha

The reperfusion following liver ischemia results in hepatocyte damage and apoptosis. The aim of this study was to investigate the effects of two antioxidant agents, carnosine and melatonin, in rat liver ischemia-reperfusion injury. Five study groups were formed; I. sham, II. ischemia-reperfusion, III. ischemia-reperfusion+melatonin, IV. ischemia-reperfusion+carnosine, V. ischemia-reperfusion+melatonin+carnosine. Then 250 mg/kg carnosine and 10 mg/kg melatonin were administered intraperitoneally 30 min before ischemia and immediately after the reperfusion. Sinusoidal dilatation, congestion and neutrophil infiltration were observed in the ischemia-reperfusion group while these symptoms were less pronounced in the treatment groups. Alanine aminotransferase, aspartate aminotransferase and myeloperoxidase levels were increased in the ischemia-reperfusion group while they were lowered in the treatment groups. Glutathione level was low in the ischemia-reperfusion group while it tended to increase in the ischemia-reperfusion+carnosine administered and ischemia-reperfusion+carnosine+melatonin administered groups. There was an increase in the number of apoptotic cells in the ischemia-reperfusion group while this number was lowered in the treatment groups. Carnosine was more effective than melatonin in the reversal of structural and biochemical alterations that resulted from ischemia-reperfusion injury. The administration of melatonin and carnosine together yielded better outcomes compared to the sole administration of each agent.

Topics: Alanine Transaminase; Animals; Antioxidants; Aspartate Aminotransferases; Carnosine; Female; Glutathione Transferase; Immunohistochemistry; Injections, Intraperitoneal; Liver; Melatonin; Microscopy; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Intestinal ischemia-reperfusion (II/R) induced acute lung injury is mediated by activated neutrophils and formation of free radicals. Several antioxidants have been shown to attenuate such remote organ injury. We studied the effects of zinc aspartate on lung injury induced by II/R in rats.. Twenty-four Sprague-Dawley rats were randomized into three groups. Group I was the control. Animals in Groups II and III (II/R + zinc aspartate [ZA]) underwent 60 min of ischemia and 60 min of reperfusion, respectively. Rats in Group III also received 50 mg/kg zinc aspartate before 15 min of reperfusion. Lung tissue samples and bronchoalveolar lavage fluid were obtained to assess lung tissue myeloperoxidase (MPO), adenosine deaminase (ADA), xanthine oxidase (XO), glutathione peroxidase (GPx) activities, and nitric oxide (NO), malondialdehyde (MDA) levels. Also, the levels of MDA, NO, and MPO activity were determined in bronchoalveolar lavage fluid.. Compared with the control, lung tissue MDA, NO levels, and MPO, ADA, XO activities were markedly increased (P < 0.05), whereas GPx activity significantly decreased in the II/R group (P < 0.05). However, administration of ZA significantly reversed these effects by reducing the levels of MDA, NO, and decreasing MPO, ADA, XO activities (P < 0.05). In addition, ZA significantly increased GPx activity (P < 0.05). The activity of MPO and the levels of NO and MDA were found to be higher in bronchoalveolar lavage fluid in II/R group than the control (P < 0.05). Zinc aspartate significantly diminished MPO activity and the levels of NO and MDA compared with that of control rats (P < 0.05).. Our results indicate that zinc aspartate alleviates lung injury induced by II/R attributable to its antioxidant and antiinflammatory effects.

Topics: Adenosine Deaminase; Animals; Antioxidants; Aspartic Acid; Bronchoalveolar Lavage Fluid; Disease Models, Animal; Free Radicals; Glutathione Peroxidase; Intestines; Lung; Lung Injury; Male; Neutrophils; Nitric Oxide; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Xanthine Oxidase; Zinc

Intestinal ischemia reperfusion (IR) causes tissue injury in two ways, starting a pro-inflammatory cascade and oxidative stress. The aim of this study was to investigate the possible protective effects of caffeic acid phenethyl ester (CAPE), which has antioxidant and anti-inflammatory properties, against intestinal IR injury in rats.. Forty male Wistar-Albino rats were divided into five groups: Sham, IR, IR plus ethanol (vehicle), IR plus 10 mg/kg (IR + 10CAPE), and 30 mg/kg CAPE (IR + 30CAPE) at the 30-min ischemic period. Intestines were exteriorized and the superior mesenteric artery was occluded for 45-min ischemia and then the clamp was removed for 120-min reperfusion. After the experiment, the intestines were removed for biochemical and light microscopic examinations. Additionally, blood samples were taken for plasma TNF-alpha measurement.. The TBARS levels of the IR and IR + Ethanol groups were higher than the Sham group (P < 0.05). Both CAPE treatments decreased TBARS levels in comparison with the IR group (P < 0.05). In both CAPE-treated groups, while the superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were increased compared to all other groups, which was similarly the case for the CAT activity compared to the Sham and IR + Ethanol groups (P < 0.05). There were no significant differences between GSH levels of all study groups. The TNF-alpha levels of the IR and IR + Ethanol groups were non-significantly increased compared to the Sham group (P > 0.05). The TNF-alpha levels of 10 and 30 mg/kg CAPE groups were non-significantly decreased compared to the IR group (P > 0.05). The tissue MPO activities of the IR and IR + Ethanol groups were higher than the Sham group (P < 0.05). The MPO activities of the IR + 10CAPE and IR + 30CAPE groups were not significantly different from the Sham group (P > 0.05). There was necrosis of mucosa in the IR and IR + Ethanol groups in light microscopic evaluations. Those changes were significantly reversed by 30 mg/kg CAPE treatment.. The intestinal IR injury may be reversed by anti-inflammatory and antioxidant actions of the CAPE. However, 30 mg/kg CAPE treatment may be more efficient in preventing intestinal IR injury in rats.

Topics: Animals; Antioxidants; Caffeic Acids; Catalase; Glutathione; Glutathione Peroxidase; Intestinal Diseases; Intestinal Mucosa; Jejunum; Lipid Peroxidation; Male; Malondialdehyde; Peroxidase; Phenylethyl Alcohol; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase; Tumor Necrosis Factor-alpha

The complement C5a pathway has been shown to be an important mediator of inflammation and tissue injury. To further understand the role of C5a receptor (C5aR) pathway in ischemia/reperfusion (I/R) injury, and to evaluate the potential of antagonizing C5aR to protect from I/R injury, we tested the effect of eliminating C5aR using C5aR knockout (KO) mice and their wild-type (WT) littermates in a superior mesenteric artery occlusion (SMAO) intestinal I/R injury model. C5aR KO and WT mice were subjected to SMAO or sham for 45 min. After 3 h of reperfusion, the percentage of injured ileal villi was twice as high in WT mice subjected to SMAO as compared with the C5aR KO mice. In addition, the number of neutrophils was 34% higher in WT mice subjected to SMAO as compared with the C5aR KO mice. Moreover, ileum and lung myeloperoxidase activities after SMAO were significantly higher in WT than C5aR KO mice. Apoptotic cell death was induced after reperfusion in WT-SMAO and was reduced by more than 50% in C5aR KO mice. The plasma level of TNF-alpha was increased approximately 3.74-fold in WT subjected to SMAO compared with sham. In contrast, the level was increased only approximately 1.18-fold in the C5aR KO mice subjected to SMAO. In conclusion, this study demonstrates that elimination of the C5aR pathway protects the intestine from I/R injury and diminishes intestine-derived pulmonary neutrophil sequestration. Blocking C5aR may be considered as a potential therapeutic intervention for I/R injury.

Topics: Animals; Apoptosis; Disease Models, Animal; Ileum; Intestinal Mucosa; Lung; Mice; Mice, Knockout; Neutrophil Infiltration; Peroxidase; Receptor, Anaphylatoxin C5a; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; Tumor Necrosis Factor-alpha

Plasma factor XIII (FXIII) is responsible for stabilization of fibrin clot at the final stage of blood coagulation. Because FXIII has also been shown to modulate inflammation and endothelial permeability, we hypothesized that FXIII diminishes multiple organ dysfunction caused by gut I/R injury. A model of superior mesenteric artery occlusion (SMAO) was used to induce gut I/R injury. Rats were subjected to 45-min SMAO or sham SMAO and treated with recombinant human FXIII A2 subunit (rFXIII) or placebo at the beginning of the reperfusion period. Lung permeability, lung and gut myeloperoxidase activity, gut histology, neutrophil respiratory burst, and microvascular blood flow in the liver and muscles were measured after a 3-h reperfusion period. The effect of activated rFXIII on transendothelial resistance of human umbilical vein endothelial cells was tested in vitro. Superior mesenteric artery occlusion-induced lung permeability as well as lung and gut myeloperoxidase activity was significantly lower in rFXIII-treated versus untreated animals. Similarly, rFXIII-treated rats had lower neutrophil respiratory burst activity and ileal mucosal injury. Rats treated with rFXIII also had higher liver microvascular blood flow compared with the placebo group. Superior mesenteric artery occlusion did not cause FXIII consumption during the study period. In vitro, activated rFXIII caused a dose-dependent increase in human umbilical vein endothelial cell monolayer resistance to thrombin-induced injury. Thus, administration of rFXIII diminishes SMAO-induced multiple organ dysfunction in rats, presumably by preservation of endothelial barrier function and the limitation of polymorphonuclear leukocyte activation.

Topics: Animals; Cell Membrane Permeability; Enzyme Activation; Factor XIII; Gastrointestinal Tract; Humans; Lung; Male; Mesenteric Artery, Superior; Microcirculation; Multiple Organ Failure; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Regional Blood Flow; Reperfusion Injury; Respiratory Burst

This study investigated the effects of glycyrrhizin, a potent antioxidant, on tissue injury caused by ischemia/reperfusion (I/R) of the gut.. I/R injury of the intestine was caused by clamping both the superior mesenteric artery and the celiac trunk for 45 min followed by release of the clamp allowing reperfusion for 1 or 6 h.. Administration of glycyrrhizin, significantly reduced the (a) fall of mean arterial blood pressure, (b) mortality rate, (c) myeloperoxidase (MPO) activity, (d) production of pro-inflammatory cytokines [tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta)], (e) histological evidence of gut injury, (f) immunoreactivity of nitrotyrosine, (g) poly ADP-ribose (PAR) formation, (h) the expression of ICAM-1 and P-selectin, (i) activation of nuclear factor-kappaB (NF-kappaB) and (j) signal transducer and activator transcription-3 (STAT-3) induced by splanchnic artery occlusion-reperfusion shock.. This study demonstrates that glycyrrhizin exerts multiple protective effects in splanchnic artery occlusion-reperfusion shock.

Topics: Animals; Anti-Inflammatory Agents; Electroencephalography; Gastrointestinal Tract; Glycyrrhizic Acid; Hypertension; Immunohistochemistry; Intercellular Adhesion Molecule-1; Interleukin-1beta; Male; Malondialdehyde; Neutrophils; P-Selectin; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

Neutrophil activation and tissue sequestration are crucial events in intestinal ischemia-reperfusion injury, but their role in the gut wall after clinical cardiopulmonary bypass (CPB) remains unclear. We tested whether local post-CPB inflammatory response in the gut wall would be associated with intestinal mucosal perfusion.. Twenty pigs underwent 60 min of aortic clamping and 75 min of normothermic perfusion. Intestinal biopsies were taken after 120 min of reperfusion. Based on ileal myeloperoxidase activity (MPO), the animals were divided into 2 groups, CPB-induced increase in MPO (MPO+) versus no such increase (MPO-), for comparison of the parameters that measure gut mucosal perfusion. Ileal p(CO)((2)) and intramucosal pH were determined, and arterial gases were analyzed. Additionally, several hemodynamic parameters and blood thrombin-antithrombin complexes (TAT) were measured.. Myocyte degeneration, endothelial activation and vasculitis were more pronounced in the MPO+ group (p < 0.05), while the MPO- group showed significantly increased pi(CO)((2)) and lower mucosal pH values during reperfusion. Hemodynamics and TAT levels did not differ between the groups.. Tissue sequestration of neutrophils was poorly associated with perturbed mucosal perfusion after CPB. Mechanisms of gut wall injury after a low-flow/reperfusion setting can differ from those in reperfusion injury after total ischemia.

Topics: Animals; Cardiopulmonary Bypass; Female; Hemodynamics; Hydrogen-Ion Concentration; Intestines; Ischemia; Male; Neutrophil Activation; Peroxidase; Reperfusion Injury; Sus scrofa

Administration of Na(+)/H(+) exchange isoform-1 (NHE-1) inhibitors before ischemia has been shown to attenuate myocardial infarction in several animal models of ischemia-reperfusion injury. However, controversy still exists as to the efficacy of NHE-1 inhibitors in protection of myocardial infarction when administered at the onset of reperfusion. Furthermore, the efficacy of NHE-1 inhibition in protection of skeletal muscle from infarction (necrosis) has not been studied. This information has potential clinical applications in prevention or salvage of skeletal muscle from ischemia-reperfusion injury in elective and trauma reconstructive surgery. The objective of this research project is to test our hypothesis that the NHE-1 inhibitor cariporide is effective in protection of skeletal muscle from infarction when administered at the onset of sustained ischemia or reperfusion and to study the mechanism of action of cariporide. In our studies, we observed that intravenous administration of cariporide 10 min before ischemia (1 or 3 mg/kg) or reperfusion (3 mg/kg) significantly reduced infarction in pig latissimus dorsi muscle flaps compared with the control, when these muscle flaps were subjected to 4 h of ischemia and 48 h of reperfusion (P < 0.05; n = 5 pigs/group). Both preischemic and postischemic cariporide treatment (3 mg/kg) induced a significant decrease in muscle myeloperoxidase activity and mitochondrial-free Ca(2+) content and a significant increase in muscle ATP content within 2 h of reperfusion (P < 0.05; n = 4 pigs/group). Preischemic and postischemic cariporide treatment (3 mg/kg) also significantly inhibited muscle NHE-1 protein expression within 2 h of reperfusion after 4 h of ischemia, compared with the control (P < 0.05; n = 3 pigs/group). These observations support our hypothesis that cariporide attenuates skeletal muscle infarction when administered at the onset of ischemia or reperfusion, and the mechanism involves attenuation of neutrophil accumulation and mitochondrial-free Ca(2+) overload and preservation of ATP synthesis in the early stage of reperfusion.

Topics: Adenosine Triphosphate; Animals; Calcium; Castration; Disease Models, Animal; Drug Administration Schedule; Enzyme Inhibitors; Guanidines; Infarction; Injections, Intravenous; Mitochondria, Muscle; Muscle, Skeletal; Necrosis; Neutrophil Infiltration; Neutrophils; Peroxidase; Reperfusion Injury; Sodium-Hydrogen Exchangers; Sulfones; Surgical Flaps; Swine; Time Factors

Erythropoietin (Epo) was recently defined as an endogenous agent with more than hematopoietic functions. Previously we explored the potential of this agent to ameliorate lung ischemia-reperfusion (I/R) injury. The present study aims to determine the optimal dose and timing of administration for improving lung injury, and to further investigate the mechanisms by which Epo ameliorates lung I/R injury. The left lungs of Sprague-Dawley rats underwent 90 min ischemia and 120 min reperfusion. Firstly, animals in different groups were intraperitoneally injected with various doses of recombined human erythropoietin (rhEpo) 24 h prior to operation, 2 h prior to operation, or after the onset of reperfusion. Pulmonary myeloperoxidase (MPO) activity and malondialdehyde (MDA) content were evaluated. Treatment with 3 KU/kg rhEpo 2 h prior to operation was optimal for attenuating pulmonary MPO activity and MDA content. With such treatment, ultrastructural changes of pneumocytes were observed, and the pneumocyte apoptosis index was also determined by terminal dUTP nick-end labeling method. The plasma concentrations of tumor necrosis factor (TNF)-alpha and matrix metalloproteinase (MMP)-9 were evaluated by enzyme-linked immunosorbent assay, and pulmonary expression by immunohistochemistry. When pretreated with rhEpo, the pneumocyte ultrastructure was predominantly maintained and the pulmonary apoptosis index was markedly reduced. In comparison with untreated animals, in treated animals the plasma concentrations of TNF-alpha and MMP-9 were significantly decreased, and their expression in lung tissue was markedly reduced as well. The results indicated that Epo potently protected against lung I/R injury by inhibiting systemic and local expression of TNF-alpha and MMP-9.

Topics: Animals; Apoptosis; Dose-Response Relationship, Drug; Erythropoietin; Gene Expression Regulation; Lung Injury; Male; Malondialdehyde; Matrix Metalloproteinase 9; Peroxidase; Pulmonary Alveoli; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Time Factors; Tumor Necrosis Factor-alpha

The pathogenesis of gastric mucosal injury is a multifaceted process involving reactive oxygen and nitrogen species, both of which play a crucial role in the ischemia/reperfusion model of gastric damage. Hence, several studies have evaluated the anti-ulcerogenic effect of metal chelators, antioxidative enzymes, and low-molecular-weight antioxidants. Low molecular weight superoxide dismutase (SOD) mimetics have been shown to play a protective role against oxidative damage. Therefore, the aim of the current study was to investigate the modulatory effect of 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl [TEMPOL (50 mg/kg)], a SOD mimetic, and the SOD inhibitor, diethyldithiocarbamate [DETCA (100 mg/kg)] on gastric lesions induced by ischemia/reperfusion. This insult produced typical gastric lesions, a significant fall in the gastric mucosal glutathione (GSH) and nitric oxide (NO) levels, accompanied by an increase in malondialdehyde (MDA) content and myeloperoxidase (MPO) activity. TEMPOL markedly minimized gastric ulceration and restored MDA, NO, and MPO levels, but did not alter GSH level, which dropped drastically in DETCA treated group, an effect that was not reflected on gross lesions induced by ischemia/reperfusion. In conclusion, TEMPOL can confer protection from gastric ischemia/reperfusion injury possibly by reducing the level of superoxide anion (O(2)(*-)), replenishing NO, and minimizing neutrophil infiltration. Therefore, specific SOD mimetics could be beneficial as complementary agents in the management of gastric ulceration.

Topics: Animals; Cell Membrane Permeability; Cyclic N-Oxides; Estradiol; Free Radical Scavengers; Gastric Mucosa; Glutathione; Male; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Spin Labels; Superoxide Dismutase; Superoxides

The aim of this experimental study was to investigate the early effects of interleukin-10 (IL-10) and interleukin-1beta antagonist (anti-IL-1beta) against cellular damage, inflammatory reactivity, lipid peroxidation (LPO), and myeloperoxidase (MPO) activity induced by spinal cord ischemia reperfusion injury (IRI).. Thirty-two single strain female Albino rats were divided into four groups: control (sham-operated), IRI-alone, IL-10-treated (100 mug/kg), and anti-IL-1beta-treated (1 mg/kg) groups after IRI. IRI was induced by balloon occlusion of the aorta and simultaneous hypovolemia during occlusion. The animals were sacrificed at 24 h. Histopathological and ultrastructural analyses, biochemical studies for determination of LPO and MPO activity and Comet assays (single cell electrophoresis for detecting DNA single strand breaks) were performed in all study groups.. Compared with the levels of control (sham-operated) animals, IRI produced a significant increase in the levels of LPO and MPO activity, and prominent tissue damage characterized by leukocyte infiltration, edema and neuronal and glial damage in the affected spinal cord in 24 h. The administration of IL-10 decreased LPO and MPO activity, and suppressed initial inflammatory response in the first 24 h. The effects of anti-IL-1beta were limited to decrease in LPO activity without considerable evidence of cellular preservation.. These data suggest that systemic administration of IL-10 attenuates the early ischemic response, and may restrict the tissue damage in the first 24 h after spinal cord ischemia reperfusion injury. Anti-IL-1beta has no considerable effect in this time window. The results of this preliminary study promote further studies with longer time windows on the effects of anti-inflammatory cytokines in spinal cord IRI.

Topics: Animals; DNA Fragmentation; Endothelium; Female; Interleukin-10; Interleukin-1beta; Lipid Peroxidation; Malondialdehyde; Neurons; Peroxidase; Rats; Rats, Mutant Strains; Reperfusion Injury; Spinal Cord Ischemia; Treatment Outcome

Tourniquet use is a common tool in surgical procedures of the limbs. Hydroxyethyl starch (HES) 130/0.4 not only has a role in replacement of the liquid deficits due to trauma, bleeding or shock, but it is also effective in enhancing tissue oxygen tension and regulation of microcirculation. The aim of this study was to investigate how 6% HES 130/0.4 affects ischaemia and reperfusion in skeletal muscle.. An ischaemia/reperfusion model (3 and 2 h, respectively) was applied in 14 rabbits. Group S (n = 7) was infused with 0.9% NaCl (0.2 ml kg(-1) min(-1)) and group HES was infused with 6% HES 130/0.4 (0.2 ml kg(-1) min(-1)). The total liquid was divided into equal one-thirds and given in the preischaemia, ischaemia and reperfusion phases. Ketamine HCl (30 mg kg(-1)) was used for anaesthesia, and blood pressure, pulse and blood gases were monitored. Muscle biopsies were taken in the preischaemic (A), ischaemic (B) and reperfusion (C) phases. In these samples, nitrite, nitrate, reduced glutathione (GSH) and myeloperoxidase (MPO) were measured to assess oxidative stress elements, and malondialdehyde (MDA) was measured to assess lipid peroxidation. Repeated variance analysis, Mann-Whitney U test and Student's t test were used for statistical analysis of these parameters.. In group S, the MPO levels were significantly increased in the reperfusion phase compared with baseline, whereas there was a decrease in MPO levels in the reperfusion period in the HES group. This difference between groups was statistically significant (P = 0.011).. The results of this study showed that 6% HES 130/0.4 solution is more effective in the prevention of ischaemia/reperfusion injury than saline when given in the same volume.

Topics: Animals; Disease Models, Animal; Hydroxyethyl Starch Derivatives; Muscle, Skeletal; Peroxidase; Rabbits; Reperfusion Injury

Prostaglandin I2 (PGI2) produced by endothelial cells improves ischemia/reperfusion-induced acute renal injury by inhibiting leukocyte activation in rats. However, the underlying mechanism(s) of increased PGI2 production is not fully understood. Activation of sensory neurons increases endothelial PGI2 production by releasing calcitonin gene-related peptide (CGRP) in rats with hepatic ischemia or reperfusion. We examined here whether activation of sensory neurons increases PGI2 endothelial production, thereby reducing ischemia/reperfusion-induced acute renal injury.. Anesthetized rats were subjected to 45 min of renal ischemia/reperfusion. Rats were pretreated with CGRP, capsazepine (a vanilloid receptor-1 antagonist), CGRP(8-37) (a CGRP receptor antagonist), or indomethacin (a cyclooxygenase inhibitor), or subjected to denervation of primary sensory nerves before ischemia/reperfusion.. Renal tissue levels of CGRP and 6-keto-prostaglandin F1alpha, a stable metabolite of PGI2, increased after renal ischemia/reperfusion, peaking at 1 h after reperfusion. Overexpression of CGRP was also noted at 1 h after reperfusion. Increases in renal tissue levels of 6-keto-prostaglandin F1alpha at 1 h after reperfusion were significantly inhibited by pretreatment with capsazepine, CGRP(8-37), and indomethacin. Pretreatment with capsazepine, CGRP(8-37), indomethacin, and denervation of primary sensory nerves significantly increased blood urea nitrogen and serum creatinine levels, renal vascular permeability, renal tissue levels of myeloperoxidase activity, cytokine-induced neutrophil chemoattractant, and tumor necrosis factor-alpha, and decreased renal tissue blood flow. However, pretreatment with CGRP significantly improved these changes.. Our results suggest activation of sensory neurons in the pathologic process of ischemia/reperfusion-induced acute renal injury. Such activation reduces acute renal injury by attenuating inflammatory responses through enhanced endothelial PGI2 production.

Topics: 6-Ketoprostaglandin F1 alpha; Acute Disease; Animals; Anti-Inflammatory Agents, Non-Steroidal; Calcitonin Gene-Related Peptide; Calcitonin Gene-Related Peptide Receptor Antagonists; Capillary Permeability; Capsaicin; Chemokine CCL2; Denervation; Immunohistochemistry; Indomethacin; Kidney; Kidney Diseases; Male; Peptide Fragments; Peroxidase; Rats; Rats, Wistar; Renal Circulation; Reperfusion Injury; Sensory Receptor Cells; TRPV Cation Channels; Tumor Necrosis Factor-alpha

Urinary trypsin inhibitor (UTI) inhibits the inflammatory response and protects against ischemia-reperfusion (I/R) injury. The inflammatory response is mediated by nuclear factor-kappa B (NF-kappaB) and its related target genes and products such as vascular endothelial cell adhesion molecule and CXC chemokines. We aimed to assess the roles of those mediators in a UTI-treated mouse model of hepatic I/R injury.. Treatment group 1 (UTI given 5 minutes prior to liver ischemia), treatment group 2 (UTI given 5 minutes after the anhepatic phase) and a control group were investigated. Blood and liver samples were obtained and compared at 1, 3, 6 and 24 hours after reperfusion.. Attenuation of pathological hepatocellular damage was greater in the treatment groups than in the control group (P<0.05). Compared with the control group, the UTI treatment groups showed significantly lower serum alanine aminotransferase and aspartate aminotransferase levels, decreased myeloperoxidase activity, and reduced NF-kappaB activation. Also downregulated was the expression of tumor necrosis factor-alpha, cytokine-induced neutrophil chemoattractant, and macrophage inflammatory protein-2 at the mRNA level. P-selectin protein and intercellular adhesion molecule-1 protein expression were also downregulated. In addition, the treatment group 1 showed a better protective effect against I/R injury than the treatment group 2.. UTI reduces NF-kappaB activation and downregulates the expression of its related mediators, followed by the inhibition of neutrophil aggregation and infiltration in hepatic I/R injury. The protective role of UTI is more effective in prevention than in treatment.

Topics: Acute-Phase Reaction; Alanine Transaminase; Animals; Aspartate Aminotransferases; Chemokine CXCL1; Chemokine CXCL2; Disease Models, Animal; Down-Regulation; E-Selectin; Glycoproteins; Intercellular Adhesion Molecule-1; Liver Diseases; Mice; Mice, Inbred BALB C; Neutrophils; NF-kappa B; P-Selectin; Peroxidase; Reperfusion Injury; RNA, Messenger; Tumor Necrosis Factor-alpha

Even though renal hypoxia is believed to play a pivotal role in the development of acute kidney injury, no study has specifically addressed the alterations in renal oxygenation in the early onset of renal ischemia-reperfusion (I/R). Renal oxygenation depends on a balance between oxygen supply and consumption, with the nitric oxide (NO) as a major regulator of microvascular oxygen supply and oxygen consumption. The aim of this study was to investigate whether I/R induces inducible NO synthase (iNOS)-dependent early changes in renal oxygenation and the potential benefit of iNOS inhibitors on such alterations. Anesthetized Sprague-Dawley rats underwent a 30-min suprarenal aortic clamping with or without either the nonselective NO synthase inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME) or the selective iNOS inhibitor L-N(6)-(1-iminoethyl)lysine hydrochloride (L-NIL). Cortical (CmicroPo(2)) and outer medullary (MmicroPo(2)) microvascular oxygen pressure (microPo(2)), renal oxygen delivery (Do(2ren)), renal oxygen consumption (Vo(2)(ren)), and renal oxygen extraction (O(2)ER) were measured by oxygen-dependent quenching phosphorescence techniques throughout 2 h of reperfusion. During reperfusion renal arterial resistance and oxygen shunting increased, whereas renal blood flow, CmicroPo(2), and MmicroPo(2) (-70, -42, and -42%, respectively, P < 0.05), Vo(2)(ren), and Do(2ren) (-70%, P < 0.0001, and -28%, P < 0.05) dropped. Whereas L-NAME further decreased Do(2ren), Vo(2)(ren), CmicroPo(2), and MmicroPo(2) and deteriorated renal function, L-NIL partially prevented the drop of Do(2ren) and microPo(2), increased O(2)ER, restored Vo(2)(ren) and metabolic efficiency, and prevented deterioration of renal function. Our results demonstrate that renal I/R induces early iNOS-dependent microvascular hypoxia in disrupting the balance between microvascular oxygen supply and Vo(2)(ren), whereas endothelial NO synthase activity is compulsory for the maintenance of this balance. L-NIL can prevent ischemic-induced renal microvascular hypoxia.

Topics: Animals; Enzyme Inhibitors; Hypoxia; Kidney; Lysine; Microcirculation; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase Type II; Oxygen Consumption; Peroxidase; Rats; Rats, Sprague-Dawley; Renal Circulation; Reperfusion Injury; Sodium

Systemic inflammatory response syndrome, as a consequence of ischemia/reperfusion (I/R), negatively influences the function of the affected organs. The objective of this study was to assess the role of nitric oxide (NO) in remote intestinal inflammatory response elicited by hindlimb I/R. To this end, C57BL/6 (wild type; WT) and inducible nitric-oxide synthase (iNOS)-deficient mice were subjected to bilateral hindlimb ischemia (1 h) followed by 6 h of reperfusion. Some WT mice were injected with iNOS inhibitor N-[3-(aminomethyl)benzyl] acetamidine (1400W) (5 mg/kg s.c.) immediately before reperfusion, and proinflammatory response was assessed 6 h later. Hindlimb I/R resulted in dysfunction of the small intestine as assessed by the increase in permeability [blood-to-lumen clearance of Texas Red-dextran (molecular mass 3 kDa)] and an increase in the luminal levels of tumor necrosis factor (TNF)-alpha protein and nitrate/nitrite (NO(2)(-)/NO(3)(-)). The above-mentioned changes were accompanied by up-regulation of the proinflammatory phenotype in the mucosa of small intestine with respect to 1) an increase in TNF-alpha and iNOS protein expression, 2) leukocyte accumulation, 3) formation of edema, 4) an increase in leukocyte rolling/adhesion in the submucosal microvasculature, and 5) activation of transcription factor nuclear factor-kappaB and up-regulation of adhesion molecule expression. Interestingly, the most profound changes with respect to intestinal dysfunction were found in jejunum and ileum, whereas duodenum was affected the least. Interfering with iNOS activity (1400W and iNOS-deficient mice) significantly attenuated hindlimb I/R-induced inflammatory response and dysfunction of the small intestine with respect to the above-mentioned markers of inflammation. The obtained results indicate that hindlimb I/R induces remote inflammatory response in the small intestine through an iNOS-derived NO-dependent mechanism.

Topics: Amidines; Animals; Benzylamines; E-Selectin; Enzyme Inhibitors; Epithelial Cells; Hindlimb; Inflammation; Intercellular Adhesion Molecule-1; Intestinal Mucosa; Intestine, Small; Leukocytes; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Microvessels; NF-kappa B; Nitrates; Nitric Oxide; Nitric Oxide Synthase Type II; Nitrites; Permeability; Peroxidase; Reperfusion Injury; Tumor Necrosis Factor-alpha

Prolonged ischemia amplified iscehemia/reperfusion (IR) induced renal apoptosis and autophagy. We hypothesize that ischemic conditioning (IC) by a briefly intermittent reperfusion during a prolonged ischemic phase may ameliorate IR induced renal dysfunction. We evaluated the antioxidant/oxidant mechanism, autophagy and apoptosis in the uninephrectomized Wistar rats subjected to sham control, 4 stages of 15-min IC (I15 x 4), 2 stages of 30-min IC (I30 x 2), and total 60-min ischema (I60) in the kidney followed by 4 or 24 hours of reperfusion. By use of ATP assay, monitoring O2-. amounts, autophagy and apoptosis analysis of rat kidneys, I60 followed by 4 hours of reperfusion decreased renal ATP and enhanced reactive oxygen species (ROS) level and proapoptotic and autophagic mechanisms, including enhanced Bax/Bcl-2 ratio, cytochrome C release, active caspase 3, poly-(ADP-ribose)-polymerase (PARP) degradation fragments, microtubule-associated protein light chain 3 (LC3) and Beclin-1 expression and subsequently tubular apoptosis and autophagy associated with elevated blood urea nitrogen and creatinine level. I30 x 2, not I15 x 4 decreased ROS production and cytochrome C release, increased Manganese superoxide dismutase (MnSOD), Copper-Zn superoxide dismutase (CuZnSOD) and catalase expression and provided a more efficient protection than I60 against IR induced tubular apoptosis and autophagy and blood urea nitrogen and creatinine level. We conclude that 60-min renal ischemia enhanced renal tubular oxidative stress, proapoptosis and autophagy in the rat kidneys. Two stages of 30-min ischemia with 3-min reperfusion significantly preserved renal ATP content, increased antioxidant defense mechanisms and decreased ischemia/reperfusion enhanced renal tubular oxidative stress, cytosolic cytochrome C release, proapoptosis and autophagy in rat kidneys.

Topics: Aldehydes; Animals; Antioxidants; Apoptosis; Autophagy; Blood Urea Nitrogen; Creatinine; Cysteine Proteinase Inhibitors; Cytochromes c; Female; Ischemic Preconditioning; Isoenzymes; Kidney; NADPH Oxidases; Nephrectomy; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reactive Oxygen Species; Reperfusion Injury; Superoxide Dismutase

There is evidence demonstrating the protective effect of cGMP-specific phosphodiesterase type 5 (PDE5) inhibitors against ischemic injury in certain tissues. In this study, sildenafil, a potent inhibitor of PDE5, was tested for its beneficial effects in the prevention of disrupted ileal contractility and damage to tissue caused by intestinal ischemia-reperfusion in rats. Male Sprague-Dawley rats were divided into four groups: sham-operated; sham-operated with sildenafil pretreatment; ischemia-reperfusion with vehicle pretreatment; and ischemia-reperfusion with sildenafil pretreatment. The superior mesenteric artery was occluded for 45 min to induce ischemia. The clamp was then removed for a 60 min period of reperfusion. Sildenafil (1 mg/kg, i.v.) or saline was administered prior to the surgical procedure in the ischemia-reperfusion and sham-operated groups. Isometric contractions of the ileal segments in response to acetylcholine or electrical field stimulation (120 V, 2 ms pulse for 5 s, 1-20 Hz) were recorded. Additionally, levels of thiobarbituric acid reactive substances and myeloperoxidase activity were measured in addition to a histopathological examination of the ileal tissue. The contractions induced by both acetylcholine and electrical field stimulations were markedly inhibited after ischemia-reperfusion. Sildenafil pretreatment (1 mg/kg, i.v.) abolished the inhibition of responses to acetylcholine. The increased levels of thiobarbituric acid reactive substances and myeloperoxidase activity caused by ischemia-reperfusion were reversed to control levels with sildenafil pretreatment. Intestinal ischemia-reperfusion caused severe ischemic injury in rat ileum, which was prevented by sildenafil. These results suggest that sildenafil pretreatment has a protective effect against ileal dysfunction and damage induced by intestinal ischemia-reperfusion in the rat.

Topics: Acetylcholine; Animals; Dose-Response Relationship, Drug; Electric Stimulation; Ileum; Intestinal Mucosa; Isometric Contraction; Lipid Peroxidation; Male; Microelectrodes; Muscle Contraction; Neutrophils; Perfusion; Peroxidase; Phosphodiesterase Inhibitors; Piperazines; Purines; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sildenafil Citrate; Sulfones; Thiobarbituric Acid Reactive Substances; Vasodilator Agents

Renal injury induced by aortic ischemia-reperfusion (IR) is an important factor in the development of postoperative acute renal failure following abdominal aortic surgery. Endothelin (ET) is involved in the development of renal injury induced by aortic IR and tezosentan (R0 61-0612) is a specific ET receptor antagonist. The aim of this study was to examine the effect of tezosentan on renal injury induced by abdominal aortic IR in rats.. Twenty-four Wistar-Albino rats were randomized into three groups (eight per group). Control group underwent laparotomy and dissection of the infrarenal abdominal aorta (IAA) without occlusion. The aortic IR group underwent laparotomy and clamping of the IAA for 120 min followed by 120 min of reperfusion. Aortic IR + tezosentan group underwent same aortic IR periods, and received a bolus intravenous injection of 10 mg/kg tezosentan before ischemia plus continuous intravenous infusion of 1 mg/kg/h tezosentan during 120 min ischemia and 120 min reperfusion. At the end of the experiment, blood and kidney tissue specimens were obtained for biochemical analysis. Histological evaluation of the rat kidney tissues was also done.. Biochemical analysis showed that aortic IR significantly increased (P < 0.05 versus control) while tezosentan significantly decreased (P < 0.05 versus aortic IR) the tissue levels of malondialdehyde, superoxide dismutase, catalase and myeloperoxidase. Histological analyses showed that aortic IR significantly increased (P < 0.05 versus control) while tezosentan significantly decreased (P < 0.05 versus aortic IR) focal glomerular necrosis, dilatation of Bowman's capsule, degeneration of tubular epithelium, necrosis in tubular epithelium and tubular dilatation in the renal tissue samples.. The results of this study indicate that tezosentan reduces renal injury induced by aortic IR in rats. We think that tezosentan exerted this beneficial effect via reducing oxidative stress and lipid peroxidation, inhibition of leukocyte infiltration into renal tissue and acting cytoprotective on renal tubular cells after aortic IR.

Topics: Acute Kidney Injury; Animals; Aorta, Abdominal; Aortic Diseases; Catalase; Endothelin Receptor Antagonists; Female; Kidney Glomerulus; Lipid Peroxidation; Male; Malondialdehyde; Necrosis; Oxidative Stress; Peroxidase; Postoperative Complications; Pyridines; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase; Tetrazoles; Vasodilator Agents

A previous study has shown that brief period of repetitive superior mesenteric artery (SMA) occlusion and reperfusion applied at the onset of reperfusion, ischemic postconditioning (IPo), attenuates intestinal injury after intestinal ischemia/reperfusion (II/R). This study tested the hypothesis that IPo would attenuate II/R-induced acute lung injury, which is comparable to ischemic preconditioning (IPC) and the brief period of postconditioning applied at the onset of reperfusion is critical to pulmonary protection by IPo.. Rat II/R injury was produced by clamping SMA for 60 min followed by 60 min of reperfusion. The rats were randomly allocated into one of five groups based upon the intervention (n = 8): sham operation (Sham): sham surgical preparation including isolation of the SMA without occlusion was performed; Injury: there was no intervention either before or after SMA occlusion; ischemia preconditioning (IPC): the SMA was occluded for 10 min followed by 10 min of reperfusion before prolonged occlusion; ischemia postconditioning (IPo): three cycles of 30 sec reperfusion-30 sec reocclusion were imposed immediately upon reperfusion (3 min total intervention); delayed postconditioning: clamping was completely released for full reperfusion for 3 min (the duration of the IPo algorithm), after which three cycles of 30 sec occlusion and reperfusion were applied.. Histologic results showed severe damage in rat lungs in the injury group evidenced by increased lung wet/dry weight ratio and pulmonary permeability index, which was accompanied by increases in the levels of plasma TNFalpha and IL-6, the pulmonary malondialdehyde (MDA), and the pulmonary myeloperoxidase (MPO) activity and a decrease in superoxide dismutase (SOD) activity. IPo, not delayed IPo, could significantly attenuate lung injury and improve the above variables, which was comparable to IPC.. IPo at onset of reperfusion reduces acute lung injury induced by II/R, which may be mediated, in part, by inhibiting oxidant generation, neutrophils filtration, and proinflammatory mediators releases. The early period of reperfusion in the rat model is critical to pulmonary protection by IPo. IPo may improve outcome in clinical conditions associated with II/R.

Topics: Acute Lung Injury; Animals; Blood Pressure; Extravascular Lung Water; Interleukin-6; Intestines; Ischemic Preconditioning; Lung; Male; Malondialdehyde; Mesenteric Artery, Superior; Mesenteric Vascular Occlusion; Organ Size; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase; Tumor Necrosis Factor-alpha

Nuclear factor (NF)-kappaB participates in ischemia/reperfusion (I/R) hepatic signaling, stimulating both protective mechanisms and the generation of inflammatory cytokines. After analyzing NF-kappaB activation during increasing times of ischemia in murine I/R, we observed that the nuclear translocation of p65 paralleled Src and IkappaB tyrosine phosphorylation, which peaked after 60 minutes of ischemia. After extended ischemic periods (90 to 120 minutes) however, nuclear p65 levels were inversely correlated with the progressive induction of oxidative stress. Despite this profile of NF-kappaB activation, inflammatory genes, such as tumor necrosis factor (TNF) and interleukin (IL)-1beta, predominantly induced by Kupffer cells, increased throughout time during ischemia (30 to 120 minutes), whereas protective NF-kappaB-dependent genes, such as manganese superoxide dismutase (Mn-SOD), expressed in parenchymal cells, decreased. Consistent with this behavior, gadolinium chloride pretreatment abolished TNF/IL-1beta up-regulation during ischemia without affecting Mn-SOD levels. Interestingly, specific glutathione (GSH) up-regulation in hepatocytes by S-adenosylmethionine increased Mn-SOD expression and protected against I/R-mediated liver injury despite TNF/IL-1beta induction. Similar protection was achieved by administration of the SOD mimetic MnTBAP. In contrast, indiscriminate hepatic GSH depletion by buthionine-sulfoximine before I/R potentiated oxidative stress and decreased both nuclear p65 and Mn-SOD expression levels, increasing TNF/IL-1beta up-regulation and I/R-induced liver damage. Thus, the divergent role of NF-kappaB activation in selective liver cell populations underlies the dichotomy of NF-kappaB in hepatic I/R injury, illustrating the relevance of specifically maintaining NF-kappaB activation in parenchymal cells.

Topics: Animals; Apoptosis; Blotting, Western; Cell Nucleus; Glutathione; Hepatocytes; I-kappa B Proteins; Interleukin-1beta; Kupffer Cells; Lipid Peroxidation; Liver Diseases; Male; Mice; Mice, Inbred C57BL; NF-kappa B; NF-KappaB Inhibitor alpha; Oxidative Stress; Peroxidase; Phosphorylation; Protein Transport; Reactive Oxygen Species; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Superoxide Dismutase; Tumor Necrosis Factor-alpha; Tyrosine

Hydrogen gas was reported to reduce reactive oxygen species and alleviate cerebral, myocardial and hepatic ischemia/reperfusion (I/R) injuries. This paper studied the effect of hydrogen-rich saline, which was easier for clinical application, on the intestinal I/R injury. Model of intestinal I/R injury was induced in male Sprague-Dawley rats. Physiological saline, hydrogen-rich saline or nitrogen-rich saline (5 ml/kg) was administered via intravenous infusion at 10 min before reperfusion, respectively. The intestine damage was detected microscopically and was assessed by Chiu score system after I/R injury. In addition, serum DAO activity, TNF-alpha, IL-1beta and IL-6 levels, tissue MDA, protein carbonyl and MPO activity were all increased significantly by I/R injury. Hydrogen-rich saline reduced these markers and relieved morphological intestinal injury, while no significant reduction was observed in the nitrogen-rich saline-treated animals. In conclusion, hydrogen-rich saline protected the small intestine against I/R injury, possibly by reduction of inflammation and oxidative stress.

Topics: Animals; Cytokines; Hydrogen; Inflammation; Inflammation Mediators; Infusions, Intravenous; Intestinal Mucosa; Intestines; Male; Malondialdehyde; Neutrophils; Nitrogen; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sodium Chloride

Adiponectin (APN), a circulating adipose-derived hormone regulating inflammation and energy metabolism, has beneficial actions on cardio- and cerebrovascular disorders. Hypoadiponectinemia is associated with ischemic cerebrovascular disease, however, little is known about the cerebroprotective action of APN as well as its molecular mechanisms. In the present study, the role of APN in the pathogenesis of acute cerebral injury was investigated. Rats were divided into three groups: (i) a sham operation group; (ii) an ischemia/reperfusion (I/R) group, rats were subjected to 1 h middle cerebral artery occlusion followed by 23 h reperfusion (I/R); (iii) a APN-treated group, two bolus of 5 microg APN was administered through jugular vein before and after operation. I/R resulted in obvious cerebral infarct size, neurological deficits, and increased expression of endogenous immunoglobin G and matrix metalloproteinase 9, which can be significantly diminished by administration of APN. We also found that APN can significantly inhibited cerebral expression of myeloperoxidase, a distinct indicator of inflammatory cell infiltration, and inflammatory cytokines, interleukin (IL)-1beta, tumor necrosis factor-alpha and IL-8 in response to I/R, suggesting that APN exerts potent anti-inflammatory actions. Furthermore, nuclear factor (NF)-kappaB (p65), a critical transcription factor involved in inflammatory reactions, was observed predominantly located in the nucleus after I/R, whereas APN can obviously inhibit its translocation from cytoplasm into the nucleus. Results of this study demonstrate that APN exerts a potent cerebroprotective function through its anti-inflammatory action, and NF-kappaB (p65) is a key component in this process. APN might be potential molecular targets for ischemic stroke therapy.

Topics: Active Transport, Cell Nucleus; Adiponectin; Animals; Anti-Inflammatory Agents; Brain Ischemia; Cytokines; Cytoprotection; Disease Models, Animal; Encephalitis; Immunoglobulin G; Infarction, Middle Cerebral Artery; Injections, Intravenous; Male; Matrix Metalloproteinase 9; Neuroprotective Agents; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Transcription Factor RelA

Enzymatic activity inhibition of CD26/dipeptidylpeptidase IV (CD26/DPP IV) attenuated short-term post-Tx (transplantation) ischemia-reperfusion injury after 18-hr-ischemia. Here, we investigated the effect of intragraft CD26/DPP IV catalytic inhibition on primary graft dysfunction during 7 day post-Tx, following extended ischemia.. A syngeneic rat (LEW [Lewis abstract]) orthotopic lung Tx model was used, grafts exposed to 18 hr cold ischemia before Tx. Controls were flushed and preserved in Perfadex, and harvested after 1 day (CON1) or 7 day (CON7) post-Tx. Investigational groups IN1, IN3, and IN7 grafts were perfused with and stored in Perfadex + inhibitor (AB192) and harvested at 1, 3, and 7 days post-Tx, respectively. Blood gas analysis, peak airway pressure (PAwP), wet/dry weight ratio, myeloperoxidase thiobarbituric acid reactive substances (TBARS), and staining for vasoactive intestinal peptide (VIP) were analyzed.. IN1 versus CON1 showed preserved histology, increased pO2 (P<0.01), lowered PAwP (P<0.01), less edema (P<0.05) and decreased TBARS (P<0.05). Survival was better for IN7 versus CON7 (P<0.01). The course of AB192-perfused grafts from 1 to 7 days displayed improved values for pO2 (P<0.01), PAwP (P<0.01), edema (P<0.05), TBARS (P<0.05), and myeloperoxidase (P<0.05). Compared with controls, VIP was preserved during 18 hr ischemia in alveolar macrophages (P=0.0001) and respiratory epithelial cells (P=0.001).. Perfusion with an inhibitor of CD26/DPP IV enzymatic activity significantly reduced the incidence and severity of pulmonary primary graft dysfunction and enabled recovery after extended ischemia. This is the first report that CD26/DPPIV inhibitor treatment increases local pulmonary VIP levels, which correlate with preserved ventilatory function and pulmonary structural integrity.

Topics: Animals; Dipeptidyl Peptidase 4; Dipeptidyl-Peptidase IV Inhibitors; Follow-Up Studies; Graft Survival; Heparin; Lung Transplantation; Melatonin; Perfusion; Peroxidase; Rats; Rats, Inbred Lew; Reperfusion Injury; Survival Analysis; Thiobarbituric Acid Reactive Substances; Transplantation, Isogeneic; Vasoactive Intestinal Peptide

The ischemia/reperfusion (I/R) represents a common pathological mechanism that causes renal injuries. A monosaccharide D-allose has been shown to inhibit neutrophil activation, which is involved in the I/R-induced organ injuries. We therefore examined the role of D-ribose in the I/R-induced renal injury using a rat model. D-ribose, a monosaccharide found in all living cells, serves as a key component of adenosine-5'-triphosphate and nicotinamide adenine dinucleotide. Male Wistar rats were divided into the sham, control and D-ribose groups. In the control and D-ribose groups, rats were subjected to 45 min of left renal ischemia, followed by 24 h of reperfusion, while the I/R procedure was not performed in the sham group. Rats were intravenously administered D-ribose (sham group and D-ribose group, 400 mg/kg) or saline (control group) 30 min before ischemia. Blood urea nitrogen (BUN), serum creatinine and urinary N-acetyl beta-D-glucosaminidase (NAG) were measured as indicators of glomerular function and proximal tubular function. We also measured cytokine-induced neutrophil chemoattractant-1 (CINC-1) and myeloperoxidase concentrations to assess neutrophil activation and infiltration, respectively. The tissue sections were scored to evaluate the tubular injury. In the control group, BUN, creatinine, NAG, CINC-1, myeloperoxidase, histological severity score, and number of infiltrating neutrophils were increased following I/R insult, as compared with the sham group. Such increases in biochemical markers, severity score, and infiltrating neutrophils were significantly inhibited in the D-ribose group. Thus, D-ribose ameliorates the I/R-induced renal injury probably by inhibiting neutrophil activation, and may be useful in attenuating the renal injury associated with renal ischemia.

Topics: Animals; Chemokine CXCL1; Kidney; Male; Neutrophil Activation; Neutrophils; Peroxidase; Random Allocation; Rats; Rats, Wistar; Reperfusion Injury; Ribose

Ischemia reperfusion injury (IRI) is a problem in organ transplantation. Relaxin is known to have a protective effect against liver injury caused by IRI. Using a model of isolated perfused rat liver, the local oxygen supply in liver tissue was investigated by spectrophotometric in vivo imaging and compared to the protective effect of relaxin shown by immunohistochemical measurement of myeloperoxidase and malonyldialdehyde activities as determinants of oxidative stress. In relaxin-treated liver tissue, spectrophotometry showed a better oxygen supply and decreased myeloperoxidase and malonyldialdehyde activities. Our data suggest that relaxin can influence the oxygen distribution in liver tissue and reduce cell damage caused by IRI.

Topics: Animals; Liver; Liver Transplantation; Male; Malondialdehyde; Organ Preservation Solutions; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Relaxin; Reperfusion Injury; Spectrophotometry

Cinnamophilin (CINN, (8R, 8'S)-4, 4'-dihydroxy-3, 3'-dimethoxy-7-oxo-8, 8'-neolignan) protects against ischemic stroke in mice. While some anti-oxidative effects of CINN have been characterized, its therapeutic window and molecular basis for neuroprotection remain unclear. We evaluated antioxidant and anti-inflammatory properties and therapeutic window of CINN against brain ischemia using a panel of in vitro and in vivo assays. Data from lipid peroxidation and radical scavenging assays showed that CINN was a robust antioxidant and radical scavenger. CINN effectively inhibited the production of tumor necrosis factor alpha (TNF-alpha), nitrite/nitrate, interleukin-6 (IL-6) in lipopolysaccharide (LPS)-stimulated RAW 264.7 and BV2 cells (P<0.05, respectively). Relative to controls, CINN, administrated at 80 mg/kg, 2, 4, or 6 h postinsult, but not 12 h, significantly reduced brain infarction by 34-43% (P<0.05) and improved neurobehavioral outcome (P<0.05) following transient focal cerebral ischemia in rats. CINN (10-30 microM) also significantly reduced oxygen-glucose deprivation-induced neuronal damage (P<0.05) in rat organotypic hippocampal slices, even when it was administrated 2, 4, or 6 h postinsult. Together, CINN protects against ischemic brain damage with a therapeutic window up to 6 h in vivo and in vitro, which may, at least in part, be attributed by its direct antioxidant and anti-inflammatory effects.

Topics: Analysis of Variance; Animals; Animals, Newborn; Antioxidants; Benzothiazoles; Body Weight; Cell Line, Transformed; Disease Models, Animal; Dose-Response Relationship, Drug; Glucose; Guaiacol; Hippocampus; Hypoxia; Interleukin-6; Ischemic Attack, Transient; Lignans; Lipid Peroxidation; Microglia; Nitrates; Nitrites; Organ Culture Techniques; Peroxidase; Phenethylamines; Polysaccharides; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sulfonic Acids; Time Factors; Tumor Necrosis Factor-alpha

Nuclear factor kappaB (NF-kappaB) has been found to be critical to the pathogenesis of renal ischemia-reperfusion injury (IRI). Using small interfering RNA (siRNA) to silence the expression of RelB, a component of the transcription factors Rel/nuclear factor kappaB, may protect renal IRI. Here, we report an siRNA-based treatment of preventing IRI.. Renal IRI was induced in mice by clamping the left renal pedicle for 25 or 35 min. The therapeutic effects of siRNA were evaluated in renal function, histologic examination, and overall survival after lethal IRI.. A single injection of RelB siRNA resulted in knockdown of renal RelB expression. In comparison with control mice, levels of blood urea nitrogen and serum creatinine were significantly decreased in mice treated with siRNA. Pathologic examination demonstrated that tissue injury caused by IRI was markedly reduced as a result of RelB siRNA treatment. Additionally, with RelB siRNA treatment, immunohistochemistry showed a significant attenuation of tumor necrosis factor-alpha expression. Furthermore, survival experiments revealed that more than 90% of control mice died from lethal IRI, whereas 80% of siRNA-pretreated mice survived until the end of the 8-day observation period.. Silencing RelB, using siRNA, can significantly attenuate IRI-induced renal dysfunction and protect mice against lethal kidney ischemia, highlighting the potential for siRNA-based clinical therapy.

Topics: Animals; DNA Primers; Gene Silencing; Kidney; Male; Mice; Mice, Inbred Strains; Peroxidase; Renal Circulation; Reperfusion Injury; Restriction Mapping; Reverse Transcriptase Polymerase Chain Reaction; RNA, Small Interfering; Transcription Factor RelB

Renal ischemia/reperfusion is a common cause of acute renal failure. Glycine is an effective anti-inflammatory, cytoprotective agent and is reported to have a beneficial effect against ischemia/reperfusion injury in various organs. Previous research notes that free radicals and inflammatory leukocytes both play important roles in the pathogenesis of renal ischemia/reperfusion injury. To develop new therapeutic agents against renal ischemia/reperfusion injury, we sought to link an antioxidant moiety (nitronyl nitroxide) to glycine in the hope that the resulting glycine-nitronyl nitroxide conjugate (GNN) would provide a synergetic protection against renal ischemia/reperfusion injury. In this manuscript, we report the synthesis and biological evaluation of the GNN conjugate. The biological activity of the GNN conjugate was evaluated in an in vivo rat model of renal ischemia/reperfusion induced injury and oxidative change. Since the GNN conjugate markedly reduced elevated levels of tissue lipid peroxidation and attenuated renal dysfunction in rats subjected to renal ischemia/reperfusion, it might be possible to develop the GNN conjugate into a potential therapeutic agent against renal ischemia/reperfusion injury.

Topics: Acetylcholine; Animals; Anti-Inflammatory Agents; Blood Urea Nitrogen; Free Radical Scavengers; Glutathione; Glycine; In Vitro Techniques; Kidney; Male; Malondialdehyde; Nitrogen Oxides; Oxidative Stress; PC12 Cells; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Vasodilation

Lung ischemia-reperfusion (IR) injury leads to significant morbidity and mortality which remains a major obstacle after lung transplantation. However, the role of various subset(s) of lung cell populations in the pathogenesis of lung IR injury and the mechanisms of cellular protection remain to be elucidated. In the present study, we investigated the effects of adenosine A2A receptor (A2AAR) activation on resident lung cells after IR injury using an isolated, buffer-perfused murine lung model.. To assess the protective effects of A2AAR activation, three groups of C57BL/6J mice were studied: a sham group (perfused for 2 hr with no ischemia), an IR group (1 hr ischemia + 1 hr reperfusion) and an IR+ATL313 group where ATL313, a specific A2AAR agonist, was included in the reperfusion buffer after ischemia. Lung injury parameters and pulmonary function studies were also performed after IR injury in A2AAR knockout mice, with or without ATL313 pretreatment. Lung function was assessed using a buffer-perfused isolated lung system. Lung injury was measured by assessing lung edema, vascular permeability, cytokine/chemokine activation and myeloperoxidase levels in the bronchoalveolar fluid.. After IR, lungs from C57BL/6J wild-type mice displayed significant dysfunction (increased airway resistance, pulmonary artery pressure and decreased pulmonary compliance) and significant injury (increased vascular permeability and edema). Lung injury and dysfunction after IR were significantly attenuated by ATL313 treatment. Significant induction of TNF-alpha, KC (CXCL1), MIP-2 (CXCL2) and RANTES (CCL5) occurred after IR which was also attenuated by ATL313 treatment. Lungs from A2AAR knockout mice also displayed significant dysfunction, injury and cytokine/chemokine production after IR, but ATL313 had no effect in these mice.. Specific activation of A2AARs provides potent protection against lung IR injury via attenuation of inflammation. This protection occurs in the absence of circulating blood thereby indicating a protective role of A2AAR activation on resident lung cells such as alveolar macrophages. Specific A2AAR activation may be a promising therapeutic target for the prevention or treatment of pulmonary graft dysfunction in transplant patients.

Topics: Adenosine A2 Receptor Agonists; Animals; Blood Platelets; Bronchoalveolar Lavage Fluid; Capillary Permeability; Chemokines; Cytokines; Lung; Lung Diseases; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophil Infiltration; Neutrophils; Peroxidase; Piperidines; Receptor, Adenosine A2A; Reperfusion Injury; Respiratory Function Tests

The intestine is highly susceptible to ischemia/reperfusion (I/R) injury. Splanchnic ischemia is the initial event that releases injurious factors, leading to systemic disorders with high morbidity and mortality. Oxidative stress mediators are believed to contribute to the intestinal I/R injury. Resveratrol, a polyphenol found in grapes, is shown to be a strong antioxidant in various tissues, with a property of an estrogen-receptor agonist. Therefore, we investigated the effects of resveratrol on oxidative injury in the intestine. Female Wistar rats were randomly allocated into four groups (n = 8, each). The sham group was only subjected to surgical procedures, while other animals were subjected to intestinal ischemia (60 min) and subsequent reperfusion (60 min). One group received resveratrol (15 mg/kg, 0.3 ml/day intraperitoneally) for both 5 days before surgery and 15 min before ischemia, while the other was treated intraperitoneally with 0.5% ethyl alcohol as vehicle (0.3 ml/day). In the I/R rat intestines, we detected severe tissue injuries (p < 0.001), the significant increases in the tissue levels of malondialdehyde (MDA), nitric oxide (NO), and myeloperoxidase (MPO) (p < 0.001), and the decrease in superoxide dismutase (SOD) activity (p < 0.001), compared to the sham control. Resveratrol significantly ameliorated the intestinal injury, decreased MDA, NO and MPO levels to the sham control levels, and decreased bacterial translocation in mesentery lymph nodes, liver and spleen (p < 0.001). Resveratrol also restored the SOD activity. These results suggest that resveratrol could protect intestinal tissue against I/R injury with its potent antioxidant properties.

Topics: Animals; Antioxidants; Bacterial Translocation; Female; Free Radical Scavengers; Intestinal Mucosa; Intestines; Malondialdehyde; Nitrates; Nitric Oxide; Nitrites; Peroxidase; Proteins; Rats; Rats, Wistar; Reperfusion Injury; Resveratrol; Stilbenes; Superoxide Dismutase

We investigated the protective effects of magnolol, an active antioxidant and free radical scavenger extracted from Magnolia officinalis, in a hind limb ischemic-reperfusion animal model. Adult male Sprague-Dawley rats were subjected to hind limb ischemic insult for 2 hours and were intravenously treated with magnolol at 0.01 mg/kg (n=8), 0.3 mg/kg (n=8) mg/kg or 1 mg/kg (n=8) mg/kg, or vehicle (n=8). At 24 h post-insult, the levels of nitrite/nitrate (NOX), malondialdehyde (MDA) and myeloperoxidase (MPO), as well as the degree of muscle damage, were assessed. Relative to controls, animals treated with magnolol (0.3 and 1 mg/kg) had attenuated muscular inflammation, edema and damage. Magnolol (0.3-1 mg/kg) also effectively reduced postischemic rises in the MDA, NOx and MPO levels (p<0.05, respectively). Magnolol administrated at 0.01 mg/kg, however, failed to protect against the ischemic-perfusion limb injury. In addition, magnolol (0.01-1 mg/kg) did not affect local muscular blood reperfusion or other physiological parameters, including hematocrit, glucose, arterial blood gases and mean arterial blood pressure. Thus, intravenous administration with magnolol at 0.3-1 mg/kg protects against ischemic limb damage in rats. This cytoprotection may be attributed to its antioxidant, anti-nitrosative and anti-inflammatory actions.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Biphenyl Compounds; Body Temperature; Drug Evaluation, Preclinical; Hindlimb; Lignans; Magnolia; Male; Malondialdehyde; Nitric Oxide; Peroxidase; Phytotherapy; Plant Extracts; Rats; Rats, Sprague-Dawley; Regional Blood Flow; Reperfusion Injury

Recent studies have shown that neutrophils play an important role in the pathogenesis of reperfusion injury. Using an inferior epigastric artery skin flap as a flap ischemia/reperfusion (I/R) injury model, we investigated whether the administration of montelukast sodium, a selective reversible cysteinyl leukotriene 1 (CysLT1) receptor antagonist, decreases neutrophil infiltration and promotes flap survival.. Eighteen rats were used and randomly divided into three groups (n=6 for each group). Group I was the sham group and did not undergo ischemic insult; rather, normal saline (1 mL) was administrated intraperitonealy (i.p.) 30 min before surgery and continued for 6 d. Group II (control) and Group III (montelukast) underwent 12 h of ischemic insult. For Group II, normal saline (1 mL) was injected i.p. 30 min before the surgery and immediately before reperfusion, and this continued for 6 d. In Group III, 1 mL of montelukast (10mg/kg) was injected i.p. and continued for 6 d. Malondialdehyde (MDA) and glutathione (GSH) levels and myeloperoxidase (MPO) enzyme activities were investigated. Histological evaluation was made to investigate the tissue neutrophil count. Survival areas were assessed at 7 d postoperatively.. Group III (montelukast- treated) showed a significantly higher survival rate than Group II (control) (P=0.029) but a lower survival rate than Group I (sham). Histological and biochemical assays corroborated this data.. This study suggests that montelukast CysLT1 receptor antagonist montelukast reversed I/R-induced oxidant responses and improved flap survival by inhibiting neutrophil infiltration and balancing oxidant and antioxidant status.

Topics: Acetates; Animals; Cell Movement; Cyclopropanes; Glutathione; Graft Survival; Injections, Intraperitoneal; Leukotriene Antagonists; Male; Malondialdehyde; Models, Animal; Neutrophils; Peroxidase; Quinolines; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Skin Transplantation; Sulfides; Surgical Flaps; Treatment Outcome

To investigate the possible protective effects of carnosol on liver injury induced by intestinal ischemia reperfusion (I/R).. Rats were divided randomly into three experimental groups: sham, intestinal I/R and carnosol treatment (n = 18 each). The intestinal I/R model was established by clamping the superior mesenteric artery for 1 h. In the carnosol treatment group, surgery was performed as in the intestinal I/R group, with intraperitoneal administration of 3 mg/kg carnosol 1 h before the operation. At 2, 4 and 6 h after reperfusion, rats were killed and blood, intestine and liver tissue samples were obtained. Intestine and liver histology was investigated. Serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and interleukin (IL)-6 were measured. Liver tissue superoxide dismutase (SOD) and myeloperoxidase (MPO) activity were assayed. The liver intercellular adhesion molecule-1 (ICAM-1) and nuclear factor kappaB (NF-kappaB) were determined by immunohistochemical analysis and western blot analysis.. Intestinal I/R induced intestine and liver injury, characterized by histological changes, as well as a significant increase in serum AST and ALT levels. The activity of SOD in the liver tissue decreased after I/R, which was enhanced by carnosol pretreatment. In addition, compared with the control group, carnosol markedly reduced liver tissue MPO activity and serum IL-6 level, which was in parallel with the decreased level of liver ICAM-1 and NF-kappaB expression.. Our results indicate that carnosol pretreatment attenuates liver injury induced by intestinal I/R, attributable to the antioxidant effect and inhibition of the NF-kappaB pathway.

Topics: Abietanes; Alanine Transaminase; Animals; Aspartate Aminotransferases; Chemoprevention; Intercellular Adhesion Molecule-1; Interleukin-6; Intestinal Mucosa; Intestines; Liver; Male; Neutrophils; NF-kappa B; Peroxidase; Random Allocation; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase

Neutrophils are considered crucial effector cells in the pathophysiology of organ ischemia/reperfusion injury (IRI). Although neutrophil elastase (NE) accounts for a substantial portion of the neutrophil activity, the function of NE in liver IRI remains unclear. This study focuses on the role of NE in the mechanism of liver IRI. Partial warm ischemia was produced in the left and middle hepatic lobes of C57BL/6 mice for 90 minutes, and this was followed by 6 to 24 hours of reperfusion. Mice were treated with neutrophil elastase inhibitor (NEI; 2 mg/kg per os) at 60 minutes prior to the ischemia insult. NEI treatment significantly reduced serum alanine aminotransferase levels in comparison with controls. Histological examination of liver sections revealed that unlike in controls, NEI treatment ameliorated hepatocellular damage and decreased local neutrophil infiltration, as assessed by myeloperoxidase assay, naphthol AS-D chloroacetate esterase stains, and immunohistochemistry (anti-Ly-6G). The expression of pro-inflammatory cytokines (tumor necrosis factor alpha and interleukin 6) and chemokines [chemokine (C-X-C motif) ligand 1 (CXCL-1), CXCL-2, and CXCL-10] was significantly reduced in the NEI treatment group, along with diminished apoptosis, according to terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining and caspase-3 activity. In addition, toll-like receptor 4 (TLR4) expression was diminished in NEI-pretreated livers, and this implies a putative role of NE in the TLR4 signal transduction pathway. Thus, targeting NE represents a useful approach for preventing liver IRI and hence expanding the organ donor pool and improving the overall success of liver transplantation. Liver Transpl 15:939-947, 2009. (c) 2009 AASLD.

Topics: Animals; Apoptosis; Carboxylic Ester Hydrolases; Enzyme Inhibitors; Humans; Immunohistochemistry; Leukocyte Elastase; Liver; Liver Transplantation; Male; Mice; Mice, Inbred C57BL; Naphthols; Peroxidase; Reperfusion Injury; Treatment Outcome

Various leukocyte populations, including neutrophils and CD4 T cells, have been implicated as mediators of acute renal ischemic injury. The influence of ischemic temperature on molecular and cellular mechanisms mediating this injury was tested in a mouse model. Wild-type C57BL/6, B6.CD4(-/-), B6.CD8(-/-), and B6.RAG-1(-/-) mice subjected to bilateral renal pedicle occlusion for 30 min at a higher (37 degrees C) but not a lower (32 degrees C) ischemic maintenance temperature had clear evidence of renal dysfunction and histopathology. Ischemia imposed at the higher temperature also increased CXCL1/KC and CXCL2/MIP-2 levels and neutrophils, but not T cells or macrophages, infiltrating into the ischemic kidneys. Depletion of neutrophils but not T cells attenuated the acute ischemic injury. These results indicate the influence of ischemic temperature and time on the production of neutrophil chemoattractants and subsequent neutrophil infiltration to mediate acute ischemic injury but fail to identify a role for adaptive immune components in this injury.

Topics: Animals; Apoptosis; Body Temperature; Capillary Permeability; CD4 Antigens; CD4-Positive T-Lymphocytes; CD8 Antigens; CD8-Positive T-Lymphocytes; Cell Count; Chemokine CCL2; Chemokine CXCL1; Chemokine CXCL2; Chemotactic Factors; Creatinine; Cytokines; Gene Expression; Homeodomain Proteins; Kidney; Lymphocyte Depletion; Macrophages; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophils; Peroxidase; Reperfusion Injury

Endothelial cells express the ectoenzyme ectonucleoside adenosine triphosphate diphosphohydrolase, an apyrase that inhibits vascular inflammation by catalyzing the hydrolysis of adenosine triphosphate and adenosine diphosphate. However, ectonucleoside adenosine triphosphate diphosphohydrolase expression is rapidly lost following oxidative stress, leading to the potential for adenosine triphosphate and related purigenic nucleotides to exacerbate acute solid organ inflammation and injury. We asked if administration of a soluble recombinant apyrase APT102 attenuates lung graft injury in a cold ischemia reperfusion model of rat syngeneic orthotopic lung transplantation.. Male Fisher 344 donor lungs were cold preserved in a low-potassium dextrose solution in the presence or absence of APT102 for 18 hours prior to transplantation into syngeneic male Fisher 344 recipients. Seven minutes after reperfusion, lung transplant recipients received either a bolus of APT102 or vehicle (saline solution). Four hours after reperfusion, APT102- and saline solution-treated groups were evaluated for lung graft function and inflammation.. APT102 significantly reduced lung graft extracellular pools of adenosine triphosphate and adenosine diphosphate, improved oxygenation, and protected against pulmonary edema. Apyrase treatment was associated with attenuated neutrophil graft sequestration and less evidence of tissue inflammation as assessed by myeloperoxidase activity, expression of proinflammatory mediators, and numbers of apoptotic endothelial cells.. Administration of a soluble recombinant apyrase promotes lung function and limits the tissue damage induced by prolonged cold storage, indicating that extracellular purigenic nucleotides play a key role in promoting ischemia-reperfusion injury following lung transplantation.

Topics: Adenosine Diphosphate; Adenosine Triphosphate; Animals; Apoptosis; Apyrase; Bronchopulmonary Sequestration; Chemokines; Cytokines; Endothelium, Vascular; Leukocyte Count; Lung Transplantation; Male; Neutrophils; Peroxidase; Pulmonary Edema; Rats; Rats, Inbred F344; Recombinant Proteins; Reperfusion Injury

Elevated cytokine levels have been reported after ischemia/reperfusion injury and might cause a systemic inflammatory response syndrome (SIRS) after primary percutaneous coronary intervention (PPCI). High myeloperoxidase (MPO) levels are reported to be a risk factor for early cardiac events in patients with acute coronary syndrome. Its role as a predictor of SIRS in patients with ST-segment elevation myocardial infarction treated with PPCI is unclear. Therefore, the aim of the present study was to investigate the role of MPO as a predictor of SIRS in patients with ST-segment elevation myocardial infarction treated with PPCI. A total of 250 patients with ST-segment elevation myocardial infarction treated with PPCI were admitted to our coronary care unit. The serum MPO levels were measured at admission using a commercially available enzyme-linked immunosorbent assay. Of the 250 patients, 47 developed SIRS within 48 hours after their admission to the coronary care unit; 10 of these patients were excluded from analysis because of the suspicion of sepsis. The remaining 203 patients had no SIRS during their coronary care unit stay. Compared to patients without SIRS, those with SIRS had greater serum MPO values (81.35 +/- 18.07 vs 67.03 +/- 16.98 ng/ml, p <0.0001) after PPCI. After controlling for different baseline clinical, laboratory, and angiographic variables, the baseline serum MPO levels were an independent predictor of SIRS (odds ratio 4.2, 95% confidence interval 1.9 to 8.4, p <0.001). In conclusion, our results have demonstrated that MPO is an independent predictor of SIRS after PPCI, suggesting a new clue for the interpretation of this phenomenon.

Topics: Aged; Angioplasty, Balloon, Coronary; Enzyme-Linked Immunosorbent Assay; Female; Humans; Male; Middle Aged; Myocardial Infarction; Peroxidase; Predictive Value of Tests; Prognosis; Reperfusion Injury; Systemic Inflammatory Response Syndrome

The aim of this study was to determine whether resveratrol could prevent intestinal tissue injury induced by ischemia-reperfusion (I/R).. Intestinal I/R was induced in rats' intestines by 60-min occlusion of the superior mesenteric artery, followed by a 60-min reperfusion. Thirty rats were divided into three groups as follows: sham (group 1), control (group 2), and the treatment groups (group 3). The rats in the treatment group received resveratrol both before ischemia and before reperfusion. In all groups, serum aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase levels were determined. Total antioxidant capacity (TAC), catalase, total oxidative status (TOS), oxidative stress index (OSI), and myeloperoxidase (MPO) in the intestinal tissue were measured. Intestinal tissue histopathology was also evaluated by light microscopy.. The levels of liver enzymes in group 3 were significantly lower than those in group 2 (P < 0.05). TAC in the intestinal tissue was significantly higher in group 3 than in group 2 (P < 0.05). TOS, OSI, and MPO in the intestinal tissue were significantly lower in group 3 than in group 2 (P < 0.05 for all). Histological tissue damage was milder in the resveratrol treatment group than in the control group.. The results of this study indicated that resveratrol treatment limits the oxidative injury of the small intestine induced by I/R in rats. However, more precise investigations are required to evaluate the antioxidative effect of resveratrol on small intestine tissue damage in clinical and experimental models.

Topics: Alanine Transaminase; Animals; Antioxidants; Aspartate Aminotransferases; Biomarkers; Catalase; Disease Models, Animal; Intestine, Small; L-Lactate Dehydrogenase; Liver; Male; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Resveratrol; Stilbenes

Hyperglycemia amplifies the inflammatory state after ischemia/reperfusion (I/R), and activated neutrophils have been implicated in the development of I/R-induced renal injuries. D-ribose is a naturally occurring monosaccharide found in all living cells. In this study, we examined whether D-ribose attenuates I/R-induced renal injury by reducing neutrophil activation in rats with transient hyperglycemia. Male Wistar rats were divided into sham (n = 24), control (n = 64), and D-ribose (n = 32) groups. Rats received intraperitoneal injection of glucose (3 g/kg) 30 min before induction of ischemia to induce transient hyperglycemia. Anesthetized rats underwent right nephrectomy and subsequent occlusion of the left renal artery and vein for 45 min. D-ribose (400 mg/kg) was intravenously administered 30 min before induction of ischemia. D-ribose significantly reduced the degree of the I/R-induced increases in renal concentrations of cytokine-induced neutrophil chemoattractant-1 (a chemotactic factor for the activation of neutrophils and chemotaxis to the site of injury) and myeloperoxidase (an indicator of neutrophils infiltration). D-ribose also reduced the I/R-induced increases in serum levels of blood urea nitrogen and creatinine, and improved histological changes, including acute tubular necrosis in the corticomedullary junction fields. These results indicate that D-ribose reduces the I/R-induced acute renal injury in rats with transient hyperglycemia, probably by reducing neutrophil activation. D-ribose might thus be useful for surgical procedures, such as renal transplant surgery, under hyperglycemia.

Topics: Animals; Chemokine CXCL1; Hyperglycemia; Kidney Diseases; Kidney Function Tests; Male; Peroxidase; Protective Agents; Rats; Rats, Wistar; Reperfusion Injury; Ribose

Several recent studies have shown that ischemic postconditioning (IPostC) protects hears from ischemic reperfusion insults in various animal models. However, the mechanism of IPostC remains unclear. In the present study, we investigated the hypothesis that PostC protected kidneys against ischemic reperfusion injury by modifying renal oxidative stress and lipid peroxidation. Rats underwent 45 minutes of renal pedicle ligature followed by reperfusion for 1, 3, 6, 12, or 24 hours. IPostC was performed using 6, 10 second cycles of reperfusion and 10 seconds of renal pedicle occlusion at the end of the ischemia. Our data showed that IPostC attenuated renal dysfunction, significantly increasing the activity of antioxidases, including superoxide dismutase (SOD), catalase (CAT), and glutathione perokidase (GSH-Px) in renal homogenates, and concentrations of GSH and SOD expression. The level of malondialdehyde (MDA) and the activity of myeloperoxidase (MPO) were significantly decreased in IPostC rats. These results indicated that the protective effects of IPosC may be related to modification of renal oxidative stress and lipid peroxidation caused by ischemic reperfusion injury in rats.

Topics: Animals; Blood Urea Nitrogen; Catalase; Disease Models, Animal; Gene Expression Regulation, Enzymologic; Glutathione; Kidney; Lipid Peroxidation; Oxidative Stress; Peroxidase; Postoperative Complications; Rats; Reperfusion Injury; Superoxide Dismutase

Curcumin is an anti-oxidant molecule known to be a potent inhibitor of nuclear factor-kappaB (NF-kappaB). It has been shown to attenuate ischemia/reperfusion (I/R) injury in several organ systems. In this study, we sought to investigate the effects of curcumin on the prevention of superior mesenteric artery I/R injury in rats.. Wistar albino rats were randomly allocated to 3 groups: group I, sham operated (n = 10); group II, I/R injury only (n = 10); group III, curcumin-treated I/R cohort (n = 10). Group I animals underwent laparotomy without I/R injury. After group II animals underwent laparotomy, 60 minutes of superior mesenteric artery ligation were followed by 3 hours of reperfusion. In the curcumin group, 15 days before I/R, curcumin (40 mg/kg) was administered by gastric gavage. All animals were sacrificed at the end of reperfusion. Intestinal tissue samples were obtained to investigate intestinal mucosal injury; in addition we estimated levels of myeloperoxidase (MPO) activity, malondialdehyde (MDA), nitric oxide (NO), glutathione (GSH), interleukin (IL)-6, and tumor necrosis factor (TNF)-alpha.. There were statistically significant decreases in GSH levels, along with an increase in intestinal mucosal injury scores, MPO activity, MDA levels, NO, IL-6, and TNF-alpha in group I when compared with groups II and III (P = .01). Curcumin treatment in group III produced a significant increase in GSH levels, as well as a decrease in intestinal mucosal injury scores, MPO activity, MDA, and NO levels when compared with group II (P < .05).. This study showed that curcumin treatment significantly attenuated reperfusion injury in a superior mesenteric artery I/R model in rats.

Topics: Animals; Curcumin; Disease Models, Animal; Gastric Lavage; Glutathione; Interleukin-6; Intestinal Mucosa; Male; Malondialdehyde; Nitric Oxide; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Splanchnic Circulation; Tumor Necrosis Factor-alpha

NADPH oxidase is an enzyme that converts molecular oxygen into reactive oxygen species, which cause severe damage in several organs. Cyclooxygenase (COX)-2 is an inducible enzyme that is important in gastric mucosal defense and repair processes. It is unclear whether NADPH oxidase is related to COX expression in the gastric mucosa, so we investigated the correlation. Under urethane anesthesia, a male Sprague Dawley rat stomach was mounted in an ex-vivo chamber, and ischemia/reperfusion (I/R) was performed through a cannula in the femoral vein. I/R significantly increased NADPH oxidase activity, H(2)O(2) production, and myeloperoxidase (MPO) activity. In contrast, ischemia alone clearly enhanced both NADPH oxidase activity and H(2)O(2) production but not MPO activity. Pretreatment with the NADPH oxidase inhibitor diphenylene iodonium (DPI) suppressed I/R-induced mucosal damage. On the other hand, the selective COX-2 inhibitor rofecoxib exhibited a tendency to enhance the severity of gastric damage induced by I/R, although the selective COX-1 inhibitor SC-560 and the nonselective COX inhibitor indomethacin had no effect. I/R also increased the expression of COX-2, and this increase was suppressed by pretreatment with DPI. These findings suggest that the increase in NADPH oxidase activity is involved in the occurrence of gastric mucosal damage induced by I/R and that this enzyme activity may be causally related to the upregulation of COX-2 during I/R.

Topics: Animals; Cyclooxygenase 1; Cyclooxygenase 2; Cyclooxygenase Inhibitors; Enzyme Inhibitors; Gastric Mucosa; Hydrogen Peroxide; Indomethacin; Ischemia; Lactones; Male; NADPH Oxidases; Onium Compounds; Peroxidase; Pyrazoles; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sulfones; Up-Regulation

To investigate the effects of a novel Leukotriene B(4) receptor antagonist and/or tacrolimus on ischemia-reperfusion in a rat liver model.. Male Lewis rats were pretreated with ONO-4057 (100 mg/kg) and/or tacrolimus (1 mg/kg) orally, and divided into four experimental groups; group 1 (control), group 2 (ONO-4057), group 3 (tacrolimus), group 4 (ONO-4057 + tacrolimus).. There was a tendency for long survival in the groups treated with tacrolimus alone and ONO-4057 plus tacrolimus. Post-reperfusion serum aspartate aminotransferase levels decreased more significantly in ONO-4057 plus tacrolimus group (P < 0.01), than in the tacrolimus alone group (P < 0.05), compared to controls.. This study demonstrated that pretreatment with ONO-4057 in combination with tacrolimus produced additive effects in a rat model of liver ischemia-reperfusion injury.

Topics: Animals; Immunosuppressive Agents; Liver; Male; Peroxidase; Phenylpropionates; Rats; Rats, Inbred Lew; Reperfusion Injury; Tacrolimus

We tested our hypothesis that postischemic conditioning (PostC) is effective in salvage of ischemic skeletal muscle from reperfusion injury and the mechanism involves inhibition of opening of the mitochondrial permeability transition pore (mPTP). In bilateral 8x13 cm pig latissimus dorsi muscle flaps subjected to 4 h ischemia, muscle infarction increased from 22+/-4 to 41+/-1% between 2 and 24 h reperfusion and remained unchanged at 48 (38+/-6%) and 72 (40+/-1%) h reperfusion (P<0.05; n=4 pigs). PostC induced by four cycles of 30-s reperfusion/reocclusion at the onset of reperfusion after 4 h ischemia reduced muscle infarction from 44+/-2 to 22+/-2% at 48 h reperfusion. This infarct protective effect of PostC was mimicked by intravenous injection of the mPTP opening inhibitor cyclosporin A or NIM-811 (10 mg/kg) at 5 min before the end of 4 h ischemia and was abolished by intravenous injection of the mPTP opener atractyloside (10 mg/kg) at 5 min before PostC (P<0.05; n=4-5 pigs). PostC or intravenous cyclosporin A injection at 5 min before reperfusion caused a decrease in muscle myeloperoxidase activity and mitochondrial free Ca2+ concentration and an increase in muscle ATP content after 4 h ischemia and 2 h reperfusion compared with the time-matched controls. These effects of PostC were abolished by intravenous injection of atractyloside at 5 min before PostC (P<0.05; n=6 pigs). These observations support our hypothesis that PostC is effective in salvage of ischemic skeletal muscle from reperfusion injury and the mechanism involves inhibition of opening of the mPTP.

Topics: Adenosine Triphosphate; Animals; Atractyloside; Calcium; Cyclosporine; Disease Models, Animal; Infarction; Injections, Intravenous; Mitochondria, Muscle; Mitochondrial Membrane Transport Proteins; Mitochondrial Permeability Transition Pore; Muscle, Skeletal; Peroxidase; Reperfusion Injury; Swine; Time Factors

Tempol is a stable piperidine nitroxide of low molecular weight that permeates biological membranes and scavenges superoxide anions in vitro. In a variety of animal models, deleterious effects of reperfusion injury on both local and remote organs have been demonstrated. In this study, we aimed to investigate the effects of a membrane-permeable radical scavenger, Tempol, on local and remote organ injuries caused by intestinal ischemia/reperfusion (I/R) in rats.. Male Wistar-albino rats were randomized into three groups: (I) Sham-operated control group, laparotomy without I/R injury (n = 12); (II) Intestinal I/R group, 60 min of ischemia by superior mesenteric artery occlusion followed by 2-h of reperfusion (n = 12); and (III) I/R + Tempol-treated group, identical to I/R group except for Tempol administration, 30 mg/kg bolus injection 5 min before reperfusion, followed by an infusion of 30 mg/kg/h intravenously (n = 12). Histopathologically, intestinal mucosal lesions were assessed by Chiu's classification, and pulmonary parenchymal damage was appraised by pulmonary neutrophil infiltration and acute lung injury scaling. Biochemically, myeloperoxidase activity, malondialdehyde, glutathione, and nitrite/nitrate (NO(x)) levels were determined in both intestinal mucosa and lung parenchyma. Evans blue dye concentration and organ wet/dry weight ratios were used as a marker of organ edema. Animal survival was observed up to 1 week.. Intestinal mucosal lesions and pulmonary parenchymal damage were significantly attenuated with Tempol treatment, histopathologically (P < 0.05). Tempol administration significantly reduced myeloperoxidase activity and malondialdehyde levels, and also significantly increased glutathione and NO(x) levels of both intestinal and lung tissues, biochemically (P < 0.05). Evans blue dye extravasation and wet/dry weight ratios of organs were significantly reduced with Tempol injection (P < 0.05). The survival rates of rats in Tempol-treated group were significantly higher than that of I/R-treated group (P < 0.05).. The present study suggests that Tempol administration significantly reduces both local and remote organ injuries caused by intestinal I/R before and throughout the reperfusion period. Further clinical studies are needed to clarify whether Tempol may be a useful therapeutic agent to use in particular operations where the reperfusion injury occurs.

Topics: Animals; Capillary Permeability; Cyclic N-Oxides; Edema; Free Radical Scavengers; Glutathione; Intestinal Mucosa; Lung; Male; Malondialdehyde; Mesenteric Artery, Superior; Mesenteric Vascular Occlusion; Neutrophils; Nitrates; Nitrites; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Respiratory Distress Syndrome; Spin Labels

Oxidative stress may have a role in liver damage after acute renal injury due to various reasons such as ischemia reperfusion (IR). Diabetes mellitus (DM) is an important disease for kidneys and may cause nephropathy as a long term complication. The aim of this study was to investigate protective effect of melatonin, a potent antioxidant, against distant organ injury on liver induced by renal IR in rats with or without DM. The rats were divided into six groups: control (n=7), DM (n=5), IR (n=7), DM+IR (n=7), melatonin+IR (Mel+IR) (melatonin, 4 mg/ kg during 15 days) (n=7), and Mel+DM+IR groups (n=7). Diabetes developed 3 days after single i.p. dose of 45 mg/kg streptozotocin. After 15 day, the left renal artery was occluded for 30 min followed 24 h of reperfusion in IR performed groups. DM did not alter oxidative parameters alone in liver tissue. The levels of malondialdehyde, protein carbonyl and nitric oxide with activities of xanthine oxidase and myeloperoxidase were increased in liver tissues of diabetic and non-diabetic IR groups. Nitric oxide level in DM was higher than control. The activities of catalase and superoxide dismutase were increased in IR groups in comparison with control and DM. ALT and AST levels were higher in IR and DM+IR groups than control and DM. Melatonin treatment reversed all these oxidant and antioxidant parameters to control values as well as serum liver enzymes. We concluded that renal IR may affect distant organs such as liver and oxidative stress may play role on this injury, but DM has not an effect on kidney induced distant organ injury via oxidant stress. Also, it was concluded that melatonin treatment may prevent liver oxidant stress induced by distant injury of kidney IR.

Topics: Alanine Transaminase; Animals; Antioxidants; Aspartate Aminotransferases; Catalase; Diabetes Mellitus, Experimental; Kidney; Liver; Liver Diseases; Male; Malondialdehyde; Melatonin; Nitric Oxide; Oxidative Stress; Peroxidase; Protein Carbonylation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase; Xanthine Oxidase

Classic studies of limb ischemia-reperfusion injury have been performed using young healthy mice. However, patients with peripheral vascular disease are older and often exhibit metabolic derangements that may delay healing after revascularization. Mice with genetic deletion of apolipoprotein E (ApoE(-/-)) have been used as a model in various experimental scenarios of hypercholesterolemia. These experiments evaluated the inflammatory response and changes in skeletal muscle morphology during the acute and chronic phases of limb ischemia-reperfusion injury in aged ApoE(-/-) mice.. Age-matched ApoE(-/-) and wild-type (Wt) mice underwent 1.5 hours of unilateral hind limb ischemia, followed by 1, 7, or 14 days of reperfusion (DR). Histologic analysis of skeletal muscle fiber injury was assessed at 1DR. Morphologic evidence of muscular fiber maturation was assessed at 14DR. Levels of MyoD and myogenin, markers of skeletal muscle differentiation, were assessed at 7 and 14DR using Western blots. Markers of inflammation, including myeloperoxidase, macrophage inflammatory protein-2 (MIP-2), monocyte chemotactic protein-1 (MCP-1), and osteopontin, were assayed using enzyme-linked immunosorbent assay and chemokine (C-C motif) receptor 2 (CCR2) using Western blots at 1, 7, and 14DR. After 1DR, tissue adenosine 5'-triphosphate (ATP) levels were measured to assess metabolic activity. Unpaired t test and Mann-Whitney test were used for comparisons.. Histologic evaluation of skeletal muscle after 1DR showed no difference in the degree of injury between Wt and ApoE(-/-) mice. However, at 14DR, ApoE(-/-) mice had higher percentage of immature muscle fibers than Wt mice. Myogenin level was lower in the ApoE(-/-) mice at 7DR. Injured skeletal muscle of ApoE(-/-) mice had lower levels of myeloperoxidase than Wt mice at 7 DR and higher levels of MCP-1 at 14DR. There was no difference in the levels of tissue ATP, MIP-2, osteopontin, or CCR2 at all experimental intervals.. Although there was no difference between the injured muscle of Wt and ApoE(-/-) mice during the acute phase of reperfusion, ApoE(-/-) mice showed delay in skeletal muscle healing during the chronic phase of reperfusion. This lag in muscle regeneration was associated with lower levels of myogenin at 7DR and an increased level of MCP-1 at 14DR in the ApoE(-/-) mice. The delay in skeletal muscle healing in the ApoE(-/-) mice may have broader implications for poor tissue healing and functional recovery in elderly patients who have vascular risk factors such as hypercholesterolemia.

Topics: Adenosine Triphosphate; Animals; Apolipoproteins E; Blotting, Western; Chemokine CCL2; Chemokine CXCL2; Cholesterol; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Female; Hindlimb; Hypercholesterolemia; Mice; Mice, Inbred C57BL; Mice, Knockout; Muscle, Skeletal; MyoD Protein; Myogenin; Osteopontin; Peroxidase; Receptors, CCR2; Reperfusion Injury; Time Factors; Wound Healing

To evaluate the effects of different fluid resuscitation strategies on superoxide dismutase (SOD), malondialdehyde (MDA) and myeloperoxidase (MPO) activities in the lung tissue in pregnant rabbits with uncontrolled hemorrhagic shock.. Thirty pregnant New Zealand rabbits were randomized into 5 equal groups, namely the sham shock.(SS) group, shock group without interventions (SH group), and hemorrhagic shock groups with conventional normal saline (NS) resuscitation, NS hypotensive resuscitation, and hypertonic hyperosmotic hypotensive resuscitation (NS, NH, HHH groups, respectively) 30 min after the shock. At the end of the experiment, the rabbits were sacrificed, and the lungs were taken for detection of MDA, MPO and SOD levels.. Ischemia-reperfusion injury of the lungs in uncontrolled hemorrhagic shock resulted in decreased SOD and increased MDA and MPO contents. The MDA and MPO contents in HHH group were significantly lower than those in NH group, and both the groups, MDA and MPO contents were significantly lower than those of NS group (P<0.05). SOD activity was significantly higher in HHH group than in NH group (P<0.05).. In pregnant rabbits with uncontrolled hemorrhagic shock, hypotensive resuscitation more effectively ameliorates ischemia-reperfusion injuries in the lungs than aggressive fluid resuscitation, and hyperosmotic crystalloid and hyperonoctic colloid resuscitation provide significant protective effects against such injuries.

Topics: Animals; Female; Fluid Therapy; Hypertonic Solutions; Hypotonic Solutions; Lung; Peroxidase; Pregnancy; Pregnancy Complications; Rabbits; Random Allocation; Reperfusion Injury; Resuscitation; Shock, Hemorrhagic; Superoxide Dismutase

We examined whether nuclear factor-kappa B (NF-kappaB) activation was involved in the ischemia-reperfusion (I/R) injury in a rat skin flap model and whether administration of pyrrolidine dithiocarbamate (PDTC), a NF-kappaB inhibitor, could improve flap viability. Eighty-four Sprague-Dawley rats were divided into control group (n = 28), I/R group (n = 28), and PDTC-treated group (n = 28). An abdominal skin flap (4 x 5 cm) was elevated and subjected to 10 hours of ischemia in both the I/R group and the PDTC-treated group. A bolus of PDTC (300 mg/kg) was infused 5 minutes before reperfusion, followed by a second dose during the first 30 minutes of reperfusion in the PDTC-treated group. Flap tissues were assessed by electrophoretic mobility shift assay at 1, 2, 3, and 6 hours of reperfusion, and myeloperoxidase activity and neutrophil infiltration were assessed at 12 hours of reperfusion. The viability of flaps was assessed 7 days postoperatively. NF-kappaB was activated after reperfusion in the I/R group and displayed peak activity at 1 and 3 hours of reperfusion. In the PDTC-treated group, NF-kappaB activity was significantly reduced at 1, 2, and 6 hours of reperfusion. Myeloperoxidase activity was significantly decreased, and little neutrophil infiltration could be observed. In the PDTC-treated group, the survival of flaps was 86.88 +/- 13.63%, which was significantly greater than the I/R group, in which only 19.20 +/- 7.52% of the flap survived. NF-kappaB is activated during reperfusion in a rat skin flap I/R model. Administration of PDTC can significantly improve flap survival by regulating the early activation of NF-kappaB and suppressing neutrophil infiltration within the flap.

Topics: Analysis of Variance; Animals; Electrophoretic Mobility Shift Assay; Epigastric Arteries; Graft Survival; Male; NF-kappa B; Peroxidase; Pyrrolidines; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Surgical Flaps; Thiocarbamates

Curcumin (diferuloylmethane), an active ingredient of turmeric, obtained from the powdered rhizomes of Curcuma longa Linn., has been traditionally recognized for treatment of several diseases. To evaluate the potential clinical use of curcumin, we determined the dose dependence of its effects in the therapeutic window and of the neuroprotective efficacy in a cerebral thromboembolic model of the rat. Rats were subjected to occlusion of the middle cerebral artery (MCAo) by a thrombus and treated with different doses of curcumin or the vehicle at 4h after ischemia. The animals were assessed after 24h for motor performance and neurological deficit. The rats were sacrificed immediately afterwards for evaluation of infarct, edema volume, estimation of nitrate and nitrite levels, neutrophil infiltration and levels of GSH and glutathione peroxidase (GSH-Px) in brain tissue. Curcumin reduced in a dose-dependent manner the ischemia-induced cerebral infarct and edema volume and attenuated neurological deficits observed after 24h. Curcumin reduced post-ischemic brain neutrophil infiltration, nitrate and nitrite levels and ameliorated the loss of GSH-Px and tends to increase the GSH levels but not significantly in the brain tissue. Neuronal levels of reactive oxygen species, peroxynitrite, and nitric oxide were lowered and in brain cryosections inducible nitric oxide synthase expression were significantly inhibited after treatment with curcumin. The present study is the first evidence of effectiveness of curcumin when given 4h post-ischemia in the rat thromboembolic stroke models, as it reduces infarct volume, ameliorates the sensory motor function and significantly attenuated the nitrosative stress.

Topics: Animals; Behavior, Animal; Brain Edema; Brain Ischemia; Cerebrovascular Circulation; Curcumin; Disease Models, Animal; Dose-Response Relationship, Drug; Glutathione Peroxidase; Immunohistochemistry; Infarction, Middle Cerebral Artery; Male; Motor Activity; Neuroprotective Agents; Nitrates; Nitric Oxide; Nitrites; Peroxidase; Peroxynitrous Acid; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Treatment Outcome

Many studies have indicated leukocytes are a major contributor to brain injuries caused by intracerebral hemorrhage (ICH). Leukocyte-expressed CD18 is important for neutrophil-endothelial interactions in the vasculature, and CD18 deficiency protects against ischemia-reperfusion injury. We investigated whether CD18 deficiency provides protection against ICH-induced brain injury. Male wild-type (WT) CD18(+/+) mice and CD18(-/-) -knockout mice were used in this study. ICH was induced by a collagenase injection. Mortality, neurological function, brain edema, and myeloperoxidase (MPO) activity as well as tissue expression of nitrotyrosine and MPO were evaluated 24 hr after ICH. We discovered significantly reduced brain edema and diminished mortality with a concomitant decrease in MPO and nitrotyrosine immunoreactivity in brains of CD18-knockout mice.

Topics: Animals; Brain Edema; CD18 Antigens; Cerebral Hemorrhage; Immunohistochemistry; Male; Mice; Mice, Knockout; Peroxidase; Reperfusion Injury; Tyrosine

Although dapsone (4,4'-diaminodiphenylsulfone) has been described as a neuroprotective agent in occlusive focal ischemia in rats, its mechanism of action is still unknown. To explore this mechanism, oxidative, inflammatory and apoptotic processes were evaluated in the striatum of adult rats using a model of ischemia-reperfusion (I/R), either with or without dapsone treatment. Male Wistar rats were submitted to transient middle cerebral artery occlusion for 2 hr, followed by reperfusion. Rats were dosed either with dapsone (12.5 mg/kg i.p.) or vehicle 30 min before or 30 min after the ischemia onset. Lipid peroxidation (LP) and nitrotyrosine contents were measured 22 hr after reperfusion, and myeloperoxidase activity was evaluated 46 hr after I/R. Different markers for apoptosis and necrosis were also evaluated both at 24 and 72 hr after I/R experimental procedure. LP increased by 37% in ischemic animals vs controls, and this effect was reversed by dapsone treatments. A similar effect was observed regarding nitrotyrosine striatal contents. Myeloperoxidase activity, a marker of inflammatory response, increased 3.7-fold in ischemic animals vs. control rats, and dapsone treatment antagonized that effect. Although apoptosis was increased by the effect of ischemia at both evaluation times, dapsone antagonized that effect only at 72 hr after surgery. Dapsone antagonized all of the I/R end points measured, showing a remarkable ability to decrease markers of damage through antioxidant, antiinflammatory, and anti-apoptotic effects.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Apoptosis; Brain Ischemia; Caspase 3; Caspase 9; Chromatography, High Pressure Liquid; Dapsone; Immunoblotting; In Situ Nick-End Labeling; Lipid Peroxidation; Male; Neuroprotective Agents; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Tyrosine

Activated neutrophils have been implicated in the development of ischemia/reperfusion (I/R)-induced renal failure. Cytokine-induced neutrophil chemoattractant-1 (CINC-1), a major factor in acute inflammation, is responsible for the activation of neutrophils and for neutrophil chemotaxis to sites of injury. Atrial natriuretic peptide (ANP), a hormone synthesized by the cardiac atria, was shown to possess anti-inflammatory potential due to its potency to inhibit the production of inflammatory mediators. We examined whether the human form of ANP attenuates I/R-induced renal injury by reducing neutrophil activation in a rat model. Male Wistar rats weighing 200-240 g were observed for 24 h after reperfusion following 45-min renal ischemia. Rats were intravenously administered alpha-human ANP (alpha-hANP, 0.2 microg/kg/min) beginning immediately after ischemia and continuing for 2 h after reperfusion. CINC-1 and myeloperoxidase (MPO) concentrations were measured to assess activation of the infiltrating neutrophil. Blood urea nitrogen and serum creatinine and urinary N-acetyl beta-d-glucosaminidase (NAG) were measured as indicators of glomerular function and as a specific indicator of proximal tubular function, respectively. alpha-hANP significantly inhibited I/R-induced increases in renal CINC-1 and MPO concentrations. alpha-hANP also reduced I/R-induced increases in the concentrations of blood urea nitrogen and serum creatinine, and improved histopathologic changes, including acute tubular necrosis. These findings indicate that alpha-hANP attenuates I/R-induced acute renal injury, at least in part by reducing neutrophil activation, and may be useful in surgeries, associated with renal ischemia, as well as in renal transplantation.

Topics: Animals; Atrial Natriuretic Factor; Chemokine CXCL1; Creatinine; Hexosaminidases; Inflammation; Kidney; Male; Models, Biological; Neutrophil Activation; Neutrophils; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Although short-term findings after lung reperfusion have been extensively reported, in vivo animal studies have not described outcome beyond the immediate time period. Therefore, the authors evaluated lung injury 27 h after reperfusion. They also investigated whether attenuation of lung injury with the A3 adenosine receptor agonist MRS3558 was sustained beyond the immediate time period.. In intact-chest, spontaneously breathing cats in which the left lower lung lobe was isolated and subjected to 2 h of ischemia and 3 h of reperfusion, MRS3558 was administered before reperfusion. Animals were killed 3 or 27 h after reperfusion.. When compared with 3 h of reperfusion, at 27 h the left lower lobe showed reduced apoptosis and no change in inflammation, but increased edema. Increased edema of the nonischemic right lung and hypoxemia were observed at 27 h after left lower lobe reperfusion. Increases in phosphorylated p38 levels were found at 3 h of reperfusion compared with control lung, with further increases at 27 h. The attenuation of injury observed with MRS3558 treatment at 3 h of reperfusion was sustained at 27 h.. Lung edema may worsen hours after the immediate postreperfusion period, even though lung apoptosis and inflammation are reduced or show no change, respectively. This was associated with further increases in phosphorylated p38 levels. The nonischemic lung may also be affected, suggesting a systemic response to reperfusion. In addition, early attenuation of injury is beneficial beyond the immediate period after reperfusion. Treatment aimed at inhibiting p38 activation, such as A3 receptor activation, should be further studied to explore its potential long-term beneficial effect.

Topics: Adenosine A3 Receptor Agonists; Animals; Apoptosis; Blood Gas Analysis; Cats; Lung Diseases; Mitogen-Activated Protein Kinases; Peroxidase; Reperfusion Injury; Time Factors; Tumor Necrosis Factors

Reperfusion injury by the abrupt restoration of circulation after the prolonged ischemia has been remained unsolved problem in the reconstructive microsurgery. We tested the hypothesis that a procedure of intermittent interruption of reperfusion, i.e., postconditioning (post-con) attenuates ischemia/reperfusion (I/R) injury of rat epigastric skin flap. A complete 4 hours of ischemia was generated by occlusion of the pedicle of dissected flap. The post-con procedure was started at the end of ischemia. A cycle of 15 seconds of full reperfusion, followed by 15 seconds of complete reocclusion was repeated six times (3 min of total intervention) prior to the unlimited reperfusion. Flap necrosis area of post-con group was compared with sham (no ischemic exposure) and control (4 hours of ischemia followed by full reperfusion without intervention) groups at postreperfusion day 5. Histology and MPO activities of flaps were evaluated. The post-con group showed significantly reduced flap necrosis at the end of 5 days of reperfusion compared with the control. Decreased inflammatory cell infiltration and MPO activity indicated post-con attenuated acute inflammatory reaction caused by I/R. This study reports for the first time that ischemic post-con effectively attenuates skin flap I/R injury. With further study, post-con may eventually be clinically applicable for the I/R injury as an "after-injury strategy."

Topics: Animals; Male; Necrosis; Peroxidase; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Reperfusion Injury; Surgical Flaps

Nitroalkene derivatives of linoleic acid (nitrolinoleic acid; LNO2) and nitro-oleic acid (OA-NO2) are endogenous lipid products with potent anti-inflammatory properties. The present study was undertaken to evaluate the therapeutic potential of OA-NO2 in a mouse model of renal ischemia-reperfusion (I/R) injury. B6129SF2/J mice were subjected to bilateral renal ischemia for 30 min, followed by 24 h of reperfusion. Fifty minutes after ischemia, mice received intraperitoneal (ip) injections of OA-NO2 (500 microg/kg; I/R OA-NO2), vehicle for OA-NO2 (i.e., 0.8 ml/kg ethanol; I/R veh), or oleic acid (500 microg/kg; I/R OA) every 6 h during the 24-h recovery period. A sham-operated group was not subjected to ischemia and received 0.8 ml/kg ethanol ip every 6 h during the 24-h recovery period (sham veh). While plasma urea and creatinine were elevated (P<0.05) in I/R veh vs. sham veh mice, the severity was less (P<0.05) in I/R OA-NO2 animals. Indices of histological damage, polymorphonucleocyte infiltration, together with expression of intracellular adhesion molecule-1, interleukin-1beta, and tumor necrosis factor-alpha, p47(phox), and gp91(phox) were greater in I/R veh vs. sham veh mice, but were attenuated (P<0.05) in I/R OA-NO2 animals. Because indices of renal dysfunction were similar between I/R veh and I/R OA mice (P>0.05), but less (P<0.05) in I/R OA-NO2 animals compared with both groups, protection from bilateral renal ischemia is afforded by the nitrated but not free form of oleic acid. Together, delayed administration of nitrated fatty acid OA-NO2 attenuates renal I/R injury in the mouse likely via inhibition of the inflammatory response.

Topics: Acute Kidney Injury; Animals; Creatinine; Gene Expression; Injections, Intraperitoneal; Intercellular Adhesion Molecule-1; Interleukin-1beta; Kidney; Male; Membrane Glycoproteins; Mice; Mice, Inbred Strains; NADPH Oxidase 2; NADPH Oxidases; Nephritis; Nitrogen; Oleic Acids; Oxidative Stress; Peroxidase; Reperfusion Injury; Urea

To determine whether Nigella sativa prevents hepatic ischemia-reperfusion injury to the liver.. Thirty rats were divided into three groups as sham (Group 1), control (Group 2), and Nigella sativa (NS) treatment group (Group 3). All rats underwent hepatic ischemia for 45 min followed by 60 min period of reperfusion. Rats were intraperitoneally infused with only 0.9% saline solution in group 2. Rats in group 3 received NS (0.2 mL/kg) intraperitoneally, before ischemia and before reperfusion. Blood samples and liver tissues were harvested from the rats, and then the rats were sacrificed. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) levels were determined. Total antioxidant capacity (TAC), catalase (CAT), total oxidative status (TOS), oxidative stress index (OSI) and myeloperoxidase (MPO) in hepatic tissue were measured. Also liver tissue histopathology was evaluated by light microscopy.. The levels of liver enzymes in group 3 were significantly lower than those in the group 2. TAC in liver tissue was significantly higher in group 3 than in group 2. TOS, OSI and MPO in hepatic tissue were significantly lower in group 3 than the group 2. Histological tissue damage was milder in the NS treatment group than that in the control group.. Our results suggest that Nigella sativa treatment protects the rat liver against to hepatic ischemia-reperfusion injury.

Topics: Animals; Antioxidants; Aspartate Aminotransferases; Catalase; Disease Models, Animal; Infusions, Parenteral; L-Lactate Dehydrogenase; Liver; Liver Diseases; Male; Nigella sativa; Oxidative Stress; Peroxidase; Plant Extracts; Rats; Rats, Wistar; Reperfusion Injury; Time Factors

Hepatic ischemia/reperfusion injury (IRI) may cause acute inflammatory damage, producing significant organ dysfunction, an important problem for liver transplantation. Previous studies have demonstrated that Tetrandrine (Tet), a component of traditional Chinese herbal medicine, shows protective effects to scavenge active oxygen radicals and inhibit lipid peroxidation. In this study, we examined whether Tet has a protective effect on mouse hepatic IRI.. Male C57BL/6 mice were divided into sham, ischemic, and Tet-treated groups; 90 minutes of warm ischemia was performed on the left liver lobe. Tet (20 mg/kg) was injected intraperitoneally at 1 hour before ischemia with a second intravenous dose was injected just before reperfusion. Blood and liver samples were collected at 6 hours after reperfusion. We analyzed the hepatocellular injury, oxidative stress, neutrophil recruitment, and tumor necrosis factor-alpha (TNF-alpha) generation associated with hepatic IRI.. Undergoing 90 minutes of ischemia and 6 hours reperfusion caused dramatic injuries in mouse livers. Administration of Tet (20 mg/kg) reduced serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH); decreased liver edema, TNF-alpha, myeloperoxidase (MPO) and malondialdehyde (MDA) contents; and ameliorated the down-regulation of superoxide dismutase (SOD) activity.. Tet showed protective effects on mouse hepatic IRI.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Benzylisoquinolines; Calcium Channel Blockers; Drugs, Chinese Herbal; Edema; Liver Circulation; Male; Malondialdehyde; Mice; Mice, Inbred C57BL; Peroxidase; Reperfusion Injury; Superoxide Dismutase

This study was conducted to investigate putative antagonism of integrin receptors alphaMbeta2 and alphaLbeta2 by a novel coumarin derivative (BOL-303225-A), its efficacy in-vivo after retinal ischaemia-reperfusion injury, and its bioavailability in rat plasma. A cellular adhesion assay in Jurkat and U937 cells, and a flow cytometry assay with an antibody against the beta2 subunit were conducted. BOL-303225-A bioavailability in rat plasma and the retinal levels of myeloperoxidase (MPO) after ischaemia-reperfusion injury were evaluated after oral administration (10 mg kg(-1)). In-vitro cell viability assays revealed no cytotoxicity for BOL-303225-A over a wide dose range, and IC50 values of 32.3 +/- 1.5 muM and 84.95 +/- 2.3 muM were found for Jurkat and U937 cells, respectively. The drug showed specific binding to the alphaMbeta2 and alphaLbeta2 integrin receptors expressed by U937 and Jurkat cells, respectively, producing a fluorescence shift towards lower values in a concentration-dependent manner. The pharmacokinetic profile of BOL-303225-A exhibited rapid absorption following oral administration in the rat. A significant reduction of retinal MPO levels was observed in drug-treated rats. This study demonstrated that BOL-303225-A acts as an antagonist of the integrin alphaLbeta2 and alphaMbeta2 receptors, suggesting that this drug could be used for ocular diseases such as diabetic retinopathy.

Topics: Administration, Oral; Animals; Anti-Inflammatory Agents; Biological Availability; Cell Adhesion; Cell Survival; Coumarins; Dose-Response Relationship, Drug; Flow Cytometry; Humans; Jurkat Cells; Lymphocyte Function-Associated Antigen-1; Macrophage-1 Antigen; Male; Peroxidase; Protein Binding; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Retinal Diseases; U937 Cells

Previous reports have confirmed that edaravone has protective effects against ischemia-reperfusion (IR) injury of many organs. In this study, we investigated the effect of edaravone on preventing IR injury of the lung in a canine lung transplantation model.. Twelve weight-matched pairs of random-bred dogs were randomized into two groups. Within each pair, one dog served as donor and the other as recipient. In the study group, prostaglandin E1(PGE1)(8 microg/kg) was injected into the donor pulmonary artery (PA) before occlusion and the donor lungs were flushed with 1.0 L of LPD solution containing edaravone (10 mg/kg) and stored in the same LPD solution at a temperature of 1 degrees C for 8 hours. The left single lung transplantation was then performed and recipients received intravenous injection with edaravone (10 mg/kg) at the onset of reperfusion. In the control group, edaravone was substituted by the same volume of sterile saline solution. Another six dogs were obtained as normal control group in which left lungs were dissected after thoracotomy without an IR injury. One hour after reperfusion, or after dissection of the left lung, the right lung was excluded from perfusion and ventilation after which, cardiopulmonary parameters were measured. Wet/dry ratios, malondialdehyde (MDA) and myeloperoxidase (MPO) levels were assessed and histological analysis of lung tissue performed at the same time.. All animals survived until the end of the experiment. The study group showed significantly decreased wet/dry ratios (treated: (74.1 +/- 4.2)% vs control: (86.8 +/- 5.2)%, P < 0.01), MDA levels (treated: 0.50 +/- 0.08 vs. control: 0.88 +/- 0.15, P < 0.01) and MPO activity (treated: 0.23 +/- 0.05 vs. control: 0.43 +/- 0.07, P < 0.01) compared to the control group two hours after occlusion of the right side. In the control group, pulmonary vascular resistance (PVR) was increased markedly and arterial oxygen partial pressure deteriorated significantly after exclusion of the right side compared to those in the treatment group.. Edaravone attenuates IR-induced lung injury and preserves lung function by inhibiting oxidative stress and decreasing leukocyte extravasation in a canine lung transplantation model.

Topics: Animals; Antipyrine; Disease Models, Animal; Dogs; Edaravone; Lipid Peroxidation; Lung; Lung Transplantation; Nitric Oxide; Oxidative Stress; Peroxidase; Reperfusion Injury

Cardiopulmonary bypass has been shown to exert an inflammatory response within the lung, often resulting in postoperative pulmonary dysfunction. Several studies have shown that adenosine A(2A) receptor activation attenuates lung ischemia-reperfusion injury; however, the effect of adenosine A(2A) receptor activation on cardiopulmonary bypass-induced lung injury has not been studied. We hypothesized that specific adenosine A(2A) receptor activation by ATL313 would attenuate inflammatory lung injury after cardiopulmonary bypass.. Adult male Sprague-Dawley rats were randomly divided into 3 groups: 1) SHAM group (underwent cannulation + heparinization only); 2) CONTROL group (underwent 90 minutes of normothermic cardiopulmonary bypass with normal whole-blood priming solution; and 3) ATL group (underwent 90 minutes of normothermic cardiopulmonary bypass with ATL313 added to the normal priming solution).. There was significantly less pulmonary edema and lung injury in the ATL group compared with the CONTROL group. The ATL group had significant reductions in bronchoalveolar lavage interleukin-1, interleukin-6, interferon-gamma, and myeloperoxidase levels compared with the CONTROL group. Similarly, lung tissue interleukin-6, tumor necrosis factor-alpha, and interferon-gamma were significantly decreased in the ATL group compared with the CONTROL group. There was no significant difference between the SHAM and ATL groups in the amount of pulmonary edema, lung injury, or levels of proinflammatory cytokines.. The addition of a potent adenosine A(2A) receptor agonist to the normal priming solution before the initiation of cardiopulmonary bypass significantly protects the lung from the inflammatory effects of cardiopulmonary bypass and reduces the amount of lung injury. Adenosine A(2A) receptor agonists could represent a new therapeutic strategy for reducing the potentially devastating consequences of the inflammatory response associated with cardiopulmonary bypass.

Topics: Adenosine A2 Receptor Agonists; Animals; Blood Gas Analysis; Bronchoalveolar Lavage Fluid; Cardiopulmonary Bypass; Interferon-gamma; Interleukin-1; Interleukin-6; Lung; Lung Diseases; Male; Peroxidase; Piperidines; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

To investigate the effects and possible mechanisms of Wy14643 on hepatic ischemia-reperfusion (I/R) injury in rats.. Thirty male Sprague-Dawley rats weighing 220-280 g were randomly divided into five experimental groups: sham group (G1, n=6): a sham operation was performed (except for liver I/R); I/R-untreated group (G2, n=6): rats underwent liver ischemia for 90 min followed by reperfusion for 4 h; and I/R+Wy14643 groups (G3, G4, G5; n=6): after the same surgical procedure as in group 2, animals were pretreated with Wy14643 at the dose of 1, 5 and 10 mg/kg 1 h before ischemia, respectively. Hepatic ischemia-reperfusion (I/R) was induced by clamping blood supply to the left lateral and median lobes of the liver for 90 min, and atraumatic clamp was removed for 4 h reperfusion. Blood samples and liver tissues were obtained at the end of reperfusion to assess serum and hepatic tissue homogenate aminotransferase (ALT), aspartate aminotransferase (AST), myeloperoxidase (MPO), serum interleukin-1beta (IL-1beta) and tumor necrosis factor alpha (TNF-alpha), as well as activity of superoxide dismutase (SOD) and content of malondialdehyde (MDA) in the hepatic tissue homogenate.. Hepatic I/R induced a significant increase in the serum levels of ALT, AST, TNF-alpha, IL-1beta and MPO, as well as the levels of ALT, AST and MDA in the liver tissue homogenate, which were reduced by pretreatment with Wy14643 at the dose of 1, 5 and 10 mg/kg, respectively. The activity of SOD in the liver tissue homogenate was decreased after hepatic I/R, which was enhanced by Wy14643 pretreatment. In addition, serum and liver tissue homogenate ALT and AST in the Wy14643 10 mg/kg group were lower than in the Wy14643 1 mg/kg and 5 mg/kg groups, respectively.. Wy14643 pretreatment exerts significant protection against hepatic I/R injury in rats. The protective effects are possibly associated with enhancement of anti-oxidant and inhibition inflammation response.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Disease Models, Animal; Hepatitis; Interleukin-1beta; Liver; Male; Malondialdehyde; Oxidative Stress; Peroxidase; PPAR alpha; Pyrimidines; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase; Tumor Necrosis Factor-alpha

Ischemia/reperfusion injury (IRI) is a major problem in intestinal transplantation. Toll-like receptor 4 (TLR4) has been implicated as a possible link between the innate and adaptive immune systems, however little data exists regarding TLR4 in intestinal IRI. The goal of this study is to evaluate the involvement of TLR4 in intestinal IRI and to assess the effect on T cell related chemokine programs.. C57BL6 mice underwent 100 minutes of warm intestinal ischemia by SMA clamping. Control WT mice underwent laparotomy without vascular occlusion. Separate survival and analysis groups were performed, and intestinal tissue was harvested at 1 hour, 2 hours, 4 hours, and 24 hours post-reperfusion. Analysis included histology, CD3 immunostaining, myeloperoxidase activity, Western blot, and PCR.. Survival was significantly worse in the IRI group vs control (50% vs. 100%). IRI caused severe histopathological injury including mucosal erosions and villous congestion and hemorrhage. Myeloperoxidase activity increased in a time-dependent manner after IRI (2.71 0.25 at 1 hour, 2.92 0.25 at 2 hours, 4 0.16 at 4 hours, 5.1 0.25 at 24 hours vs 0.47 0.11 controls, P < .05). Protein expression of TLR4 followed by NF-kappaB was increased after IRI. Additionally, mRNA production of IP-10, MIP-2, MCP-1, and RANTES was increased at all time-points, as was mRNA for ICAM-1 and E-selectin.. This study is the first to demonstrate increased expression of TLR4 and NF-kappaB after warm intestinal IRI. This detrimental cascade may be initiated by TLR4 via NF-kappaB signaling pathways, implicating TLR4 as a potential therapeutic target for the prevention of intestinal IRI.

Topics: Actins; Animals; Chemokines; DNA Primers; Immunohistochemistry; Intestinal Mucosa; Intestines; Male; Mice; Mice, Inbred C57BL; Muscle, Smooth; Peroxidase; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA; RNA, Messenger; Survivors; Toll-Like Receptor 4

Intestinal ischemia-reperfusion (I/R) is an important event in the pathogenesis of multiple organ dysfunction syndrome (MODS). The aim of this study is to determine the effects of ginsenoside Rb1 on liver injury induced by intestinal I/R in rats. Adult male Wistar rats were randomly divided into four groups: (1) a control, sham-operated group (sham group); (2) an intestinal I/R group subjected to 1 h intestinal ischemia and 2 h reperfusion (I/R group); (3) a group treated with 20 mg/kg ginsenoside Rb1 before reperfusion (Rb1-20 group); and (4) a group treated with 40 mg/kg ginsenoside Rb1 before reperfusion (Rb1-40 group). Liver and intestinal histology was observed. Aspartate aminotransferase (AST), alanine aminotransferase (ALT) level in serum and malondialdehyde (MDA) level in intestinal tissues were measured. Myeloperoxidase (MPO), TNF-alpha, MDA level and immunohistochemical expression of NF-kgr;B and intracellular adhesion molecule-1 (ICAM-1) in liver tissues was assayed. In addition, a western blot analysis of liver NF-kappaB expression was performed. Results indicated intestinal I/R induced intestinal and liver injury, which was characterized by increase of AST and ALT in serum, MDA level in intestine, MPO, TNF-alpha and MDA level and ICAM-1 and NF-kappaB expression in the liver tissues. Ginsenoside Rb1 (20, 40 mg/kg) ameliorated liver injury, decreased MPO, TNF-alpha and MDA level, NF-kappaB and ICAM-1 expression in liver tissues. In conclusion, ginsenoside Rb1 ablated liver injury induced by intestinal I/R by inhibiting NF-kappaB activation.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Biomarkers; Ginsenosides; Intercellular Adhesion Molecule-1; Intestinal Mucosa; Intestines; Ischemia; Liver; Liver Diseases; Male; Malondialdehyde; NF-kappa B; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Tumor Necrosis Factor-alpha

Thermal injury causes a breakdown in the intestinal mucosal barrier due to ischemia reperfusion injury, which can induce bacterial translocation (BT), sepsis, and multiple organ failure in burn patients. The aim of this study was to investigate the effect of ethyl pyruvate (EP) on intestinal oxidant damage and BT in burn injury.. Thirty-two rats were randomly divided into four groups. The sham group was exposed to 21 degrees C water and injected intraperitoneal with saline (1 mL/100 g). The sham + EP group received EP (40 mg/kg) intraperitoneally 6 h after the sham procedure. The burn group was exposed to thermal injury and given intraperitoneal saline injection (1 mL/100 g). The burn + EP group received EP (40 mg/kg) intraperitoneally 6 h after thermal injury. Twenty-four hours later, tissue samples were obtained from mesenteric lymph nodes, spleen, and liver for microbiological analysis and ileum samples were harvested for biochemical analysis.. Thermal injury caused severe BT in burn group. EP supplementation decreased BT in mesenteric lymph nodes and spleen in the burn + EP group compared with the burn group (P < 0.05). Also, burn caused BT in liver, but this finding was not statistically significant among all groups. Thermal injury caused a statistically significant increase in malondialdehyde and myeloperoxidase levels, and EP prevented this effects in the burn + EP group compared with the burn group (P < 0.05).. Our data suggested that EP can inhibit the BT and myeloperoxidase and malondialdehyde production in intestine following thermal injury, suggesting anti-inflammatory and anti-oxidant properties of EP.

Topics: Animals; Bacterial Translocation; Burns; Intestinal Mucosa; Intestines; Liver; Lymph Nodes; Malondialdehyde; Oxidative Stress; Peroxidase; Pyruvates; Rats; Rats, Wistar; Reperfusion Injury; Spleen

[corrected] The goal of this experimental study was to investigate whether erdosteine has a protective effect against lung injury as a remote organ after hind-limb ischemia-reperfusion (I/R).. The rats were divided into three groups: control, I/R, and I/R + erdosteine. After the experimental procedure, nitric oxide (NO) levels, myeloperoxidase (MPO), adenosine deaminase (ADA), and the activities of xanthine oxidase (XO) were determined on the lung tissue. The levels of NO and activities of MPO were also measured on the bronchial alveolar lavage (BAL). In addition, the lung tissue was examined by histopathology.. The lung tissue ADA and XO activities were increased in the I/R group compared with the control group (P < 0.05). In the I/R group, the levels of NO were higher than the control group (P < 0.05), whereas the erdosteine treatment did not alter the NO levels (P < 0.05). The MPO activities increased after I/R in the I/R group compared to both control and I/R + erdosteine group (P < 0.05). The activity of MPO increased in the IR group in comparison with the control group in BAL (P < 0.05). The activity of MPO in the I/R + erdosteine group was significantly lower than the I/R group in BAL (P < 0.05). NO levels increased in all I/R groups compared to control group in BAL (P < 0.05). However, treatment of erdosteine significantly decreased NO levels compared to I/R group (P < 0.05). The animals of the I/R group had total destruction of normal alveolar structure with the intense presence of infiltrating neutrophils and mononuclear phagocytes in histopathological examination. The rat lung exhibited mild degrees of destruction in the erdosteine group.. As a result, erdosteine may be a protective effect for lung injury, decreasing oxidative stress and neutrophil accumulation after hind-limb I/R in rats.

Topics: Adenosine Deaminase; Animals; Antioxidants; Bronchoalveolar Lavage Fluid; Hindlimb; Male; Neutrophils; Nitric Oxide; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Respiratory Distress Syndrome; Thioglycolates; Thiophenes; Xanthine Oxidase

Ergothioneine (EGT) is a natural compound that is synthesized by soil bacteria in fungal substrates and exhibits antioxidant functions in many cell models. The purpose of this study was to investigate the effect of EGT on mesenteric ischemia and reperfusion injury.. Rats were supplemented with or without l-ergothioneine (10 mg/kg/d) for 15 days prior to intestinal ischemia. Animals were subjected to ischemia induced by clamping the superior mesenteric artery for 60 min followed by reperfusion. Serum tumor necrosis factor (TNF)-alpha and interleukin-1beta (IL-1beta) levels, tissue malondialdehide (MDA), myleoperoxidase (MPO), and heat shock protein (HSP) 70 levels, as well as histological findings, were evaluated after 1, 2, and 4 h of reperfusion.. Serum TNF-alpha and IL-1beta levels, and tissue MDA and MPO activities at 1, 2 and 4 h after reperfusion in the EGT group, were significantly lower than the control group (P < 0.05). Tissue HSP-70 levels of the study group were significantly greater than the control group at any time point of reperfusion. No significant differences in tissue damage including morphological changes ranging from villous denudation to focal necrosis, ulceration, hemorrhage, and architectural disintegration at 1 and 2 h after reperfusion exist between the two groups; however, after 4 h of reperfusion, the tissue damage based on histopathologic scores by Chiu was considerably lower in the study group (P < 0.05). After 4 h of reperfusion, focal epithelial lifting and occasional areas of denuded villi could be seen in the samples of the treated animals, thus preserving villous height and mucosal architecture.. EGT attenuates mesenteric ischemia reperfusion injury in rat intestine by increasing tissue HSP-70 and decreasing TNF-alpha, IL-1beta, MDA, and MPO levels. EGT also improves morphological alterations, which occurred after IR injury after prolonged periods of reperfusion.

Topics: Animals; Antioxidants; Ergothioneine; HSP70 Heat-Shock Proteins; Interleukin-1beta; Intestinal Mucosa; Intestines; Lipid Peroxidation; Male; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Splanchnic Circulation; Tumor Necrosis Factor-alpha

To determine whether the protective effect of melatonin in testicular ischemia/reperfusion (IR) injury is mediated by the proinflammatory molecules.. Experimental study.. University pharmacology laboratory.. Fifty-six 8-week-old male Wistar albino rats.. Left testicular artery and vein was occluded for 1 hour, followed by 3 hours or 24 hours of reperfusion. Melatonin (10 mg/kg IP) or vehicle (1% ethanol in saline) was given 10 minutes before ischemia.. Malondialdehyde (MDA), protein carbonyl (PC) content, myeloperoxidase (MPO) activity, and proinflammatory cytokines TNF-alpha, IL-1beta, and IL-6 were examined in testicular tissue after 3 hours of reperfusion. Histologic examination was made after 24 hours of reperfusion.. The MDA, PC, and MPO levels in testicular tissue increased significantly after IR, but the proinflammatory cytokine levels did not change. Melatonin treatment decreased lipid and protein oxidation and ameloriated histopathologic alterations induced by IR without any change in proinflammatory cytokine levels.. The protective effect of melatonin on IR-induced testiculary injury is related to its antioxidant properties but not to proinflammatory cytokines.

Topics: Animals; Antioxidants; Cytokines; Cytoprotection; Inflammation Mediators; Interleukin-1beta; Interleukin-6; Male; Malondialdehyde; Melatonin; Peroxidase; Placebos; Protein Carbonylation; Rats; Rats, Wistar; Reperfusion Injury; Testis; Tumor Necrosis Factor-alpha

Liver ischemia/reperfusion has been shown to result in injury of remote organs such as the heart and lungs. Whether or not acute liver injury also results in kidney injury has so far not been adequately addressed. In anesthetized Wistar rats, partial (70%) normothermic hepatic ischemia was applied for 75 min. After 24 h of reperfusion, renal injury was assessed by histology, creatinine and blood urea nitrogen (BUN) serum concentrations, renal expression of proinflammatory genes [quantitative real-time polymerase chain reaction (qRT-PCR)], caspase-3 activation (Western blot), and neutrophil accumulation (myeloperoxidase assay). Twenty-four hours after hepatic ischemia, creatinine (0.57+/-0.06 vs. 0.32+/-0.04 mg/dL) and BUN (40.7+/-15.3 vs. 14.3+/-2.0 mg/dL) were increased when compared to sham. qRT-PCR revealed higher renal intercellular adhesion molecule-1 gene expression following hepatic ischemia (166+/-45% when compared to sham) but no differences in renal monocyte chemoattractant protein-1, macrophage inflammatory protein-2, and inducible NO synthase expression. In both groups, kidneys showed no morphological damage and no increase in caspase-3 and myeloperoxidase activity. Severe hepatic ischemia results in a moderate impairment of renal function in rats but does not trigger an inflammatory response in the kidney and does not result in morphological damage of the kidney.

Topics: Animals; Apoptosis; Caspase 3; Creatinine; Immunoblotting; Kidney; Liver; Male; Peroxidase; Rats; Rats, Wistar; Renal Insufficiency; Reperfusion Injury

Leukocyte transmigration across endothelial and extracellular matrix protein barriers is dependent on adhesion and focal matrix degradation events. In the present study we investigated the role of metalloproteinase-9 (MMP-9/gelatinase B) in liver ischemia/reperfusion (I/R) injury using MMP-9-deficient (MMP-9(-/-)) animals and mice treated with a specific anti-MMP-9 neutralizing antibody or with a broad gelatinase inhibitor for both MMP-9 and metalloproteinase-2 (MMP-2/gelatinase A). Compared to wild-type mice, MMP-9(-/-) mice and mice treated with an anti-MMP-9 antibody showed significantly reduced liver damage. In contrast, mice treated with a broad gelatinase inhibitor showed rather inferior protection against I/R injury and were characterized by persistent ongoing liver inflammation, suggesting that MMP-2 and MMP-9 may have distinct roles in this type of injury. MMP-9 was mostly detected in Ly-6G and macrophage antigen-1 leukocytes adherent to the vessel walls and infiltrating the damaged livers of wild-type mice after liver I/R injury. Leukocyte traffic and cytokine expression were markedly impaired in livers of MMP-9(-/-) animals and in livers of mice treated with anti-MMP-9 antibody after I/R injury; however, initiation of the endothelial adhesion cascades was similar in both MMP-9(-/-) and control livers. We also showed that MMP-9-specific inhibition disrupted neutrophil migration across fibronectin in transwell filters and depressed myeloperoxidase (MPO) activation in vitro.. These results support critical functions for MMP-9 in leukocyte recruitment and activation leading to liver damage. Moreover, they provide the rationale for identifying inhibitors to specifically target MMP-9 in vivo as a potential therapeutic approach in liver I/R injury.

Topics: Animals; Antibodies; Cell Movement; Enzyme Inhibitors; Fibronectins; Intercellular Adhesion Molecule-1; Leukocytes; Liver Diseases; Male; Matrix Metalloproteinase 9; Matrix Metalloproteinase Inhibitors; Mice; Mice, Knockout; Neutrophils; Peroxidase; Reperfusion Injury; Vascular Cell Adhesion Molecule-1; Warm Ischemia

Ischaemia/reperfusion is a major cause of acute kidney injury and can result in poor long-term graft function. Although most of the patients with acute kidney injury recover their renal function, significant portion of patients suffer from progressive deterioration of renal function. A persistent inflammatory response might be associated with long-term changes following acute ischaemia/reperfusion. Macrophages are known to infiltrate into tubulointersitium in animal models of chronic kidney disease. However, the role of macrophages in long-term changes after ischaemia/reperfusion remains unknown. We aimed to investigate the role of macrophages on the development of tubulointerstitial fibrosis and functional impairment following acute ischaemia/reperfusion injury by depleting macrophages with liposome clodronate.. Male Sprague-Dawley rats underwent right nephrectomy and clamping of left renal vascular pedicle or sham operation. Liposome clodronate or phosphate buffered saline was administered for 8 weeks. Biochemical and histological renal damage and gene expression of various cytokines were assessed at 4 and 8 weeks after ischaemia/reperfusion.. Ischaemic/reperfusion injury resulted in persistent inflammation and tubulointerstital fibrosis with decreased creatinine clearance and increased urinary albumin excretion at 4 and 8 weeks. Macrophage depletion attenuated those changes. This beneficial effect was accompanied with a decrease in gene expression of inflammatory and profibrotic cytokines.. These results suggest that macrophages play an important role in mediating persistent inflammation and fibrosis after ischaemia/reperfusion leading to a development of chronic kidney disease. Strategies targeting macrophage infiltration or activation can be useful in the prevention of development of chronic kidney disease following ischaemic injury.

Topics: Animals; Cell Movement; Chemokine CCL2; Disease Models, Animal; Fibrosis; Interleukin-1beta; Interleukin-6; Kidney; Macrophages; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; RNA, Messenger; Transforming Growth Factor beta1; Tumor Necrosis Factor-alpha

The current study was undertaken to elucidate the possible therapeutic effects of hyperoxygenated solution (HOS) preconditioning on lung injury induced by intestinal ischemia/reperfusion (I/R) in rabbits.. Eighty rabbits were randomly divided into four groups (n = 20 each) as follows: (1) control group in which sham operation was performed (sham group), (2) HOS pretreatment group and sham operation (HOS + sham group), (3) ischemia/reperfusion group (I/R group), (4) HOS pretreatment and ischemia/reperfusion group (HOS + I/R group). Intestinal I/R model was produced by clamping superior mesenteric artery with an atraumatic vascular clamp for 1 h, and followed by reperfusion for 2 h. Animals in HOS + sham group and HOS + I/R group received intravenous HOS infusion (20 mL/kg, 10 mL/kg.h for 2 h) every day for 5 d before operation, and animals in sham group and I/R group received the same amount of normal saline in the same way. At the end of reperfusion, 8 animals from every group were sacrificed and histopathological changes of lung were observed; pulmonary edema, lung myeloperoxidase activity, superoxide dismutase activity, and malondialdehyde levels in lung tissues were also detected. The rest 12 animals in every group underwent 60 min of intestinal ischemia followed by 72 h of reperfusion, and effects of HOS pretreatment on survival in rabbits with lung injury induced by intestinal I/R was observed.. When rabbits were subjected to 60 min of intestinal ischemia, a high incidence of mortality was observed within 24 h. In this situation, HOS preconditioning before the start of ischemia/reperfusion significantly reduced the mortality. HOS preconditioning also decreased lung wet/dry ratio, neutrophil infiltration, lipid membrane peroxidation, and increased superoxide dismutase activity in the lungs after intestinal I/R compared with the I/R-treated rabbit lungs without HOS treatment. Histopathological analysis also indicated the effectiveness of HOS pretreatment.. HOS preconditioning could preserve superoxide dismutase activity, decrease lipid membrane peroxidation and neutrophil infiltration in the lungs, then ameliorate the deleterious changes in pulmonary injury induced by intestinal I/R.

Topics: Animals; Cell Movement; Dose-Response Relationship, Drug; Infusions, Intravenous; Intestines; Ischemic Preconditioning; Lipid Peroxidation; Lung; Male; Malondialdehyde; Neutrophils; Oxygen; Ozone; Peroxidase; Pulmonary Edema; Rabbits; Random Allocation; Reperfusion Injury; Respiratory Distress Syndrome; Sodium Chloride; Superoxide Dismutase

The aim of this experimental study was to investigate whether dimethylsulfoxide (DMSO) has protective effects on spinal cord ischemia-reperfusion (I/R) injury. New Zealand rabbits were enrolled in the study. In addition to the control group, the study group received 0.1 mL/kg DMSO prior to ischemia. Blood samples were taken to obtain nitrite-nitrate levels during the surgical procedure. After neurological evaluation at 24 hr of reperfusion, lumbar spinal cords were removed for electron microscopic evaluation and malondialdehyde and myeloperoxidase measurements. The mean Tarlov score of the DMSO group was higher than that of the control group. Electron microscopic examination was carried out with tissue samples at 24 hr of reperfusion. The DMSO group had better preservation with the electron microscopic scoring compared to the control group. Malondialdehyde and myeloperoxidase levels were decreased in the DMSO group compared to the control group. Nitrite-nitrate levels were also lower in the DMSO group compared to control at 5 and 30 min of reperfusion. This study demonstrates a considerable neuroprotective effect of DMSO on neurological, biochemical, and histopathological analyses during periods of spinal cord I/R injury in rabbits. Although there was a difference between the DMSO and control groups in all measured parameters in our study, this was not statistically significant. DMSO deserves further investigation related with spinal cord ischemia and reperfusion. We should also consider the effect of DMSO when we use it as a solvent or vehicle during experimental I/R models.

Topics: Animals; Aorta, Abdominal; Dimethyl Sulfoxide; Disease Models, Animal; Free Radical Scavengers; Ligation; Malondialdehyde; Neuroprotective Agents; Nitrates; Nitrites; Peroxidase; Rabbits; Reperfusion Injury; Solvents; Spinal Cord; Spinal Cord Ischemia; Time Factors; Tyrosine

Dimemorfan, an antitussive and a sigma-1 (sigma(1)) receptor agonist, has been reported to display neuroprotective properties. We set up an animal model of ischemic stroke injury by inducing cerebral ischemia (for 1 h) followed by reperfusion (for 24 h) (CI/R) in rats to examine the protective effects and action mechanisms of dimemorfan against stroke-induced damage. Treatment with dimemorfan (1.0 microg/kg and 10 microg/kg, i.v.) either 15 min before ischemia or at the time of reperfusion, like the putative sigma(1) receptor agonist, PRE084 (10 microg/kg, i.v.), ameliorated the size of the infarct zone by 67-72% or 51-52%, respectively, which was reversed by pre-treatment with the selective sigma(1) receptor antagonist, BD1047 (20 microg/kg, i.v.). Major pathological mechanisms leading to CI/R injury including excitotoxicity, oxidative/nitrosative stress, inflammation, and apoptosis are all downstream events initiated by excessive accumulation of extracellular glutamate. Dimemorfan treatment (10 microg/kg, i.v., at the time of reperfusion) inhibited the expressions of monocyte chemoattractant protein-1 and interleukin-1beta, which occurred in parallel with decreases in neutrophil infiltration, activation of inflammation-related signals (p38 mitogen-activated protein kinase, nuclear factor-kappaB, and signal transducer and activator of transcription-1), expression of neuronal and inducible nitric oxide synthase, oxidative/nitrosative tissue damage (lipid peroxidation, protein nitrosylation, and 8-hydroxy-guanine formation), and apoptosis in the ipsilateral cortex after CI/R injury. Dimemorfan treatment at the time of reperfusion, although did not prevent an early rise of glutamate level, significantly prevented subsequent glutamate accumulation after reperfusion. This inhibitory effect was lasted for more than 4 h and was reversed by pre-treatment with BD1047. These results suggest that dimemorfan activates the sigma(1) receptor to reduce glutamate accumulation and then suppresses initiation of inflammation-related events and signals as well as induction of oxidative and nitrosative stresses, leading to reductions in tissue damage and cell death. In conclusion, our results demonstrate for the first time that dimemorfan exhibits protective effects against ischemic stroke in CI/R rats probably through modulation of sigma(1) receptor-dependent signals to prevent subsequent glutamate accumulation and its downstream pathologic events.

Topics: Analysis of Variance; Animals; Brain Infarction; Brain Ischemia; Chemokine CCL2; Disease Models, Animal; Dose-Response Relationship, Drug; Gene Expression Regulation; Glutamic Acid; Lipid Peroxidation; Male; Morphinans; Morpholines; NF-kappaB-Inducing Kinase; Nitric Oxide Synthase; Peroxidase; Protein Serine-Threonine Kinases; Rats; Rats, Long-Evans; Receptors, sigma; Reperfusion Injury; Sigma-1 Receptor; Signal Transduction; STAT1 Transcription Factor

The membrane forms of guanylyl cyclase (GC) serve as cell-surface receptors that synthesize the second messenger cGMP, which mediates diverse cellular processes. Rat kidney contains mRNA for the GC-G isoform, but the role of this receptor in health and disease has not been characterized. It was found that mouse kidney also contains GC-G mRNA, and immunohistochemistry identified GC-G protein in the epithelial cells of the proximal tubule and collecting ducts. Six hours after ischemia-reperfusion (I/R) injury, GC-G mRNA and protein expression increased three-fold and remained upregulated at 24 h. For determination of whether GC-G mediates I/R injury, a mutant mouse with a targeted disruption of the GC-G gene (Gucy2g) was created. At baseline, no histologic abnormalities were observed in GC-G(-/-) mice. After I/R injury, elevations in serum creatinine and urea were attenuated in GC-G(-/-) mice compared with wild-type controls, and this correlated with less tubular disruption, less tubular cell apoptosis, and less caspase-3 activation. Measures of inflammation (number of infiltrating neutrophils, myeloperoxidase activity, and induction of IL-6 and P-selectin) and activation of NF-kappaB were lower in GC-G(-/-) mice compared with wild-type mice. Direct transfer of a GC-G expression plasmid to the kidneys of GC-G(-/-) mice resulted in a dramatically higher mortality after renal I/R injury, further supporting a role for GC-G in mediating injury. In summary, GC-G may act as an early signaling molecule that promotes apoptotic and inflammatory responses in I/R-induced acute renal injury.

Topics: Acute Kidney Injury; Animals; Apoptosis; Disease Models, Animal; Epithelial Cells; Interleukin-6; Kidney; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophils; NF-kappa B; P-Selectin; Peroxidase; Receptors, Guanylate Cyclase-Coupled; Reperfusion Injury; RNA, Messenger

The purpose of this study was to observe and characterize colonic and lung lesions in horses subjected to experimental distension and decompression of the small colon. Sixteen healthy adult horses were divided into 2 groups: 9 horses that were subjected to distension of the small colon by means of a latex balloon surgically implanted in the lumen and inflated to a pressure of 40 mm Hg for 4 h, and 7 horses in which the balloon was implanted but not inflated. Colonic biopsy specimens were collected before balloon implantation, at the end of the period of obstruction, and 1.5 and 12 h after decompression and were examined for hemorrhage, edema, and neutrophil infiltration; myeloperoxidase (MPO) activity and hemoglobin concentration were measured as well. At the end of the experiment, lung samples were also collected and examined for neutrophil accumulation and MPO activity. The mucosa was not affected by luminal distension; lesions were restricted to the seromuscular layer. Neutrophil accumulation and edema were observed in the samples from both groups of horses but were greater in those from the distension group, in which there was also hemorrhage, fibrin deposition, and increased MPO activity in the seromuscular layer. Similarly, there was greater accumulation of neutrophils in the lung samples from the distension group than in those from the sham-operated group, as determined by histologic evaluation and MPO assay. These findings provide new evidence of reperfusion injury and a systemic inflammatory response, followed by remote lesions, in horses with intestinal obstruction.

Topics: Animals; Colonic Diseases; Female; Hemoglobins; Horse Diseases; Horses; Intestinal Obstruction; Lung; Male; Neutrophil Activation; Peroxidase; Random Allocation; Reperfusion Injury; Time Factors

Hepatic ischemia-reperfusion (HIR) is a severe condition that is seen after hepatic arterial injury and in hepatic grafts in living donor transplantation. HIR not only causes liver injury by lipid peroxidation, but also stimulates systemic and portal endotoxemia. Also, lipopolysaccharide (LPS) induces hepatic injury mediated by inducible nitric oxide synthase (iNOS). There is little knowledge on the role of specific iNOS inhibitors in prevention of HIR injury followed by LPS administration. The aim of this study on a LPS induced HIR model was to investigate the effect of aminoguanidine (AG) administration on hepatic tissue iNOS expression and lipid peroxidation when given before or after LPS.. Six groups were designed; A: Sham, B: HIR, C: HIR + AG, D: HIR + LPS, E: HIR + LPS + AG, F: HIR + AG + LPS. No substance was given to the rats in Group A and B. HIR injury was induced with vascular occlusion for 45 min and reperfusion for 45 min. Drugs were given intraperitoneally 10 min before reperfusion. Serum and tissue analysis for myeloperoxidase (MPO), and malondialdehyde (MDA), and tissue NA+/K+ adenosine 5'triphosphatases (ATPase) and tissue iNOS staining were performed. Permission for this study was obtained from the local Ethics Committee.. The level of MPO, MDA, and iNOS staining scores in Group B were significantly higher than Group A and ATPase was lower in Group B (P < 0.05). Contrary to results in Group C, results of MPO, MDA, and iNOS staining scores of Group D was higher than Group B (P < 0.05); however, although iNOS in Group C was lower than Group B, the difference was not significant (P > 0.05). MPO and MDA levels of Groups E and F were significantly lower than Group D. Level of ATPase in Group F was significantly different from Groups D and E. iNOS scoring was low in Group F compared with Group D (P < 0.05). MDA, MPO, and iNOS levels of Group F was lower than Group E, and ATPase of Group F was higher than Group E (P < 0.05).. The results of this study in a LPS induced HIR model showed that LPS after HIR aggravated HIR injury by increasing neutrophil activation and lipid peroxidation both in serum and liver tissue and iNOS in liver, and depleting energy in liver. AG, a selective iNOS inhibitor, ameliorated the negative effects of endotoxemia induced by LPS after HIR; however, energy depletion and iNOS expression in liver tissue were attenuated only when AG was administered prior to LPS. The findings of this study supported the hypothesis that LPS after HIR would aggravate HIR injury and AG would ameliorate this aggravated injury.

Topics: Animals; Disease Models, Animal; Endotoxemia; Enzyme Inhibitors; Guanidines; Lipid Peroxidation; Lipopolysaccharides; Liver; Liver Diseases; Male; Malondialdehyde; Nitric Oxide Synthase Type II; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Sodium-Potassium-Exchanging ATPase

Intestinal ischemia/reperfusion (I/R) produces reactive oxygen species (ROS) activating signal transduction and apoptosis. The aim of this study was to evaluate the effect of (-)-epigallocatechin-3-gallate (EGCG) administration in inhibition of apoptosis by attenuating the expression of NF-kB, c-Jun and caspace-3 in intestinal I/R. Thirty male wistar rats were used. Group A sham operation, B I/R, C I/R-EGCG 50 mg/kg ip. Intestinal ischemia was induced for 60 min by clamping the superior mesenteric artery. Malondialdehyde (MDA), myeloperoxidase (MPO), light histology, Fragment End Labelling of DNA (TUNEL), immunocytochemistry for NF-kB, c-Jun and caspace-3 analysis in intestinal specimens were performed 120 min after reperfusion. Apoptosis as indicated by TUNEL and Caspace-3, NF-kB and c-Jun was widely expressed in I/R group but only slightly expressed in EGCG treated groups. MDA and MPO showed a marked increase in the I/R group and a significant decrease in the EGCG treated group. Light histology showed preservation of architecture in the EGCG treated group. In conclusion, EGCG pre-treatment is likely to inhibit intestinal I/R-induced apoptosis by down-regulating the expression of NF-kB, c-Jun and caspase-3.

Topics: Animals; Apoptosis; Caspase 3; Catechin; Down-Regulation; In Situ Nick-End Labeling; Intestinal Mucosa; Intestines; Ischemia; Male; Malondialdehyde; Microscopy; Necrosis; NF-kappa B; Peroxidase; Proto-Oncogene Proteins c-jun; Rats; Rats, Wistar; Reperfusion Injury

Although IPC (ischaemic preconditioning) is considered as a protective strategy in HI/R (hepatic ischaemia/reperfusion), the mechanisms for this effect have not been fully elucidated. In the present study we investigate whether PPC (pharmacological preconditioning) by transient activation of A(1)R (adenosine A(1) receptor) protects against long-term HI/R and whether the protective effects of IPC depend on A(1)R activation and whether both preconditionings affect remote organs. Wistar rats underwent IPC and long-term HI/R. Another set of animals were pharmacologically preconditioned with the A(1)R-agonist CCPA [2-chloro-N(6)-cyclopentyladenosine; 0.1 mg/kg of body weight, i.p. (intraperitoneally)] 24 h before HI/R. In other groups, rats received an A(1)R-antagonist, DPCPX (1,3-dipropyl-8-cyclopentylxanthine; 0.1 mg/kg of body weight, i.p.) 24 h before HI/R. Hepatic damage was evaluated by transaminase [AST (aspartate transaminase), ALT (alanine transaminase)] release; inflammation was assessed by hepatic MPO (myeloperoxidase) and serum TNFalpha (tumour necrosis factor alpha) and NO; oxidative stress was estimated by MDA (malondialdehyde) and 4-HDA (4-hydroxyalkenals), SOD (superoxide dismutase) activity, GSH and ADA (adenosine deaminase) as adenosine metabolism. Both preconditionings protected liver and lung against HI/R as indicated by the reduction in transaminases, MPO, MDA+4-HDA, NO, TNFalpha and ADA activity as compared with HI/R (P<0.05). However, pre-treatment with DPCPX abolished the protective effects of IPC and PPC. Preconditionings induced a significant increase in hepatic MnSOD (manganese SOD) activity and NO generation compared with the sham group, and this activity was abolished by DPCPX pre-treatment. A(1)R activation induced hepatic delayed preconditioning and blockade of A(1)R abolished hepatic IPC. IPC, as well as PPC, were able to prevent lung damage. These protective effects are associated with a reduction in oxidative stress, inflammation and endogenous antioxidant preservation.

Topics: Adenosine; Adenosine A1 Receptor Agonists; Adenosine A1 Receptor Antagonists; Animals; Antioxidants; Drug Evaluation, Preclinical; Female; Glutathione; Ischemic Preconditioning; Liver; Oxidation-Reduction; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Receptor, Adenosine A1; Reperfusion Injury; Superoxide Dismutase; Tumor Necrosis Factor-alpha; Xanthines

1. The present study was designed to investigate the neuroprotective effect of trimetazidine (TMZ) following focal cerebral ischaemia-reperfusion (I/R) injury in rat forebrain. 2. Cerebral I/R injury was induced in rats by middle cerebral artery occlusion (MCAO) for 2 h, followed by reperfusion for 22 h. Trimetazidine (5 and 25 mg/kg, i.p.) was administered 1 h after induction of MCAO. The effects of TMZ were investigated by measuring neurological deficit, volume of infarct and brain swelling after 22 h reperfusion. Oxidative stress and inflammatory reactivity were assessed by estimating anti-oxidant markers and myeloperoxidase (MPO) activity in brain homogenates. Rectal temperature was measured during the study. The effects of TMZ on blood-brain barrier (BBB) permeability and apoptosis were also investigated in rat brain. Apoptosis was observed by DNA fragmentation studies using agarose gel electrophoresis. 3. Treatment with TMZ significantly (P < 0.01) reduced infarct volume and brain swelling. Superoxide dismutase (SOD) activity was reduced in ipsilateral hemispheres of vehicle (saline)-treated reperfused (RI) animals. Treatment with TMZ significantly restored SOD activity (P < 0.01) and glutathione levels (P < 0.05) after reperfusion compared with RI animals. Lipid peroxidation, MPO activity, BBB permeability and rectal temperature were all significantly (P < 0.01, P < 0.05 and P < 0.001, respectively) reduced in TMZ-treated animals compared with RI animals. 4. These results suggest that TMZ protects the brain against cerebral I/R injury and that this neuroprotective activity could be mediated by its anti-oxidant properties. The reduction in rectal temperature by TMZ treatment may be responsible for maintaining the delicate energy balance during I/R injury in rat brain and could have contributed to the neuroprotective activity of TMZ.

Topics: Animals; Antioxidants; Biomarkers; Blood-Brain Barrier; Body Temperature; Brain; Brain Edema; Brain Ischemia; Cerebral Infarction; Male; Neuroprotective Agents; Oxidative Stress; Permeability; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Trimetazidine

Inhibition of cytokines offers modest protection from injury in animal models of lung ischemia-reperfusion. Improved strategies would selectively inhibit the transcriptional activation response to oxidative stress. Mitogen-activated protein kinases (p38, c-jun N-terminal kinase, extracellular signal-regulated kinase) have been shown to be activated after oxidative stress and in animal models of acute inflammatory lung injury. We hypothesized that mitogen-activated protein kinase inhibition would block downstream transcriptional activation, providing robust protection from lung ischemia-reperfusion injury.. Experimental rats received inhibitors of p38, c-jun kinase, or extracellular signal-regulated kinase before in situ left lung ischemia-reperfusion. Immunohistochemistry localized cellular sites of mitogen-activated protein kinase activation. Several markers of lung injury were assessed. Enzyme-linked immunosorbent assay measured soluble cytokine and chemokine contents. Western blotting assessed mitogen-activated protein kinase phosphorylation. Electromobility shift assays measured transcription factor nuclear translocation.. Immunohistochemistry localized p38 and c-jun kinase activations in positive controls to alveolar macrophages. Extracellular signal-regulated kinase was activated in endothelial and epithelial cells. Animals treated with p38 or c-jun kinase inhibitor demonstrated significant reductions in transcription factor activation and markers of lung injury. Extracellular signal-regulated kinase inhibition was not protective. Western blotting confirmed inhibitor specificity.. Inhibition of p38 and c-jun kinase provided significant protection from injury. The alveolar macrophage appears to be the key coordinator of injury in response to oxidative stress. Therapeutically targeting specific cell population (macrophage) responses to oxidative stress has the potential benefit of reducing lung reperfusion injury severity while leaving host immune responses intact.

Topics: Animals; Anthracenes; Blotting, Western; Bronchoalveolar Lavage Fluid; Butadienes; Disease Models, Animal; Enzyme Inhibitors; Enzyme-Linked Immunosorbent Assay; Female; Immunohistochemistry; Inflammation Mediators; Lung Diseases; Male; Mitogen-Activated Protein Kinases; Nitriles; Oxidative Stress; Peroxidase; Phosphorylation; Probability; Random Allocation; Rats; Rats, Sprague-Dawley; Reference Values; Reperfusion Injury; Sensitivity and Specificity

To investigate the mechanism of the injury of intestinal mucosal induced by intestinal ischemia-reperfusion and the protect effects of Urinary Trypsin Inhibitor (UTI).. Thirty male Wistar rats were randomly divided into three groups, the sham operation group (SO), ischemia 45 minutes and reperfusion 6 hours group (I/R), UTI-treated group (UTI). Using clamping and then releasing the superior mesenteric artery the model of intestinal ischemia-reperfusion in rats was made. UTI group was given UTI 2 x 10(4) U/KG by administering intravenously before 30 minutes of operation, while the group SO and I/R were intravenously injected with saline. Blood, intestinal tissue and lymph node were obtained after 6 hours of reperfusion. The level of intestinal fatty acid binding protein (IFABP), Tumor Necrosis Factor-alpha (TNF-alpha), Nitric Oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD), myeloperoxidase (MPO) and the rate of bacterial translocation (BT) in each group were examined. Intestinal tissue samples were also taken for histological analysis by light microscopy and electron microscopy.. The content of IFABP, TNF-alpha, NO, MDA and MPO were significantly lower in group UTI than in group I/R [IFABP (520.87 +/- 75.41) pg/ml vs (493.57 +/- 136.35) pg/ml, NO (58.97 +/- 7.06) micromol/L vs (95.15 +/- 9.13) micromol/L, TNF-alpha (15.38 +/- 1.70) pg/ml to (23.55 +/- 4.34) pg/ml, MDA (4.5 +/- 1.1) nmol/mg vs (9.2 +/- 2.6) nmol/mg, MPO (1.98 +/- 0.22) U/g vs (3.02 +/- 0.55) U/g, SOD (77.08 +/- 7.14) U/mg vs (60.61 +/- 6.83) U/mg, P < 0.01]. There was significant difference in the rate of lymph node BT between the group UTI and I/R (P < 0.05). Histological changes showed that milder damage of intestinal mucosal in group UTI as to group I/R.. Intestinal ischemia-reperfusion may result in intestinal mucosal damage, the mechanism may be involved in the release of abnormal TNF-alpha, NO, reactive oxygen and activated PMN; UTI can protect intestinal mucosal against intestinal ischemia-reperfusion injury, which may be associated with inhibiting the release of NO and TNF-a, ameliorating reactive oxygen damage, decreasing the aggregation and activation of PMN.

Topics: Animals; Bacterial Translocation; Glycoproteins; Intestinal Mucosa; Intestines; Ischemia; Ischemic Preconditioning; Male; Malondialdehyde; Nitric Oxide; Peroxidase; Random Allocation; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase; Trypsin Inhibitors

Orexins are involved in the regulation of sleeping behavior and energy homeostasis, and they are also implicated in the regulation of gastrointestinal functions. Previous reports have demonstrated the expression of orexin receptors in the gastrointestinal system. The aim of this study was to investigate the gastroprotective effect of orexin-A in ischemia-reperfusion-induced gastric mucosal injury.. The gastric ischemia-reperfusion model was established by clamping the celiac artery for 30 min and reperfusing for 60 min. Orexin-A was administered in doses of 500 pmol.kg(-1).min(-1) by infusion throughout the ischemia-reperfusion period. The mean lesion area, gastric prostaglandin E2 and mucus content, myeloperoxidase activity, and production of thiobarbituric acid reactive substances were measured.. Orexin-A significantly attenuated the ischemia-reperfusion-induced gastric lesions and also decreased myeloperoxidase activity and the thiobarbituric acid reactive substances content in gastric mucosa of rats exposed to ischemia-reperfusion. However, the decline in gastric prostaglandin E2 and mucus content was not restored by orexin-A treatment.. Orexin-A exhibited a gastroprotective effect against ischemia-reperfusion-induced lesions by decreasing neutrophil activation and lipid peroxidation.

Topics: Animals; Dinoprostone; Female; Gastric Mucosa; Intracellular Signaling Peptides and Proteins; Lipid Peroxidation; Mucus; Neuropeptides; Neurotransmitter Agents; Neutrophil Activation; Orexins; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Thiobarbituric Acid Reactive Substances

Various mechanisms have been proposed for the pathogenesis of postischemic hepatic injury, including the generation of reactive oxygen metabolites. Oxytocin (OT) possesses antisecretory, antiulcer effects, facilitates wound healing and has anti-inflammatory properties. Hepatic ischemia-reperfusion (I/R)-injury was induced by inflow occlusion to median and left liver lobes ( approximately 70%) for 30 min of ischemia followed by 1h reperfusion in female Sprague-Dawley rats under anesthesia. I/R group (n=8) was administered intraperitoneally either OT (500 microg/kg) or saline at 24 and 12 h before I/R and immediately before reperfusion. Sham-operated group that underwent laparotomy without hepatic ischemia served as the control. Rats were decapitated at the end of reperfusion period. Hepatic samples were obtained for the measurement of myeloperoxidase (MPO) activity, malondialdehyde (MDA), glutathione (GSH) and collagen levels and histopathological analysis. Tumor necrosis factor-alfa (TNF-alpha) and transaminases (SGOT, SGPT) were assayed in serum samples. I/R injury caused significant increases in hepatic microscopic damage scores, MPO activity, collagen levels, transaminase, serum TNF-alpha levels. Oxytocin treatment significantly reversed the I/R-induced elevations in serum transaminase and TNF-alpha levels and in hepatic MPO and collagen levels, and reduced the hepatic damage scores. OT treatment had tendency to abolish I/R-induced increase in MDA levels, while GSH levels were not altered. These results suggest that OT has a protective role in hepatic I/R injury and its protective effect in the liver appears to be dependent on its inhibitory effect on neutrophil infiltration.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Collagen; Female; Fibrosis; Glutathione; Liver; Malondialdehyde; Neutrophil Infiltration; Oxytocin; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

Gut ischemia/reperfusion (I/R) injury is a serious condition in intensive care patients. Activation of immune cells adjacent to the huge endothelial cell surface area of the intestinal microvasculature produces initially local and then systemic inflammatory responses. Stimulation of the vagus nerve can rapidly attenuate systemic inflammatory responses through inhibiting the activation of macrophages and endothelial cells. Ghrelin, a novel orexigenic hormone, is produced predominately in the gastrointestinal system. Ghrelin receptors are expressed at a high density in the dorsal vagal complex of the brain stem. In this study, we investigated the regulation of the cholinergic anti-inflammatory pathway by the novel gastrointestinal hormone, ghrelin, after gut I/R.. Gut ischemia was induced by placing a microvascular clip across the superior mesenteric artery for 90 min in male adult rats. Our results showed that ghrelin levels were significantly reduced after gut I/R and that ghrelin administration inhibited pro-inflammatory cytokine release, reduced neutrophil infiltration, ameliorated intestinal barrier dysfunction, attenuated organ injury, and improved survival after gut I/R. Administration of a specific ghrelin receptor antagonist worsened gut I/R-induced organ injury and mortality. To determine whether ghrelin's beneficial effects after gut I/R require the intact vagus nerve, vagotomy was performed in sham and gut I/R animals immediately prior to the induction of gut ischemia. Our result showed that vagotomy completely eliminated ghrelin's beneficial effect after gut I/R. To further confirm that ghrelin's beneficial effects after gut I/R are mediated through the central nervous system, intracerebroventricular administration of ghrelin was performed at the beginning of reperfusion after 90-min gut ischemia. Our result showed that intracerebroventricular injection of ghrelin also protected the rats from gut I/R injury.. These findings suggest that ghrelin attenuates excessive inflammation and reduces organ injury after gut I/R through activation of the cholinergic anti-inflammatory pathway.

Topics: Animals; Ghrelin; Inflammation; Injections, Intraventricular; Interleukin-6; Intestinal Mucosa; Intestines; Lactic Acid; Lung; Male; Organ Specificity; Permeability; Peroxidase; Protective Agents; Rats; Rats, Sprague-Dawley; Receptors, Ghrelin; Reperfusion Injury; Survival Rate; Tumor Necrosis Factor-alpha; Vagotomy; Vagus Nerve

Intestinal ischemia/reperfusion (I/R) injury has been shown to cause intestinal mucosal injury and adversely affect function. Ischemic preconditioning (IPC) has been shown to protect against intestinal I/R injury by reducing polymorphonuclear leukocyte infiltration, intestinal mucosal injury, and liver injury, and preserve intestinal transit. Bone morphogenetic protein 7 (BMP-7) has been shown to protect against I/R injury in the kidney and brain. Recently, microarray analysis has been used to examine the possible IPC candidate pathways. This work revealed that IPC may work through upregulation of BMP-7. The purpose of this study was to examine if pretreatment with BMP-7 would replicate the effects seen with IPC in the intestine and liver after intestinal I/R. Rats were randomized to six groups: sham, I/R (30 min of superior mesenteric artery occlusion and 6 h of R), IPC+R (three cycles of superior mesenteric artery occlusion for 4 min and R for 10 min), IPC+I/R, BMP-7+R (100 microm/kg recombinant human BMP-7), or BMP-7+I/R. A duodenal catheter was placed, and 30 min before sacrifice, fluorescein isothiocyanate-Dextran was injected. At sacrifice, dye concentrations were measured to determine intestinal transit. Ileal mucosal injury was determined by histology and myeloperoxidase activity was used as a marker of polymorphonuclear leukocyte infiltration. Serum levels of aspartate aminotransferase were measured at sacrifice to determine liver injury. Pretreatment with BMP-7 significantly improved intestinal transit and significantly decreased intestinal mucosal injury and serum aspartate aminotransferase levels, comparable to animals undergoing IPC. In conclusion, BMP-7 protected against intestinal I/R-induced intestinal and liver injury. Bone morphogenetic protein 7 may be a more logical surrogate to IPC in the prevention of injury in the setting of intestinal I/R.

Topics: Animals; Bone Morphogenetic Protein 7; Gastrointestinal Transit; Intestinal Mucosa; Intestines; Ischemic Preconditioning; Liver; Male; Peroxidase; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Activated protein C (APC) is a serine protease with anticoagulant and antiinflammatory activities. The delaying effects of remote reperfusion injury on the wound-healing process in colonic anastomoses have been previously shown. In this study, we aimed to investigate whether APC protects against deleterious systemic effects of intestinal ischemia/reperfusion (I/R) injury on colonic anastomotic wound healing process.. Male Wistar-albino rats were randomly allocated into 4 groups, and a left colonic anastomosis was performed in all animals: (1) sham-operated group, simultaneously with left colonic anastomosis, the superior mesenteric artery and collateral branches were divided from the celiac axis, and the inferior mesenteric artery were isolated but not occluded (group 1, n = 12), (2) sham + APC group, identical to group 1 except for APC treatment (100 microg/kg, intravenously, 15 minutes before construction of the colonic anastomosis), (group 2, n = 12), (3) intestinal I/R group, 60 minutes of superior mesenteric ischemia followed by reperfusion (group 3, n = 12), and (4) APC-treated group, (100 microg/kg, intravenously, 15 minutes before reperfusion) (group 4, n = 12). All animals were sacrificed, and colonic anastomotic bursting pressures were measured in vivo on day 7. Tissue samples were obtained for analysis of hydroxyproline contents, nitrate/nitrite levels, and activities of oxidative and antioxidative enzymes. The plasma levels of proinflammatory cytokines and D-dimer were also measured.. Intestinal I/R led to significant decreases in colonic anastomotic bursting pressures, tissue hydroxyproline contents, and activities of antioxidative enzymes, along with increases in tissue nitrate/nitrite levels, activities of oxidative enzymes, and plasma levels of proinflammatory cytokines and D-dimer (P < .05). However, APC treatment led to significant increases in colonic anastomotic bursting pressures, tissue hydroxyproline contents, and activities of antioxidative enzymes, along with decreases in tissue nitrate/nitrite levels, activities of oxidative enzymes, and plasma levels of proinflammatory cytokines and D-dimer (P < .05).. This study clearly showed that APC treatment prevented the delaying effects of remote I/R injury on colonic anastomotic wound healing process. Further clinical studies are required to determine whether APC has a useful role in the enhancement of colonic anastomotic wound healing after particular operations in which I/R injury occurs.

Topics: Analysis of Variance; Anastomosis, Surgical; Animals; Chi-Square Distribution; Glutathione; Glutathione Reductase; Interleukin-6; Intestines; Ischemia; Male; Malondialdehyde; Mesenteric Arteries; Mice; Nitrates; Nitrites; Peroxidase; Protein C; Random Allocation; Reperfusion Injury; Tumor Necrosis Factor-alpha; Wound Healing; Xanthine Oxidase

To study the protective effect of sodium pyruvate on ischemia/reperfusion injury following hemorrhagic shock.. Rat models of hemorrhagic shock were built up. When the shed blood was infused, the rats were also randomly provided by one of normal saline, glutathione and sodium pyruvate. Rats were killed 3 hours after the reperfusion, the activity of plasma lactate dehydrogenase (LDH) and glutamic-oxaloacetic transaminase (GOT), the level of tissue malondialdehyde (MDA) and the activity of tissue myeloperoxidase (MPO) were detected. Biopsy specimens were obtained to investigate morphological changes of the myocardial, hepatic, lung and renal tissue.. The activity of plasma LDH and GOT, the level of MDA of hepatic, lung and renal tissue and the activity of MPO of myocardial, lung and renal tissue decreased remarkably in group given sodium pyruvate compared with group given normal saline, and the effect of group given sodium pyruvate was more remarkable than group given glutathione.. These data support the view that sodium pyruvate shows protective effect on ischemia/reperfusion injury following hemorrhagic shock. It is possibly relevant to scavenging of oxygen free radicals, reduction of neutrophil, and anti-inflammatory response.

Topics: Animals; Aspartate Aminotransferases; Disease Models, Animal; Kidney; L-Lactate Dehydrogenase; Liver; Lung; Male; Malondialdehyde; Peroxidase; Protective Agents; Pyruvic Acid; Rats; Rats, Wistar; Reperfusion Injury; Shock, Hemorrhagic

Phospholipase A2s (PLA2s) seem to be involved in the pathophysiology of ischemic brain injury, but their specific role is far from being completely understood. The present study was carried out to ascertain how and to what extent secretory PLA2s (sPLA2s) activity influences outcome after cerebral ischemia-reperfusion, and to correlate this with the inflammatory response. To do this we used the potent and selective sPLA2 inhibitor, 12-epi-scalaradial. Male Wistar rats were separated into three groups: a control group receiving intracerebroventricular vehicle, and two groups receiving intracerebroventricular 0.005 or 0.5 microg/h 12-epi-scalaradial. Every animal was subjected to middle cerebral artery (MCA) occlusion (90 min, intraluminal thread technique) under continuous moni-torization of cerebrocortical perfusion (CP, laser-Doppler flowmetry), followed by reperfusion (3 days). Neurological status, infarct volume, and myeloperoxidase (MPO) activity were the main end points. Three days after the 90-min ischemia period, neurological examination did not reveal significant differences between the three groups of rats. Control rats showed a mean infarct volume of 145.9 +/- 24.7 mm3 (21 +/- 4.1% of the ipsilateral hemisphere volume), while mean infarct volume in rats treated with 0.005 or 0.5 microg/h 12-epi-scalaradial increased to 164.8 +/- 86.8 mm3 (22.0 +/- 10.9%) and 211.5 +/- 12.2 mm3 (28 +/- 3%, P < 0.05), respectively. Treatment with the highest dose of 12-epi-scalaradial (0.5 microg/h) increased MPO activity in the ipsilateral hemisphere by about 140% (from 0.59 +/- 0.59 to 1.42 +/- 1.03 units of activity/g of tissue in comparison with the control ischemic hemisphere, P < 0.05). Overall, our results point to a positive rather than a negative influence of sPLA2 activity during ischemia. This, along with its inability to decrease the inflammatory response, does not allow to propose the use of 12-epi-scalardial as a potential drug for stroke therapy.

Topics: Animals; Cerebral Infarction; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Administration Routes; Drug Administration Schedule; Homosteroids; Infarction, Middle Cerebral Artery; Laser-Doppler Flowmetry; Male; Neurologic Examination; Neuroprotective Agents; Peroxidase; Phospholipases A2; Rats; Rats, Wistar; Reperfusion Injury; Sesterterpenes; Time Factors

Renal failure from ischemia contributes to morbidity and mortality. Ischemic preconditioning (IP) represents a powerful strategy for kidney protection, and recent advances in transgenic mice may help elucidate its molecular mechanisms. However, murine IP is technically challenging and experimental details significantly influence results. Thus we developed a novel model for renal IP using a hanging-weight system for isolated renal artery occlusion. In contrast to previous models, this technique eliminates the need for clamping the vascular pedicle (artery/vein). In fact, assessment of renal injury after different time periods of ischemia (10-60 min) revealed highly reproducible increases in plasma creatinine and potassium levels, while creatinine clearance, urinary flow and potassium/sodium excretion were significantly attenuated. Using different numbers of IP cycles, we found maximal protection with four cycles of 4 min of ischemia-reperfusion. In contrast, no significant renal protection was observed with IP of the vascular pedicle. To assess transcriptional responses in this model, we isolated RNA from preconditioned kidneys and found time-dependent induction of erythropoietin mRNA and plasma levels with IP. Taken together, this model provides highly reproducible renal injury and protection by IP, thus minimizing variability associated with previous techniques based on clamping of the renal pedicle. Further studies on renal ischemia/IP in mice may consider this technique.

Topics: Animals; Blood Pressure; Creatinine; DNA, Complementary; Gene Expression Regulation; Heart Rate; Immunohistochemistry; Ischemic Preconditioning; Kidney; Mice; Mice, Inbred C57BL; Peroxidase; Potassium; Renal Artery; Renal Circulation; Reperfusion Injury; RNA, Messenger

CXC chemokines, including human interleukin-8 and rat cytokine-induced neutrophil chemoattractant-1, play a crucial role in the pathogenesis of intestinal inflammation induced by ischemia-reperfusion (I-R). Thrombin and its specific receptor, protease-activated receptor 1 (PAR1), act as important players in inflammation. However, the association between thrombin activation and chemokine production during I-R has not been well studied. We investigated whether thrombin and PAR1 might be involved in the pathophysiology of intestinal I-R, using an in vivo model. Intestinal damage was induced by clamping the superior mesenteric artery for 30 min followed by reperfusion in male Wistar rats. Thrombin-antithrombin complex was measured as an indicator of thrombin activation. PAR1 expression in the intestine was evaluated by real-time PCR. The severity of the intestinal mucosal injury was evaluated on the distal segment of the ileum by several biochemical markers and histological findings. Reperfusion significantly increased the serum levels of thrombin-antithrombin complex and enhanced PAR1 expression in the intestinal mucosa. The levels of both intraluminal hemoglobin and protein were significantly increased in the I-R group. The mucosal myeloperoxidase activity and expressions and/or productions of cytokine-induced neutrophil chemoattractant-1 and TNF-alpha were significantly increased after I-R. These increases were inhibited by the treatment of rat with antithrombin intravenously before I-R at a dose of 30 U/kg. These results suggest that the thrombin/PAR1 pathway plays an important role in the production of these cytokines during I-R and that antithrombin exerts potent anti-inflammatory effects on this injury via inhibition of proinflammatory cytokines.

Topics: Animals; Antithrombin III; Antithrombins; Chemokine CXCL1; Chemokines, CXC; Gene Expression; Hemoglobins; Ileum; Intestinal Mucosa; Intestine, Small; Intestines; Male; Peptide Hydrolases; Peroxidase; Rats; Rats, Wistar; Receptor, PAR-1; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Signal Transduction; Thrombin; Tumor Necrosis Factor-alpha

Hepatic warm ischemia during surgery remains a significant problem, particularly in organs with possible baseline dysfunction. The objective of this study was to investigate whether age influences the degree of warm ischemia-reperfusion injury in rat livers.. The left and median lobes of young (3 months) and adult (9 months) male rats were exposed to 75 min of ischemia followed by reperfusion. Each age group was divided into two sub-groups. One sub-group was observed for 8 h, whereas the other was allowed to survive. Animals in the 8-h groups (young and adult) were sacrificed, and blood and tissue were taken to determine liver enzymes, neutrophil accumulation, and blood metabolic profiles and to examine the histology.. Hepatocellular injury was significantly greater in adult rats after 8 h of reperfusion, as determined by hepatic enzyme levels and histology. Liver enzyme levels were massively elevated in adult rats and were significantly higher compared with those of young rats. The degree of necrosis and neutrophil accumulation was significantly higher in adult rats. After 8 h of reperfusion, the metabolic profiling of the blood revealed elevated levels of creatine, creatinine, allantoin, and amino acids (tyrosine, methionine) in the adult rats. At 24 h of reperfusion, all adult rats died, in contrast to young rats, which all survived.. Aging in rats is associated with greater hepatocellular injury and poor survival rate after 75 min of warm hepatic ischemia.

Topics: Aging; Animals; Body Weight; Liver; Magnetic Resonance Spectroscopy; Male; Neutrophils; Organ Size; Peroxidase; Rats; Rats, Inbred Lew; Reperfusion Injury; Severity of Illness Index; Survival Rate; Temperature

Liver ischemia/reperfusion (I/R) results in the release of destructive proinflammatory cytokines and oxygen-derived radicals, which in turn cause injury to liver and other organs such as kidney, lung, and intestine. Splenectomy protects organs from intestinal I/R injury. Therefore, the present study aims to investigate whether splenectomy could also ameliorate multiple organ damage caused by liver I/R.. Wistar rats randomly assigned into 4 groups underwent sham-operation, splenectomy, hepatic I/R induced by occlusion of hepatic artery and portal vein, and splenectomy plus hepatic I/R, respectively. Blood samples were collected for assessing aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activity, and tumor necrosis factor-alpha (TNF-alpha) levels. The activity of myeloperoxidase (MPO) in liver tissues was assessed. Livers, kidneys, lungs, and small intestines underwent histopathologic examination for scoring injury severity and TUNEL assay for cell apoptosis. The expression of caspase-3 was evaluated with Western blot analysis.. Liver I/R resulted in liver injury as evidenced by morphologic abnormalities, increased serum activities of AST and ALT, and increased percentage of apoptotic cells. The activity of MPO in liver tissues and the serum levels of TNF-alpha were increased after I/R. Splenectomy significantly decreased the histologic severity score, apoptotic index, MPO activity, and serum levels of AST, ALT, and TNF-alpha. Hepatic I/R also caused damage to kidneys, lungs, and small intestines, as evaluated by histologic alterations and increased apoptotic cells; these changes were ameliorated by splenectomy. The expression of caspase-3 was upregulated in the 4 organs by hepatic I/R and inhibited by splenectomy.. Splenectomy protects the liver as well as the kidney, lung, and intestine from injury by hepatic I/R. Although the mechanism needs further investigation, this study demonstrated that splenectomy inhibited leukocyte infiltration in livers, release of TNF-alpha, cell apoptosis, and expression of caspase-3.

Topics: Alanine Transaminase; Animals; Apoptosis; Aspartate Aminotransferases; Caspase 3; Intestines; Kidney; Liver; Male; Multiple Organ Failure; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Splenectomy; Tumor Necrosis Factor-alpha

The preventive effect of Anemarrhena asphodeloides Bunge (Liliaceae), a traditional Chinese medicine, on ischemia-reperfusion-induced brain injury was evaluated in the rat brain. Ischemia was induced by intraluminal occlusion of the right middle cerebral artery for 2 h and reperfusion was continued for 22 h. Water extract of Anemarrhena asphodeloides (WEAA) was orally administered promptly prior to and 2 h after reperfusion. Total infarct volume and edema in the ipsilateral hemispheres of ischemia-reperfusion rats were significantly reduced by treatment with WEAA in a dose-dependent manner (p<0.05). The therapeutic time window of WEAA was 3 h in this ischemia-reperfusion rat model. WEAA also significantly inhibited increased neutrophil infiltration of ischemic brain tissue as estimated by myeloperoxidase (MPO) activity and immunohistochemical analysis. MPO-positive cells were markedly reduced by WEAA administration in striatal and cortical areas. These findings suggest that WEAA plays a crucial protective role in ischemia-induced brain injury, and suggest that WEAA could serve as a lead medicinal herb for the development of neuroprotective agents following transient focal ischemic brain injury.

Topics: Anemarrhena; Animals; Biphenyl Compounds; Brain; Disease Models, Animal; Dose-Response Relationship, Drug; Drugs, Chinese Herbal; Free Radical Scavengers; Hydrazines; Immunohistochemistry; Infarction, Middle Cerebral Artery; Ischemic Attack, Transient; Male; Neuroprotective Agents; Neutrophil Infiltration; Peroxidase; Picrates; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Rhizome; Saponins; Time Factors; Triterpenes

Experimental data suggest that transient preoperative ischemia and reperfusion may compromise anastomotic strength. However, data on this subject are equivocal, in particular as to the onset and duration of this effect. This study was designed to comprehensively characterize the effects of profound transient intestinal ischemia on anastomotic healing during the first postoperative week.. Ischemia was induced in rats by clamping both the superior mesenteric artery and ileal branches for 30 minutes. Immediately after declamping, anastomoses were constructed in both terminal ileum and descending colon. After three, five, or seven days, both bursting pressure and breaking strength were measured. Anastomotic collagen content, gelatinase activity, and histology were analyzed.. Anastomotic leakage rate was 13 percent in ischemia-reperfusion group and 0 percent (P=0.02) in controls. The breaking strength in ileum remained significantly (P<0.05) lower in the ischemic groups than in the control groups at all time points. Bursting pressure in the ileum was not significantly different between ischemic and control groups at either of the time points measured. However, at Day 7 the bursting site was significantly more frequent within the suture line in the ischemic groups. In the colon, at Day 3 the bursting pressure was 35 percent lower in the ischemic group than in the control group (P<0.05). Anastomotic collagen content and gelatinase activity were similar in ischemic and control groups.. Transient profound splanchnic ischemia compromises anastomotic strength throughout the entire first postoperative week. This effect does not seem to be caused by impaired accumulation of wound collagen.

Topics: Anastomosis, Surgical; Animals; Colon; Disease Models, Animal; Follow-Up Studies; Gelatinases; Hydroxyproline; Ileum; Male; Mesentery; Peroxidase; Pressure; Rats; Rats, Wistar; Reperfusion Injury; Treatment Outcome

Ischemia/reperfusion injury is regarded as the main cause of failure in revascularization of limbs and transfer of free flaps in the so called nonreflow phenomenon. This type of damage is caused by the production of free radicals, above all, of neutrophils that release great quantities of extracellular superoxide through the action of a membrane enzyme. In our study we used 40 white rabbits. Rabbit rectus femoris muscle is perfused by a single artery and vein and is therefore a valuable model for study of ischemia-induced reperfusion injury of skeletal muscle. The objective of this study was to individualize a valid method of protection for the muscle from damage by ischemia-induced reperfusion injury. We have tested the effectiveness of WEB2170, a PAF antagonist, of hyperbaric oxygen therapy one (HBO), and of combined employment of WEB2170 and HBO. The results show that both PAF and HBO play important protective roles against damage from ischemia/reperfusion injury, and that the combined employment of both therapies has a synergistic effect. We propose therefore a new therapeutic protocol for the prevention of damage resulting from ischemia/reperfusion injury with the simultaneous employment of this PAF and HBO.

Topics: Animals; Azepines; Combined Modality Therapy; Disease Models, Animal; Hyperbaric Oxygenation; Muscle, Skeletal; Peroxidase; Platelet Aggregation Inhibitors; Rabbits; Reperfusion Injury; Triazoles

The nuclear enzyme poly(ADP-ribose) polymerase (PARP) is activated by oxidative stress and plays a significant role in postischemic brain injury. We assessed the contribution of PARP activation to the blood-brain barrier (BBB) disruption and edema formation after ischemia-reperfusion. In male Wistar rats, global cerebral ischemia was achieved by occluding the carotid arteries and lowering arterial blood pressure for 20 mins. The animals were treated with saline or with the PARP inhibitor N-(6-oxo-5,6-dihydrophenanthridin-2-yl)-N, N-dimethylacetamide.HCl (PJ34); (10 mg/kg, i.v.) before ischemia. After 40 mins, 24, and 48 h of reperfusion, the permeability of the cortical BBB was determined after Evans Blue (EB) and Na-fluorescein (NaF) administration. The water content of the brain was also measured. The permeability of the BBB for EB increased after ischemia-reperfusion compared with the nonischemic animals after 24 and 48 h reperfusion but PARP inhibition attenuated this increase at 48 h (nonischemic: 170+/-9, saline: 760+/-95, PJ34: 472+/-61 ng/mg tissue). The extravasation of NaF showed similar changes and PJ34 post-treatment attenuated the permeability increase even at 24 h. PARP inhibition decreased the brain edema seen at 48 h. Because PARP has proinflammatory properties, the neutrophil infiltration of the cortex was determined, which showed lower values after PJ34 treatment. Furthermore, PJ34 treatment decreased the loss of the tight junction protein occludin at 24 and 48 h. The inhibition of PARP activity accompanied by reduced post-ischemic BBB disturbance and decreased edema formation suggests a significant role of this enzyme in the development of cerebral vascular malfunction

Topics: Animals; Blood-Brain Barrier; Blotting, Western; Brain; Brain Edema; Capillary Permeability; Enzyme Activation; Hypoxia-Ischemia, Brain; Intercellular Adhesion Molecule-1; Male; Membrane Proteins; Occludin; Peroxidase; Phenanthrenes; Poly(ADP-ribose) Polymerases; Rats; Rats, Wistar; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction

The purpose of this study was to examine the effects of simvastatin pretreatment in the setting of acute limb ischemia-reperfusion injury in an experimental diabetes model that is associated with a high risk for limb loss.. Adult male Sprague-Dawley rats were randomized into two groups. Diabetes was induced in the first group by intravenous streptozotocin injection. The second group served as the nondiabetic group. Eight weeks after the streptozotocin injection, half of the rats in the diabetic and the nondiabetic groups were further randomized to receive either intraperitoneal simvastatin (1 mg/kg per day) or saline treatment for 6 weeks. Bilateral hind-limb ischemia was induced for 4 hours by the tourniquet method. After 24 hours of reperfusion, tissue samples were collected from the gastrocnemius and anterior tibial muscles bilaterally for measurement of muscle edema, percentage of necrosis, and malondialdehyde (MDA), glutathione, and myeloperoxidase (MPO) levels.. Ischemic injury was more prominent in diabetic animals. The diabetic animals with limb ischemia exhibited a 7% increase in tissue edema, a 47% increase in muscle necrosis and MPO level, and a 15% reduction in glutathione levels compared with the nondiabetic animals (P < .05). Simvastatin treatment with 1 mg/kg for 6 weeks reduced the ischemic injury. Simvastatin pretreatment led to a 71% reduction in muscle necrosis in diabetic animals (P < .001). The protective effects of simvastatin pretreatment also correlated with a 23% improvement in tissue edema, a 75% reduction in tissue myeloperoxidase content, and a 71% increase in glutathione levels in diabetic animals (P < .01). Furthermore, skeletal muscle injury, characterized by tissue edema and leucosequestration, was significantly less severe with simvastatin pretreatment compared with the nondiabetic animals (P < .01).. Simvastatin pretreatment reduced limb ischemia-reperfusion injury in diabetic and nondiabetic animals. We conclude that simvastatin pretreatment may be a potential therapeutic intervention for skeletal muscle ischemia-reperfusion injury in the clinical setting.

Topics: Animals; Diabetes Mellitus, Experimental; Edema; Glutathione; Hindlimb; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Ischemia; Male; Malondialdehyde; Muscle, Skeletal; Necrosis; Peroxidase; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Severity of Illness Index; Simvastatin; Time Factors; Tourniquets

To evaluate the protective effect of alpha-lipoic acid in reducing oxidative damage after severe hepatic ischemia/reperfusion (IR) injury.. Wistar albino rats were subjected to 45 min of hepatic ischemia, followed by 60 min reperfusion period. Lipoic acid (100 mg/kg i.p.) was administered 15 min prior to ischemia and immediately before reperfusion period. At the end of the reperfusion period aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH) activity, and cytokine, TNF-alpha and IL-1beta levels were determined in serum samples. Malondialdehyde (MDA), and glutathione (GSH) levels and myeloperoxidase (MPO) activity were determined in the liver tissue samples while formation of reactive oxygen species was monitored by using chemiluminescence (CL) technique with luminol and lucigenin probes. Tissues were also analyzed histologically.. Serum ALT, AST, and LDH activities and TNF-alpha and IL-1beta levels were elevated in the I/R group, while this increase was significantly lower in the group of animals treated concomitantly with lipoic acid. Hepatic GSH levels, significantly depressed by I/R, were elevated back to control levels in lipoic acid-treated I/R group. Furthermore, increases in tissue luminol and lucigenin CL, MDA levels and MPO activity due to I/R injury were reduced back to control levels with lipoic acid treatment.. Since lipoic acid administration alleviated the I/R-induced liver injury and improved the hepatic structure and function, it seems likely that lipoic acid with its antioxidant and oxidant-scavenging properties may be of potential therapeutic value in protecting the liver against oxidative injury due to ischemia-reperfusion.

Topics: Acridines; Alanine Transaminase; Animals; Antioxidants; Aspartate Aminotransferases; Glutathione; Hepatocytes; Interleukin-1beta; L-Lactate Dehydrogenase; Lipid Peroxidation; Liver; Luminol; Male; Malondialdehyde; Microscopy, Polarization; Neutrophil Infiltration; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Thioctic Acid; Tumor Necrosis Factor-alpha

Oxytocin was previously shown to have anti-inflammatory effects in different inflammation models. The major objective of the present study was to evaluate the protective role of oxytocin (OT) in protecting the kidney against ischemia/reperfusion (I/R) injury.. Male Wistar albino rats (250-300 g) were unilaterally nephrectomized, and subjected to 45 min of renal pedicle occlusion followed by 6 h of reperfusion. OT (1 mg/kg, ip) or vehicle was administered 15 min prior to ischemia and was repeated immediately before the reperfusion period. At the end of the reperfusion period, rats were decapitated and kidney samples were taken for histological examination or determination of malondialdehyde (MDA), an end product of lipid peroxidation; glutathione (GSH), a key antioxidant; and myeloperoxidase (MPO) activity, an index of tissue neutrophil infiltration. Creatinine and urea concentrations in blood were measured for the evaluation of renal function, while TNF-alpha and lactate dehydrogenase (LDH) levels were determined to evaluate generalized tissue damage. Formation of reactive oxygen species in renal tissue samples was monitored by chemiluminescence technique using luminol and lucigenin probes.. The results revealed that I/R injury increased (p<0.01-0.001) serum urea, creatinine, TNF-alpha and LDH levels, as well as MDA, MPO and reactive oxygen radical levels in the renal tissue, while decreasing renal GSH content. However, alterations in these biochemical and histopathological indices due to I/R injury were attenuated by OT treatment (p<0.05-0.001).. Since OT administration improved renal function and microscopic damage, along with the alleviation of oxidant tissue responses, it appears that oxytocin protects renal tissue against I/R-induced oxidative damage.

Topics: Animals; Creatinine; Disease Models, Animal; Glutathione; Kidney; Kidney Diseases; L-Lactate Dehydrogenase; Male; Malondialdehyde; Oxytocin; Peroxidase; Protective Agents; Rats; Rats, Wistar; Reactive Oxygen Species; Reperfusion Injury; Tumor Necrosis Factor-alpha; Urea

Microcirculatory dysfunctions and mast cell (MC) reactions play important roles in hypoxic tissue injuries. The aims of this study were to characterize the effects of hindlimb ischemia-reperfusion (I-R) on the periosteal microcirculation and to define the consequences of systemic phosphatidylcholine (PC) therapy during this condition.. Microcirculatory changes were visualized by means of fluorescence intravital videomicroscopy in anesthetized Wistar rats. There was 60 min of complete hindlimb ischemia followed by a 180-min reperfusion in the presence of PC treatment (50 mg/kg i.v.; in the second 10 min of reperfusion) or vehicle. Further two groups served as vehicle- or PC-treated sham-operated controls. The proportion of degranulated MCs and the leukocyte accumulation (myeloperoxidase, MPO assay) were determined in muscle biopsies.. I-R significantly increased the muscle MPO activity (from 14.94 to 63.45 mU/mg) and the proportion of degranulated MCs (to 82.5%). The periosteal capillary RBC velocity (RBCV) and the functional capillary density (FCD) had decreased, while the primary and secondary leukocyte-endothelial cell interactions had increased by the end of reperfusion (rolling from 20.8 to 40.0%, and firm adherence from 254 to 872 mm(-2)). PC treatment decreased the leukocyte rolling and sticking, preserved the FCD and improved the RBCV. The MC degranulation and MPO activity diminished significantly in the muscle layer.. PC administration improves I-R-induced periosteal microcirculatory dysfunctions and ameliorates secondary inflammatory reactions. Systemic PC treatment could offer a potential treatment modality during hypoperfusion or inflammatory conditions of the bones.

Topics: Animals; Cell Degranulation; Hindlimb; Inflammation; Male; Mast Cells; Microcirculation; Peroxidase; Phosphatidylcholines; Rats; Rats, Wistar; Reperfusion Injury

To examine the effects of adenosine and A1 receptor activation on reperfusion-induced small intestinal injury.. Rats were randomized into groups with sham operation, ischemia and reperfusion, and systemic treatments with either adenosine or 2-chloro-N(6)-cyclopentyladenosine, A1 receptor agonist or 8-cyclopentyl-1,3-dipropylxanthine, A1 receptor antagonist, plus adenosine before ischemia. Following reperfusion, contractions of ileum segments in response to KCl, carbachol and substance P were recorded. Tissue myeloperoxidase, malondialdehyde, and reduced glutathione levels were measured.. Ischemia significantly decreased both contraction and reduced glutathione level which were ameliorated by adenosine and agonist administration. Treatment also decreased neutrophil infiltration and membrane lipid peroxidation. Beneficial effects of adenosine were abolished by pretreatment with A1 receptor antagonist.. The data suggest that adenosine and A1 receptor stimulation attenuate ischemic intestinal injury via decreasing oxidative stress, lowering neutrophil infiltration, and increasing reduced glutathione content.

Topics: Adenosine; Adenosine A1 Receptor Agonists; Animals; Glutathione; Ileum; Intestines; Male; Muscle Contraction; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Thiobarbituric Acid Reactive Substances; Xanthines

To investigate the protective effects and possible mechanisms of Veratrum nigrum L.var. ussuriense Nakai alkaloids (VnA) on hepatic ischemia/reperfusion (I/R) injury in rats.. Forty male Wistar rats were randomly divided into four experimental groups (n = 10 in each): (A) Control group (the sham operation group); (B) I/R group (pretreated with normal saline); (C) Small-dose (10 microg/kg) VnA pretreatment group; (D) Large-dose (20 microg/kg) VnA pretreatment group. Hepatic ischemia/reperfusion (Hepatic I/R) was induced by occlusion of the portal vein and the hepatic artery for 90 min, followed by reperfusion for 240 min. The pretreatment groups were administered with VnA intraperitoneally, 30 min before surgery, while the control group and I/R group were given equal volumes of normal saline. Superoxide dismutase (SOD) activity, myeloperoxidase (MPO) activity and nitric oxide (NO) content in the liver tissue at the end of reperfusion were determined and liver function was measured. The expression of intercellular adhesion molecule-1 (ICAM-1) and E-selectin (ES) were detected by immunohistochemical examinations and Western blot analyses.. The results showed that hepatic I/R elicited a significant increase in the plasma levels of alanine aminotransferase (ALT: 74.53 +/- 2.58 IU/L vs 1512.54 +/- 200.76 IU/L, P < 0.01) and lactic dehydrogenase (LDH: 473.48 +/- 52.17 IU/L vs 5821.53 +/- 163.69 IU/L, P < 0.01), as well as the levels of MPO (1.97 +/- 0.11 U/g vs 2.57 +/- 0.13 U/g, P < 0.01) and NO (69.37 +/- 1.52 micromol/g protein vs 78.39 +/- 2.28 micromol/g protein, P < 0.01) in the liver tissue, all of which were reduced by pretreatment with VnA, respectively (ALT: 1512.54 +/- 200.76 IU/L vs 977.93 +/- 89.62 IU/L, 909.81 +/- 132.76 IU/L, P < 0.01, P < 0.01; LDH: 5821.53 +/- 163.69 IU/L vs 3015.44 +/- 253.01 IU/L, 2448.75 +/- 169.4 IU/L, P < 0.01, P < 0.01; MPO: 2.57 +/- 0.13 U/g vs 2.13 +/- 0.13 U/g, 2.07 +/- 0.05 U/g, P < 0.01, P < 0.01; NO: 78.39 +/- 2.28 micromol/g protein vs 71.11 +/- 1.73 micromol/g protein, 68.58 +/- 1.95 micromol/g protein, P < 0.05, P < 0.01). The activity of SOD (361.75 +/- 16.22 U/mg protein vs 263.19 +/- 12.10 U/mg protein, P < 0.01) in the liver tissue was decreased after I/R, which was enhanced by VnA pretreatment (263.19 +/- 12.10 U/mg protein vs 299.40 +/- 10.80 U/mg protein, 302.09 +/- 14.80 U/mg protein, P < 0.05, P < 0.05). Simultaneously, the histological evidence of liver hemorrhage, polymorphonuclear neutrophil infiltration and the overexpression of ICAM-1 and E-selectin in the liver tissue were observed, all of which were attenuated in the VnA pretreated groups.. The results demonstrate that VnA pretreatment exerts significant protection against hepatic I/R injury in rats. The protective effects are possibly associated with enhancement of antioxidant capacity, reduction of inflammatory responses and suppressed expression of ICAM-1 and E-selectin.

Topics: Alanine Transaminase; Animals; Blotting, Western; E-Selectin; Immunohistochemistry; Intercellular Adhesion Molecule-1; L-Lactate Dehydrogenase; Liver; Male; Nitric Oxide; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase; Veratrum Alkaloids

Neutrophil activation to release granules containing proteases and other enzymes is a primary cause of tissue damage during ischemia/reperfusion injury. Because the contribution of specific granule enzymes to this injury remains poorly defined, the role of cathepsin G in renal ischemia/reperfusion injury was tested. Bilateral renal ischemia led to the expiration of 64% of wild-type mice within 4 days of reperfusion, whereas all cathepsin G-deficient mice survived. Serum creatinine increased to similar levels at 24 hours after reperfusion and then decreased to background in both groups of mice. Ischemic kidneys from both groups had similar levels of neutrophil infiltration and of CXCL1, CXCL2, and myeloperoxidase protein 9 hours after reperfusion, but at 24 hours, these acute inflammatory response components were decreased more than 50% in kidneys from cathepsin G-deficient versus wild-type mice. Ischemic kidneys from surviving wild-type mice had severe tubular necrosis and tubular cell apoptosis 24 hours after reperfusion with subsequent development of fibrosis 30 days later. In contrast, ischemic kidneys from cathepsin G-deficient mice had a 70% decrease in tubular cell apoptosis with little detectable collagen deposition. These data identify cathepsin G as a critical component sustaining neutrophil-mediated acute tissue pathology and subsequent fibrosis after renal ischemia/reperfusion injury.

Topics: Animals; Apoptosis; Cathepsin G; Cathepsins; Chemokine CXCL1; Chemokines, CXC; Creatinine; Enzyme-Linked Immunosorbent Assay; Fibrosis; In Situ Nick-End Labeling; Inflammation; Kidney; Mice; Neutrophil Infiltration; Peroxidase; Reperfusion Injury; Serine Endopeptidases

Aortic ischemia and reperfusion periods, which are often associated with infrarenal abdominal aortic cross-clamping and declamping, cause injury in distant organs including the heart. We recently reported that Kupffer cell blockage with gadolinium chloride (GdCl3) attenuates lung injury induced by aortic ischemia-reperfusion (IR). Therefore, we hypothesized that GdCl3 may attenuate myocardial injury induced by aortic IR.. The study was carried out in June 2005, in the Laboratory of Experimental Studies of Suleyman Demirel University Medical School, Isparta, Turkey. We studied the effect of GdCl3 on myocardial injury induced by abdominal aortic occlusion-reperfusion in rats by measuring the tissue levels of superoxide dismutase, catalase, malondialdehyde and activity of myeloperoxidase in rat heart specimens. Wistar-Albino rats (8 per group) were randomized into 3 groups. The control group underwent midline laparotomy and dissection of the infrarenal abdominal aorta without occlusion; the aortic IR group underwent laparotomy and clamping of the infrarenal abdominal aorta for 30 minutes followed by 60 minutes of reperfusion; and the GdCl3 + aortic IR group was pretreated with intravenous GdCl3 10 mg/kg 24 hours before the aortic IR.. Aortic IR significantly increased whereas pretreatment with GdCl3 significantly decreased oxygen free radical production, lipid peroxidation and neutrophil activation in the heart tissues of the rats.. Our results indicate that Kupffer cell blockage with GdCl3 attenuates the myocardial injury induced by aortic IR. We think that the novel findings of the present study may be a basis for further studies investigating the role of GdCl3 pretreatment in reducing myocardial morbidity and mortality caused by aortic IR during aortic surgery.

Topics: Animals; Arterial Occlusive Diseases; Biomarkers; Cardiotonic Agents; Disease Models, Animal; Female; Gadolinium; Kupffer Cells; Lipid Peroxidation; Male; Malondialdehyde; Myocardial Ischemia; Peroxidase; Probability; Random Allocation; Rats; Rats, Wistar; Reference Values; Reperfusion Injury; Sensitivity and Specificity; Superoxide Dismutase

Growing number of studies implicate that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, or statins, have beneficial effects on ischemia/reperfusion injury that are unrelated to their cholesterol-lowering action. In the present study, we aimed to evaluate possible effects of atorvastatin on oxidative stress, neutrophil accumulation, and contractile response of terminal ileum segments in rats subjected to intestinal ischemia/reperfusion. Intestinal ischemia/reperfusion model was generated by clamping the superior mesenteric artery for 30 min followed by reperfusion for 3 h. Oral administration of atorvastatin at a dose of 10 mg/kg/day lasted 3 days just before induction of intestinal ischemia. At the end of reperfusion period, terminal ileum samples were removed to determine the concentrations of malondialdehyde, reduced glutathione, and myeloperoxidase. Samples were collected also to assess histopathological alterations and contractile response to agonists. Ischemia/reperfusion significantly decreased contractile responses, and this decrease was attenuated by atorvastatin. Pretreatment with atorvastatin caused remarkable decrease in both oxidative stress and neutrophil accumulation. Atorvastatin appeared to be restoring amount of reduced glutathione back to about control level. Furthermore, the pretreatment lowered mucosal damage at histopathological level. Our results suggested that pretreatment with atorvastatin attenuated intestinal muscle dysfunction associated with ischemia/reperfusion. This remarkable effect of atorvastatin is accomplished at least by decreasing oxidative stress and neutrophil accumulation as well as preventing the depletion of reduced glutathione.

Topics: Administration, Oral; Animals; Atorvastatin; Carbachol; Cholinergic Agonists; Dose-Response Relationship, Drug; Glutathione; Heptanoic Acids; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Ileum; In Vitro Techniques; Intestines; Male; Malondialdehyde; Muscle Contraction; Neurotransmitter Agents; Peroxidase; Potassium Chloride; Pyrroles; Rats; Rats, Wistar; Reperfusion Injury; Substance P

Ischemia-reperfusion (I/R) injury, which was commonly seen in the field of hepatic surgical intervention, impaired liver regeneration and predisposed to liver failure. Previous studies have shown gender dimorphic response of the liver for various hepatic stresses including I/R injury, hemorrhagic shock-resuscitation, liver cirrhosis, endotoxemia, and chronic alcoholic consumption, and demonstrated gender dimorphism in hepatocellular dysfunction after experimental trauma and hemorrhage. The objective of this study was to examine the hypothesis that the protective effects of 17beta-estradiol (E2) in hepatic I/R injury were associated with increasing heat-shock protein 70 expression.. Sprague-Dawley male and female rats were randomly divided into male and female sham, I/R, and E2 + I/R groups. The model of reduced-size liver ischemia and reperfusion was used. Except for the sham-operated groups, all rats were subjected to 70% liver ischemia for 45 min followed by resection of the remaining 30% nonischemic lobes and reperfusion of ischemic tissue. For each group, five rats were used to investigate the survival during a week after operation; blood samples and liver tissues were obtained in the remaining animals after 3, 12, and 24 h of reperfusion to assess serum alanine aminotransferase, aspartate aminotransferase, liver tissue NO(2)(-) + NO(3)(-), malondialdehyde content, superoxide dismutase, nitric oxide synthase, and myeloperoxidase activity, Hsp70 expression, and apoptosis ratio.. Compared with I/R groups, male and female E2 + I/R groups showed less I/R-induced injury, and SOD and eNOS activity and Hsp70 expression were increased significantly (P < 0.01). A higher rate of apoptosis was observed in the I/R group versus the E2 + I/R group, a significant increase of MDA, NO(2)(-) + NO(3)(-), and MPO of liver tissues and serum transaminase were also observed in the I/R group versus the E2 + I/R group. The survival rate was significantly higher in the male E2 + I/R group than in the male I/R group.. E2 pretreatment had protective effects on liver in hepatic I/R injury. The mechanism of this protection might be related to overexpression of Hsp70.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Disease Models, Animal; Estradiol; Female; Gene Expression; Hepatocytes; HSP70 Heat-Shock Proteins; Liver; Male; Nitric Oxide; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase

The involvement of bacterial translocation in small intestinal ischemia-reperfusion injuries and the efficacy of using anti-CINC antibodies for treatment were investigated. A model for ischemia-reperfusion injury of the small intestine was constructed by clamping the supramesenteric artery (for 90 min) in rats. Anti-CINC antibodies and saline were given just before the induction of ischemia in the treatment group and the control group, respectively. Six hours after reperfusion, bacteria were detected in the mesenteric lymph nodes, but the 'bacteria-positive' rate was significantly lower in the treatment group than in the control group. Bacterial cultures and endotoxins in the blood were negative in both groups up to 24 h later. The plasma cytokine levels showed similar variations, although the increases were significantly lower after reperfusion in the treatment group. In addition, the degrees of neutrophil infiltration and mucosal injury were attenuated in the small intestine, and the structure of the liver was maintained. Furthermore, the 1-week survival was improved. These results suggest that bacterial translocation occurred predominantly via the lymphatic system and that anti-CINC antibody treatment exerted a protective effect against small intestinal ischemia-reperfusion injury.

Topics: Animals; Antibodies; Bacterial Translocation; Chemokine CXCL1; Chemokines, CXC; Cytokines; Endotoxins; Enterococcus faecalis; Escherichia coli; Intestine, Small; Male; Morganella morganii; Neutrophil Activation; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Remote reperfusion lung injury occurs in patients with vascular occlusion and surgical procedures. Inosine monophosphate (IMP) produced by adenosine monophosphate deaminase (AMPD) 3 is involved in the remote reperfusion injury. The purpose of the present study was to identify whether IMP administration attenuated the remote reperfusion lung injury in a skeletal muscle ischemia-reperfusion model.. A remote reperfusion lung injury was created using reperfusion after the bilateral ligation of the hind-limb. AMPD activity, myeloperoxidase (MPO) activity, IMP, AMPD3 mRNA and tumor necrosis factor (TNF)-alpha in the lungs before and after reperfusion were analyzed. Furthermore, the effects of IMP on these parameters were examined. AMPD3 mRNA, AMPD activity and IMP production in the lungs significantly increased after ischemia-reperfusion with increases in MPO activity, TNF-alpha level and decreased oxygen saturation (SpO(2)). Histological examination of the lungs demonstrated significant neutrophil infiltration and accumulation. IMP administration significantly reduced MPO activity, TNF-alpha and neutrophil infiltration, with ameliorated SpO(2).. Along with the activation of AMPD3, ischemia-reperfusion-induced lung inflammation is associated with increased MPO activity and TNF-alpha level. IMP significantly decreased the lung injury, MPO activity, TNF-alpha and increased SpO(2). These findings may lead to the development of a new therapeutic strategy for remote reperfusion lung injury.

Topics: AMP Deaminase; Animals; Disease Models, Animal; Enzyme Activation; Gene Expression Regulation, Enzymologic; Inosine Monophosphate; Lung; Lung Injury; Male; Mice; Mice, Inbred BALB C; Muscle, Skeletal; Peroxidase; Reperfusion Injury; RNA, Messenger; Tumor Necrosis Factor-alpha

Ischemia reperfusion (I/R) injury following lung transplantation is exacerbated by the destruction of the endothelial cell barrier leading to pulmonary edema and dysregulated activated lymphocyte migration. Sphingosine 1-phosphate (S1P), a G-coupled protein receptor (GPCR) agonist, has been previously shown to promote endothelial cell tight junction formation and prevent monocyte chemotaxis. We asked if S1P treatment could improve pulmonary function and attenuate I/R injury following syngeneic rat lung transplantation. In comparison to vehicle-treated recipients, S1P administered before reperfusion significantly improved recipient oxygenation following transplantation. Improved graft function was associated with reduced inflammatory signaling pathway activation along with attenuated intragraft levels of MIP-2, TNF-alpha and IL-1beta. Moreover, S1P-treated recipients had significantly less apoptotic endothelial cells, pulmonary edema and graft accumulation of neutrophils than did vehicle-treated recipients. Thus our data show that S1P improves lung tissue homeostasis following reperfusion by enhancing endothelial barrier function and blunting monocytic graft infiltration and inflammation.

Topics: Animals; Biomarkers; Bronchoalveolar Lavage Fluid; Caspase 3; Chemokine CXCL2; Edema; In Situ Nick-End Labeling; Inflammation; Interleukin-1beta; Lung Transplantation; Lysophospholipids; Models, Animal; Monokines; Peroxidase; Rats; Rats, Inbred F344; Reperfusion Injury; Sphingosine; Tumor Necrosis Factor-alpha

Testicular torsion-detorsion has been identified as an ischemia-reperfusion type of injury. We elucidated the protective role of heme oxygenase-1 super induction on testicular torsion-detorsion injury.. Adult male Sprague-Dawley rats were randomly allocated to undergo testicular torsion-detorsion, immediately followed by injection of normal saline, the heme oxygenase-1 inducer hemin or hemin plus the heme oxygenase-1 inhibitor tin protoporphyrin. Another set of rats that underwent sham operation, immediately followed by injection of normal saline, hemin or hemin plus tin protoporphyrin, served as controls. Testes were harvested 4 and 24 hours after detorsion, respectively, in the experimental groups or at comparable time points in the control groups.. Histological evaluation confirmed that torsion-detorsion caused significant testicular tissue injury. Torsion-detorsion also caused significant increases in the testicular levels of nitric oxide, malondialdehyde, myeloperoxidase activity and heme oxygenase-1. The heme oxygenase-1 inducer hemin significantly enhanced the heme oxygenase-1 expression induced by torsion-detorsion and in turn attenuated testicular injury, and increases in nitric oxide, malondialdehyde and myeloperoxidase activity. In addition, the protective effects of hemin were significantly offset by the heme oxygenase-1 inhibitor tin protoporphyrin.. Super induction of heme oxygenase-1 protects testes from torsion-detorsion injury.

Topics: Animals; Biomarkers; Disease Models, Animal; Enzyme Inhibitors; Heme Oxygenase-1; Hemin; Immunoblotting; Injections, Intraperitoneal; Male; Malondialdehyde; Metalloporphyrins; Nitric Oxide; Oxidative Stress; Peroxidase; Protoporphyrins; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Spectrophotometry; Spermatic Cord; Spermatic Cord Torsion; Treatment Outcome

Hepatic ischemia-reperfusion injury may lead to remote organ failure with mortal respiratory dysfunction. The aim of the present study was to analyze the possible protective effects of methimazole on lungs after hepatic ischemia-reperfusion injury.. Forty male Wistar albino rats were randomized into five groups: a control group, in which bilateral pulmonary lobectomy was done; a hepatic ischemia-reperfusion group, in which bilateral pulmonary lobectomy was done after hepatic ischemia-reperfusion; a thyroidectomy-ischemia-reperfusion group (total thyroidectomy followed by, 7 days later, bilateral pulmonary lobectomy after hepatic ischemia-reperfusion); a methimazole-ischemia-reperfusion group (following methimazole administration for 7 days, bilateral pulmonary lobectomy was done after hepatic ischemia-reperfusion); and a methimazole +L-thyroxine-ischemia-reperfusion group (following methimazole and L-thyroxine administration for 7 days, bilateral pulmonary lobectomy was performed after hepatic ischemia-reperfusion). Pulmonary tissue specimens were evaluated histopathologically and for myeloperoxidase and malondialdehyde levels.. All of the ischemia-reperfusion intervention groups had higher pulmonary injury scoring indices than the control group (P < 0.001). Pulmonary injury index of the ischemia-reperfusion group was higher than that of both the methimazole-supplemented hypothyroid and euthyroid groups (P = 0028; P = 0,038, respectively) and was similar to that of the thyroidectomized group. Pulmonary tissue myeloperoxidase and malondialdehyde levels in the ischemia-reperfusion group were similar with that in the thyroidectomized rats but were significantly higher than that in the control, and both the methimazole-supplemented hypothyroid and euthyroid groups.. Methimazole exerts a protective role on lungs during hepatic ischemia-reperfusion injury, which can be attributed to its anti-inflammatory and anti-oxidant effects rather than hypothyroidism alone.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Antithyroid Agents; Disease Models, Animal; Hepatic Artery; Liver; Lung; Lung Diseases; Male; Malondialdehyde; Methimazole; Peroxidase; Pneumonectomy; Portal Vein; Rats; Rats, Wistar; Reperfusion Injury; Thyroidectomy; Thyroxine

Endothelial NO synthase (eNOS) is a dynamic enzyme tightly controlled by co- and post-translational lipid modifications, phosphorylation and regulated by protein-protein interactions. Here we have pharmacologically modulated the activation of eNOS, at different post-translational levels, to assess the role of eNOS-derived NO and of these regulatory mechanisms in intestinal injury associated with splanchnic artery occlusion (SAO) shock.. SAO shock was induced by clamping both the superior mesenteric artery and the celiac trunk for 45 min followed by 30 min of reperfusion. During ischemia, 15 min prior to reperfusion, mice were given geldanamycin, an inhibitor of hsp90 recruitment to eNOS, or LY-294002 an inhibitor of phosphatidylinositol 3-kinase (PI3K), an enzyme that initiates Akt-catalysed phosphorylation of eNOS on Ser1179. After 30 min of reperfusion, samples of ileum were taken for histological examination or for biochemical studies.. Either LY-294002 or geldanamycin reversed the increased activation of eNOS and Akt observed following SAO shock. These molecular effects were mirrored in vivo by an exacerbation of the intestinal damage. Histological damage also correlated with neutrophil infiltration, assessed as myeloperoxidase activity, and with an increased expression of the adhesion proteins: ICAM-I, VCAM, P-selectin and E-selectin.. Overall these results suggest that activation of the Akt pathway in ischemic regions of reperfused ileum is a protective event, triggered in order to protect the intestinal tissue from damage induced by ischaemia/reperfusion through a fine tuning of the endothelial NO pathway.

Topics: Animals; Arterial Occlusive Diseases; Benzoquinones; Blotting, Western; Cell Adhesion Molecules; Chromones; Dose-Response Relationship, Drug; Enzyme Activation; Enzyme Inhibitors; Ileum; Intestines; Lactams, Macrocyclic; Male; Mice; Morpholines; Neutrophils; Nitric Oxide Synthase Type III; Peroxidase; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Phosphorylation; Protein Processing, Post-Translational; Proto-Oncogene Proteins c-akt; Reperfusion Injury; Signal Transduction; Splanchnic Circulation

To investigate the hypothesis that the protective effects of curcumin in hepatic warm ischemia/reperfusion (I/R) injury are associated with increasing heat shock protein 70 (Hsp70) expression and antioxidant enzyme activity.. Sixty Sprague-Dawley male rats were randomly divided into sham, I/R, C + I/R groups. The model of reduced-size liver warm ischemia and reperfusion was used. Curcumin (50 mg/kg) was administered by injection through a branch of superior mesenteric vein at 30 min before ischemia in C + I/R group. Five rats were used to investigate the survival during 1 wk after operation in each group. Blood samples and liver tissues were obtained in the remaining animals after 3, 12, and 24 h of reperfusion to assess serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), liver tissue NO(2)(-) + NO(3)(-), malondialdehyde (MDA) content, superoxide dismutase (SOD), catalase (CAT), nitricoxide synthase (NOS) and myeloperoxidase (MPO) activity, Hsp70 expression and apoptosis ratio.. Compared with I/R group, curcumin pretreatment group showed less ischemia/reperfusion-induced injury. CAT and SOD activity and Hsp70 expression increased significantly. A higher rate of apoptosis was observed in I/R group than in C + I/R group, and a significant increase of MDA, NO(2)(-) + NO(3)(-) and MPO level in liver tissues and serum transaminase concentration was also observed in I/R group compared to C + I/R group. Curcumin also decreased the activity of inducible NO synthase (iNOS) in liver after reperfusion, but had no effect on the level of endothelial NO synthase (eNOS) after reperfusion in liver. The 7 d survival rate was significantly higher in C + I/R group than in I/R group.. Curcumin has protective effects against hepatic I/R injury. Its mechanism might be related to the overexpression of Hsp70 and antioxidant enzymes.

Topics: Alanine Transaminase; Animals; Antioxidants; Apoptosis; Aspartate Aminotransferases; Curcumin; Enzyme Activation; Enzyme Inhibitors; Gene Expression Regulation; HSP70 Heat-Shock Proteins; Liver; Male; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Warm Ischemia

The periods of ischemia and reperfusion represent different characteristics by lack of oxygen and reoxygenation. The aim of this experimental spinal cord injury model was to investigate whether resveratrol has protective effects during ischemia or reperfusion and the mechanism of the protection by using N-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide synthase. Rabbits were divided into seven groups according to the time of administration of resveratrol or L-NAME (RI and RR, resveratrol during ischemia or reperfusion; IL and RL, L-NAME during ischemia or reperfusion; RILR, resveratrol during ischemia and L-NAME during reperfusion; LIRR, L-NAME during ischemia and resveratrol during reperfusion; control group). After neurologic evaluation at the twenty-fourth hour of reperfusion, lumbar spinal cords were removed for electron microscopic evaluation, immunohistochemical staining for apoptosis, and malondialdehyde (MDA) and myeloperoxidase (MPO) measurements. The RILR group had the best functional recovery, with a mean 3.6 Tarlov score (P < 0.05), and showed near normal electron microscopic findings (scores of 7.6 +/- 0.9 for the control group and 3.9 +/- 2.9 for the RILR group, P < 0.05). MPO and MDA levels were decreased in all groups compared with the control group, but only the decrement in the RILR group reached statistical significance. Immunohistochemical analysis showed that the groups including resveratrol and L-NAME together had the best staining for apoptosis. Resveratrol exhibits important protection by means of neurologic outcome, histopathologic analysis, and biochemical analysis, especially when used in during ischemia followed by L-NAME administration during reperfusion. Also, resveratrol protects against apoptosis, especially when combined with L-NAME.

Topics: Analysis of Variance; Animals; Antioxidants; Apoptosis; Disease Models, Animal; Enzyme Inhibitors; Hindlimb; Immunohistochemistry; Ischemic Preconditioning; Lumbar Vertebrae; Malondialdehyde; Microscopy, Electron; Movement; NG-Nitroarginine Methyl Ester; Nitrates; Nitrites; Peroxidase; Rabbits; Recovery of Function; Reperfusion; Reperfusion Injury; Resveratrol; Spinal Cord Injuries; Stilbenes; Time Factors; Treatment Outcome

Free radicals are important in development of intestinal ischemia-reperfusion (I/R) injury, leading to intestinal and pulmonary damage. We evaluated the effects of peroxynitrite decomposition catalyst FeTMPyP in infant intestinal I/R. Suckling rats underwent 40 min intestinal ischemia + 90 min reperfusion. At reperfusion, animals received saline or FeTMPyP. Groups were (n = 11 per group): 1) control+saline; 2) I/R+saline; 3) I/R+FeTMPyP. Increased histologic injury and ICAM-1 expression were observed in ileum of both I/R+saline and I/R+FeTMPyP rats, but P-selectin expression was increased in I/R+saline animals only versus controls. Myeloperoxidase (neutrophil infiltration marker) was increased in ileum and lungs of I/R+saline rats, but FeTMPyP prevented this in the ileum. I/R+saline animals showed higher malondialdehyde (lipid peroxidation marker) in ileum and lungs versus both control+saline and I/R+FeTMPyP rats. Glutathione was decreased in all I/R animals, but oxidized and total glutathione were higher in I/R+FeTMPyP than the I/R+saline group. Nitrate+nitrite concentration (systemic nitric oxide production) was elevated in I/R+saline but not in I/R+FeTMPyP animals. FeTMPyP provides limited protection against intestinal I/R in neonatal rats by reducing ileal P-selectin expression, systemic nitric oxide production, neutrophil infiltration in ileum and lipid peroxidation in both lungs and ileum; and preserving intestinal antioxidant capacity.

Topics: Animals; Animals, Suckling; Endothelial Cells; Glutathione; Intercellular Adhesion Molecule-1; Intestinal Mucosa; Intestines; Ischemia; Malondialdehyde; Metalloporphyrins; Nitrates; Nitrites; P-Selectin; Peroxidase; Peroxynitrous Acid; Random Allocation; Rats; Reperfusion Injury; Vascular Cell Adhesion Molecule-1

We recently demonstrated that calcitonin gene-related peptide (CGRP) released from sensory neurons reduces spinal cord injury (SCI) by inhibiting neutrophil activation through an increase in the endothelial production of prostacyclin (PGI(2)). Carperitide, a synthetic alpha-human atrial natriuretic peptide (ANP), reduces ischemia/reperfusion (I/R)-induced tissue injury. However, its precise therapeutic mechanism(s) remains to be elucidated. In the present study, we examined whether ANP reduces I/R-induced spinal cord injury by enhancing sensory neuron activation using rats. ANP increased CGRP release and cellular cAMP levels in dorsal root ganglion neurons isolated from rats in vitro. The increase in CGRP release induced by ANP was reversed by pretreatment with capsazepine, an inhibitor of vanilloid receptor-1 activation, or with (9S, 10S, 12R)-2,3,9,10,11,12-hexahydro-10-hydroxy-9-methyl-1-oxo-9,12-epoxy-1H-diindolo[1,2,3-fg:3',2',1'-kl]pyrrolo[3,4-i][1,6]-benzodiazocine-10-carboxylic acid hexyl ester (KT5720), an inhibitor of protein kinase A (PKA), suggesting that ANP might increase CGRP release from sensory neurons by activating PKA through an increase in the cellular cAMP level. Spinal cord ischemia was induced in rats using a balloon catheter placed in the aorta. ANP reduced mortality and motor disturbances by inhibiting reduction of the number of motor neurons in animals subjected to SCI. ANP significantly enhanced I/R-induced increases in spinal cord tissue levels of CGRP and 6-keto-prostaglandin F(1alpha). a stable metabolite of PGI(2). ANP inhibited I/R-induced increases in spinal cord tissue levels of tumor necrosis factor and myeloperoxidase. Pretreatment with 4'-chloro-3-methoxycinnamanilide (SB366791), a specific vanilloid receptor-1 antagonist, and indomethacin reversed the effects of ANP. These results strongly suggest that ANP might reduce I/R-induced SCI in rats by inhibiting neutrophil activation through enhancement of sensory neuron activation.

Topics: 6-Ketoprostaglandin F1 alpha; Anilides; Animals; Atrial Natriuretic Factor; Calcitonin Gene-Related Peptide; Capsaicin; Carbazoles; Cells, Cultured; Cinnamates; Cyclic AMP; Dose-Response Relationship, Drug; Enzyme Inhibitors; Humans; Indoles; Indomethacin; Male; Neurons, Afferent; Peroxidase; Psychomotor Performance; Pyrroles; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Spinal Cord; Spinal Cord Diseases; TRPV Cation Channels; Tumor Necrosis Factor-alpha

To investigate the effect of hemodilution with high-concentration human serum albumin (HSA) on brain injury in a rat model of chronic cerebral hypoperfusion associated with arteriovenous malformations.. The animal model was established by creating a fistula through an end-to-side anastomosis between the right distal external jugular vein and the ipsilateral common carotid artery, followed by ligation of the left vein draining the transverse sinus and bilateral external carotid arteries. The agent (20% HSA) or control solution (0.9% sodium chloride) was administered intravenously at a dosage of 1% body weight 24 hours before ligation of the fistula. Blood-brain barrier (BBB) disruption was judged by extravasation of Evans blue (EB) dye. EB, water content and the changes of myeloperoxidase (MPO) activity and superoxide dismutase (SOD) activity in rat brains 24 hours after ligation of the fistula were determined.. EB and water content in rat brains of the pre-treated group were significantly decreased compared with the control group accompanied by reduction of MPO activity and enhancement of SOD activity.. Hemodilution with high-concentration HSA has a certain pre-treatment effect on brain injury after ligation of the fistula in rat model of chronic cerebral hypoperfusion, which may be resulted from improved microcirculation, decrease in inflammatory cell infiltration and inactivation of oxygen free radicals.

Topics: Animals; Blood Pressure; Blood-Brain Barrier; Brain Edema; Brain Injuries; Cerebrovascular Circulation; Chronic Disease; Disease Models, Animal; Hemodilution; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Recovery of Function; Reperfusion Injury; Superoxide Dismutase

One of the most important determinants of the outcome of hepatic ischemia and reperfusion (I/R) injury is the onset of the inflammatory response. Interleukin-10 (IL-10) is a potent anti-inflammatory cytokine. It inhibits the production of interleukin-6 (IL-6), which however, also is involved in priming hepatocyte proliferation. The aim of this study was to examine the protective effects and the influence on the regenerative response of exogenous as well as endogenous IL-10 in a rat model of hepatic I/R injury.. Seventy percent Liver I/R was induced in male Wistar rats for 60 min followed by 24 h reperfusion. One group underwent a midline laparotomy with recombinant rat (rr)IL-10 administration (SHAM + IL-10). The other groups underwent 60 min ischemia with administration of saline (I/R + saline), rrIL-10 [at two different time-points, i.e., I/R + IL-10pre(ischemia) and I/R + IL-10end(ischemia)] or anti-rat IL-10 antibody (I/R + antiIL-10).. Parenchymal damage, as assessed by plasma alanine aminotransferase and aspartate aminotransferase, was significantly reduced by rrIL-10 and by endogenous IL-10 (P < 0.05). Also, rrIL-10 significantly reduced IL-6 production and the accumulation of neutrophils in liver and lung tissue, as measured by myeloperoxidase activity. Necrosis and apoptosis were significantly reduced and hepatocyte proliferation was stimulated by rrIL-10.. RrIL-10 and, to a lesser extent, endogenous IL-10, attenuate damage and inflammation, while rrIL-10 also promotes proliferation after hepatic I/R injury in rats. Therefore, rrIL-10 has potential use to prevent I/R injury and to promote liver regeneration after partial liver resection with temporary inflow occlusion.

Topics: Animals; Bile; Cell Proliferation; Hepatocytes; Interleukin-10; Interleukin-6; Liver; Male; Peroxidase; Rats; Rats, Wistar; Recombinant Proteins; Reperfusion Injury

Neutrophil infiltration is a major determinant of ischemia-reperfusion injury (IRI). Statins improve endothelial function by elevating nitric oxide synthase activity and inhibiting adhesion molecule expression and may, therefore, inhibit IRI-induced neutrophil extravasation. Although statins are protective against myocardial IRI and stroke, a role for statins in ameliorating skeletal muscle IRI has not yet been confirmed. This study, therefore, addressed the hypothesis that simvastatin would attenuate the severity of tissue damage during skeletal muscle IRI.. Rats were administered simvastatin for 6 d before 4 h hind limb ischemia and 24 h reperfusion. Neutrophil infiltration was assessed using myeloperoxidase (MPO) assays and tissue damage by quantitative immunohistochemical analysis of collagen IV. The effect of reducing nitric oxide levels on the severity of IRI was assessed by administering the NOS inhibitor, N-Imino-L-ornithine (L-NIO), before ischemia.. Simvastatin significantly inhibited IRI-induced MPO activity but not collagen degradation in postischemic skeletal muscle. Inhibition of nitric oxide synthase by L-NIO markedly inhibited neutrophil infiltration and protected against IRI-induced collagen degradation. When both simvastatin and L-NIO were administered before IRI, the IRI-induced elevation in MPO activity was completely inhibited. However, paradoxically, simvastatin counteracted the protective effect of L-NIO against IRI-induced collagen IV degradation.. The inhibition by simvastatin of IRI-induced neutrophil infiltration in skeletal muscle suggests that statins may be a useful therapy to attenuate the severity of IRI but their precise mechanisms of action remains to be determined. Nitric oxide also plays a cytotoxic, rather than protective, role in mediating IRI in this model.

Topics: Animals; Collagen Type IV; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Male; Matrix Metalloproteinase 9; Muscle, Skeletal; Neutrophil Infiltration; Ornithine; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Simvastatin

Pyrrolidine dithiocarbamate (PDTC) is a low-molecular-weight thiol antioxidant and potent inhibitor of nuclear factor-kappaB (NF-kappaB) activation. It has been shown to attenuate local harmful effects of ischemia/reperfusion (I/R) injury in many organs. In recent animal studies, a delaying effect of remote organ I/R injury on the healing of colonic anastomoses has been demonstrated. In this study we investigated whether PDTC prevents harmful systemic effects of superior mesenteric I/R on left colonic anastomosis in rats.. Anastomosis of the left colon was performed in 40 rats randomly allocated into the following four groups: (1) Sham-operated group (group I, n = 10)-simultaneously with colonic anastomosis, the superior mesenteric artery and collateral branches divided from the celiac axis and the inferior mesenteric artery were isolated but not occluded. (2) Sham+PDTC group (group II, n = 10)-identical to sham-operated rats except for the administration of PDTC (100 mg/kg IV bolus) 30 minutes prior to commencing the experimental period. (3) I/R group (group III, n = 10)-60 minutes of intestinal I/R by superior mesenteric artery occlusion. (4) PDTC-treated group (group IV, n = 10)-PDTC 100 mg/kg before and after the I/R. On postoperative day 6, all animals were sacrificed, and anastomotic bursting pressures were measured in vivo. Tissue samples were obtained for investigation of anastomotic hydroxyproline (HP) contents, perianastomotic malondialdehyde (MDA) levels, myeloperoxidase activity (MPO), and glutathione (GSH) level.. There was a statistically significant decrease in anastomotic bursting pressure values, tissue HP content and GSH level, along with an increase in MDA level and MPO activity in group III, when compared to groups I, II, and IV (p < 0.05). However, PDTC treatment led to a statistically significant increase in anastomotic bursting pressure values, tissue HP content and GSH level, along with a decrease in MDA level and MPO activity in group IV (p < 0.05).. This study showed that PDTC treatment significantly prevented the delaying effect of remote organ I/R injury on anastomotic healing in the colon. Further clinical studies are needed to clarify whether PDTC may be a useful therapeutic agent for increasing the safety of the anastomosis during particular operations where remote organ I/R injury occurs.

Topics: Anastomosis, Surgical; Animals; Antioxidants; Colon; Colonic Diseases; Disease Models, Animal; Glutathione; Hydroxyproline; Male; Malondialdehyde; Peroxidase; Pyrrolidines; Random Allocation; Rats; Rats, Wistar; Reperfusion Injury; Thiocarbamates; Wound Healing

Early acute graft dysfunction continues to be a problem after lung transplantation and results in significant postoperative morbidity and mortality. This study assessed the protective effect of N-acetylcysteine (NAC) on posttransplant lung ischemia-reperfusion injury.. Rat single-lung transplantation was performed in two experimental groups (n = 5) after 18 hours of cold (4 degrees C) ischemia. Group I was the ischemic control (IC) group. In group II (NAC), donor and recipient animals were treated with an intraperitoneal injection of 150 mg/kg NAC 15 minutes before harvest, and recipient animals were treated again before reperfusion. After 2 hours of reperfusion, oxygenation was measured. Lung tissue was assessed for lipid peroxidation, neutrophil infiltration, and reduced glutathione level. Peak airway pressure was recorded throughout the reperfusion period.. Rats treated with NAC showed significantly better oxygenation (184.5 +/- 83.3 mm Hg versus 67.3 +/- 16.4 mm Hg, p = 0.016) and reduced lipid peroxidation (7.34 +/- 1.9 micromol/g versus 17.46 +/- 10.6 micromol/g, p = 0.016). Lung tissue reduced glutathione levels were 6.8 +/- 0.9 microM in the IC group and 20.6 +/- 2.4 microM in the NAC group (p = 0.004). Peak airway pressure at the end of the reperfusion period was 14.4 +/- 1.6 cm H2O in the NAC group, and 19.2 +/- 2.2 cm H2O in the IC group (p = 0.008). Myeloperoxidase activity and the ratio of wet-to-dry weight did not differ between the groups.. In this model, exogenously administered NAC effectively protected the lungs from reperfusion injury after prolonged ischemia.

Topics: Acetylcysteine; Animals; Glutathione; Lipid Peroxidation; Lung; Lung Transplantation; Male; Peroxidase; Rats; Rats, Inbred F344; Reperfusion Injury; Superoxides; Thiobarbituric Acid Reactive Substances

Lung ischemia-reperfusion injury (LIRI) is postulated to occur biphasically. Donor pulmonary macrophages mediate early injury, and neutrophil-dependent injury predominates in the later phase of LIRI. We hypothesized that the biphasic response to LIRI would be attenuated by the administration of gadolinium, a known pulmonary macrophage inhibitor, and inhaled nitric oxide (NO), a pulmonary vasodilator that also interferes with neutrophil chemotaxis.. Using our isolated, ventilated, blood-perfused rabbit lung model, study groups (n = 10 per group) underwent two hours of reperfusion after 18 hours of cold ischemia (4 degrees C). Lungs received gadolinium alone, or inhaled NO in the presence or absence of macrophage inhibition with gadolinium.. Compared with control animals, pulmonary macrophage inhibition with the concurrent administration of inhaled NO increased lung compliance (p < 0.01) and oxygenation (p = 0.03), while also decreasing pulmonary artery pressure (p < 0.01), myeloperoxidase content by 63% (p < 0.01), wet to dry ratios by 23% (p < 0.01), and lung tissue (p < 0.01) and bronchoalveolar lavage tumor necrosis factor-alpha (TNF-alpha) protein levels (p < 0.01).. The severity of LIRI was most significantly reduced by the inhibition of pulmonary macrophages and the concomitant use of inhaled NO. Pulmonary macrophages, likely through the elaboration of proinflammatory cytokines such as TNF-alpha, not only cause early injury themselves but also prime cells such as neutrophils to injure lungs in the later stages of LIRI. The LIRI was effectively blunted by the reduction of macrophage-dependent injury by gadolinium while inhaled NO also attenuated injury by reducing pulmonary hypertension and minimizing neutrophil sequestration.

Topics: Administration, Inhalation; Animals; Blood Pressure; Female; Gadolinium; Lung; Macrophages, Alveolar; Male; Neutrophils; Nitric Oxide; Peroxidase; Rabbits; Reactive Oxygen Species; Reperfusion Injury; Tumor Necrosis Factor-alpha

Our previous experimental studies showed that dauricine could protect the brain from ischemic damage, but the underlying mechanisms were unknown. In this study, we investigated the effect of dauricine on the changes of the inflammation process induced by ischemia/reperfusion (I/R). After I/R, the enzyme activity of MPO, the expression of ICAM-1 and the transcription of IL-1beta and TNF-alpha mRNA were all significantly increased (p < 0.01). And after treatment with dauricine, they were all significantly reduced compared to the vehicle-treated I/R group (p < 0.05 or p < 0.01). These results suggest that dauricin attenuates the inflammation process induced by I/R. The neuroprotective effect of dauricine may partly due to the inhibition acute inflammation induced by I/R.

Topics: Alkaloids; Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzylisoquinolines; Brain; Cell Movement; Inflammation; Intercellular Adhesion Molecule-1; Interleukin-1beta; Male; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; RNA, Messenger; Tetrahydroisoquinolines; Transcription, Genetic; Tumor Necrosis Factor-alpha

Pyrrolidine dithiocarbamate (PDTC) is a low-molecular-weight thiol antioxidant and potent inhibitor of nuclear factor-kappaB (NF-kappaB) activation. It has been shown to attenuate harmful effects of ischemia/reperfusion (I/R) injury in many organs. In recent animal studies, destructive effects of reperfusion injury has been demonstrated. In this study, we aimed to investigate whether PDTC prevents harmful effects of superior mesenteric I/R injury in rats.. Wistar-albino rats were randomly allocated into the following 4 groups: (1) sham-operated group--these animals underwent laparotomy without I/R injury (group I, n = 12); (2) sham+PDTC group--identical to sham-operated rats except for the administration of PDTC (100 mg/kg intravenous bolus) 30 minutes prior to the commencement of the experimental period (group II, n = 12); (3) I/R group--these animals underwent laparotomy and 60 minutes of ischemia followed by 120 minutes of reperfusion (group III, n = 12); (4) PDTC-treated group (100 mg/kg, intravenously, before the I/R, group IV, n = 12). All animals were killed, and intestinal tissue samples were obtained for investigation of intestinal mucosal injury, myeloperoxidase (MPO) activity, malondialdehyde (MDA) levels, glutathione (GSH) levels, and intestinal edema.. There was a statistically significant decrease in GSH levels, along with an increase in intestinal mucosal injury scores, MPO activity, MDA levels, and intestinal tissue wet-to-dry weight ratios in group III when compared to groups I, II, and IV (P < .05). However, PDTC treatment led to a statistically significant increase in GSH levels, along with a decrease in intestinal mucosal injury scores, MPO activity, MDA levels, and intestinal tissue wet-to-dry weight ratios in group IV (P < .05).. This study showed that PDTC treatment significantly prevented the reperfusion injury caused by superior mesenteric I/R. Further clinical studies are needed to clarify whether PDTC may be a useful therapeutic agent to use in particular operations where the reperfusion injury occurs.

Topics: Animals; Antioxidants; Glutathione; Intestine, Small; Male; Malondialdehyde; Peroxidase; Pyrrolidines; Rats; Rats, Wistar; Reperfusion Injury; Thiocarbamates; Warm Ischemia

An increasing number of patients were undergoing cardiac surgery with cardiopulmonary bypass (CPB) and more attention had been paid to hepatic injury after CPB. This study was designed to test the hypothesis that melatonin and N-acetylcysteine (NAC) could attenuate hepatic injury induced by CPB in rats.. Male Sprague Dawley rats were randomly divided into four groups: sham, control (CPB + placebo), NAC (CPB + 250 mg/kg N-acetylcysteine), and melatonin (CPB + 20 mg/kg melatonin). Blood samples were collected at the beginning, at the end of CPB, and at 0.5, 1, 2, 3, and 24 h postoperation. Liver samples were harvested at 24 h after the operation.. In the control group, the levels of serum liver enzymes and tumor necrosis factor-alpha, activities of inducible nitric oxide synthase, malondialdehyde, and myeloperoxidase in liver tissue were significantly increased. In addition, swollen hepatocytes, vacuolization, and congestion in sinusoids were observed. These changes were markedly reversed in both NAC and melatonin groups. Furthermore, the glutathione content and liver antioxidative enzymes activities were significantly decreased in the control group compared with the sham group. However, the levels of these antioxidants were markedly elevated after NAC or melatonin treatment compared with placebo treatment.. Our findings showed that NAC and melatonin had acceptably beneficial effects against the CPB-induced hepatic injury.

Topics: Acetylcysteine; Animals; Apoptosis; Cardiopulmonary Bypass; Disease Models, Animal; Free Radical Scavengers; Glutathione; Liver; Male; Malondialdehyde; Melatonin; Nitric Oxide Synthase; Oxidative Stress; Peroxidase; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

The present study aimed to investigate the possible beneficial effects of the cysteinyl leukotriene-1 receptor antagonist montelukast on contractility and oxidant damage after ischaemia/reperfusion (I/R) of rat urinary bladder. The abdominal aorta of Sprague-Dawley rats was occluded to induce I/R. Montelukast (10 mg kg(-1)) or saline was administered intraperitoneally before I/R. In the sham-operated group, the abdominal aorta was left intact and the animals were treated with montelukast or saline. After decapitation, the bladder was removed and the tissue was either used for functional studies or stored for biochemical assays. In the I/R group, the isometric contractile responses of the bladder strips to carbachol (10(-8)-10(-4) M) were lower than those of the control group and were reversed by treatment with montelukast. Lipid peroxidation and myeloperoxidase activity of the bladder tissues in the I/R group were greater than in the sham-operated group. Montelukast treatment in the I/R group decreased these parameters compared with I/R alone. Similarly, the significant decrease in tissue glutathione level in the I/R group compared with controls was also prevented by montelukast. Treatment with montelukast almost completely reversed the low contractile responses of rat urinary bladder to carbachol and prevented oxidative tissue damage following I/R.

Topics: Acetates; Animals; Cyclopropanes; Female; Glutathione; Isometric Contraction; Leukotriene Antagonists; Lipid Peroxidation; Male; Muscle, Smooth; Oxidative Stress; Peroxidase; Quinolines; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sulfides; Urinary Bladder; Urinary Bladder Diseases

In this study, we have investigated the role of the cannabinoid CB(2) (CB(2)) receptor in an in vivo mouse model of hepatic ischemia/reperfusion (I/R) injury. In addition, we have assessed the role of the CB(2) receptor in TNF-alpha-induced ICAM-1 and VCAM-1 expression in human liver sinusoidal endothelial cells (HLSECs) and in the adhesion of human neutrophils to HLSECs in vitro. The potent CB(2) receptor agonist HU-308, given prior to the induction of I/R, significantly attenuated the extent of liver damage (measured by serum alanine aminotransferase and lactate dehydrogenase) and decreased serum and tissue TNF-alpha, MIP-1alpha, and MIP-2 levels, tissue lipid peroxidation, neutrophil infiltration, DNA fragmentation, and caspase 3 activity. The protective effect of HU-308 against liver damage was also preserved when given right after the ischemic episode. HU-308 also attenuated the TNF-alpha-induced ICAM-1 and VCAM-1 expression in HLSECs, which expressed CB(2) receptors, and the adhesion of human neutrophils to HLSECs in vitro. These findings suggest that selective CB(2) receptor agonists may represent a novel, protective strategy against I/R injury by attenuating oxidative stress, inflammatory response, and apoptosis.

Topics: Alanine Transaminase; Animals; Apoptosis; Cannabinoid Receptor Agonists; Cannabinoids; Cell Adhesion; Chemokines; Endothelial Cells; Humans; Inflammation; Inflammation Mediators; Intercellular Adhesion Molecule-1; Ischemia; L-Lactate Dehydrogenase; Leukocytes; Lipid Peroxidation; Liver; Mice; Oxidative Stress; Peroxidase; Reperfusion Injury; Tumor Necrosis Factor-alpha; Vascular Cell Adhesion Molecule-1

Tissue damage caused by ischemia/reperfusion injury (IRI) of the intestine may lead to organ dysfunction in several clinical conditions, and is associated with increased incidence of chronic rejection after transplantation. Heme oxygenase-1 (HO-1) is a stress-inducible protein capable of modulating inflammation, oxidative stress, and cell death. The aim of the present study was to assess the effects of HO-1 upregulation on intestinal IRI.. Lewis rats (seven groups, n=6 each) underwent intestinal warm ischemia induced by clamping the superior mesenteric artery and by ligating the inferior mesenteric artery for 60 min. After 120 or 240 min of reperfusion, tissue samples were collected for analysis. Cobalt protoporphyrin (CoPP) was administered IP at 10 or 20mg/kg 24h before IRI, to induce HO-1 upregulation. Control animals received vehicle alone. Tissue injury measurements included the following: histological changes, tissue myeloperoxidase (MPO) activity, nitrate/nitrite levels, and IL-6 levels.. A significant HO-1 upregulation was demonstrated in pre-treated animals (p<0.05, 95% CI: -0.84 to -0.05). Intestinal IL-6 mRNA expression levels were significantly reduced in animals treated with CoPP 20mg/kg after 240 min of IRI (p<0.05, 95% CI: 0.09-2.25). Significant reduction in MPO activity and NO products was observed in treated animals when compared to controls (p<0.01, 95% CI: 0.07-0.24 and p<0.01, 95% CI: 5.58-12.75, respectively).. Induction of HO-1 by CoPP administration before IRI was resulted in a significant reduction of intestinal tissue injury. Developing strategies to induce HO-1 upregulation before surgery will be important to reduce IRI in the clinical setting.

Topics: Analysis of Variance; Animals; Blotting, Western; Heme Oxygenase-1; Interleukin-6; Intestines; Male; Mesenteric Arteries; Nitric Oxide; Peroxidase; Protoporphyrins; Rats; Rats, Inbred Lew; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; Up-Regulation

Ischemia and reperfusion (I/R) damage involves adhesion and transmigration of lymphocytes and neutrophils. FTY720 is an immunosuppressive agent that reduces the number of neutrophils and monocytes in peripheral blood as well as tissue lymphocyte infiltration. This study investigated the effect of FTY720 during hind limb I/R.. Male C57/BL6 mice underwent temporary ligation of the infrarenal aorta for 4 hours. After 48 hours of reperfusion, animals were killed by exsanguination. Tissue myeloperoxidase content reflecting neutrophil infiltration and reverse transcription polymerase chain reaction analysis of local cytokine transcription in lung, liver, and kidney were performed.. After I/R, treatment with FTY720 improved survival and prevented upregulation of pro- and anti-inflammatory cytokines in evaluated organs, whereas no changes were detected in myeloperoxidase content after treatment with FTY720.. Whereas neutrophil infiltration was not affected by treatment with FTY720, other immunocompetent or intrinsic cells appear to be involved in changes of cytokine production in different organs.

Topics: Analysis of Variance; Animals; Biomarkers; Cytokines; Disease Models, Animal; Fingolimod Hydrochloride; Hindlimb; Immunosuppressive Agents; Interleukin-1; Ischemia; Male; Mice; Mice, Inbred C57BL; Peroxidase; Probability; Propylene Glycols; Random Allocation; Reference Values; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; Sensitivity and Specificity; Sphingosine; Survival Rate

Ischemia/reperfusion injury (IRI) remains an important problem in clinical transplantation. Following ischemia, phosphatidylserine (PS) translocates to surfaces of endothelial cells (ECs) and promotes the early attachment of leukocytes/platelets, impairing microvascular blood flow. Diannexin, a 73 KD homodimer of human annexin V, binds to PS, prevents attachment of leukocytes/platelets to EC, and maintains sinusoidal blood flow. This study analyzes whether Diannexin treatment can prevent cold IRI in liver transplantation. Rat livers were stored at 4 degrees C in UW solution for 24 h, and then transplanted orthotopically (OLT) into syngeneic recipients. Diannexin (200 microg/kg) was infused into: (i) donor livers after recovering and before reperfusion, (ii) OLT recipients at reperfusion and day +2. Controls consisted of untreated OLTs. Both Diannexin regimens increased OLT survival from 40% to 100%, depressed sALT levels, and decreased hepatic histological injury. Diannexin treatment decreased TNF-alpha, IL-1beta, IP-10 expression, diminished expression of P-selectin, endothelial ICAM-1, and attenuated OLT infiltration by macrophages, CD4 cells and PMNs. Diannexin increased expression of HO-1/Bcl-2/Bcl-xl, and reduced Caspase-3/TUNEL+ apoptotic cells. Thus, by modulating leukocyte/platelet trafficking and EC activation in OLTs, Diannexin suppressed vascular inflammatory responses and decreased apoptosis. Diannexin deserves further exploration as a novel agent to attenuate IRI, and thereby improve OLT function/increase organ donor pool.

Topics: Alanine Transaminase; Animals; Annexin A5; Apoptosis; Caspase 3; Heme Oxygenase-1; Liver Transplantation; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

We investigated the roles of NO/NOS isoforms in the pathogenesis of ischemia/reperfusion (I/R)-induced gastric injury in mouse stomachs.. Under urethane anesthesia, the celiac artery was clamped, and then reperfusion was established 30 min later by removal of the clamp. After a 60-min reperfusion, the stomach was examined for macroscopic lesions.. Following I/R, hemorrhagic lesions were generated in the mucosa, although ischemia alone caused no visible damage. Prior administration of L-NAME (a nonselective NOS inhibitor) significantly aggravated these lesions, in a L-arginine-inhibitable manner. By contrast, the selective iNOS inhibitor 1400W significantly prevented the occurrence of I/R-induced gastric lesions. The mucosal MPO activity was increased after I/R, and this response was enhanced and attenuated by prior administration of L-NAME and 1400W, respectively. Interestingly, the later treatment with L-NAME, given 10 min before reperfusion, significantly reduced the severity of the I/R-induced gastric damage, in a L-arginine-dependent manner. The expression of iNOS mRNA was up-regulated in the stomach following I/R, with an increase of mucosal NO content, and the NO production was significantly inhibited by both L-NAME and 1400W.. Endogenous NO plays a dual role in the pathogenesis of IR-induced gastric damage; NO/cNOS is protective while NO/iNOS is proulcerogenic during I/R.

Topics: Animals; Enzyme Inhibitors; Gastric Acid; Gastric Mucosa; Imines; Male; Mice; Mice, Inbred C57BL; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase; Peroxidase; Reperfusion Injury; Stomach Ulcer; Up-Regulation

1. The aim of the present study was to investigate the role of proteasome in the pathogenesis of liver injury induced by intestinal ischaemia-reperfusion (I/R) and the effect of the proteasome inhibitor lactacystin on neutrophil infiltration, intracellular adhesion molecule (ICAM)-1 and nuclear factor (NF)-kappaB expression in the liver tissues of rats. 2. Thirty-two Wistar rats were randomly divided into four groups (n = 8 in each group) as follows: (i) a control, sham-operated group; (ii) an I/R group subjected to 1 h intestinal ischaemia and 4 h reperfusion; (iii) a group pretreated with 0.2 mg/kg lactacystin 1 h before intestinal I/R; and (iv) a group pretreated with 0.6 mg/kg lactacystin 1 h before intestinal I/R. Liver and intestine histology were observed. Serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH), as well as 20S proteasome activity in circulating white blood cells, were measured. Myeloperoxidase (MPO) activity in liver tissues and the immunohistochemical expression of liver NF-kappaB and ICAM-1 were assayed. In addition, a western blot of liver NF-kappaB was performed. 3. Compared with the sham-operated control group, liver and intestine injury was induced by intestinal I/R, characterized as histological damage including oedema, haemorrhage and infiltration by inflammatory cells, as well as a significant increase in serum AST (365 +/- 121 vs 546 +/- 297 IU/L, respectively; P < 0.05), ALT (65 +/- 23 vs 175 +/- 54 IU/L, respectively; P < 0.01) and LDH levels (733 +/- 383 vs 1434 +/- 890 IU/L, respectively; P < 0.05). Compared with the control group, MPO activity in the liver tissues increased significantly in the I/R group (2.05 +/- 0.69 vs 3.42 +/- 1.11 U/g, respectively; P < 0.05). Strong positive expression of liver ICAM-1 and NF-kappaB p65 was observed. 4. Compared with the intestinal I/R group, administration of 0.6 mg/kg lactacystin markedly reduced 20S proteasome activity in circulating white blood cells (15.47 +/- 4.00 vs 2.07 +/- 2.00 pmol 7-amino-4-methylcoumarin (AMC)/s per mg, respectively; P < 0.01) and ameliorated liver injury, which was demonstrated by decreased levels of serum AST (546 +/- 297 vs 367 +/- 86 IU/L, respectively; P < 0.05), ALT (175 +/- 54 vs 135 +/- 26 IU/L, respectively; P < 0.05) and LDH (1434 +/- 890 vs 742 +/- 218 IU/L, respectively; P < 0.05) and a reduced liver pathological score (2.13 +/- 0.64 vs 1.25 +/- 0.46, respectively; P < 0.01). Compar

Topics: Acetylcysteine; Alanine Transaminase; Animals; Aspartate Aminotransferases; Cysteine Proteinase Inhibitors; Disease Models, Animal; Dose-Response Relationship, Drug; Feasibility Studies; Intercellular Adhesion Molecule-1; Intestines; L-Lactate Dehydrogenase; Liver; Liver Diseases; Male; Neutrophil Infiltration; Peroxidase; Proteasome Endopeptidase Complex; Rats; Rats, Wistar; Reperfusion Injury; Transcription Factor RelA

This study analyzes how toll-like receptor 4 (TLR4) signaling in the donor organ affects the ischemia and reperfusion injury (IRI) sequel following liver transplantation. Isogenic orthotopic liver transplantations (OLTs) with rearterialization were performed in groups of wild-type (WT) and TLR4 knockout (KO) mice after donor liver preservation in University of Wisconsin solution at 4 degrees C for 24 hours. Unlike WT OLTs, TLR4-deficient OLTs transplanted to either WT or TLR4 KO recipients suffered significantly less hepatocellular damage, as evidenced by serum alanine aminotransferase levels, and histological Suzuki's grading of liver IRI. Disruption of TLR4 signaling in OLTs decreased local neutrophil sequestration, CD4+ T cell infiltration, interferon (IFN)-gamma-inducible protein 10 (CXCL10) and an intercellular adhesion molecule (ICAM-1), as well as tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-2, and IFN-gamma, yet increased IL-4 and IL-10 expression. The well-functioning OLTs from TLR4 KO donors revealed attenuated activity of capase-3, and enhanced heme oygenase-1 (HO-1) expression, along with decreased levels of apoptotic endothelial cells/hepatocytes, as compared with WT OLTs with intact TLR4 signaling. Thus, the functional sentinel TLR4 complex in the donor organ plays a key role in the mechanism of hepatic IRI after OLT. Disruption of TLR4 pathway downregulated the early proinflammatory responses and ameliorated hepatic IRI. These results provide the rationale to locally modify innate TLR4 signaling in the donor organ to more efficiently control the adaptive posttransplantation IRI-dependent responses.

Topics: Animals; Apoptosis; Blotting, Western; Caspase 3; Disease Models, Animal; DNA; Gene Expression; Immunohistochemistry; Interleukins; Liver; Liver Transplantation; Male; Mice; Mice, Inbred C57BL; Peroxidase; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; Signal Transduction; Toll-Like Receptor 4

To investigate the protective effects of resveratrol on inflammatory process induced by focal cerebral ischemia-reperfusion in rats.. Rats were pretreated with resvreratrol at the dose of 10, 20, 40 mg kg(-1) for 7 days and then subjected to cerebral ischemia/reperfusion induced by a middle cerebral artery occlusion (MCAO). The infarct volume and the neurological deficit were determined by the method of TTC (2, 3, 5-triphenylterazolium chloride) staining and Longa's score. The permeability of blood-brain barrier (BBB) was evaluated by measurement of the evans blue (EB) content in the brain with spectrophotometer. The content of interleukin-lbeta, interleukin-6 (IL-6, IL-1beta) in serum and tumor necrosis factor-alpha (TNF-alpha), myeloperoxidase (MPO) in brain were determined by radio-immunoassay and ELISA assay.. Resveratrol reduced infarct volume, ameliorated the neurological deficit and the permeability of BBB, the content of IL-6, IL-1beta in serum and TNF-alpha, MPO activity in brain tissue also were significantly decreased.. These results showed that resveratrol had protective effects on cerebral injury by inhibiting the releasing of the inflammatory mediators after ischemia/reperfusion injury.

Topics: Animals; Blood-Brain Barrier; Brain; Brain Ischemia; Infarction, Middle Cerebral Artery; Inflammation Mediators; Interleukin-1beta; Interleukin-6; Male; Neuroprotective Agents; Peroxidase; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Resveratrol; Stilbenes; Tumor Necrosis Factor-alpha

In this study, the involvement of 5-HT2A receptors on mesenteric ischemia-reperfusion injury was examined in mice. Intestinal ischemia produced by 45 min occlusion of superior mesenteric artery was followed by 24h reperfusion (I/R). The 5-HT2A selective antagonist, ketanserin (0.5 mgkg(-1)) or the 5-HT2A agonist DOI (0.25 mgkg(-1)) was intravenously administered before ischemia and 8h after the beginning of reperfusion. The effects were compared with those obtained in sham operated animals (S). Ketanserin prevented the upper gastrointestinal transit delay induced by I/R (P<0.01), protected intestine from leukocyte recruitment as indicated by jejunal myeloperoxidase activity (P<0.05) and reverted Evans Blue extravasation elicited by I/R in lung, colon and jejunum (P<0.05). On the other hand, 5-HT2A activation by DOI mimicked the effects of I/R in S mice prolonging small intestine transit (P<0.05) and enhancing neutrophil accumulation in jejunal tissues (P<0.05). Furthermore, the reduction of ADP-induced platelet aggregation in plasma of I/R mice was prevented by ketanserin treatment. All together, these findings support the critical involvement of 5-HT2A receptor subtype in mediating the damage induced by mesenteric I/R in mice.

Topics: Amphetamines; Animals; Capillary Permeability; Female; Gastrointestinal Transit; Intestines; Ketanserin; Leukocytes; Lipid Peroxidation; Lung; Malondialdehyde; Mesenteric Artery, Superior; Mice; Peroxidase; Platelet Aggregation; Receptor, Serotonin, 5-HT2A; Reperfusion Injury; Serotonin 5-HT2 Receptor Agonists; Serotonin 5-HT2 Receptor Antagonists; Serotonin Antagonists; Serotonin Receptor Agonists; Tumor Necrosis Factor-alpha

Reactive oxygen species have been implicated in the development of hepatic ischemia/reperfusion (I/R) injury. I/R injury remains an important problem in massive hepatectomy and organ transplantation. The aim of this study was to examine the effect of edaravone, a newly synthesized free radical scavenger, on I/R injury in the remnant liver after partial hepatectomy in rats.. Partial (70%) hepatic ischemia was induced in rats by occluding the hepatic artery, portal vein, and bile duct to left and median lobes of liver. Total hepatic ischemia (Pringle maneuver) was induced by occluding the hepatoduodenal ligament. Edaravone was intravenously administered to rats just before reperfusion and partial (70%) hepatectomy was performed just after reperfusion.. Edaravone significantly reduced the increases in the levels of serum alanine aminotransferase and aspartate aminotransferase in rats with liver injury induced by 90-min of partial ischemia followed by 120-min of reperfusion. Histopathological analysis showed that edaravone prevented inflammatory changes in the livers with I/R injury. Edaravone also decreased the levels of myeloperoxidase activity, which is an index of neutrophil infiltration, and interleukin-6 mRNA, which is a proinflammatory cytokine. Additionally, edaravone improved the survival rate in partial hepatectomy rats with I/R injury induced by the Pringle maneuver.. Edaravone administration prior to reperfusion protected the liver against I/R injury. Edaravone also improved the function of the remnant liver with I/R injury after partial hepatectomy. Therefore, edaravone may have applicability for major hepatectomy and liver transplantation in the clinical setting.

Topics: Animals; Antipyrine; Edaravone; Free Radical Scavengers; Gene Expression Regulation; Hepatectomy; Interleukin-6; Liver; Liver Diseases; Male; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; RNA, Messenger; Survival Rate

In this study the role of myeloperoxidase (MPO) in a murine (C57BL/6) model of ischemia and reperfusion (I/R)-induced renal failure was investigated. The renal function after I/R was analyzed in MPO-deficient (Mpo(-/-)) mice and compared with wild-type (WT) controls. A significant reduction in renal function loss (blood urea nitrogen) was observed after 24 hours of reperfusion of ischemically damaged kidneys in Mpo(-/-) mice compared with I/R WT controls (I/R Mpo(-/-) = 31.3 +/- 1.7 mmol/L versus I/R WT = 42.8 +/- 2.1 mmol/L, sham = 7.0 +/- 0.5 mmol/L; P = 0.003). The early reperfusion phase (2 hours of reperfusion) was characterized by a substantial increase in apoptosis and early complement activation, surprisingly similar in Mpo(-/-) and WT mice. Improved renal function in Mpo(-/-) mice after extended reperfusion was accompanied by a reduced neutrophil influx (P = 0.017) compared with WT controls. Activation and deposition of complement was not significantly reduced in Mpo(-/-) mice compared with WT controls after 24 hours of reperfusion, indicating no specific in vivo role for MPO in activating complement after renal I/R. Taken together, these results demonstrated an important contribution of MPO in the induction of organ damage after renal I/R by influencing critical factors such as neutrophil extravasation but not complement activation.

Topics: Animals; Apoptosis; Complement Activation; Kidney Diseases; Mice; Mice, Mutant Strains; Neutrophils; Peroxidase; Reperfusion Injury

Ischaemia-reperfusion injury is still a major problem after lung transplantation. Several reports describe the benefits of controlled graft reperfusion. In this study the role of length of the initial pressure-controlled reperfusion (PCR) was evaluated in a model of isolated, buffer-perfused rabbit lungs.. Heart-lung blocks of 25 New Zealand white rabbits were used. After measurement of baseline values (haemodynamics and gas exchange) the lungs were exposed to 120 minutes of hypoxic warm ischaemia followed by repeated measurements during reperfusion. Group A was immediately reperfused using a flow of 100 ml/min whereas groups B, C and D were initially reperfused with a maximum pressure of 5 mmHg for 5, 15 or 30 minutes, respectively. The control group had no period of ischaemia or PCR.. Uncontrolled reperfusion (group A) caused a significant pulmonary injury with increased pulmonary artery pressures (PAP) and pulmonary vascular resistance and a decrease in oxygen partial pressure (PO2), tidal volume and in lung compliance. All groups with PCR had a significantly higher PO2 for 5 to 90 min after start of reperfusion. At 120 min there was also a significant difference between group B (264 +/- 91 mmHg) compared to groups C and D (436 +/- 87 mmHg; 562 +/- 20 mmHg, p < 0.01). All PCR groups showed a significant decrease of PAP compared to group A.. Uncontrolled reperfusion results in a severe lung injury with rapid oedema formation. PCR preserves pulmonary haemodynamics and gas exchange after ischaemia and might allows for recovery of the impaired endothelial function. 30 minutes of PCR provide superior results compared to 5 or 15 minutes of PCR.

Topics: Animals; Disease Models, Animal; Lung; Lung Compliance; Lung Injury; Male; Organ Size; Oxygen; Peroxidase; Pressure; Pulmonary Artery; Rabbits; Reperfusion; Reperfusion Injury; Vascular Resistance; Warm Ischemia

Remote preconditioning (RPC) can protect from ischemia/reperfusion injury (IRI). We investigated the influence of RPC in pancreatic IRI.. Wistar rats were randomized to 2 hours of ischemia and 2 hours of reperfusion of a pancreatic tail segment with or without 15 minutes of infrarenal ischemia 60 minutes before IRI. Microcirculatory measurements before ischemia and 1 and 2 hours after reperfusion included functional capillary density and leukocyte adherence in postcapillary venules, quantified by intravital fluorescence microscopy. Histology and tissue myeloperoxidase activity were further parameters of pancreatic injury.. Remote preconditioning caused an improvement of microcirculation (functional capillary density: 1 hour after reperfusion, 460 +/- 13 vs 350 +/- 9 cm/cm2; 2 hours after reperfusion, 437 +/- 13 vs 295 +/- 13 cm/cm2; P < 0.01) and reduced inflammatory tissue response (leukocyte adherence in postcapillary venules: 2 hours after reperfusion, 155 +/- 55 vs 748 +/- 187 cells/mm2; P < 0.01). Histology was significantly better in preconditioned animals (IR, 8.1+/- 1.3 score points; RPC, 6.2 +/- 1.3 score points; P < 0.05). The difference in myeloperoxidase activity was not significant (ischemia/reperfusion [IR], 105 +/- 72; RPC, 245 +/- 209 mU x min(-1) x mg(ti)(-1); P = 0.13).. With our dynamic functional microcirculatory measurements, we could demonstrate that RPC is a feasible method to reduce experimental pancreatic IRI. This was seen in an attenuation of nutritive tissue perfusion and a reduction of inflammatory tissue response and a lower histological damage. Because it is easy to perform before organ harvest, RPC could be a step to improve organ procurement in pancreas transplantation. Clinical studies are the next step to evaluate RPC in pancreas transplantation.

Topics: Animals; Aorta; Capillaries; Cell Adhesion; Disease Models, Animal; Feasibility Studies; Hemodynamics; Ischemia; Ischemic Preconditioning; Leukocytes; Ligation; Male; Microscopy, Video; Pancreas; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Time Factors; Venules

Erythropoietin is traditionally known to regulate erythropoiesis, but recently its protective effect against ischemia-reperfusion injury has been studied in cardiovascular and neuronal systems. This study investigated the effect of recombinant human erythropoietin on ischemia-reperfusion injury in a rat transverse rectus abdominis musculocutaneous (TRAM) flap model.. Twenty-four Sprague-Dawley rats were divided into a control group (n = 12) and a group treated with erythropoietin (n = 12). A superiorly based TRAM flap was elevated and ischemic insult was given for 4 hours. Thirty minutes before reperfusion, single-dose recombinant human erythropoietin (5000 IU/kg) was injected through the intraperitoneal route in the treatment group. At 24 hours postoperatively, systemic neutrophil count, tissue myeloperoxidase activity, amount of malondialdehyde, nitric oxide content, tissue water content, and histologic finding of inflammation were evaluated. At day 10 postoperatively, flap survival rate, angiogenesis, and change in hematocrit level were evaluated.. The myeloperoxidase activity and tissue water content were significantly lower (p < 0.01 and p < 0.005, respectively), and the tissue nitric oxide level was significantly higher (p < 0.005) in the treatment group 24 hours after reperfusion. Perivascular neutrophil infiltration and intravascular adhesion were marked in the control group. Mean flap survival after 10 days was 69 percent in the treatment group and 47 percent in the control group, demonstrating a significant difference (p < 0.005). Neovascularization in the treatment group was also greater than that in the control group. No significant hematocrit rise was noted 10 days after erythropoietin administration.. Recombinant human erythropoietin improved flap survival in ischemia-reperfusion-injured rat TRAM flaps by the possible mechanism of suppressed inflammation, decreased infiltration of neutrophils, increased nitric oxide, and enhanced angiogenesis.

Topics: Animals; Apoptosis; Chemotaxis, Leukocyte; Drug Evaluation, Preclinical; Erythropoietin; Hematocrit; Humans; Inflammation; Malondialdehyde; Neovascularization, Physiologic; Neutrophils; Nitric Oxide; Peroxidase; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Rectus Abdominis; Reperfusion Injury; Surgical Flaps

To evaluate the effect of taurine, a potent antioxidant, on testicular ischemia-reperfusion injury due to excess reactive oxygen species produced by neutrophils after testicular torsion-detorsion.. A total of 60 adult male Sprague-Dawley rats were randomly divided into three groups, each containing 20 rats. The control group underwent a sham operation of the left testis. In the torsion-detorsion group, the left testis was rotated 720 degrees counterclockwise for 2 hours. The treatment group underwent the same surgical procedure as the torsion-detorsion group, but taurine was administered intravenously at repair of the testicular torsion. One half of the rats in each group underwent orchiectomy 4 hours after detorsion for measurement of myeloperoxidase activity, an indicator of neutrophil accumulation in the testis, and for evaluation of tissue malondialdehyde, an indicator of intratesticular reactive oxygen species content. The remainder were killed at orchiectomy 3 months after detorsion for analysis of testicular spermatogenesis.. Unilateral testicular torsion-detorsion caused a significant increase in myeloperoxidase activity and the malondialdehyde level and a significant decrease in testicular spermatogenesis in the ipsilateral testes. The decrease in ipsilateral testicular spermatogenesis involved a reduction in testicular weight, mean seminiferous tubular diameter, number of germ cell layers, and mean testicular biopsy score. The rats treated with taurine had a significant decrease in myeloperoxidase activity and malondialdehyde level and a significant increase in testicular spermatogenesis in the ipsilateral testes compared with the torsion-detorsion group.. The results of our study have shown that the administration of taurine exerts a beneficial effect on testicular ischemia-reperfusion injury. This effect might be partly the result of a reduction in reactive oxygen species generation by diminishing neutrophil recruitment to the testis.

Topics: Animals; Antioxidants; Biopsy; Germ Cells; Male; Malondialdehyde; Organ Size; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Seminiferous Tubules; Spermatic Cord Torsion; Spermatogenesis; Taurine; Testis

To investigate the feasibility of ex vivo adenovirus-mediated gene transfer of human interleukin10 (hIL10) via the pulmonary vein into lung isografts, and to investigate the effect of hIL-10 gene transfer on subsequent ischemia-reperfusion injury (IRI).. Fifty-six male SD rats were randomly divided into 4 equal groups: Group D, undergoing left lung isotransplantation with the improved cuff anastomosis technique (the Isografts were transvascularly transfected 5 ml of 5 x 10(9) plaque-forming units/ml adenovec-hIL-10 complex, Group C, with the Isografts transvascularly transfected with blank adenovirus vector Adenovec, Group B, with the Isografts transvascularly transfected with diluent , and Group A, undergoing sham operation. All allografts were preserved for 3 hours at 10 degrees C before transplantation. Four hours after reperfusion blood samples were collected from hr abdominal aorta to undergo blood air analysis. Lung function was evaluated by partial pressure of oxygen (PaO2). Then the rats were killed with their left lung taken out to undergo pathological examination. The graft lung wet-to-dry (W/D) weight ratio was measured. SABC immunohistochemistry was used to detect the expression of hIL-10 in the cytoplasm. ELISA was used to detect the expression of tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). The levels of malonyldialdehyde (MDA), superoxide dismutase (SOD), and myeloperoxidase (MPO) were measured by. Pathological morphologic change was also analyzed.. The PaO2 level of Group D was significantly higher than those of Groups B and C (both P < 0.01). The W/D ratio, and levels of MDA and MPO of Group D were significantly lower than those of Groups B and C (both P < 0.01), but the SOD level of Group D was significantly higher than those of Groups B and C (both P < 0.05). The TNF-alpha and IFN-gamma levels of Group D were significantly lower than those of Groups B and C (both P < 0.01). Fewer tissue edema and interstitial inflammation were found in lungs. Of Group D RT-PCR showed hIL-10 expression in the lungs of the rats of Group D, but not in other groups.. Ex vivo adenovirus-mediated gene transfer of hIL-10 via the pulmonary vein into the lung isografts is feasible and effective. hIL-10 gene transfer into lung isografts ameliorates subsequent IRI and improves early posttransplant graft function.

Topics: Adenoviridae; Animals; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Genetic Vectors; Humans; Interferon-gamma; Interleukin-10; Lung Transplantation; Male; Malondialdehyde; Peroxidase; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; Superoxide Dismutase; Transfection; Tumor Necrosis Factor-alpha

Oxidative stress occurs in remote liver injury, but the origin of the oxidant generation has yet to be thoroughly delineated. Some reports suggest that the source of the distant oxidative stress originates from the site of initial insult [i.e., xanthine oxidase (XO)]; however, it could also be derived from sources such as phagocytic and/or vascular NAD(P)H oxidase (Nox) enzymes. With a murine model of bilateral hindlimb ischemia-reperfusion, we describe here a mechanism for Nox-dependent oxidant production that contributes, at least in part, to remote hepatic parenchymal injury and sinusoidal endothelial cell (SEC) dysfunction. To determine whether Nox enzymes were the source of oxidants, mice were treated immediately after the onset of hindlimb ischemia with specific inhibitors to XO (50 mg/kg ip allopurinol) or Nox (10 mg/kg ip gp91ds-tat and 3 mg/kg ip apocynin). After 1 h of ischemia, hindlimbs were reperfused for either 3 or 6 h. Inhibition of XO failed to provide any improvement in parenchymal injury, SEC dysfunction, neutrophil accumulation, or microvascular dysfunction. In contrast, the inhibition of Nox enzymes prevented the progression (6 h) of parenchymal injury, significantly protected against SEC dysfunction, and completely prevented signs of neutrophil-derived oxidant stress. At the same time, however, inhibition of Nox failed to protect against the early parenchymal injury and microvascular dysfunction at 3 h of reperfusion. These data confirm that microvascular perfusion deficits are not essential for the pathogenesis of remote hepatic parenchymal injury. The data also suggest that Nox enzymes, not XO, are involved in the progression of compromised hepatic parenchymal and endothelial integrity during a systemic inflammatory response.

Topics: Animals; Disease Progression; Endothelium; Liver; Liver Diseases; Male; Mice; Mice, Inbred C57BL; Microcirculation; Models, Biological; NADPH Oxidases; Neutrophils; Oxidative Stress; Peroxidase; Reperfusion Injury; Tyrosine; Xanthine Oxidase

The peroxisome proliferator-activated receptor-alpha (PPAR-alpha) is a member of the nuclear receptor superfamily of ligand-dependent transcription factors related to retinoid, steroid, and thyroid hormone receptors. The aim of the present study was to examine the effects of endogenous PPAR-alpha ligand on the development of gut ischemia and reperfusion injury. Splanchnic artery occlusion (SAO) shock was induced in mice by clamping both the superior mesenteric artery and the celiac artery for 30 min, followed thereafter by release of the clamp (reperfusion). At 60 min after reperfusion, animals were sacrificed for histological examination and biochemical studies. SAO-shocked WT mice developed a significant increase of ileum tissue, TNF-alpha, IL-1beta, myeloperoxidase activity, and marked histological injury. SAO shock was also associated with a significant mortality (0% survival at 24 h after reperfusion). Reperfused ileum tissue sections from SAO-shocked WT mice showed positive staining for P-selectin, ICAM-1, TNF-alpha, and IL-1beta. Absence of a functional PPAR-alpha gene in PPAR-alphaKO mice resulted in a significant augmentation of all the above-described parameters. Thus, endogenous PPAR-alpha ligands reduce the degree of ileum injury caused by ischemia and reperfusion.

Topics: Animals; Ileum; Interleukin-1; Ligands; Mice; Mice, Knockout; Peroxidase; PPAR alpha; Reperfusion Injury; Shock; Tumor Necrosis Factor-alpha

The mechanisms involved in renal ischemia-reperfusion injury (IRI) are complex and appear to involve the early participation of bone marrow-derived cells. T lymphocytes participate in the pathogenesis of IRI. Sphingosine 1-phosphate (S1P) induces peripheral T cell depletion. Therefore, we hypothesized that S1P1 receptor activation protects kidney from IRI. FTY-720, a non-receptor-selective sphingosine analog, was given intraperitoneally to C57BL/6 mice, and animals were subjected to ischemia for 32 min followed by reperfusion for 24 h. Plasma creatinine, blood count, myeloperoxidase (MPO) activity, and renal histology were determined. IRI led to a marked increase in plasma creatinine, MPO activity, leukocyte infiltration, and vascular permeability. FTY-720 significantly decreased plasma creatinine in a dose-response manner with a maximal reduction of approximately 73 and approximately 69% with doses of 240 and 48 microg/kg, respectively. MPO, leukocyte infiltration, vascular permeability, and peripheral blood lymphocyte counts were markedly decreased with FTY-720 treatment. The protective effect of FTY-720 was reversed with VPC-44116, a selective S1P1 receptor antagonist. Furthermore, SEW-2871, a selective S1P1 agonist, significantly decreased plasma creatinine in a dose-response manner with a maximal reduction of approximately 70% with a dose of 10 mg/kg. Analysis of kidneys by light microscopy revealed minimal histological signs of ischemic injury with FTY-720 or SEW-2871 treatment compared with the vehicle group. Using RT-PCR, we found a time-dependent increase in the S1P1 mRNA expression following IRI that begins after 2 h with the maximum expression at approximately 4 h. We conclude that the protective effect of FTY-720 is due primarily to activation of S1P1 receptors. The mechanism of protection is not known but may be related to peripheral lymphocyte depletion or direct effects on kidney cells expressing S1P1 receptor.

Topics: Animals; Capillary Permeability; Creatinine; Fingolimod Hydrochloride; Kidney; Leukocytes; Lymphocyte Count; Mice; Mice, Inbred C57BL; Oxadiazoles; Peroxidase; Propylene Glycols; Receptors, Lysosphingolipid; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sphingosine; T-Lymphocytes; Thiophenes

Ischemia-reperfusion injury induces a systemic inflammatory response and production of reactive oxygen species, which potentially can be more detrimental than its local effects. Although the lung injury that is formed by the effects of ischemia-reperfusion injury on remote organs has been previously studied, no previous study that investigated the effects of pulmonary ischemia-reperfusion injury on remote organs has been considered. We hypothesized that the lung ischemia-reperfusion injury may cause the spread of inflammation to remote organs such as liver and heart.. Thirty New Zealand white rabbits were subjected to either sham operation or lung ischemia-reperfusion injury in various periods of time (60 min ischemia-60 min reperfusion and 120 min ischemia-60 min reperfusion, respectively). Pulmonary, myocardial and hepatic myeloperoxidase, protein sulfhydryl, thiobarbituric acid-reactive substances, and protein carbonyl levels were evaluated to show pulmonary, hepatic, and myocardial responses to lung ischemia-reperfusion injury.. Reperfusion after 60 min of lung ischemia led to increased myeloperoxidase and protein carbonyl levels and decreased protein sulfhydryl groups in pulmonary tissue, increased myeloperoxidase and decreased protein sulfhydryl groups in hepatic tissue, and increased myeloperoxidase, thiobarbituric acid-reactive substances and protein carbonyl levels in myocardial tissue. Reperfusion after 120 min of lung ischemia led to increased thiobarbituric acid-reactive substance levels in pulmonary tissue, increased protein carbonyl and thiobarbituric acid-reactive substance levels in hepatic tissue, and decreased protein sulfhydryl groups in myocardial tissue.. The data of the present study suggests that pulmonary ischemia-reperfusion induces liver and heart injury characterized by activated neutrophil sequestration and release of significant amounts of reactive oxygen species. The remote organ injury has to be kept in mind when performing a lung intervention or surgery and care should be taken to protect other organs remote from ischemia-reperfusion site.

Topics: Animals; Lipid Peroxidation; Liver; Lung; Myocardial Reperfusion Injury; Neutrophil Activation; Oxidative Stress; Peroxidase; Protein Carbonylation; Rabbits; Random Allocation; Reactive Oxygen Species; Reperfusion Injury

Restoring intracellular cGMP and inducing NO-synthesis attenuates ischemia-associated early pulmonary allograft dysfunction. Phosphodiesterase-5 (PDE), predominantly expressed in lung tissue, plays a pivotal role in modulating the cGMP/NO-synthase pathway in endothelial and epithelial cells. In this study, we evaluate the effect of employing sildenafil (Viagra), a specific inhibitor of PDE-5, to counteract ischemia/reperfusion (I/R) injury in a single lung transplantation model of extended ischemia.. Donor animals (weight matched outbred pigs, 28-35 kg) in the treatment group (I) (n=5) were injected with 0.7 mg sildenafil/kg into the pulmonary artery (PA) prior to inflow occlusion. For perfusion, Perfadex, containing 0.7 mg sildenafil/l was used, and the graft stored at 1 degrees C in the perfusion solution. After 24h ischemia, unilateral left lung transplantation was performed. Starting at reperfusion, group I received continuous sildenafil (0.7 mg sildenafil/kg), over 6h. Except for the sildenafil application, the control group (II) (n=4) was treated identically (PGE1 was injected into the PA). One hour after reperfusion, the right main bronchus (MB) and right PA were occluded. Over the next 5h, cardiopulmonary parameters (systemic atrial, PA, central venous, left atrial pressure, pCO(2), pO(2)) were measured, including extravascular lung water (EVLW). Thiobarbituric acid-reactive substance assay (TBARS) and myeloperoxidase (MPO) analysis from lung tissue were run.. All recipients of group I survived the 6-h reperfusion period; in contrast, all control animals died within 1-2h after occlusion of the right side. In comparison to a marked rise in pulmonary vascular resistance (PVR) in group II (>1000 dynescm(-5)), PVR in group I remained stable, moderately elevated from baseline (baseline: 150-180 dynescm(-5) vs endpoint: 1000 dynescm(-5)). EVLW in group I did not increase during reperfusion (baseline: 6.75+/-1.4 mg/kg vs endpoint: 6.7+/-1.0mg/kg), in contrast to group II, where pulmonary edema at 2-h reperfusion preceded terminal graft failure (group I: 9.7+/-0.1mg/kg vs group II: 6.48+/-1.8 mg/kg). Tissue reactive free radicals at endpoint measurement in group I did not differ significantly from native tissue. Yet, when compared to specimen taken from group II at time of terminal graft failure, a significant increase in free radicals was noted (group I: 13.8+/-1.6 pmol/g vs group II: 18.5+/-3.0 pmol/g, p<0.05).. Sildenafil treatment prevents terminal early graft failure, allowing lung transplantation after 24-h ischemia time. Reperfusion edema was strikingly diminished, preserving pulmonary structural and functional integrity while prolonging graft ischemia time. Employing the established PDE-5 inhibitor sildenafil during lung perfusion, storage, and implantation, ischemic tolerance may be extended and early graft function improved.

Topics: 3',5'-Cyclic-GMP Phosphodiesterases; Animals; Cyclic Nucleotide Phosphodiesterases, Type 5; Disease Models, Animal; Drug Evaluation, Preclinical; Extravascular Lung Water; Graft Survival; Lipid Peroxidation; Lung Transplantation; Peroxidase; Phosphodiesterase Inhibitors; Phosphoric Diester Hydrolases; Piperazines; Pulmonary Circulation; Purines; Reperfusion Injury; Sildenafil Citrate; Sulfones; Swine; Vascular Resistance

Hepatic injury caused by ischemia/reperfusion (I/R) is a key clinical problem associated with liver transplantation and liver surgery. The spleen is involved in hepatic I/R injury. In this study, we examined the effects of splenic artery ligation on hepatic I/R injury.. Splenic artery ligation was performed 7 days, 3 days, or just before the hepatic ischemia. Hepatic ischemia was conducted by occluding the blood vessels to the median and left lateral lobes with an atraumatic vascular clamp. Hepatic I/R injury was induced by 45 min of ischemia followed by 120 min of reperfusion.. When splenic artery ligation was performed at 3 days or just before the ischemia, serum aspartate transaminase and alanine transaminase activities, as markers for hepatic injury, decreased as compared with the rats with I/R alone. Splenic artery ligation also reduced the myeloperoxidase activity, an enzyme present in neutrophils, and the expression of interleukin-6 mRNA, a proinflammatory cytokine, in rat livers with I/R. Efficacy of splenic artery ligation on hepatic I/R injury was also confirmed by histology. On the other hand, when splenic artery ligation was conducted 7 days before the ischemia, efficacy of splenic artery ligation was disappeared.. Splenic artery ligation ameliorates hepatic I/R injury in rats. These results strongly suggest the clinical usefulness of this surgical procedure to protect the liver against I/R injury.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Biomarkers; Disease Models, Animal; Embolization, Therapeutic; Interleukin-6; Ligation; Male; Neutrophils; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; RNA, Messenger; Splenic Artery

Activation of extravascular coagulation has been reported in acute lung injury models of sepsis and acute respiratory distress syndrome. Thrombin, the main effector protease of extravascular coagulation, activates proinflammatory cell types, including macrophages, endothelial cells, and neutrophils, each of which participates in lung ischemia-reperfusion injury. We used hirudin, a potent, specific direct thrombin inhibitor, to define the role of thrombin in lung ischemia-reperfusion injury.. Rats were pretreated with hirudin 30 minutes before warm, in situ left lung ischemia and reperfusion. Multiple in vivo assessments of lung injury were determined, and mechanistic studies assessed transcriptional regulation early in reperfusion and proinflammatory protein secretion late in reperfusion. Immunohistochemistry localized thrombin activation.. Thrombin localized to macrophages and endothelial and epithelial cells early in reperfusion. Hirudin significantly limited lung ischemia-reperfusion injury-induced derangements in vascular permeability and intraalveolar inflammatory cell sequestration, resulting in improved arterial oxygenation after ischemia and 4 hours of reperfusion. The protection was transcriptionally mediated by attenuated activator protein-1 and early growth response-1 transactivation, but not nuclear factor kappa B transactivation. This was associated with reduced chemokine, but not tumor necrosis factor alpha, secretion late in reperfusion.. Thrombin promotes lung ischemia-reperfusion injury, as hirudin protected against experimental acute lung injury. Hirudin conferred protection through a mechanism independent of nuclear factor kappa B and tumor necrosis factor alpha, suggesting that its effects may be mediated by a parallel, synergistic inflammatory pathway through activator protein-1 and early growth response-1.

Topics: Animals; Capillary Permeability; Disease Models, Animal; Humans; Inflammation; Ischemia; Peroxidase; Pulmonary Circulation; Rats; Rats, Long-Evans; Reperfusion; Reperfusion Injury; Respiratory Function Tests; Thrombosis

Gradually increased blood flow to the ischemic rat kidney was studied to assess the ability to diminish ischemia-reperfusion injury.. The left renal artery and vein were isolated in 25 rats. Microclamps were applied for 45 minutes and were released at once (group II) or gradually (group III). Renal arterial blood flow and K+ activity were measured. Bilateral kidneys were harvested for histopathology and for malonyldealdehyde and myeloperoxidase levels.. Increased K+ activity returned to preischemic values faster in group III than in group II. No statistically significant difference existed in malonyldealdehyde and myeloperoxidase levels; histopathologic scoring showed less tissue damage in group III (P < .05). Contralateral kidney samples showed signs of ischemia in group II.. Gradually increased blood flow to the ischemic kidney decreases ischemic changes. Ischemic insult to 1 kidney causes histopathologically detectable changes to the contralateral kidney, which can be diminished by gradual reperfusion.

Topics: Analysis of Variance; Animals; Kidney; Kidney Transplantation; Male; Malondialdehyde; Peroxidase; Potassium; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion; Reperfusion Injury

Pressure ulcers (PU) cause morphological and functional alterations in the skin and visceral organs; the damage is believed to be due to ischemia/reperfusion (I/R) injury. In this study, we examined the role of oxidative damage in PU and the beneficial effect of treatment with the antioxidant melatonin. PU were induced by applying magnets over steel plates that were implanted under the skin of rats; this compressed the skin and caused ischemia. Within a 12-hr period, rats were subjected to five cycles of I/R (2 and 0.5 hr respectively), followed by an additional 12 hr of ischemia (to simulate the period at sleep at night). This protocol was repeated for 3 days. In treatment groups, twice a day during reperfusion periods, melatonin (5 mg per rat) was either applied locally as an ointment on skin, or administered i.p. (10 mg/kg). At the end of the experimental period, blood and tissue (skin, liver, kidney, lung, stomach, and ileum) samples were taken for determination of biochemical parameters and for histological evaluation. Local treatment with melatonin inhibited the increase in malondialdehyde levels; an index of lipid peroxidation, myeloperoxidase activity; an indicator of tissue neutrophil infiltration, and the decrease in glutathione; a key antioxidant, in the skin induced by PU, but was less efficient in preventing the damage in visceral organs. However, systemic treatment prevented the damage in the visceral organs. Significant increases in creatinine, blood urea nitrogen, alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and collagen levels in animals with PU were prevented by melatonin treatment. The light microscopic examination exhibited significant degenerative changes in dermis and epidermis in the PU rats. Tissue injury was decreased especially in the locally treated group. Findings of the present study suggest that local and/or systemic melatonin treatment may prove beneficial in the treatment of PU.

Topics: Administration, Topical; Alanine Transaminase; Animals; Aspartate Aminotransferases; Blood Urea Nitrogen; Creatine; Female; Glutathione; Injections, Intraperitoneal; Kidney Diseases; L-Lactate Dehydrogenase; Lipid Peroxidation; Liver Diseases; Magnetics; Male; Malondialdehyde; Melatonin; Peroxidase; Pressure Ulcer; Rats; Rats, Wistar; Reperfusion Injury; Skin

The aim of the study was to investigate the impact of ischemia/reperfusion injury on the proteome of Kupffer cells. Lean Zucker rats (n = 6 each group) were randomized to 75 min of warm ischemia or sham operation. After reperfusion for 8 h, Kupffer cells were isolated by enzymatic perfusion and density gradient centrifugation. Proteins were tryptically digested into peptides and differentially labeled with iTRAQ (isobaric tags for relative and absolute quantitation) reagent. After fractionation by cation exchange chromatography, peptides were identified by mass spectrometry (ESI-LC-MS/MS). Spectra were interrogated against the Swiss-Prot database and quantified using ProteinProspector. The results for heat shock protein 70 and myeloperoxidase were validated by ELISA. Quantitative information for more than 1559 proteins was obtained. In the ischemia group proteins involved in inflammation were significantly up-regulated. The ratio for calgranulin B in the ischemia/sham group was 1.81 +/- 0.97 (p < 0.0001), for complement C3 the ratio was 1.81 +/- 0.49 (p < 0.0001), and for myeloperoxidase the ratio was 1.30 +/- 0.32. Myeloperoxidase was only recently documented in Kupffer cells. The antioxidative proteins Cu,Zn-superoxide dismutase (1.34 +/- 0.19; p < 0.001) and catalase (1.23 +/- 0.43; p < 0.001) were also elevated. In conclusion, ischemia/reperfusion injury induces alterations in the Kupffer cell proteome. Isotope ratio mass spectrometry is a powerful tool to investigate these reactions. The ability to simultaneously monitor several pathways involved in reperfusion stress may result in important mechanistic insight and possibly new treatment options.

Topics: Animals; Calcium-Binding Proteins; Calgranulin B; Complement C3; Glutathione Transferase; HSP70 Heat-Shock Proteins; Kupffer Cells; Liver; Microfilament Proteins; Models, Animal; Peroxidase; Peroxidases; Peroxiredoxins; Proteomics; Rats; Rats, Zucker; Reperfusion Injury; Spectrometry, Mass, Electrospray Ionization; Superoxide Dismutase

To determine whether two episodes of acute urinary retention lead to additional ischemia-reperfusion injury due to decompression of the bladder, or not.. Sham, retention and recurrent retention groups consisting of 5, 8 and 8 Wistar Albino male rats were randomized, respectively. After the bladders of rats were emptied with 3F catheter, penile urethras were clamped with aneurism clamp and waited for 30 min after diuresis was forced. At the end of this period, penile clamps were removed and the bladder was again decompressed with 3F catheter and after 30 min removed for examination. In the recurrent retention group, the same process was repeated after an interval of one week. Malonedialdehyde (MDA) levels, indicator of lipid peroxidation and myeloperoxidase (MPO) levels, indicator of leukocyte activation, were examined biochemically in the tissues of the removed bladders.. In the retention and recurrent retention groups, the average increase in bladder MDA and MPO values was higher than the values of sham group (P < 0.05), however, no significant difference was determined between retention and recurrent retention groups (P > 0.05).. In the bladder tissue, due to acute urinary retention and following decompression process, ischemia-reperfusion injury occurs. Two episodes of acute urinary retention do not lead to additional the ischemia-reperfusion injury that develops in the bladder.

Topics: Animals; Decompression, Surgical; Disease Models, Animal; Male; Malondialdehyde; Peroxidase; Rats; Rats, Wistar; Recurrence; Reperfusion Injury; Urinary Retention

Nitric oxide (NO) involvement in intestinal ischemia-reperfusion (I/R) injury has been widely suggested but its protective or detrimental role remains still question of debate. Here, we examine the impact of supplementation or inhibition of NO availability on intestinal dysmotility and inflammation caused by mesenteric I/R in mice. Ischemia 45min and reperfusion 24h were performed by superior mesenteric artery occlusion in female Swiss mice. Saline-treated sham-operated (S) or normal mice without surgery (N) served as controls. Drugs were subcutaneously injected 0, 4, 8, and 18 h after ischemia. Upper gastrointestinal transit (GIT, estimated through black marker gavage), intestinal myeloperoxidase activity (MPO), intestinal malondialdehyde levels (MDA), Evans blue extravasation (EB), intestinal histological damage, and mean arterial pressure (MAP) were considered. In I/R mice, GIT was significantly delayed compared to S and N groups; MPO activity and EB extravasation enhanced, whereas MDA levels did not change. Compared to N and S groups, in I/R mice selective iNOS inhibitor P-BIT significantly prevented motor, MPO and EB changes; putative iNOS inhibitor aminoguanidine significantly counteracted GIT delay but not neutrophil recruitment and the increase in vascular permeability; NOS inhibitor l-NAME and NO precursor l-arginine were scarcely or no effective. Furthermore, in S mice aminoguanidine caused a significant increase of MPO activity reverted by H(1) histamine receptor antagonist pre-treatment. Unlike P-BIT, aminoguanidine and l-NAME injection increased MAP. These findings confirm a detrimental role for iNOS-derived NO overproduction during reperfusion. Aminoguanidine-associated neutrophil recruitment suggests that this drug could act through mechanisms additional to iNOS inhibition involving both eNOS blockade, as indicated by its hemodynamic effects, and indirect activation of H(1) histamine receptors.

Topics: Animals; Blood Pressure; Enzyme Inhibitors; Female; Gastrointestinal Transit; Guanidines; Intestine, Small; Malondialdehyde; Mice; Mice, Inbred Strains; NG-Nitroarginine Methyl Ester; Nitric Oxide Synthase Type II; Peroxidase; Reperfusion Injury; Thiourea

To investigate the effects of propofol and caffeic acid phenethyl ester (CAPE) on prevention of lung injury as a remote organ after performing hindlimb ischaemia-reperfusion (IR) in a rat model.. The animals were divided randomly into one of four groups: sham, no IR (n = 8), control, IR, (n = 8), CAPE group, IR with CAPE, (n = 8), propofol group, IR with P, (n = 8). After the rats were anaesthetised, the animals in the CAPE group received CAPE of 10 micromol, in the propofol group received propofol 50 mg/kg, in the control group received a similar volume of saline solution by means of intraperitoneal injection 1 h before reperfusion. After 4 h of ischaemia the tourniquet was removed and the animals were released for reperfusion for 4 h thereafter. At the end of the reperfusion period, a median sternotomy was performed. A blood sample was obtained for plasma malondialdehyde (MDA). The lung tissues were also removed for MDA assays, myeloperoxidase (MPO) activity, and histopathological examination.. Plasma and lung MDA levels, and lung MPO activity were significantly higher in the control group compared to the other groups (p < 0.0005). In the CAPE group, these were significantly lower compared to the control group (p < 0.0005). Also, propofol caused a marked reduction in the MDA levels and MPO activity compared with control group (p < 0.0005), with no significant difference compared to that of the sham group. Histopathologically, the scores resulted in a grade zero (8/8) in the sham group, 3 (3/8) or 4 (5/8) in the control group, 1 (2/8) or 2 (6/8) in the CAPE group, and 1 (3/8) or 2 (5/8) in the propofol group.. Propofol and CAPE seem to be effective in protecting against lung injury caused by increased oxidative stress and neutrophil accumulation after hindlimb IR in a rat model.

Topics: Animals; Caffeic Acids; Free Radical Scavengers; Hindlimb; Ischemia; Lung; Lung Diseases; Male; Malondialdehyde; Oxidative Stress; Peroxidase; Phenylethyl Alcohol; Positive-Pressure Respiration; Propofol; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Treatment Outcome

Ischemia is a transitory or permanent reduction of blood flow that may provoke an excessive release of glutamate. In that condition, increased reactive oxygen species generation and/or decreased cerebral antioxidant capacity may induce cell death. Antioxidant enzymes and thiols play an important role in the cellular defenses against oxidative stress. The purpose of this study was to evaluate cell viability, glutamate uptake and antioxidant status in rat hippocampal slices exposed to oxygen-glucose deprivation (OGD), an in vitro model of ischemia. After 15 min or 1 h of OGD, hippocampal slices showed a significant reduction of cell viability. Reperfusion during 1 or 2 h did not increase cell death. In this condition, the activities of antioxidant enzymes catalase, glutathione reductase, and peroxidase did not change. However, slices exposed to 15 min OGD and reperfused for 1 or 2 h showed higher superoxide dismutase activity. A significant reduction of glutathione levels was observed after 1 or 2 h of reperfusion in slices previously exposed to 1 h of OGD, although the protein-thiol content was unchanged. Slices exposed to 1 h of OGD and reperfused for 2 h showed reduced sodium-dependent l-[(3)H]glutamate uptake. The reduction of glutamate uptake was partially reversed by dl-dithiothreitol (DTT), a thiol-reducing agent, which may reduce thiol groups in glutamate transporters. Therefore, higher glutamate levels in the synaptic cleft could promote transporter reversal and impair glutamate uptake. Increased extracellular glutamate levels associated with decreased glutathione levels might exacerbate cell damage induced by oxygen and glucose deprivation.

Topics: Amino Acid Transport System X-AG; Animals; Antioxidants; Catalase; Cell Survival; Dithiothreitol; Down-Regulation; Glutamic Acid; Glutathione; Glutathione Reductase; Hippocampus; Hypoxia-Ischemia, Brain; Male; Organ Culture Techniques; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase; Synaptic Membranes; Synaptic Transmission

Angiotensin II has been implicated in the pathogenesis of vascular inflammation in various organs. The aim of the present study was to examine the effect of angiotensin II type I receptor antagonist, CV-11974, on reperfusion-induced small intestinal injury in rats.. Intestinal damage was induced by clamping both the superior mesenteric artery and the celiac trunk for 30 min followed by reperfusion for 60 min in male Wistar rats. CV-11974 was given to the rats by intravenous injection 1 h before the vascular clamping. The intestinal mucosal injury and inflammation were evaluated by biochemical markers and histological findings. Thiobarbituric acid reactive substances and tissue-associated myeloperoxidase (MPO) activity were measured in the gastric mucosa as indices of lipid peroxidation and neutrophil infiltration. The expressions of pro-inflammatory cytokines (CINC-1) in intestinal mucosa were measured by enzyme-linked immunosorbent assay (ELISA) and reverse transcription-PCR (RT-PCR). In additional experiments with an in vitro flow system, human neutrophils were perfused on human umbilical vein endothelial cells (HUVEC) pretreated with anoxia-reoxygenation with or without CV-11974 and then the adhesive neutrophils were counted.. Reperfusion after ischemia resulted in an increase in luminal protein concentrations, hemoglobin concentrations, thiobarbituric acid reactive substances, and MPO activity. Pretreatment with CV-11974 significantly inhibited the increases in these parameters. CV-11974 also inhibited increases in intestinal CINC-1 protein and mRNA expression induced by ischemia-reperfusion. Moreover, in an in vitro study, CV-11974 significantly inhibited the adherence of neutrophils to HUVEC exposed to reoxygenation after anoxia.. These results suggest that the blockade of angiotensin II type I receptor by treatment with CV-11974 remarkably reduced the reperfusion-induced intestinal injury.

Topics: Angiotensin II Type 1 Receptor Blockers; Animals; Benzimidazoles; Biphenyl Compounds; Cell Adhesion; Cell Line; Chemokine CXCL1; Chemokines, CXC; Dose-Response Relationship, Drug; Endothelial Cells; Gene Expression; Hemoglobins; Humans; Intestinal Diseases; Intestinal Mucosa; Intestine, Small; Male; Neutrophils; Peroxidase; Proteins; Rats; Rats, Wistar; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Tetrazoles; Thiobarbituric Acid Reactive Substances

Pressure ulcers (PU) cause morphological and functional alterations in the skin and visceral organs. In this study we investigated the role of oxidative damage in PUs and the probable beneficial effect of beta-glucan treatment against this damage. beta-glucan is known to have immunomodulatory effects. Experiments were carried on Wistar albino rats. PU was induced by applying magnets over steel plates that were implanted under the skin, to compress the skin and cause ischemia where removing the magnets cause reperfusion of the tissue. Within the first 12 h, rats were subjected to 5 cycles of ischemia/reperfusion (I/R), followed by 12 h ischemia. This protocol was repeated for 3 days. In treatment groups, twice a day during reperfusion periods, beta-glucan was either applied locally (25 mg/kg) as an ointment on skin, or administered orally (50 mg/kg) as a gavage. At the end of the experimental periods, tissue samples (skin, liver, kidney, lung, stomach, and ileum) were taken for the measurement of malondialdehyde (MDA)--an index of lipid peroxidation--and glutathione (GSH)--a key antioxidant--levels. Neutrophil infiltration was evaluated by the measurement of tissue myeloperoxidase activity, while collagen contents were measured for the evaluation of tissue fibrosis. Skin tissues were also examined microscopically. Liver and kidney functions were assayed in serum samples. Local treatment with beta-glucan inhibited the increase in MDA and MPO levels and the decrease in GSH in the skin induced by PU, but was less efficient in preventing the damage in visceral organs. However, systemic treatment prevented the damage in the visceral organs. Significant increases in creatinine, BUN, ALT, AST, LDH and collagen levels in PU group were prevented by beta-glucan treatment. The light microscopic examination exhibited significant degenerative changes in dermis and epidermis in the PU group. Tissue injury was decreased especially in the locally treated group. Thus, supplementing geriatric and neurologically impaired patients with adjuvant therapy of beta-glucan may have some benefits for successful therapy and improving quality of life.

Topics: Administration, Oral; Administration, Topical; Alanine Transaminase; Animals; Antioxidants; beta-Glucans; Collagen; Female; Gastric Mucosa; Glutathione; Ileum; Kidney; Lung; Male; Malondialdehyde; Neutrophil Infiltration; Oxidative Stress; Peroxidase; Pressure Ulcer; Rats; Rats, Wistar; Reperfusion Injury; Skin; Stomach

Oxygen free radicals are important components involved in the pathophysiological processes observed during ischemia/reperfusion (I/R).. This study was designed to assess the possible protective effect of montelukast, a selective antagonist of cysteinyl leukotriene receptor 1 (CysLT1), on renal I/R injury.. Wistar albino rats were unilaterally nephrectomized and subjected to 45 min of renal pedicle occlusion followed by 6 h of reperfusion. Montelukast (10 mgkg(-1), i.p.) or saline was administered at 15 min prior to ischemia and immediately before the reperfusion period. At the end of the reperfusion period, following decapitation, kidney samples were taken for histological examination or for determination of renal malondialdehyde (MDA), an end product of lipid peroxidation; glutathione (GSH), a key antioxidant; and myeloperoxidase (MPO) activity, an index of tissue neutrophil infiltration. Formation of reactive oxygen species in renal tissue samples was monitored by using chemiluminescence (CL) technique with luminol and lucigenin probes. Creatinine, blood urea nitrogen and lactate dehydrogenase (LDH) activity were measured in the serum samples, while leukotriene B4, TNF-alpha, IL-beta, IL-6 and total antioxidant capacity (AOC) were assayed in plasma samples.. Ischemia/reperfusion caused a significant decrease in renal GSH and plasma AOC, which was accompanied with significant increases in MDA level, MPO activity, and CL levels of the renal tissue concomitant with increased levels of the pro-inflammatory mediators, LDH activity, creatinine and BUN. On the other hand, montelukast treatment reversed all these biochemical indices as well as histopathological alterations induced by I/R.. CysLT1 receptor antagonist montelukast reversed I/R-induced oxidant responses, improved microscopic damage and renal function. It seems likely that montelukast protects kidney tissue by inhibiting neutrophil infiltration, balancing oxidant-antioxidant status, and regulating the generation of inflammatory mediators.

Topics: Acetates; Animals; Blood Urea Nitrogen; Creatinine; Cyclopropanes; Glutathione; Interleukin-1; Interleukin-6; Kidney; L-Lactate Dehydrogenase; Leukotriene Antagonists; Leukotriene B4; Male; Malondialdehyde; Neutrophil Infiltration; Peroxidase; Quinolines; Rats; Rats, Wistar; Reperfusion Injury; Sulfides; Tumor Necrosis Factor-alpha

To evaluate the combined effect of alpha-tocopherol and gadolinium chloride (GdCl3) in reducing lipid peroxidation after severe hepatic ischemia/reperfusion (IR) injury.. Sixty male Wistar rats, 200-250 g, were randomly divided into six equal groups. There were two sham operation (SHAM) groups, two untreated IR groups, and two IR groups treated with GdCl3 and alpha-tocopherol (IRGT). After 60 min of total hepatic ischemia and 120 min reperfusion, one of each group was killed, liver samples were taken for malondialdehyde (MDA) and myeloperoxidase (MPO) analysis and light microscopy examination, and blood samples were analyzed for aspartate (AST) and alanine (ALT) transaminase, lactate dehydrogenase (LDH), and alpha-tocopherol content. The remaining groups were monitored for survival rate determination.. The mean MDA and MPO values in the SHAM, IR, and IRGT groups, respectively, were 1.117, 1.476, and 0.978 nmol/g wet tissue and 1.49, 6.26, and 1.78 (U/g). The mean alpha-tocopherol values in the SHAM, IR, and IRGT groups, respectively, were 10.4, 1.9, and 12 micromol/l. The mean serum AST, ALT, and LDH values were significantly higher in the IR group than in the SHAM group (P < 0.001), and significantly lower in the IRGT group than in the IR group (P < 0.001). Light microscopy examination revealed more severe congestion and vacuolization in the IR group than in the SHAM group, and minimal congestion and vacuolization in the IRGT group. Survival was significantly higher in the IRGT group than in the IR group.. The administration of GdCl3 and alpha-tocopherol is likely to protect the liver against lipid peroxidation by suppressing Kupffer cell and polymorphonuclear leukocyte activation and enhancing endogenous antioxidant activity.

Topics: alpha-Tocopherol; Animals; Gadolinium; Kupffer Cells; Lipid Peroxidation; Liver; Liver Circulation; Liver Function Tests; Male; Malondialdehyde; Peroxidase; Protective Agents; Random Allocation; Rats; Rats, Wistar; Reperfusion Injury

To examine whether dalteparin, a low molecular weight heparin, prevents hepatic damage by inhibiting leukocyte activation, we analyzed its effect on ischemia/reperfusion (I/R) injury of rat liver in which activated leukocytes play a critical role.. Prospective, randomized, controlled study.. Research laboratory at a university medical center.. Male Wistar rats weighing 220-280 g.. Hepatic damage was evaluated by changes in serum transaminase concentrations after I/R. Coagulation abnormalities were evaluated by changes in serum concentrations of fragment E of fibrin and fibrinogen degradation products after I/R. Hepatic tissue blood flow was measured by laser-Doppler flow meter. Hepatic edema was evaluated by determination of the change in the wet/dry tissue weight ratio. Rats were intravenously injected with dalteparin or unfractionated heparin (300 units/kg) and subcutaneously injected with DX9056a, a selective inhibitor of activated factor X (3 mg/kg). To determine whether dalteparin inhibits leukocyte activation, we examined the effect of dalteparin on hepatic concentrations of interleukin-12, tumor necrosis factor-alpha, and hepatic myeloperoxidase activity after I/R in vivo. In addition, we examined increases in tumor necrosis factor-alpha production in rat monocytes and in intracellular calcium concentrations in neutrophils in vitro. We also examined the effect of dalteparin on endothelial production of prostacyclin using isolated rat hepatic sinusoidal cells in vitro.. Intravenous administration of dalteparin inhibited increases in serum levels of both transaminases and serum concentrations of fragment E of fibrin and fibrinogen degradation products in animals subjected to hepatic I/R. Hepatic tissue blood flow after reperfusion was increased by dalteparin. Dalteparin inhibited hepatic edema, increases in hepatic tissue levels of interleukin-12 and tumor necrosis factor-alpha, and accumulation of neutrophils in animals subjected to hepatic I/R. Neither DX9065a nor unfractionated heparin showed any therapeutic effects, despite potent inhibition of increases in serum levels of fragment E of fibrin and fibrinogen degradation products. Neither monocytic tumor necrosis factor-alpha production nor neutrophil activation was inhibited by dalteparin in vitro. Dalteparin enhanced the hepatic I/R-induced increases in hepatic tissue levels of 6-keto-prostaglandin (PG) F1alpha, a stable metabolite of prostacyclin, which is capable of inhibiting monocytic tumor necrosis factor-alpha production. Pretreatment with indomethacin completely reversed both of the therapeutic effects of dalteparin, whereas pretreatment with NS-398, a selective inhibitor of cyclooxygenase-2, did not. Dalteparin did not directly increase the endothelial production of prostacyclin in vitro.. Dalteparin might reduce I/R-induced liver injury in rats by attenuating inflammatory responses. These therapeutic effects might be independent of its anticoagulant activity but dependent on its capacity to enhance endothelial production of prostacyclin via cyclooxygenase-1 activation. Furthermore, the mechanism or mechanisms by which dalteparin promotes the endothelial production of prostacyclin in vivo might involve unknown factors other than endothelial cells.

Topics: 6-Ketoprostaglandin F1 alpha; Animals; Anticoagulants; Calcium; Cyclooxygenase 2 Inhibitors; Dalteparin; Edema; Endothelium; Epoprostenol; Fibrin Fibrinogen Degradation Products; Heparin; In Vitro Techniques; Indomethacin; Inflammation; Interleukin-12; Leukocytes; Liver; Liver Diseases; Male; Monocytes; Naphthalenes; Nitrobenzenes; Peroxidase; Propionates; Prospective Studies; Random Allocation; Rats; Rats, Wistar; Reperfusion Injury; Sulfonamides; Transaminases; Tumor Necrosis Factor-alpha

Based on the findings that erythropoietin (EPO) has been proved to be a multiple functional cytokine to attenuate ischemia-reperfusion (I/R) injury in various organs such as brain, heart, and kidney in animals, this experiment was designed to evaluate the effect of pretreatment with recombined human erythropoietin (rhEPO) on I/R-induced lung injury.. Left lungs of rats underwent 90 min of ischemia and then were reperfused for up to 2 h. Animals were randomly divided into three experimental groups as sham group, I/R group, and rhEPO + I/R group (a single dose of rhEPO was injected intraperitoneally 3000 U/kg 24 h prior to operation). Lung injury was evaluated according to semi-quantitative analysis of microscopic changes, tissue polymorphonuclear neutrophils (PMNs) accumulation (myeloperoxidase (MPO) activity), and pulmonary microvascular permeability (Evan's blue dying method). Peripheral arterial and venous blood samples were obtained for blood-gas analysis after 5 min occlusion of right lung hilus at the end of reperfusion. The serum concentration of tumor necrosis factor (TNF)-alpha was also measured by the method of enzyme-linked immunosorbent assay.. Histological injury scoring revealed significantly lessened lung alveolus edema and neutrophils infiltration in the rhEPO pretreated group compared with I/R group (p < 0.05). The rhEPO pretreated animals exhibited markedly decreased lung microvascular permeability (p < 0.05) and myeloperoxidase activity (p < 0.05). Blood-gas analysis demonstrated that the pretreated animals had significantly ameliorated pulmonary oxygenation function (p < 0.05). The serum concentration of tumor necrosis factor-alpha in rhEPO pretreated group was markedly decreased compared with that of I/R group (p < 0.05).. Pretreatment with rhEPO appears to attenuate I/R-induced lung injury. This function is partly related with the capacity that rhEPO inhibits the accumulation of polymorphonuclear neutrophils in lung tissue and decreases the systematic expression of tumor necrosis factor-alpha.

Topics: Animals; Capillary Permeability; Erythropoietin; Lung; Male; Oxygen; Partial Pressure; Peroxidase; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Reperfusion Injury; Respiratory Distress Syndrome; Tumor Necrosis Factor-alpha

The hypothesis that the protective effects of mild hypothermia against the pulmonary ischemia-reperfusion injury are mediated by endothelial nitric oxide synthase was tested.. Endothelial nitric oxide synthase knock-out and wild-type mice were sham operated or underwent a 1-hour occlusion of the left pulmonary hilum, followed by 5 hours of reperfusion. Temperature in the left pleural cavity during ischemia was maintained at either 36 degrees C (normothermia) or 32 degrees C (hypothermia). Inflammatory response (myeloperoxidase activity), endothelial barrier function (extravasation of Evans blue-labeled albumin), and endothelial nitric oxide synthase expression and phosphorylation were determined at the end of reperfusion.. After normothermic ischemia both strains had a similar mortality (wild-type, 22.9%; knock-out, 15.4%), which was completely abolished by hypothermia. Endothelial barrier function was disturbed after normothermic ischemia in both wild-type and knock-out mice. Mild hypothermia significantly reduced pulmonary Evans blue extravasation in wild-type mice, but not in knock-out mice. Myeloperoxidase activity increased after normothermic ischemia to the same degree in both strains. This response was significantly attenuated by hypothermia in wild-type mice, but not in knock-out mice. In wild-type mice, endothelial nitric oxide synthase expression and phosphorylation were higher after hypothermic ischemia than after normothermic ischemia. No effect of ischemia on expression of inducible nitric oxide synthase was found in wild-type or knock-out mice.. Hypothermic protection against pulmonary ischemia-reperfusion injury is dependent on endothelial nitric oxide synthase and is associated with increased expression and phosphorylation of endothelial nitric oxide synthase.

Topics: Animals; Capillary Permeability; Disease Models, Animal; Female; Hypothermia, Induced; Lung Diseases; Mice; Mice, Knockout; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Peroxidase; Phosphorylation; Reperfusion Injury

The damaging effects of intestinal ischemia-reperfusion (I/R) on the gut and remote organs can be attenuated by subjecting the intestine to a prior, less severe I/R insult, a process known as preconditioning. Because intestines of hibernating ground squirrels experience repeated cycles of hypoperfusion and reperfusion, we examined whether hibernation serves as a model for natural preconditioning against I/R-induced injury. We induced intestinal I/R in either the entire gut or in isolated intestinal loops using rats, summer ground squirrels, and hibernating squirrels during natural interbout arousals (IBA; body temperature 37-39 degrees C). In both models, I/R induced less mucosal damage in IBA squirrels than in summer squirrels or rats. Superior mesenteric artery I/R increased MPO activity in the gut mucosa and lung of rats and summer squirrels and the liver of rats but had no effect in IBA squirrels. I/R in isolated loops increased luminal albumin levels, suggesting increased gut permeability in rats and summer squirrels but not IBA squirrels. The results suggest that the hibernation phenotype is associated with natural protection against intestinal I/R injury.

Topics: Animals; Arousal; Female; Hibernation; Ileum; In Situ Nick-End Labeling; Intestinal Diseases; Male; Mesenteric Artery, Superior; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sciuridae

Renal ischaemia-reperfusion (I-R) can cause acute tubular necrosis and chronic renal deterioration. Endoglin, an accessory receptor for Transforming Growth Factor-beta1 (TGF-beta1), is expressed on activated endothelium during macrophage maturation and implicated in the control of fibrosis, angiogenesis and inflammation.. Endoglin expression was monitored over 14 days after renal I-R in rats. As endoglin-null mice are not viable, the role of endoglin in I-R was studied by comparing renal I-R injury in haploinsufficient mice (Eng(+/-)) and their wild-type littermates (Eng(+/+)). Renal function, morphology and molecular markers of acute renal injury and inflammation were compared.. Endoglin mRNA up-regulation in the post-ischaemic kidneys of rats occurred at 12 h after I-R; endoglin protein levels were elevated throughout the study period. Expression was initially localized to the vascular endothelium, then extended to fibrotic and inflamed areas of the interstitium. Two days after I-R, plasma creatinine elevation and acute tubular necrosis were less marked in Eng(+/-) than in Eng(+/+) mice. Significant up-regulation of endoglin protein was found only in the post-ischaemic kidneys of Eng(+/+) mice and coincided with an increased mRNA expression of the TGF-beta1 and collagen IV (alpha1) chain genes. Significant increases in vascular cell adhesion molecule-1 (VCAM-1) and inducible nitric oxide synthase (iNOS) expression, nitrosative stress, myeloperoxidase activity and CD68 staining for macrophages were evident in post-ischaemic kidneys of Eng(+/+), but not Eng(+/-) mice, suggesting that impaired endothelial activation and macrophage maturation may account for the reduced injury in post-ischaemic kidneys of Eng(+/-) mice.. Endoglin is up-regulated in the post-ischaemic kidney and endoglin-haploinsufficient mice are protected from renal I-R injury. Endoglin may play a primary role in promoting inflammatory responses following renal I-R.

Topics: Animals; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Collagen Type IV; Creatinine; Endoglin; Endothelium, Vascular; Enzyme Induction; Fibrosis; Gene Expression Regulation; Heterozygote; Inflammation; Intracellular Signaling Peptides and Proteins; Kidney; Kidney Tubular Necrosis, Acute; Macrophages; Male; Mice; Mice, Inbred C57BL; Mice, Mutant Strains; Monocytes; Nitric Oxide Synthase Type II; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; RNA, Messenger; Transforming Growth Factor beta1; Vascular Cell Adhesion Molecule-1

In reperfusion injury activation of coagulation and inflammation contribute to organ dysfunction. Activated protein C (APC) exhibits anticoagulant and anti-inflammatory properties in models of reperfusion injury. We hypothesized that APC could be cardioprotective after ischemia and cardiopulmonary bypass (CPB).. 20 pigs, undergoing 120 min of CPB and aortic cross-clamping, were randomized to receive 1 mg of human APC or placebo to the last cardioplegic solution given 15 min before declamping to the systemic circulation. After aortic declamping the heart was supported by continuing CPB for 30 min followed by 30 min surveillance. Thrombin-antithrombin complexes, neutrophil L-selectin expression in blood and myeloperoxidase activity (MPO) of myocardial biopsies were measured.. There was no indication of APC-induced increased bleeding. Thrombin levels were significantly lower in the APC group than in the placebo group and so were the rates of thrombin formation during the first 3 min of reperfusion and between 10 and 30 min after declamping. There were no differences in MPO or in the proportion of L-selectin (+) to L-selectin (-) neutrophils between groups. Significant systolic hypotension in the APC group was observed at 30 and 45 min compared with the placebo group which associated with the increased mortality observed in the APC group (p = 0.019).. Human APC in cardioplegic solution during CPB in pigs, decreased reperfusion induced thrombin formation with no associated bleeding. No anti-inflammatory effects of human APC were seen. However, in this setting, APC caused hemodynamic deterioration. The observed phenomenon could be explained by systolic hypotension potentially produced by the release of vasoactive substances generated by the APC activation of PARs in the endothelium.

Topics: Animals; Antithrombin III; Cardioplegic Solutions; Cardiopulmonary Bypass; Coronary Vessels; Disease Models, Animal; Heart Ventricles; Hemodynamics; Humans; Hypotension; L-Selectin; Myocardium; Neutrophils; Peptide Hydrolases; Peroxidase; Protein C; Random Allocation; Receptors, Proteinase-Activated; Reperfusion Injury; Swine; Time Factors

There is a great evidence that reactive oxygen species (ROS) play an important role in the pathophysiology of ischemia-reperfusion (I/R) injury in skeletal muscle. Caffeic acid phenethyl ester (CAPE) is a component of honeybee propolis. It has antioxidant, anti-inflammatory and free radical scavenger properties. The aim of this study is to determine the protective effects of CAPE against I/R injury in respect of protein oxidation, neutrophil in filtration, and the activities of xanthine oxidase (XO) and adenosine deaminase (AD) on an in vivo model of skeletal muscle I/R injury. Rats were divided into three equal groups each consisting of six rats: Sham operation, I/R, and I/R plus CAPE (I/R+CAPE) groups. CAPE was administered intraperitoneally 60 min before the beginning of the reperfusion. At the end of experimental procedure, blood and gastrocnemius muscle tissues were used for biochemical analyses. Tissue protein carbonyl (PC) levels and the activities of XO, myeloperoxidase (MPO) and AD in I/R group were significantly higher than that of control (p < 0.01, p < 0.05, p < 0.01, p < 0.005, respectively). Administration of CAPE significantly decreased tissue PC levels, MPO and XO activities in skeletal muscle compared to I/R group (p < 0.01, p < 0.05, p < 0.05, respectively). In addition, plasma creatine phosphokinase (CPK), XO and AD activities were decreased in I/R+CAPE group compared to I/R group (p < 0.05, p < 0.05, p < 0.001). The results of this study revealed that free radical attacks may play an important role in the pathogenesis of skeletal muscle I/R injury. Also, the potent free radical scavenger compound, CAPE, may have protective potential in this process. Therefore, it can be speculated that CAPE or other antioxidant agents may be useful in the treatment of I/R injury as well as diffused traumatic injury of skeletal muscle.

Topics: Adenosine Deaminase; Animals; Caffeic Acids; Creatine Kinase; Male; Muscle, Skeletal; Peroxidase; Phenylethyl Alcohol; Protein Carbonylation; Rats; Rats, Wistar; Reperfusion Injury; Xanthine Oxidase

1. Splanchnic artery occlusion (SAO) followed by reperfusion causes endothelial injury and inflammation which contribute to the pathophysiology of shock. We investigated the effects of relaxin (RLX), known to afford protection against the deleterious effects of cardiac ischemia/reperfusion, given to rats subjected to splanchnic artery occlusion and reperfusion (SAO/R)-induced splanchnic injury. 2. RLX (30 ng kg(-1), 15 min. before reperfusion) significantly reduced the drop of blood pressure and high mortality rate caused by SAO/R. RLX also reduced histopathological changes, leukocyte infiltration (myeloperoxidase) and expression of endothelial cell adhesion molecules in the ileum. RLX counteracted free radical-mediated tissue injury, as judged by significant decrease in the tissue levels of peroxidation and nitration products (malondialdehyde, nitrotyrosine), DNA damage markers (8-hydroxy-2'-deoxyguanosine, poly-ADP-ribosylated DNA) and consumption of tissue antioxidant enzymes (superoxide dismutase). As a result, RLX led to a reduction of ileal cell apoptosis (caspase 3, terminal deoxynucleotidyltransferase-mediated UTP end labeling). The effects of RLX appear specific, as inactivated RLX substituted for the bioactive hormone had no effects. 3. In conclusion, these results show that RLX exerts a clear-cut protective effect in SAO/R-induced splanchnic injury, likely due to endothelial protection, decreased leukocyte recruitment and hindrance of free radical-mediated tissue injury leading to cell death, lethal complications and high mortality rate. Thus, RLX could be used therapeutically in intestinal ischemia.

Topics: Animals; Arterial Occlusive Diseases; Immunohistochemistry; In Situ Nick-End Labeling; Intestinal Mucosa; Intestines; Malondialdehyde; Peroxidase; Poly(ADP-ribose) Polymerases; Rats; Rats, Wistar; Relaxin; Reperfusion Injury; Splanchnic Circulation; Superoxide Dismutase

It seems inevitable that non-beating-heart donors will be utilized to resolve the shortage of donors for clinical lung transplantation. The control of warm ischemia-reperfusion injury is crucial in manipulating non-beating-heart donors. We hypothesized that nebulization of a beta2-adrenoreceptor agonist, salmeterol xinafoate (SLM), during warm ischemia would increase lung tissue cyclic adenosine monophosphate (cAMP) levels, resulting in lung protection.. Two studies were conducted. The first investigated the effect of SLM nebulization during ischemia on pulmonary ischemia-reperfusion injury, using an isolated rat lung-perfusion model. The heart-lung block was excised with cannulation of the pulmonary artery and vein, exposed to 55 minutes of ischemia at 37 degrees C, and subsequently reperfused for 60 minutes. Several parameters were measured during reperfusion. In the second study, to measure changes in lung tissue cAMP levels during warm ischemia with or without SLM nebulization, rat lungs were harvested and exposed to 60 minutes of warm ischemia with ventilation.. Salmeterol xinafoate nebulization significantly decreased the pulmonary shunt fraction, airway resistance, and pulmonary vascular resistance. It also inhibited pulmonary edema throughout the reperfusion period. Lung tissue cAMP was effectively maintained by SLM nebulization at the end of reperfusion. Myeloperoxidase activity in the lungs was decreased significantly by SLM nebulization. Lung tissue cAMP levels decreased during the 60 minutes of warm ischemia, but increased with SLM nebulization (p < 0.01).. Our results confirmed that SLM nebulization during warm ischemia maintained lung tissue cAMP levels, resulting in the alleviation of pulmonary warm ischemia-reperfusion injury.

Topics: Adenosine Triphosphate; Adrenergic beta-Agonists; Aerosols; Albuterol; Animals; Cyclic AMP; Energy Metabolism; Lung; Male; Peroxidase; Rats; Rats, Inbred Lew; Reperfusion Injury; Salmeterol Xinafoate; Vascular Resistance; Warm Ischemia

Lung ischemia reperfusion injury continues to adversely affect patient and graft survival after transplantation. While the role of interleukin-6 has been studied in ischemia-reperfusion models of intestine, liver, and heart, its participation in lung reperfusion injury has not been characterized.. We administered recombinant interleukin-6 to rat lungs through the intratracheal route before inducing left lung ischemia and reperfusion. Multiple in-vivo indicators of left lung injury were studied, as were transactivation patterns for nuclear factor kappa B and signal transduction and activators of transcription-3. Downstream effects on the elaboration of proinflammatory chemokines and cytokines were also studied.. Recombinant interleukin-6 reduced endothelial disruption and neutrophil sequestration in left lung and alveolar spaces, resulting in improved oxygenation after ischemia and 4 hours of reperfusion. This protection was associated with decreased nuclear factor kappa B and signal transduction and activators of transcription-3 nuclear translocation early in reperfusion, and diminished proinflammatory mediator secretion late in reperfusion.. Further studies focusing on the effects of recombinant interleukin-6 in large animal models are warranted, as this may be a novel strategy to improve outcomes after lung transplantation. Intratracheal administration may focus its efficacy on the lung while reducing effects on other organ systems during organ procurement.

Topics: Active Transport, Cell Nucleus; Animals; Bronchoalveolar Lavage Fluid; Capillary Permeability; Inflammation Mediators; Interleukin-6; Lung; Oxygen; Peroxidase; Rats; Rats, Long-Evans; Recombinant Proteins; Reperfusion Injury; STAT3 Transcription Factor

PARP stabilizes DNA and modulates inflammation in murine models of sepsis, stroke, and myocardial infarction. Previous studies have shown that systemic PARP inhibition before hindlimb ischemia preserves tissue viability and modulates cytokine synthesis during reperfusion. The purpose of this study was to determine whether intra-muscular (IM) administration of PJ34, a potent inhibitor of PARP, after the onset of acute hindlimb ischemia (post hoc) modulates the local production of inflammatory mediators during ischemia/reperfusion (I/R).. The control tension tourniquet was used to establish unilateral hindlimb ischemia in mice for 3 h followed by 48 h I/R. The treatment group (PJ) received IM PJ34 (10 mg/kg) in the affected hindlimb 90 min into ischemia whereas the control group (UN) received IM saline (150 uL) at the same time point. Skeletal muscle viability (MTT mitochondrial activity), local neutrophil chemoattractant protein (KC), Interleukin 6 (IL-6), Interleukin 1beta (IL-1beta), and Myeloperoxidase (MPO) levels were measured in protein extracts after the reperfusion period.. Muscle viability (102% +/- 10 PJ, 78% +/- 4 UN, P = 0.04), IL-B (21.1 +/- 1.3 PJ, 15.5 +/- 1.0 UN, P = 0.02), and IL-6 levels (16.3 +/- 1.2 PJ, 10.9 +/- 1.4 UN, P = 0.04) after 48 I/R were significantly higher in PJ. KC and MPO levels were higher in PJ but neither reached statistical significance.. Post hoc PJ34 therapy appears to protect skeletal muscle from I/R injury despite increased levels of local cytokines. These initial findings support the role of local post hoc therapy in the treatment of acute limb threatening ischemia suggesting that further study of this novel therapy is warranted.

Topics: Animals; Enzyme-Linked Immunosorbent Assay; Hindlimb; Interleukin-1beta; Interleukin-6; Laser-Doppler Flowmetry; Mice; Muscle, Skeletal; Peroxidase; Phenanthrenes; Poly(ADP-ribose) Polymerase Inhibitors; Reperfusion Injury

The aim of this study is to investigate the role of proteasome in the pathogenesis of lung injury induced by intestinal ischemia/reperfusion (I/R) by examining the effect of the proteasome inhibitor lactacystin on neutrophil infiltration, intracellular adhesion molecule-1 (ICAM-1) expression and nuclear factor kappa B (NF-kappaB) activation. Thirty-two Wistar rats were divided into (1) control, (2) intestinal I/R, (3) 0.2 mg/kg lactacystin pretreated, and (4) 0.6 mg/kg lactacystin pretreated groups (n=8). Injuries in lung and intestine were induced by intestinal I/R, and were characterized by histological edema, hemorrhage and infiltration of inflammatory cells. The results showed a significant increase in serum creatine kinase B (CK-B) and lung water content in intestine and lung injuries. As compared with the control group, the myeloperoxidase (MPO) activity in intestine and lung as well as the serum TNF-alpha level increased significantly in intestinal I/R group. Simultaneously, expression of ICAM-1 and NF-kappaB p65 was also observed in the I/R group. Pre-treatment with lactacystin markedly reduced 20S proteasome activity in circulating white blood cells and ameliorated intestine and lung injuries. These results demonstrated that the proteasome participates in the pathogenesis of lung injury induced by intestinal I/R. Lactacystin as a proteasome inhibitor can prevent this kind of injury by decreasing ICAM-1 and TNF-alpha production via the inhibition of NF-kappaB activation.

Topics: Animals; Body Water; Creatine Kinase, BB Form; Intestines; Lung; Lung Injury; Male; Peroxidase; Proteasome Endopeptidase Complex; Proteasome Inhibitors; Rats; Rats, Wistar; Reperfusion Injury; Tumor Necrosis Factor-alpha

Testicular torsion causes an enhanced formation of reactive oxygen species which contributes to the pathophysiology of ischemia-reperfusion injury in the testis. We evaluated here the effect of caffeic acid phenethyl ester (CAPE), a new antioxidant and anti-inflammatory agent on histopathological changes in testicular ischemia-reperfusion injury. Adult male Wistar rats were divided into six groups of five each: control group 1 (n=5), sham operation group 2 (n=5), torsion/detorsion (T/D) group 3 (n=5), T/D+saline group 4 (n=5), T/D+CAPE group 5 (n=5) and T/D+CAPE group 6 (n=5). Group 1 served to determine baseline values of histopathological parameters, group 2 animals that underwent sham operation served as a control, while groups 3-6 animals were subjected to left unilateral torsion (2 h) and detorsion (24 h) periods. All the groups were sacrified 24 h later except group 6. CAPE was injected 2 days with the same dose to the group 6 and it was sacrified 48 h later. One testis removed and fixed in Bouin's solution. After routine tissue processing myeloperoxidase (MPO) and inducible nitric oxide synthase (iNOS) immunohistochemical methods were studied from paraffin embedded tissues. Treating rats with CAPE (applied at 10 micromol/kg, 30 min prior to T/D) attenuated the testicular injury and as well as the tissue levels of MPO. At the same time testis tissue showed a decrease in iNOS activity. Our results suggest that CAPE treatment have a protective role on testicular T/D and this effect may be due to inhibiting the neutrophil mediated cellular injury.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; Caffeic Acids; Immunohistochemistry; Injections, Intraperitoneal; Male; Nitric Oxide Synthase Type II; Peroxidase; Phenylethyl Alcohol; Rats; Rats, Wistar; Regional Blood Flow; Reperfusion Injury; Spermatic Cord Torsion; Testis

Glycyrrhizin, an agent that can bind to selectins and inhibit their ability to bind neutrophils, was found to be effective in preventing tissue edema caused by ischemia-reperfusion in a rabbit model.. Complete ischemia was produced by applying a tight Esmarch tourniquet to the hind limbs of 24 Japanese white rabbits. Immediately before and 1 h after release of the tourniquet, 12 animals were given glycyrrhizin intravenously; 12 controls received saline.. The mean relative increase in the circumference of the shins before and after ischemia-reperfusion with or without glycyrrhizin treatment was 4.6% +/- 2.4% and 9.6% +/- 4.2%, respectively, indicating that tissue edema caused by the ischemia-reperfusion was significantly attenuated by glycyrrhizin. Histological studies of cross sections of the anterior tibial muscle 24 h after reperfusion showed a significant reduction in the incidence of necrotic muscle fibers in the glycyrrhizin-treated animals compared with the controls that did not receive glycyrrhizin. The mRNA levels of P- and E-selectin 24 h after reperfusion were significantly higher in the ischemic anterior tibial muscle than in the nonischemic normal muscle. After 24 h of reperfusion, the mean activity of myeloperoxidase, a neutrophil-specific enzyme, in the anterior tibial muscles of the group given glycyrrhizin (0.0022 +/- 0.0013 absorbance units) was lower than that of the untreated group (0.027 +/- 0.026 absorbance units).. These data suggest that glycyrrhizin treatment is effective in suppressing the acute inflammatory reaction or edema following ischemia-reperfusion and might be potentially useful in clinical practice for preventing ischemia-reperfusion injuries to the extremities.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Capillaries; Edema; Endothelium, Vascular; Glycyrrhizic Acid; Hindlimb; Peroxidase; Rabbits; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Selectins

The present study aimed to investigate the possible beneficial activities of resveratrol (3,5,4'-trans-trihydroxystilbene), a natural phytoalexin, on contractility and oxidant damage after ischemia/reperfusion (I/R) of the rat urinary bladder.. The abdominal aorta of Sprague-Dawley rats was occluded for 60 min to induce ischemia and then allowed 60 min of reperfusion. Resveratrol (10 mg/kg) or saline was administered intraperitoneally 15 min before ischemia and immediately before reperfusion. In the sham-operated group, the abdominal aorta was left intact and the animals were treated with resveratrol or saline. The bladder samples were either used for functional studies or stored for biochemical assays.. In the I/R group, the isometric contractile responses of the bladder strips to carbachol (CCh; 10(-8)-10(-4) mol/l) were lower than those of the control group and were reversed by treatment with resveratrol. Histological evaluation revealed loss of urothelial cells, detachment and loss of urothelial cells and local ulcerated areas and severe inflammatory cell infiltration in the untreated I/R group, and regeneration of luminal mucosa and a significant decrease in the density of the inflammatory cell population in the resveratrol-treated I/R group. Lipid peroxidation and the myeloperoxidase activity of the bladder tissues in the I/R group were higher than in the sham-operated group. Resveratrol treatment in the I/R group decreased these parameters compared with I/R alone. Similarly, the significant decrease in tissue glutathione level in the I/R group compared with controls was also prevented by resveratrol.. Treatment with resveratrol almost completely reversed the low contractile responses of the rat urinary bladder to CCh and prevented oxidative tissue damage following I/R.

Topics: Animals; Female; Glutathione; In Vitro Techniques; Lipid Peroxidation; Male; Muscle Contraction; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Resveratrol; Stilbenes; Urinary Bladder

Complement activation augments myocardial cell injury and apoptosis during ischemia/reperfusion (I/R), whereas complement system inhibition with C1 inhibitor (C1INH), a serine protease inhibitor, exerts markedly cardioprotective effects. Our recent data demonstrate that C1INH prevents vascular endothelial cell apoptosis and a "modified" form of the reactive center loop-cleaved, inactive C1INH (iC1INH) plays an anti-inflammatory role in endotoxin shock. The aim of this study was to determine whether C1INH protects against myocardial cell injury via an anti-apoptotic activity or anti-inflammatory effect. In a rat model of acute myocardial infarction (AMI) induced by I/R, administration of C1INH protected against cardiomyocytic apoptosis via normalization of ratio of the Bcl-2/Bax expression in the myocardial infarct area. C1INH improved parameters of cardiac function and hemodynamics and reduced myocardial infarct size (MIS). In addition, myocardial and blood myeloperoxidase (MPO) activity, a marker of neutrophil infiltration, was decreased by treatment of C1INH. In cultured H9c2 rat cardiomyocytic cells, C1INH blocked hypoxia/reoxygenation-induced apoptosis in the absence of sera associated with inhibition of cytochrome c translocation and suppression of caspase-3 activation. The proportion of Bcl-2/Bax expression induced by hypoxia/reoxygenation was reversed by C1INH. Importantly, iC1INH also revealed these similar effects, indicating that C1INH has a direct anti-apoptotic activity. Therefore, these studies support the hypothesis that C1INH, in addition to inhibition of activation of the complement and contact systems, improves outcome in I/R-mediated myocardial cell injury via an anti-apoptotic activity independent of serine protease inhibitory activity.

Topics: Animals; Anti-Inflammatory Agents; Apoptosis; Biological Transport; Cardiotonic Agents; Caspase 3; Caspases; Complement C1; Complement C1 Inhibitor Protein; Enzyme Activation; Myocardium; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Intravascular accumulation of blood cells after brain ischemia-reperfusion can cause obstruction of cerebral blood flow and tissue hypoxia/ischemia as a consequence. In the present study, we examined temporal and topographic changes of tissue hypoxia/ischemia after occlusion of the middle cerebral artery (MCA) for 60 min in rats with immunohistochemical staining for hypoxia (2-nitroimidazole hypoxia marker: hypoxyprobe-1 adducts). Our results showed that tissue hypoxia expressed as positive staining for hypoxyprobe-1 adducts preceded neuronal degeneration. Platelets and granulocytes were detected close to the hypoxyprobe-1 adducts positive area. These results suggested that the hypoxic environment could persist even after reperfusion of MCA, because of vascular obstruction with accumulation of platelets and granulocytes.

Topics: Animals; Brain; Brain Ischemia; Gene Expression Regulation, Enzymologic; Integrin beta3; Male; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Time Factors

The present study was designed to examine whether resveratrol, a potent antioxidant, protects against renal ischemia-reperfusion (I/R) injury.. Wistar albino rats were unilaterally nephrectomized and subjected to 45 min of renal pedicle occlusion followed by 6 h of reperfusion. Resveratrol (RVT, 30 mg/kg, i.p.) or vehicle was administered twice, at 30 min prior to ischemia and immediately before the reperfusion period. At the end of the reperfusion period, rats were decapitated and kidney samples were taken for histological examination or determination of levels of renal malondialdehyde (MDA), an end product of lipid peroxidation; glutathione (GSH), a key antioxidant; and myeloperoxidase (MPO) activity, an index of tissue neutrophil infiltration. Formation of reactive oxygen species in hepatic tissue samples was monitored by using chemiluminescence (CL) technique with luminol and lucigenin probes. Renal tissue collagen content as a fibrosis marker was also determined, while serum creatinine and urea concentrations were measured for the evaluation of renal function. Tumor necrosis factor-alpha (TNF-alpha ) and lactate dehydrogenase (LDH) were also assayed in serum samples.. Ischemia/reperfusion caused a significant decrease in tissue GSH level, which was accompanied by significant increases in the renal luminol and lucigenin CL values, MDA level, MPO activity and collagen content. Similarly, serum creatinine and BUN levels, as well as LDH and TNF-alpha, were elevated in the I/R group as compared to control group. On the other hand, resveratrol treatment reversed all these biochemical indices, as well as histopathological alterations that were induced by I/R.. Findings of the present study suggest that resveratrol exerts renoprotective effects via its radical scavenging and antioxidant activities, which appear to involve the inhibition of tissue neutrophil infiltration.

Topics: Acridines; Animals; Antioxidants; Blood Urea Nitrogen; Creatine; Glutathione; Kidney Diseases; L-Lactate Dehydrogenase; Luminol; Male; Malondialdehyde; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Resveratrol; Stilbenes

To investigate the neuro-protective effect of Xuesaitong Injection (XST) on brain inflammatory response after transient focal cerebral ischemia/reperfusion in rats.. Focal cerebral ischemia/reperfusion models of male rats were induced by transient occlusion for 2 h of middle cerebral artery (MCA) which was followed by 24 h reperfusion. XST was administered through intraperitoneal injection of 25 mg/kg or 50 mg/kg at 4 h after the onset of ischemia. After reperfusion for 24 h, the neurological function score was evaluated, the brain edema was detected with dry-wet weight method, the myeloperoxidase (MPO) activity and the expression of intercellular adhesion molecule-1 (ICAM-1) of ischemic cerebral cortex and caudate putamen was determined by spectrophotometry and immunohistochemistry respectively.. XST not only lowered neurological function score at the dose of 50 mg/kg, but reduced brain edema and inhibited MPO activity and ICAM-1 expression as compared with the ischemia/reperfusion model group (P < 0.01).. XST has a definite effect on inhibiting the expression of ICAM-1 and neutrophil infiltration in rats with cerebral ischemia/reperfusion when treatment started at 4 h after ischemia onset, and also attenuates inflammation in the infarcted cerebral area.

Topics: Animals; Brain Edema; Brain Ischemia; Drugs, Chinese Herbal; Encephalitis; Intercellular Adhesion Molecule-1; Male; Neuroprotective Agents; Neutrophils; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Saponins

There is increasing evidence to suggest that reactive oxygen and nitrogen species play a role in the pathogenesis of renal ischemia-reperfusion (I/R) injury. This study was designed to determine the possible protective effects of trapidil treatment against oxidative and nitrosative tissue injury of kidney induced by I/R. A renal I/R injury was induced by a left renal pedicle occlusion by ischemia for 45 minutes, followed by 1 hour of reperfusion with contralateral nephrectomy in I/R and I/R + trapidil groups. Trapidil (8 mg/kg intravenously) was administrated immediately before reperfusion phase. At the end of the reperfusion period, rats were killed. Then, renal tissue samples were taken for biochemical analysis and histopathological evaluation, and blood samples were obtained to determinate serum urea, aspartate aminotransferase (AST), and tumor necrosis factor-alpha (TNF-alpha) levels. Ischemia-reperfusion injury caused significant increases in myeloperoxidase activity and malondialdehyde and 3-nitrotyrosine levels in renal tissue and elevated serum urea, AST, and TNF-alpha levels. In addition, severe deterioration of renal morphology was seen in the I/R group. Trapidil treatment significantly reduced in biochemical parameters, as well as serum urea, AST, and TNF-alpha levels. Furthermore, renal tissue injury was markedly attenuated with trapidil treatment. These data suggest that reactive oxygen species and reactive nitrogen species play a causal role in I/R-induced renal tissue, and trapidil has a renoprotective effect against oxidative and nitrosative kidney damage.

Topics: Animals; Kidney; Malondialdehyde; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Trapidil; Tumor Necrosis Factor-alpha; Tyrosine; Vasodilator Agents

The aim of this study was to investigate whether the protective effect of endothelin-A (ET(A)) receptor antagonist BQ-123 against renal ischemia reperfusion (I/R) injury is related to nitric oxide (NO) production. Sprague-Dawley rats were divided into six groups: control, I/R, N sup omega nitro-L-arginine methyl ester (L-NAME), BQ, BQ+L-NAME, BQ+L-NAME+L-Arg groups. After urethane anesthesia, 30min renal ischemia and 2h reperfusion were performed in all groups except control group. Mean arterial pressures (MAP) during reperfusion in all L-NAME-treated groups were higher than during pre-ischemia and ischemia, however, MAP at 60th and 120th minute of reperfusion in control and BQ groups were lower than during ischemia. MAP of L-NAME-treated groups were significantly higher than the other groups during reperfusion period. The I/R caused lipid peroxidation and protein oxidation, however, BQ-123 treatment prevented oxidant injury. The inhibition of NO production prevented effect of BQ-123 treatment. Also, BQ-123 treatment caused an increase in superoxide dismutase and catalase activities. Both BQ-123 and L-NAME treatments prevented high xanthine oxidase activity. BQ-123 prevented risen myeloperoxidase activity and L-NAME reversed this effect of BQ-123 just like the addition of L-arginine to the treatment altered the effect of L-NAME. The plasma BUN was affected as increasing manner from L-NAME treatments; on the other hand, plasma Cr and Na concentrations were affected as decreasing manner from BQ-123 treatments. ET(A) receptor antagonist BQ-123 may be revealed a protective agent against renal I/R injury with a possible secondary pathway via its antioxidant effects. We suggest that BQ-123 may mediate the protective effect via a NO-dependent mechanism.

Topics: Animals; Blood Pressure; Blood Urea Nitrogen; Catalase; Endothelin A Receptor Antagonists; Endothelin-1; Enzyme Inhibitors; Glutathione Peroxidase; Kidney; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase; Organ Size; Peptides, Cyclic; Peroxidase; Rats; Rats, Sprague-Dawley; Renal Circulation; Reperfusion Injury; Sodium; Superoxide Dismutase; Thiobarbituric Acid Reactive Substances; Xanthine Oxidase

There is increasing evidence to suggest that toxic oxygen radicals play an essential role in the pathogenesis of ischemia/reperfusion (I/R) injury in the kidney. This study was designed to investigate the effects of leflunomide, an isoxazole derivative and a unique immunomodulatory agent, in I/R-induced renal injury in rats.. Forty female Sprague-Dawley rats were divided equally into four groups: (I) control (only leflunomide 10 mg/kg, intragastrically treated); (II) sham operated (only unilateral nephrectomy); (III) I/R; and (IV) leflunomide (10 mg/kg for two doses prior to experiment) plus I/R groups. In groups III and IV, after unilateral nephrectomy, the rats were subjected to 60 min of left renal pedicle occlusion, followed by 6 h of reperfusion. At the end of the reperfusion period, rats were killed and kidneys and blood were removed. Catalase, myeloperoxidase and xanthine oxidase activities, and malondialdehyde, nitric oxide and protein carbonyl levels were determined in renal tissue. Serum creatinine, blood urea nitrogen and aspartate aminotransferase were measured for the evaluation of renal function. In histopathological examination, renal damage was scored 0-3.. Group III animals demonstrated severe deterioration of renal function, renal morphology and a significant renal oxidative stress. Pretreatment of animals with leflunomide markedly attenuated renal dysfunction, morphological alterations, reduced elevated oxidative stress products levels and restored the depleted renal antioxidant enzyme.. The findings imply that oxygen radicals play a causal role in I/R-induced renal injury, and leflunomide exerts renoprotective effects probably by the radical scavenging and antioxidant activities with immunomodulatory effect.

Topics: Animals; Antioxidants; Aspartate Aminotransferases; Blood Urea Nitrogen; Catalase; Creatinine; Female; Immunosuppressive Agents; Isoxazoles; Kidney; Leflunomide; Lipid Peroxidation; Nitric Oxide; Oxidative Stress; Peroxidase; Protein Carbonylation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Xanthine Oxidase

Ischemia-reperfusion (I/R) injury of the liver occurs in many clinical cases. Many steps are associated with hepatic I/R injury, including the release of many inflammatory molecules and infiltration of neutrophils into the liver. Recent studies revealed that hypertonic saline (HTS) has a strong anti-inflammatory effect and can inhibit a varity of neutrophil functions. So pretreatment with HTS may attenuate the liver injury associated with I/R. In this study, rats were divided into three groups: the sham group (S group), hepatic I/R group (I/R group), and HTS pretreatment group (HTS group). Serum ALT and myeloperoxidase (MPO) activity were determined. Serum tumor necrosis factor alpha (TNF-alpha) and interleukin 10 (IL-10) were determined by enzyme-linked immunosorbent assay (ELISA). Reverse transcription polymerase chain reaction analysis was used to assess the mRNA expressions of TNF-alpha and IL-10. Protein expressions of TNF-alpha, IL-10, STAT3, and phosphorylated STAT3 were analyzed by Western blot. Results showed that HTS pretreatment can augment the release of endogenous IL-10 by activating STAT3 in the process of hepatic I/R injury. Serum ALT levels, MPO activity in liver, generation of TNF-alpha, and infiltration of neutrophils in liver were inhibited in the HTS group. So we concluded that HTS pretreatment attenuates hepatic I/R injury by increasing the release of endogenous IL-10.

Topics: Alanine Transaminase; Animals; Interleukin-10; Liver; Liver Diseases; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Saline Solution, Hypertonic; STAT3 Transcription Factor; Tumor Necrosis Factor-alpha

Microcirculatory dysfunctions and mast cell reactions play important roles in hypoxic tissue injuries. The aims of this study were to characterize the effects of hindlimb ischemia-reperfusion on the periosteal microcirculation and to define the consequences of systemic phosphatidylcholine therapy during this condition.. Microcirculatory changes were visualized by means of fluorescence intravital videomicroscopy in anesthetized Wistar rats. 60 min of complete hindlimb ischemia was followed by a 180-min reperfusion in the presence of phosphatidylcholine treatment (50 mg/kg iv; in the second 10 min of reperfusion) or vehicle. Further two groups served as vehicle- or PC-treated sham-operated controls. The proportion of degranulated mast cells and the leukocyte accumulation (myeloperoxidase, MPO assay) were determined in muscle biopsies.. Ischemia-reperfusion significantly increased the muscle MPO activity (from 14.94 to 63.45 mU/mg) and the proportion of degranulated mast cells (to 82.5%). The periosteal capillary red blood cell velocity (RBCV) and the functional capillary density (FCD) had decreased, while the primary and secondary leukocyte-endothelial cell interactions had increased by the end of reperfusion (rolling from 20.8 to 40.0%, and firm adherence from 254 to 872 mm-2). Phosphatidylcholine treatment decreased the leukocyte rolling and sticking, preserved the FCD and improved the RBCV The mast cell degranulation and MPO activity diminished significantly in the muscle layer.. Mast cell degranulation accompanies ischemia-reperfusion-induced periosteal microcirculatory derangement. Systemic phosphatidylcholine treatment affords protection through ameliorating secondary inflammatory reactions.

Topics: Animals; Blood Flow Velocity; Capillaries; Erythrocytes; Hindlimb; Leukocytes; Male; Mast Cells; Muscle, Skeletal; Peroxidase; Phosphatidylcholines; Rats; Rats, Wistar; Reperfusion Injury; Time Factors; Video Recording

This study aimed to explore the hypothesis that activated complement components contribute significantly to I/R (ischaemia/reperfusion) injury in skeletal muscle. After 50, 70 and 90 min of tourniquet ischaemia and 24 h of reperfusion, viability of the medial gastrocnemius muscle in CBA-C57BL/6 wild-type mice, assessed histochemically by reduction of NBT (Nitro Blue Tetrazolium) dye, was 60, 21 and 8% respectively. Skeletal muscle viability after 70 min of ischaemia and 24 h of reperfusion in transgenic mice expressing a combination of human CD46, CD55 and CD59, all inhibitors of complement activation, was 45% compared with 24% in ischaemic reperfused wild-type mice (P=0.008; n=6 per group). Muscle from sham-treated transgenic mice and wild-type littermates had no significant loss of viability relative to normal contralateral gastrocnemius muscle. A significant reduction in myeloperoxidase activity (a measure of neutrophil infiltration), xanthine oxidase activity (a source of free radicals) and water content (a measure of oedema) was observed in ischaemic reperfused muscle from transgenic mice compared with ischaemic reperfused wild-type muscle (P<0.05). Haematoxylin and eosin-stained histological sections also showed less damage and less apparent leucocyte infiltration in muscles from ischaemic reperfused transgenic mice than those from wild-type animals given the same degree of injury. Muscles from sham-treated transgenic and wild-type controls were almost identical with normal muscle. It is concluded that complement activation contributes to the pathogenesis of I/R injury in murine skeletal muscle, resulting in increased neutrophil infiltration into the injured muscle, increased free radical production and vascular permeability during reperfusion, and a net detrimental effect on muscle viability.

Topics: Animals; Antigens, CD; CD55 Antigens; CD59 Antigens; Complement Inactivator Proteins; Edema; Hindlimb; Humans; Membrane Cofactor Protein; Membrane Glycoproteins; Mice; Mice, Inbred C57BL; Mice, Inbred CBA; Mice, Transgenic; Models, Animal; Muscle, Skeletal; Neutrophil Infiltration; Peroxidase; Reperfusion Injury; Xanthine Oxidase

There is evidence that physical activity is associated with decreased brain injury resulting from transient middle cerebral artery (MCA) occlusion. We investigated whether exercise could reduce stroke-induced brain inflammatory injury and its associated mediators. Sprague Dawley rats (3 months old) were subjected to 30 min exercise on a treadmill each day for 1-3 weeks. Stroke, in exercised and non-exercised animals, was then induced by a 2-h MCA occlusion followed by 48 h of reperfusion using an intraluminal filament. Endothelial expression of the intercellular adhesion molecule 1 (ICAM-1) and leukocyte infiltration were determined by immunocytochemistry. Expressions of tumor necrosis factor-alpha (TNF-alpha) and ICAM-1 mRNA were detected using a real-time reverse transcriptase-polymerase chain reaction in ischemic rats with or without exercise, and in non-ischemic control rats following exercise. Expression of TNF-alpha increased after exercise for 2 and 3 weeks. The overexpression of TNF-alpha was not further elevated in 3-week exercised rats subjected to a transient MCA occlusion and 6 or 12 h of reperfusion, as compared to that in non-exercised rats. Furthermore, ICAM-1 mRNA expression remained at significantly (P<0.01) low levels in exercised animals during ischemia/reperfusion. Pre-ischemic exercise significantly (P<0.01) reduced numbers of ICAM-1-positive vessels and infiltrating leukocytes in the frontoparietal cortex and dorsolateral striatum in ischemic rats after 48 h of reperfusion. Exercised ischemic rats demonstrated an 11+/-7% infarct volume of contralateral hemisphere as compared to a 52+/-3% volume in non-exercised ischemic rats. The data suggests that exercise inhibits inflammatory injury (i.e., decreased expression of inflammatory mediators and reduced accumulation of leukocytes) during reperfusion, leading to reduced brain damage. Chronically increased expression of TNF-alpha during exercise prevent the same downstream inflammatory events as does acutely elevated TNF-alpha after ischemia/reperfusion.

Topics: Analysis of Variance; Animals; Cerebral Cortex; Cerebral Infarction; Corpus Striatum; Exercise Test; Gene Expression; Immunohistochemistry; Infarction, Middle Cerebral Artery; Inflammation; Intercellular Adhesion Molecule-1; Leukocytes; Male; Peroxidase; Physical Conditioning, Animal; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Time Factors; Tumor Necrosis Factor-alpha

The optimal strategy for pulmonary graft preservation remains elusive. Experimental work and initial clinical experience support low-potassium dextran solutions as lung perfusates. We have previously shown a protective effect of prostaglandin E 1 on ischemia-reperfusion injury in lung transplantation by a shift from proinflammatory to anti-inflammatory cytokines in a rat lung transplantation model. In this study, we tested the hypothesis that the addition of a prostacyclin analog (iloprost) to low-potassium dextran might lead to improved surfactant and ultimately graft function.. In a randomized, blinded study with a porcine left single-lung transplantation model, donor lungs were flushed with 1 L of either low-potassium dextran solution or low-potassium dextran solution modified by the addition of 250 microg iloprost (n = 6 in each group). Grafts were stored at 4 degrees C for 24 hours. After transplantation, the right bronchus and pulmonary artery were clamped, and the animals remained dependent on the graft. Posttransplantation graft function was assessed throughout a 7-hour observation period by measuring oxygenation (30-minute intervals), different pulmonary and systemic hemodynamic parameters, and wet/dry lung weight ratios. Bronchoalveolar lavage fluid was obtained before and 2 hours after reperfusion. Surfactant function was measured from bronchoalveolar lavage fluid with a pulsating bubble surfactometer. Neutrophil sequestration was assessed by a myeloperoxidase assay performed on lung tissue specimens taken at the end of the observation period.. Pulmonary vascular resistance remained lower in the iloprost group than in the control group (P < .05). Tissue water content after 7 hours of reperfusion remained lower in the iloprost group (P < .05). In addition, significantly reduced myeloperoxidase tissue activity was observed in the iloprost group (P < .05). Although there was no difference in degradation of surface active surfactant large aggregates to small aggregates, the surface tension measured at minimal bubble diameter was lower in the iloprost group (P < .05).. Modification of low-potassium dextran solution with the prostacyclin analog iloprost resulted in a significant amelioration of ischemia-reperfusion injury and improved preservation of surfactant function in transplanted lungs. This intriguing approach merits further evaluation with respect to the mechanisms involved and, ultimately, potential introduction into clinical lung transplantation.

Topics: Animals; Disease Models, Animal; Female; Graft Rejection; Graft Survival; Iloprost; Lung Transplantation; Male; Organ Preservation; Organ Preservation Solutions; Peroxidase; Probability; Pulmonary Surfactants; Random Allocation; Reference Values; Reperfusion Injury; Sensitivity and Specificity; Surface Tension; Swine

To investigate the effects and mechanisms of ulinastatin on activities of myeloperoxidase (MPO) in lung tissue and neutrophil elastase (NE) in bronchoalveolar lavage fluid and to evaluate the protective effects of ulinastatin on rabbit lung in traumatic hemorrhagic shock.. Thirty rabbits were randomly assigned to three groups: control group, traumatic hemorrhagic shock group and ulinastatin-treatment group. The traumatic hemorrhagic shock model was reproduced by producing: femur fracture and femoral artery bleeding to reduce the mean artery pressure to (40+/-5) mmHg (1 mmHg=0.133 kPa). The hypotension was maintained 90 minutes before the shed blood and equivalent amount of Ringer's lactate was infused. Four hours after blood volume compensation, the activities of MPO in lung tissue and NE in bronchoalveolar lavage fluid (BALF) were measured, and the extravascular lung water volume was determined.. Compared with control group, the activities of either MPO in lung tissue or NE in BALF appeared to be increased in the ulinastatin-treatment group (both P<0.05), but their levels were significantly higher in traumatic hemorrhagic shock group(both P<0.05). The extravascular lung water volume was increased significantly in the two experimental group (both P<0.05), however it was more pronounced in traumatic hemorrhagic shock group (all P<0.05).. Ulinastatin can inhibit the increase in the activities of MPO in lung tissue and NE in BALF, and possesses potential protective effects on the lung tissue in traumatic hemorrhagic shock.

Topics: Animals; Disease Models, Animal; Glycoproteins; Leukocyte Elastase; Lung; Peroxidase; Rabbits; Random Allocation; Reperfusion Injury; Shock, Hemorrhagic; Shock, Traumatic

To investigate the effect of propofol on intercellular adhesion molecular-1 (ICAM-1) expression in the lung tissue following intestinal ischemia/reperfusion (I/R) in rats.. SD rats were randomly divided into 4 groups (n=8 in each group). (1) Group I/R in which rats were subjected to 1 hour of occlusion of the superior mesenteric artery (SMA), followed by 2 hours of reperfusion. (2) Early treatment group (group P1), rats were subjected to the same procedure as group I/R with the additional administration of propofol beginning 10 minutes before ischemia with 10 mg/kg loading dose, followed by continuous infusion at 10 mg(-1).kg(-1).h(-1). (3) Treatment group (group P2), rats were subjected identical insult as in group I/R with the administration of propofol started 10 minutes before reperfusion with 10 mg/kg loading dose, followed by continuous infusion at 10 mg.kg(-1).h(-1). (4) Sham-operation group, rats were subjected to laparotomy only, but received normal saline at 10 ml.kg(-1).h(-1). At the end of reperfusion, all animals were sacrificed. The activity of myeloperoxidase (MPO) and the content of tumor necrosis factor-alpha (TNF-alpha) were determined in the lung tissue, and plasma TNF-alpha content was also quantified. The ICAM-1 expression in pulmonary endothelium was assessed by histochemical staining.. All animals subjected to intestinal I/R demonstrated an increase in TNF-alpha in plasma and lung tissue, MPO activity and ICAM-1 expression in lung tissue. It was much more pronounced in I/R group. Plasma TNF-alpha content was increased significantly in group I/R and P2. All the increase was less in quantity in the early treatment group of propofol than the other two groups, and there was significant difference in contents of plasma TNF-alpha and ICAM-1 expression in lung between group I/R and group P1(both P<0.05).. ICAM-1 plays an important role in lung injury after intestinal I/R. The early treatment of propofol before intestinal I/R may be beneficial by reducing ICAM-1 expression in lung injury.

Topics: Animals; Disease Models, Animal; Female; Intercellular Adhesion Molecule-1; Intestines; Lung Injury; Male; Peroxidase; Propofol; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

This study was designed to examine the effects of aqueous garlic extract (AGE) on hepatic ischaemia-reperfusion (I/R) injury in rats. For this purpose, Wistar albino rats were subjected to 45 min of hepatic ischaemia, followed by a 60-min reperfusion period. AGE (1 mL kg(-1), i. p., corresponding to 500 mg kg(-1)) or saline was administered twice, 15 min before ischaemia and immediately before the reperfusion period. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were determined to assess liver functions. Liver tissues were taken for the determination of malondialdehyde (MDA) levels, an end product of lipid peroxidation; glutathione (GSH) levels, a key antioxidant; and myeloperoxidase (MPO) activity, as an indirect index of neutrophil infiltration. Hepatic collagen content, as a fibrosis marker, was also determined. Plasma ALT and AST activities were elevated in the I/R group as compared with the control group, while these increases were significantly decreased by AGE treatment. Hepatic GSH levels, significantly depressed by I/R, were elevated back to control levels in the AGE-treated I/R group. Increases in tissue MDA levels and MPO activity due to I/R injury were reduced back to control levels by AGE treatment. Similarly, increased hepatic collagen content in the I/R group was reduced to the control level with AGE treatment. Since AGE administration alleviated the I/R-induced injury of the liver and improved the hepatic structure and function, it seems likely that AGE, with its antioxidant and oxidant-scavenging properties, may be of potential therapeutic value in protecting the liver against oxidative injury due to ischaemia-reperfusion.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Collagen; Garlic; Glutathione; Liver; Liver Diseases; Liver Function Tests; Male; Malondialdehyde; Oxidative Stress; Peroxidase; Plant Extracts; Rats; Rats, Wistar; Reperfusion Injury

The role of poly(ADP-ribose) (PAR) glycohydrolase (PARG) in the pathophysiology of renal ischemia/reperfusion (I/R) injury is not known. Poly(ADP-ribosyl)ation is rapidly stimulated in cells after DNA damage caused by the generation of reactive oxygen and nitrogen species during I/R. Continuous or excessive activation of poly(ADP-ribose) polymerase-1 produces extended chains of ADP-ribose on nuclear proteins and results in a substantial depletion of intracellular NAD(+) and subsequently, ATP, leading to cellular dysfunction and, ultimately, cell death. The key enzyme involved in polymer turnover is PARG, which possesses mainly exoglycosidase activity but can remove olig(ADP-ribose) fragments via endoglycosidic cleavage. Thus, the aim of this study was to investigate whether the absence of PARG(110) reduced the renal dysfunction, injury, and inflammation caused by I/R of the mouse kidney. Here, the renal dysfunction and injury caused by I/R (bilateral renal artery occlusion [30 min] followed by reperfusion [24 h]) in mice lacking PARG(110), the major nuclear isoform of PARG, was investigated. The following markers of renal dysfunction and injury were measured: Plasma urea, creatinine, aspartate aminotransferase, and histology. The following markers of inflammation were also measured: Myeloperoxidase activity, malondialdehyde levels, and plasma nitrite/nitrate. The degree of renal injury and dysfunction caused by I/R was significantly reduced in PARG(110)-deficient mice when compared with their wild-type littermates, and there were no differences in any of the biochemical parameters measured between sham-operated PARG(110)(-/-) mice and sham-operated wild-type littermates. Thus, it is proposed that endogenous PARG(110) plays a pivotal role in the pathophysiology of I/R injury of the kidney.

Topics: Animals; Aspartate Aminotransferases; Creatinine; Glycoside Hydrolases; Isoenzymes; Kidney; Male; Mice; Mice, Inbred Strains; Mice, Mutant Strains; Nephritis; Nitrates; Nitrites; Peroxidase; Reperfusion Injury; Urea

Mesenteric venous hypertension and subsequent gut edema play a pivotal role in the development of intra-abdominal hypertension. Although gut edema is one cause of intra-abdominal hypertension, its impact on gut function is unknown. The purpose of this study was to create a model of acute hydrostatic gut edema and to evaluate its effect on gut motility and barrier function.. The first study, group A, evaluated the effect of gut edema on transit over time using 20 mL/kg 0.9% saline. The second study, group B, focused on the 12-hour time period using 80 mL/kg 0.9% saline. Rats were randomized to superior mesenteric vein partial occlusion (venous hypertension) or sham surgery. At 6, 12, and 24 hours, group A underwent intestinal transit and tissue water weight measurements. At 12 hours, group B underwent tissue water, transit, ileal permeability and resistance, lactate and myeloperoxidase activity, and mucosal injury measurements.. Venous hypertension with fluid resuscitation caused acute hydrostatic gut edema, delayed intestinal transit, increased mucosal permeability to macromolecules, and decreased tissue resistance over time. Mucosal injury was minimal in mesenteric venous hypertension.. Acute mesenteric venous hypertension and resuscitation-induced gut edema, in the absence of ischemia/reperfusion injury, is associated with delayed intestinal transit and altered gut barrier function.

Topics: Animals; Disease Models, Animal; Edema; Gastrointestinal Transit; Ileal Diseases; Male; Peroxidase; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Resuscitation; Shock, Hemorrhagic; Sodium Chloride

Intestinal transplantation (ITx) is severely limited by ischemia-reperfusion (I/R) injury. This study investigates I/R injury and ameliorates its consequences by using a recombinant protein targeted against selectins (recombinant P-selectin glycoprotein ligand-immunoglobulin [rPSGL-Ig]).. An isogeneic model of ITx was undertaken with control animals (no therapy) and treatment animals (rPSGL-Ig). Survival was assessed. Separate groups underwent an analysis examining tissue at multiple time points after I/R injury including histopathology; myeloperoxidase staining; immunostaining for CD3 and ED2; polymerase chain reaction analysis of interleukin (IL)-8/cytokine-inducible neutrophil chemoattractant, IL1beta, IL-6, interferon-gamma, IL-2, IL-4, and IL10; and western blots for hemoxygenase-1, BCL-2, and BCL-xl. Standard statistical analysis was undertaken.. Treatment with rPSGL-Ig resulted in significantly improved survival after ITx. Analysis demonstrated diminished injury on histopathology and reduced tissue infiltration of neutrophils and lymphocytes. Significant differences in the cytokine profile after ITx were seen between the two groups including the production of inflammatory cytokines at 24 hr and the Th1 and Th2 cytokines at 2 and 4 hr. Last, treatment resulted in increased production of hemoxygenase, BCL-2, and BCL-xl.. The results of this investigation of I/R injury after ITx revealed that rPSGL-Ig treatment led to marked improvement in outcome. The mechanism of action seems to involve the blockade of neutrophil and lymphocyte infiltration leading to a decreased inflammatory response possibly driven by Th2 cytokines. The results not only lend insight into the mechanisms behind I/R injury after ITx but also demonstrate a potential therapeutic modality to ameliorate its consequences.

Topics: Animals; CD3 Complex; Cytokines; Immunoglobulins; Interleukin-8; Intestines; Male; Membrane Glycoproteins; Neutrophils; P-Selectin; Peroxidase; Rats; Rats, Inbred Lew; Recombinant Fusion Proteins; Reperfusion Injury; RNA, Messenger

Mesenteric ischemia/reperfusion (IR) damages the gastrointestinal epithelia and impairs gut function. Ischemic preconditioning (IPC) has been shown to protect organs against IR injury. We hypothesized that IPC protects the gut from IR injury. Rats were randomized to a sham group, a sham early IPC + IR group (sham IPC + SMA occlusion for 30 min and 6 h of reperfusion), an early IPC + IR group (IPC, three cycles of SMA occlusion for 4 min and reperfusion for 10 min) followed immediately by SMA occlusion for 30 min and 6 h of reperfusion), a sham 24-h group, a sham late IPC + IR group (sham IPC followed by additional reperfusion for 24 h + SMA occlusion for 30 min and 6 h of reperfusion), and a late IPC + IR group (IPC protocol followed by additional reperfusion for 24 h, and then SMA occlusion for 30 min followed by 6 h of reperfusion). At 6 h, transit was determined and expressed as the mean geometric center. Ileum was harvested for assessment of mucosal injury and myeloperoxidase (MPO) activity. Tissue water was determined using the wet-to-dry weight ratio to assess gut edema. Early IPC + IR significantly improved transit (3.9 +/- 0.2), decreased MPO levels (3 +/- 2), and lessened mucosal injury (1.2 +/- 0.3) compared with animals subjected to sham early IPC + IR (transit, 2.9 +/- 0.2; MPO levels, 9 +/- 1; mucosal injury, 3.0 +/- 0.6). Late IPC + IR also improved transit (6.0 +/- 0.4) and decreased MPO levels (1 +/- 1) compared with sham late IPC + IR (transit, 4.4 +/- 0.2; MPO levels, 8 +/- 1), however, there was no difference in the mucosal protection between late IPC + IR (1 +/- 0.3) and sham late IPC + IR (1 +/- 1). Our results suggest that early and late IPC improves intestinal dysfunction, decreases inflammation, and provides mucosal protection in the intestine after IR. Our results show that IR-induced gut dysfunction can be improved by IPC. Both phases of IPC can potentially be useful in the clinical setting of surgical patient care.

Topics: Animals; Digestive System; Edema; Gastrointestinal Transit; Ischemic Preconditioning; Male; Mesenteric Artery, Superior; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Splanchnic Circulation

To investigate the preventive effect of ischemic preconditioning (IPC) on ischemia/reperfusion (I/R)-induced apoptosis and injury in the rat intestine.. We divided 30 male Wistar rats, weighing 300-350 g, randomly into three groups. The control group rats (n = 10) were subjected to laparotomy only; the I/R group (n = 10) rats were subjected to occlusion of the superior mesenteric artery for 45 min, followed by reperfusion for 60 min; and the IPC group (n = 10) rats were subjected to IPC, achieved with two cycles of 5 min ischemia and 5 min reperfusion immediately before the I/R, as in the I/R group. Blood samples were collected by cardiac puncture, to measure nitrate and myeloperoxidase (MPO) levels. Histopathological and immunohistochemical studies were done to evaluate the I/R-induced apoptosis and injury.. The blood MPO and nitrate levels were increased in the I/R group, but IPC prevented their increase. There were significantly fewer apoptotic cells in the IPC group than in the I/R group, and this finding was supported by the caspase-3 expression in the ileum. The intestinal histopathology was also protected by IPC against I/R-induced injury.. Ischemic preconditioning clearly prevented I/R-induced injury and apoptosis by a mechanism related to the caspase-3-dependent pathway. We also showed that IPC inhibited leukocyte activation, with the suppression of myeloperoxidase levels in I/R and nitric oxide-related oxidoinflammatory pathway upregulation.

Topics: Analysis of Variance; Animals; Apoptosis; Biomarkers; Caspase 3; Caspases; Disease Models, Animal; Immunohistochemistry; Intestine, Small; Ischemia; Ischemic Preconditioning; Laparotomy; Male; Peroxidase; Probability; Random Allocation; Rats; Rats, Wistar; Reference Values; Reperfusion Injury; Risk Factors; Sensitivity and Specificity

In recent years it has become increasingly clear that a cross-talk between the inflammatory response and blood coagulation exists, although many of the underlying mechanisms remain unclear. In the present study we investigated the potential anti-inflammatory properties of two different anticoagulant compounds, i.e. active-site inactivated FVIIa (FVIIai) and fondaparinux sodium, a selective FXa inhibitor, administered as pretreatment in a model of intestinal I/R in rats.. Endothelial barrier permeability was assessed using the vascular leakage of radiolabelled human serum albumin, tissue neutrophil sequestration was quantitated by myeloperoxidase (MPO) activity, and plasma levels of macrophage inflammatory protein (MIP)-2 were examined using an enzyme-linked-immuno-sorbent assay after 40 min of intestinal ischaemia and 6 h of reperfusion in the rat (n = 34). Pretreatment with FVIIai or fondaparinux sodium was administered 90 min before initiation of ischaemia.. Endothelial-barrier permeability in all examined organs, myeloperoxidase activity in the lungs, and ileum and MIP-2 levels in plasma increased after intestinal I/R. Pretreatment with FVIIai decreased the endothelial barrier permeability and MPO activity in the ileum, and a tendency towards decreased permeability was also observed in the lungs. Fondaparinux did not affect the endothelial barrier permeability or MPO activity. Both FVIIai and fondaparinux decreased the MIP-2 levels in plasma after intestinal I/R.. Inhibition of the TF-FVIIa complex by FVIIai can attenuate inflammatory responses in connection with intestinal I/R-injury and could represent a potentially important therapeutic strategy for the prevention of organ dysfunction. Potential anti-inflammatory properties of fondaparinux and other inhibitors of FXa are not excluded and need further investigation.

Topics: Animals; Anticoagulants; Blood Cell Count; Cell Membrane Permeability; Chemokine CXCL2; Chemokines, CXC; Endothelium; Factor VIIa; Factor Xa Inhibitors; Fondaparinux; Hemostasis; Intercellular Signaling Peptides and Proteins; Interleukin-8; Intestines; Ischemia; Male; Neutrophil Infiltration; Peroxidase; Polysaccharides; Rats; Rats, Sprague-Dawley; Regional Blood Flow; Reperfusion Injury

The local ischemia-reperfusion (I/R) process gains a systemic nature and affects distal organs. The remote effects of I/R are most frequently observed in the lungs and pulmonary damage may vary from acute lung injury with mild dysfunction to severe respiratory failure or the acute respiratory distress syndrome. In this hind limb I/R induced experimental lung injury model two groups of rats as IR and ILO were determined. Both groups underwent 60 min of ischemia and 120 min of reperfusion. While ILO group received iloprost in saline, IR group received only saline before reperfusion period intravenously. Serum myeloperoxidase (MPO) activity, malondialdehyde (MDA) levels and total antioxidant capacity (TAC) and lung tissue MPO activity, MDA levels and Na+-K+ ATPase activity were measured and light microscopic analyses of lung specimens were performed. The MPO activities in serum and lung homogenates were found to be significantly decreased in ILO group (P < or = 0.01). The MDA levels in lung homogenates were found to be significantly decreased in ILO group (P < or = 0.01), but the decreases were not significant in serum MDA levels (P=0.052). Serum TAC and lung tissue Na+-K+ ATPase activity levels were found to be increased in ILO group compared to IR group (P < or = 0.01). Lung histology showed marked improvement by iloprost compared to the IR group in this study. Iloprost has been found to be effective in attenuating ischemia reperfusion-induced remote organ damage, in this case, lung injury, in rats.

Topics: Acute Disease; Adenosine Triphosphatases; Animals; Antioxidants; Cation Transport Proteins; Hindlimb; Iloprost; Male; Malondialdehyde; Neutrophil Infiltration; Peroxidase; Pulmonary Alveoli; Pulmonary Edema; Rats; Rats, Wistar; Reperfusion Injury; Respiratory Insufficiency; Sodium-Potassium-Exchanging ATPase; Vasodilator Agents

Ischemia/reperfusion (I/R) injury is one of the major obstacles for intestinal transplantation (ITx). Urinary trypsin inhibitor (Ulinastatin, UTI) suppresses proteases and stabilizes lysosomal membranes. We supposed that Ulinastatin would diminish I/R injury of intestinal graft.. UTI- treated group and untreated control group were investigated by histological assessment at 1.5, 4, 24, and 72 h after ITx. Myeloperoxidase (MPO) activity was used as the activity of neutrophils, and malondialdehyde (MDA) was used as an index of lipid peroxidation. TNFalpha and i-NOS mRNA expression in graft tissue were measured by semi-quantitative RT-PCR. CD11b+Gr1+ cells in graft lamina propria were analyzed by flow cytometry.. Histological scores of the graft showed that the tissue injury was markedly attenuated by UTI treatment at different time points after ITx, with reduced MPO and MDA value in the grafts. The expression of TNFalpha and i-NOS mRNA was profoundly inhibited, while the infiltration of CD11b+ Gr1+ cells into the intestinal graft was decreased in UTI group.. Urinary trypsin inhibitor attenuates I/R injury in mouse intestinal transplantation by reducing monocytes infiltration and down-regulation of TNFalpha and i-NOS mRNA expression.

Topics: Animals; CD11b Antigen; Glycoproteins; Intestinal Mucosa; Intestines; Malondialdehyde; Mice; Mice, Inbred BALB C; Monocytes; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Reperfusion Injury; RNA, Messenger; Trypsin Inhibitors; Tumor Necrosis Factor-alpha

Myocardial ischemia-reperfusion (I/R) is associated with the activation of matrix metalloproteinases (MMPs) and serine proteases. We hypothesized that activation of MMPs and the serine protease plasmin contribute to early cardiac myocyte death following I/R and that broad-spectrum protease inhibition with doxycycline (DOX) preserves myocyte viability. Rats treated daily with or without DOX beginning 48 h prior to experimentation were subjected to 30 min of coronary occlusion and 2 days of reperfusion. DOX pre-treatment reduced infarct size by 37%. DOX attenuated increases in MMP-9 and plasmin levels as determined by gelatin zymography and immunoblot, respectively. Neutrophil extravasation was unaltered by DOX as assessed by myeloperoxidase (MPO) activity. To examine the contribution of MMP-9 and plasmin to myocyte injury, cultures of neonatal rat ventricular myocytes (NRVMs) were treated for 48 h with 83 kDa MMP-9 or plasminogen in the presence or absence of DOX. MMP-9 treatment did not affect myocyte viability. Plasminogen treatment led to increased plasmin activity, resulting in loss of beta1-integrin, NRVM detachment and apoptosis. DOX co-treatment inhibited plasmin activity and preserved NRVM attachment, whereas co-treatment with the broad-spectrum MMP inhibitor GM6001 had no effect. These results indicate that plasmin causes disruption of myocyte attachment and viability independently of MMP activation in vitro and that inhibition of plasmin by DOX may reduce I/R-induced myocyte death in vivo through the inhibition of plasmin.

Topics: Animals; Animals, Newborn; Annexin A5; Anti-Bacterial Agents; Apoptosis; Cells, Cultured; Dose-Response Relationship, Drug; Doxycycline; Fibrinolysin; Humans; Immunoblotting; Inflammation; Integrin beta1; Male; Matrix Metalloproteinase 9; Microscopy, Phase-Contrast; Myocardial Infarction; Myocardial Ischemia; Myocardial Reperfusion; Myocardium; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Time Factors; Up-Regulation

Ischemia-reperfusion (IR) injury negatively impacts patient outcome in lung transplantation. Clinically, we observed that lung transplant patients with ischemia-reperfusion injury tend to have cardiac dysfunction. Previous studies have shown that ATL-146e (4-{3-[6-amino-9-(5-ethylcarbamoyl-3,4-dihydroxy-tetrahydro-furan-2-yl)-9H-purin-2-yl]-prop-2-ynyl}-cyclohexanecarboxylic acid methyl ester), a selective adenosine A2A receptor agonist, reduces lung inflammation after ischemia-reperfusion. We hypothesized that pulmonary ischemia-reperfusion causes secondary heart dysfunction and ATL-146e will improve this dysfunction.. We utilized an in vivo rabbit lung ischemia-reperfusion model. The Sham group underwent 120 minutes single lung ventilation. The IR and ATL groups underwent 90 minutes right lung ischemia with 30 minutes right lung reperfusion. The ATL-146e was given intravenously to the ATL group during reperfusion. Cardiac output and arterial blood gases were monitored, and neutrophil sequestration was measured by myeloperoxidase activity.. Upon reperfusion, cardiac output (mL/min) significantly dropped in the IR and ATL groups. By 15 minutes reperfusion, cardiac output in the ATL group improved significantly over the IR group and remained significant thereafter. Lung myeloperoxidase activity was significantly reduced by ATL-146e. Although never hypoxemic, arterial oxygenation was lower in the IR and ATL groups while central venous pressures and mean arterial pressures were similar among groups. A separate experiment demonstrated that reperfusion with the antioxidant N-(2-mercaptopropionyl)glycine prevented cardiac dysfunction.. Pulmonary ischemia-reperfusion causes cardiac dysfunction independent of preload, afterload, and oxygenation. The ATL-146e improves this dysfunction presumably by the antiinflammatory effects of adenosine A2A receptor activation on neutrophils. One likely mechanism involves the release of oxidants from the ischemic lung upon reperfusion, which has immediate negative effects on the heart.

Topics: Adenosine A2 Receptor Agonists; Animals; Antioxidants; Blood Pressure; Cardiac Output; Cyclohexanecarboxylic Acids; Heart; Lung; Neutrophil Activation; Oxygen; Peroxidase; Purines; Rabbits; Reactive Oxygen Species; Reperfusion Injury

We investigated in rats the influence of the lymphatic system and of tumor necrosis factor (TNF) on the lung inflammation resulting from intestinal ischemia/reperfusion (I/R) performed by 45-min occlusion of the superior mesenteric artery followed by 2 h of reperfusion. A group of rats had the thoracic lymph duct ligated before I/R. In lungs, intestinal I/R evoked a significant neutrophil recruitment, and enhanced microvascular permeability, in addition to generation of TNF in serum. In the gut, there was lowered lactate dehydrogenase (LDH) activity and increased microvascular permeability. Upon lymph duct ligation, I/R rats had a significant reduction of pulmonary neutrophil recruitment and plasma extravasation, in addition to high amounts of TNF in the lymph, contrasting with undetectable levels in the serum. In addition, LDH gut levels in these animals were close to basal values; there was also some (yet significant) reduction of microvascular permeability, suggesting that the ligation of the lymphatic duct exerted some degree of protection against the intestinal injury caused by I/R. In I/R rats, the treatment with pentoxifylline (PTX) reduced TNF in serum and blunted other lung alterations. The gut alterations caused by intestinal I/R were largely blocked by PTX. On the other hand, in I/R rats with lymph duct ligation, PTX exacerbated the reduction of pulmonary neutrophil recruitment, but did not affect pulmonary and intestinal microvascular permeabilities. Similarly, intestinal LDH activity and serum TNF levels were unaffected. Overall, our data show that the pulmonary and gut injuries induced by intestinal I/R are partially dependent on TNF, which is conceivably generated in the injured gut tissue due to intestinal I/R and carried by the lymphatic system. Thus, the mesenteric lymphatic drainage seems to play a role as a path modulator of the pulmonary and intestinal dysfunctions that follow a gut trauma.

Topics: Animals; Inflammation; Intestinal Mucosa; Intestines; L-Lactate Dehydrogenase; Lung; Lymph; Lymphatic System; Lymphatic Vessels; Male; Microcirculation; Neutrophils; Pentoxifylline; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Time Factors; Tumor Necrosis Factor-alpha

To investigate the protective efficacy of rabbit endogenous nitric oxide (NO) against acute rabbit lung injury associated with ischemia-reperfusion and explore the possible mechanism.. The rabbit lung ischemia-reperfusion (LIR) model was established; thirty-two adult New Zealand white rabbits were randomly divided into four groups. The rabbits of control group underwent sham operation. In group LIR, the rabbits' left lung hili were clamped for 60 minutes and then released. In group LIR+L-Arg (L-arginine), the rabbits were operated upon as those in group LIR, but L-Arg (200 mg/kg) was infused into blood circulation as substrate for NO generation before removal of the clip. In group LIR+L-NNA (L-ng-nitro-Arginine), the rabbits passed through the same operation as in group LIR, but L-NNA (10 mg/kg) was infused into circulation as an inhibitor against NO generation before reperfusion. After reperfusion for 60 minutes, the lung tissues were harvested for histological examination, and the wet to dry ratio of lung tissue weight (W/D), myeloperoxidase (MPO) activity, malondialdehyde (MDA) content as well as the ratio of nitrate/nitrite (N/N) were measured respectively.. The group LIR had greater lung tissue W/D, higher MPO activity and MDA content, lower ratio of N/N, and serious pulmonary edema as compared with group ShO (P<0.01). But in group LIR+L-Arg, the degree of pulmonary edema was alleviated, the MPO activity and MDA content were decreased, and the ratio of N/N increased; there was statistically significant difference between group LIR and group LIR+Arg in respect to the above indices (P<0.01). However, in group LIR+L-NNA, the pulmonary edema was even more severe, the MPO activity and MDA content were significantly higher those that in group LIR or group LIR+L-Arg (P<0.01).. The endogenous release of pulmonary NO can attenuate the acute lung injury associated with LIR, and the mechanisms may involve the protective efficacy conferred by endogenous NO against accumulation of neutrophil in lung, against pulmonary microvascular permeability, and against the oxygen free radical injury to lung.

Topics: Animals; Lung; Malondialdehyde; Nitric Oxide; Peroxidase; Rabbits; Random Allocation; Reperfusion Injury

Reperfusion injury continues to significantly affect patients undergoing lung transplantation. Isolated lung models have demonstrated that adenosine A 2A receptor activation preserves function while decreasing inflammation. We hypothesized that adenosine A 2A receptor activation by ATL-146e during the initial reperfusion period preserves pulmonary function and attenuates inflammation in a porcine model of lung transplantation.. Mature pig lungs preserved with Viaspan (Barr Laboratories, Pomona, NY) underwent 6 hours of cold ischemia before transplantation and 4 hours of reperfusion. Animals were treated with (ATL group, n = 7) and without (IR group, n = 7) ATL-146e (0.05 microg kg -1 . min -1 ATL-146e administered intravenously for 3 hours). With occlusion of the opposite pulmonary artery, the animal was maintained for the final 30 minutes on the allograft alone. Recipient lung physiology was monitored before tissue evaluation of pulmonary edema (wet-to-dry weight ratio), myeloperoxidase assay, and tissue tumor necrosis factor alpha by means of enzyme-linked immunosorbent assay.. When the ATL group was compared with the IR group, the ATL group had better partial pressure of carbon dioxide (43.8 +/- 4.1 vs 68.9 +/- 6.3 mm Hg, P < .01) and partial pressure of oxygen (272.3 +/- 132.7 vs 100.1 +/- 21.4 mm Hg, P < .01). ATL-146e-treated animals exhibited lower pulmonary artery pressures (33.6 +/- 2.1 vs 47.9 +/- 3.5 mm Hg, P < .01) and mean airway pressures (16.25 +/- 0.08 vs 16.64 +/- 0.15 mm Hg, P = .04). ATL-146e-treated lungs had lower wet-to-dry ratios (5.9 +/- 0.39 vs 7.3 +/- 0.38, P < .02), lower myeloperoxidase levels (2.9 x 10 -5 +/- 1.2 x 10 -5 vs 1.3 x 10 -4 +/- 4.0 x 10 -5 DeltaOD mg -1 . min -1 , P = .03), and a trend toward decreased lung tumor necrosis factor alpha levels (57 +/- 12 vs 96 +/- 15 pg/mL, P = .06). The ATL group demonstrated significantly less inflammation on histology.. Adenosine A 2A activation during early reperfusion attenuated lung inflammation and preserved pulmonary function in this model of lung transplantation. ATL-146e and similar compounds could play a significant role in improving outcomes of pulmonary transplantation.

Topics: Adenosine A2 Receptor Agonists; Animals; Blood Gas Analysis; Carbon Dioxide; Cyclohexanecarboxylic Acids; Disease Models, Animal; Drug Evaluation, Preclinical; Enzyme-Linked Immunosorbent Assay; Female; Inflammation; Lung; Lung Transplantation; Male; Neutrophil Activation; Organ Size; Oxygen; Peroxidase; Pulmonary Edema; Purines; Random Allocation; Receptor, Adenosine A2A; Reperfusion Injury; Respiratory Function Tests; Severity of Illness Index; Swine; Time Factors; Tumor Necrosis Factor-alpha

Complement activation plays an important role in local and remote tissue injury associated with gastrointestinal ischemia-reperfusion (GI/R). The role of the classical and lectin complement pathways in GI/R injury was evaluated using C1q-deficient (C1q KO), MBL-A/C-deficient (MBL-null), complement factor 2- and factor B-deficient (C2/fB KO), and wild-type (WT) mice. Gastrointestinal ischemia (20 min), followed by 3-h reperfusion, induced intestinal and lung injury in C1q KO and WT mice, but not in C2/fB KO mice. Addition of human C2 to C2/fB KO mice significantly restored GI/R injury, demonstrating that GI/R injury is mediated via the lectin and/or classical pathway. Tissue C3 deposition in C1q KO and WT, but not C2/fB KO, mice after GI/R demonstrated that complement was activated in C1q KO mice. GI/R significantly increased serum alanine aminotransferase, gastrointestinal barrier dysfunction, and neutrophil infiltration into the lung and gut in C1q KO and WT, but not C2/fB KO, mice. MBL-null mice displayed little gut injury after GI/R, but lung injury was present. Addition of recombinant human MBL (rhuMBL) to MBL-null mice significantly increased injury compared with MBL-null mice after GI/R and was reversed by anti-MBL mAb treatment. However, MBL-null mice were not protected from secondary lung injury after GI/R. These data demonstrate that C2 and MBL, but not C1q, are necessary for gut injury after GI/R. Lung injury in mice after GI/R is MBL and C1q independent, but C2 dependent, suggesting a potential role for ficolins in this model.

Topics: Alanine Transaminase; Animals; Complement C1q; Complement C2; Complement C3; Complement Pathway, Classical; Complement Pathway, Mannose-Binding Lectin; Dextrans; Fluorescein-5-isothiocyanate; Gastrointestinal Tract; Humans; Intestines; Lung; Male; Mannose-Binding Lectins; Mice; Mice, Inbred C57BL; Mice, Knockout; Microscopy, Confocal; Permeability; Peroxidase; Reperfusion Injury

There is increasing evidence to suggest that reactive oxygen metabolites (ROMs) play a role in the pathogenesis of ischemia/reperfusion injury (I/R) in the kidney. This study was designed to determine the possible protective effect of Ginkgo biloba extract (EGb) on renal ischemia/reperfusion (I/R) injury. Wistar albino rats were unilaterally nephrectomized, and 15 days later they were subjected to 45 min of renal pedicle occlusion followed by 6 h of reperfusion. Ginkgo biloba extract (EGb) (50 mg kg(-1) day(-1)) or saline was administered twice, 15 min prior to ischemia and immediately before the reperfusion period. At the end of the treatment period, all rats were decapitated. Kidney samples were taken for histological examination or determination of the renal malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and collagen content. Production of reactive oxidants was monitored by chemiluminescence (CL) assay. Creatinine and urea concentrations in blood were measured for the evaluation of renal function. Tumor necrosis factor-alpha (TNF-alpha) and lactate dehydrogenase (LDH) were also assayed in serum samples. Ischemia/reperfusion caused a significant decrease in GSH level, which was accompanied with significant increases in MDA level, MPO activity and collagen content of kidney tissues. Similarly, serum BUN and creatinine levels, as well as LDH and TNF-alpha, were elevated in the I/R group as compared to control group. On the other hand, EGb treatment reversed all these biochemical indices, as well as histopathological alterations, which were induced by I/R. The findings imply that ROMs play a causal role in I/R-induced renal injury and EGb exerts renoprotective effects probably by the radical scavenging and antioxidant activities.

Topics: Acridines; Animals; Blood Urea Nitrogen; Collagen; Creatinine; Ginkgo biloba; Glutathione; Kidney; Kidney Diseases; L-Lactate Dehydrogenase; Luminol; Male; Malondialdehyde; Oxidative Stress; Peroxidase; Plant Extracts; Protective Agents; Rats; Rats, Wistar; Reperfusion Injury

The aim of this study was to determine whether nuclear factor-kappaB (NF-kappaB) inhibitors are efficient against hepatic ischemia/reperfusion (I/R) injury. We previously demonstrated that xanthine oxidase-derived reactive oxygen species activate NF-kappaB during ischemia. However, the role of NF-kappaB activation during ischemia in post-reperfusion injury remains unclear. Therefore, while we examined the effects of NF-kappaB inhibitors, sulfasalazine and pyrrolidinedithiocarbamate on hepatic I/R injury using a rat lobar hepatic I/R model, we estimated the relationship between NF-kappaB activation during ischemia and following hepatic damage caused by reperfusion. The portal vein and the hepatic artery were clamped for 1 hr followed by reperfusion for up to 24 hr. NF-kappaB activation was determined by Western blot analysis. NF-kappaB activation was observed in the ischemic lobe of the liver, and the activation was prevented by pre-administration with NF-kappaB inhibitors. Although the serum ALT level, hepatic MPO activity and BSP clearance, as an index of hepatic injury, were increased after reperfusion, the increase was attenuated by pre-administration with NF-kappaB inhibitors. These findings suggest that NF-kappaB activation during ischemia is relevant to hepatic I/R injury. Moreover, we first showed that pre-administration with NF-kappaB inhibitors is effective against hepatic I/R injury.

Topics: Alanine Transaminase; Animals; Ischemia; Liver; Male; NF-kappa B; Peroxidase; Proline; Rats; Rats, Wistar; Reperfusion Injury; Sulfobromophthalein; Thiocarbamates

Lung transplantation has evolved to become an effective treatment for a variety of end-stage lung diseases. However, severe reperfusion injury is still a major cause for postoperative morbidity and mortality. Although lung reperfusion injury is complex and has not been fully comprehended yet, neutrophil infiltration and cytokine activation have been postulated to play a main role. Recent studies showed that nitric oxide (NO) therapy has salutary effects on lung chronic and acute pathologies because it inhibits interleukin-8 (IL-8) release, but no data have been found on its effects during organ harvest. The aim of this study was to assess whether low doses of inhaled NO pre-treatment at the time of harvesting improves allograft function during early reperfusion in a porcine model.. Twenty-two Landrace pigs were randomly assigned to NO-treated and control groups. In NO-treated pigs, NO at 20 ppm was administered 30 min before harvest. During the early allograft reperfusion period IL-8 content, dynamic and static compliance and gas exchange (Pa/FiO2 and PaO2) were measured in both control and NO-treated lungs.. Pre-treatment with NO at the time of harvesting showed improvement of allograft function in terms of dynamic (92 +/- 8% in NO vs 72 +/- 7% in the control group, p < .05) and static (83 +/- 8% in NO vs 63 +/- 7% in the control group, p < 0.05) compliance and gas exchange (PaO2: 96 +/- 4% in NO vs 74 +/- 4.5% in the control group, p < 0.01; Pa/FiO2: 97 +/- 5% in NO vs 74 +/- 5% in the control group, p < 0.01) by diminishing IL-8 (66.5 +/- 4.7 pg/ml in NO versus 208 +/- 43 pg/ml in the control group, p < 0.05) release in pigs.. These results show for the first time that NO pre-treatment at the time of harvesting reduces allograft reperfusion injury in part due to its effects on IL-8 release.

Topics: Administration, Inhalation; Animals; Dose-Response Relationship, Drug; Drug Administration Schedule; Endothelium-Dependent Relaxing Factors; Interleukin-8; Lung; Lung Transplantation; Models, Animal; Nitric Oxide; Peroxidase; Premedication; Reperfusion Injury; Swine

Renal impairment is a very frequent complication of aortic surgery requiring prolonged suprarenal clamping, especially if it is associated with previous hemorrhage. The aim of this study was to assess the beneficial effect of the administration of a nitric oxide (NO) donor on renal function through a modulation of the systemic inflammatory response in a model of abdominal aortic surgery.. Twenty-five minipigs were divided into five groups. Under anesthesia, the animals were subjected to suprarenal aortic-iliac clamping (for 30 minutes) and bypass with a Dacron-collagen prosthetic graft impregnated in rifampicin, with or without associated hemorrhage (40% of total blood volume). Prophylaxis with cefazolin was implemented. The five groups were (1) the sham group (only aortic dissection), (2) the clamping and bypass (C) group, (3) hemorrhage preclamping and bypass (H+C) group, (4) the same as group C but with the administration of the NO donor molsidomine (4 mg/kg intravenously) (C+NO group), (5) the same as the H+C group but with the administration of the NO donor molsidomine (4 mg/kg intravenously) (H+C+NO group). The following were determined: (1) kidney function (serum creatinine), (2) serum cytokines (tumor necrosis factor alpha [TNF-alpha] and interleukin-10 [IL-10]); (3) neutrophil infiltration (myeloperoxidase [MPO]) in the kidney, (4) oxygen free radicals (superoxide anion [SOA] and superoxide dismutase [SOD]) in the kidney, (5) serum nitrites, (6) soluble and kidney tissue cell adhesion molecule (soluble intercellular adhesion molecule-1 [sICAM-1], soluble vascular cell adhesion molecule-1 [sVCAM-1], intercellular adhesion molecule-1 [ICAM-1], and vascular cell adhesion molecule-1 [VCAM-1]), (7) inducible nitric oxide synthase (iNOS) in the kidney, and (8) nuclear factor-kappaB (NF-kappaB) in the kidney. Determinations were made during ischemia at 15 minutes post-reperfusion; at 24, 48, and 72 hours; and on day 7.. The different insults used in the experimental model led to deterioration in kidney function and an increase in the systemic (and renal) inflammatory response at all levels investigated. Treatment with an NO donor, both with and without associated hemorrhage, reduced the inflammatory response at the systemic (TNF-alpha and IL-10) and kidney (MPO, SOA, and SOD) levels, normalizing kidney function. Likewise, exogenous administration of NO improved the excessive production of NO (nitrites) via iNOS. This was also reflected in a reduction in CAMs and of NF-kappaB expression. The hypotension induced by molsidomine was transitory and did not elicit hemodynamic repercussions.. In our experimental model, prophylactic treatment with the NO donor molsidomine regulates the systemic inflammatory response and minimizes damage at the kidney level. Clinical Relevance The importance of this article resides in the fact that an experimental study that clarifies the effect of the donors of NO under circumstances as similar as possible to those of the human clinic, such as aortic surgery under hypovolemic shock (ruptured aortic aneurysm) have been little studied, most of these studies being performed in rodents without bypass. Using a model with one or two simultaneous insults (aortic clamping with/without previous hemorrhage) that is very similar to the human clinical situation (abdominal aortic rupture), we confirm the findings of previous work related to the beneficial effects of NO donors.

Topics: Animals; Aortic Aneurysm, Abdominal; Creatinine; Disease Models, Animal; Intercellular Adhesion Molecule-1; Interleukin-10; Kidney; Leukocytes; Male; Molsidomine; NF-kappa B; Nitric Oxide Donors; Peroxidase; Reperfusion Injury; Swine; Swine, Miniature; Systemic Inflammatory Response Syndrome; Tumor Necrosis Factor-alpha; Vascular Cell Adhesion Molecule-1

Reperfusion of an ischaemic tissue is associated with an intense inflammatory response and inflammation-mediated tissue injury. Physalins, a group of substances with secosteroidal chemical structure, are found in Physalis angulata stems and leaves. Here, we assessed the effects of physalins on the local, remote and systemic injuries following intestinal ischaemia and reperfusion (I/R) in mice and compared with the effects of dexamethasone. Following I/R injury, dexamethasone (10 mg kg(-1)) or physalin B or F markedly prevented neutrophil influx, the increase in vascular permeability in the intestine and the lungs. Maximal inhibition occurred at 20 mg kg(-1). Moreover, there was prevention of haemorrhage in the intestine of reperfused animals. Dexamethasone or physalins effectively suppressed the increase in tissue (intestine and lungs) and serum concentrations of TNF-alpha. Interestingly, treatment with the compounds was associated with enhancement of IL-10. The anti-inflammatory effects of dexamethasone or physalins were reversed by pretreatment with the corticoid receptor antagonist RU486 (25 mg kg(-1)). The drug compounds suppressed steady-state concentrations of corticosterone, but did not alter the reperfusion-associated increase in levels of corticosterone. The IL-10-enhancing effects of the drugs were not altered by RU486. In conclusion, the in vivo anti-inflammatory actions of physalins, natural steroidal compounds, appear to be mostly due to the activation of glucocorticoid receptors. Compounds derived from these natural secosteroids may represent novel therapeutic options for the treatment of inflammatory diseases.

Topics: Animals; Anti-Inflammatory Agents; Anti-Inflammatory Agents, Non-Steroidal; Capillary Permeability; Chemokines; Cytokines; Dexamethasone; Dose-Response Relationship, Drug; Gastrointestinal Hemorrhage; Glucocorticoids; Hemoglobins; Intestinal Diseases; Lactones; Male; Mice; Mice, Inbred C57BL; Peroxidase; Reperfusion Injury; Secosteroids; Steroids

To investigate the effects of nitric oxide (NO) on reperfusion injury following pancreaticoduodenal transplantation in rats.. The homologous male Wistar rat model of heterotopic total pancreaticoduodenal transplantation was used. The L-arginine (L-Arg) group received intravenous injection of L-Arg 5 minutes before and after reperfusion at a dose of 200 mg/kg while the N-Nitro-L-Arginine methyl ester (L-NAME) group received intravenous injection of L-NAME at a dose of 10 mg/kg, and control group received saline. The amount of NO in the pancreas graft was measured. Serum concentration of cytokine-induced neutrophil chemoattractant (CINC) determined by enzyme-linked immunosorbant assay, expression of CINC mRNA detected by Northern blot assay, and myeloperoxidase (MPO) activity in the pancreas graft were measured. Histological observation was performed.. The amount of NO in the L-Arg group was higher than in the control group, while in the L-NAME group was lower than in the control group (P < 0.05). The peak of serum CINC concentration occurred 3 hours after reperfusion with significant difference among groups. Expression peak of CINC mRNA in the pancreas graft occurred 3 hours after reperfusion. The expression level in the L-Arg group was lower than in the control group, the L-NAME group was higher than control group (P < 0.05). MPO activity in the L-Arg group obviously decreasd compared with other groups. The pancreas inflammation was ameliorated in L-Arg group, and pancreas damage was aggravated in L-NAME group.. L-Arg can increase the amount of NO and inhibit the elevation of CINC, CINC mRNA expression, and early neutrophil accumulation in the transplanted pancreas. NO has protective effects on the ischemia/reperfusion injury of pancreaticoduodenal transplantation.

Topics: Animals; Arginine; Chemokines, CXC; Duodenum; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide; Pancreas Transplantation; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; RNA, Messenger

Topics: Animals; Blood Coagulation Tests; Liver; Male; NF-kappa B; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; RNA, Messenger; Thromboplastin

Anti-inflammatory action of Antithrombin III (AT III) is still not well understood in ischemia/reperfusion (I/R) injury. In the present study, we aimed to investigate the anti-inflammatory action of AT III on remote lung and local skeletal muscle tissue injury in a rat model of bilateral lower limb I/R model.. Bilateral lower limb ischemia and reperfusion were produced by means of tourniquets occlusions and releases, respectively. Three groups of rats were used in this controlled study: sham group (sham, n=3) underwent 5 h of anesthesia only; control group (I/R, n=7) underwent 3 h of bilateral lower limb ischemia followed by 2 h of reperfusion; and AT III pretreated group (I/R-AT III, n=6) underwent the same procedure as the control group, but also received i.v. 250 U kg-1 AT III 30 min before ischemia induction under midazolam and fentanyl anesthesia.. Lung and muscle tissue accumulation of polymorphonuclear leukocytes (PMN) were assessed by measuring tissue myeloperoxidase (MPO) activity. Histopathological changes in tissues were assessed by PMN counts in the lung, and muscle tissues and by histological lung injury score. Plasma 6-keto prostaglandin F(1alpha) and tumor necrosis factor alpha levels were measured by an enzyme immunoassay technique. Myeloperoxidase activity could not be detected in the muscle tissues of all groups. The lung and muscle tissue PMN counts in the I/R group were significantly higher compared with the I/R-AT III group (P<0.05).. Data from the present study provides some evidence that AT III pretreatment attenuates remote lung and local skeletal muscle tissue injury caused by lower limb I/R.

Topics: 6-Ketoprostaglandin F1 alpha; Animals; Anticoagulants; Antithrombin III; Disease Models, Animal; Ischemia; Ischemic Preconditioning; Lower Extremity; Lung; Muscle, Skeletal; Neutrophil Infiltration; Neutrophils; Peroxidase; Pilot Projects; Rats; Rats, Wistar; Reperfusion; Reperfusion Injury; Tumor Necrosis Factor-alpha

It was demonstrated that xanthine oxidoreductase (XOR), during ischemia, catalyzes the formation of nitric oxide (NO) from nitrite (NO2-) and this NO2- -derived NO protects the isolated perfused rat heart against the damaging effects of ischemia-reperfusion (I/R) when conventional nitric oxide synthase (NOS)-dependent NO production is impaired. Liver is one of the organs with the highest XOR concentration. This study was designed to determine whether NO2- -derived NO by XOR protects liver against I/R injury in vivo. For its minute amounts and active reactivity, NO can not be detected directly in real time in vivo by this time. We have to prove the above hypothesis indirectly.. Wistar rats were pretreated with saline, NOS inhibitor L-NAME (10 mg/kg intravenously), XOR inhibitor allopurinol (1.5 mg/kg orally), L-NAME +allopurinol and NO scavenger carboxy-PTIO (0.6 mg/kg intravenously) respectively (12 animals per group). And then, they were subjected to total liver ischemia for 40 minutes followed by reperfusion. Blood samples and liver tissues were obtained for analysis after 3 hours of reperfusion. Survival was also investigated.. Allopurinol-treated animals exhibited further increased serum alanine aminotransferase(ALT) levels and liver myeloperoxidase(MPO) activities, but further decreased liver adenosine triphosphate(ATP) stores after I/R compared to saline-treated counterparts (830.5+/-108.3 U/L, 56.5+/-11.0 U/mg protein and 1.93+/-0.47 mumol/g vs. 505.8+/-184.2 U/L, 41.5+/-10.2 U/mg protein and 3.05+/-0.55 micromol/g respectively, P < 0.01, P < 0.05 and P < 0.01 respectively). The hepatocyte injury was further exacerbated and the overall survival rate was significantly decreased after I/R in animals given by allopurinol compared to those pretreated by saline (P < 0.05). L-NAME and allopurinol co-treated animals exhibited more severe liver injury (P < 0.05 and P<0.01)and a further decreased overall survival rate (P < 0.05)compared to L-NAME or allopurinol alone-treated counterparts, but they were not different from carboxy-PTIO treated animals (P > 0.05).. NO2- -derived NO by XOR in the hypoxic and acidic environment induced by hepatic I/R protects the liver against I/R injury in vivo.

Topics: Adenosine Triphosphate; Alanine Transaminase; Allopurinol; Animals; Enzyme Inhibitors; Female; Liver; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase; Nitrites; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Survival Analysis; Xanthine Dehydrogenase

To investigate the effect of 17beta-estradiol (E2) on ischemia-reperfusion (I/R) injury in diabetic ovariectomized female rats. Streptozotocin(STZ)-induced diabetic female rats received E2 treatment for 2 weeks after ovariectomy (OVX). A period of 90 min of temporary middle cerebral artery occlusion (tMCAO) was used for the study. Rats were evaluated for physiological data including plasma glucose, E2, MAP, PaCO2 and PaO2 before and after tMCAO. P-selectin expression, myeloperoxidase (MPO) enzyme activity and the cerebral infarct volume were analyzed.. The infarct volume in the E2-treated OVX rats is bigger than that in intact and OVX groups. However, there is not a significant different area of cerebral infarct between diabetic OVX and intact rats. Significant upregulation of P-selectin expression and MPO activity of the ischemia-reperfusion hemisphere were observed in E2 + OVX, intact and OVX groups at 8, 24, 72 h in time manner after tMCAO compared with that of the contralateral hemisphere of cerebral ischemia-reperfusion. Both P-selectin expression and MPO activity in the E2 + OVX and intact rats are significantly higher than that in the untreated OVX rats. Chronic estrogen replacement therapy (ERT) potentiates the I/R injury in diabetes female rats. This may be related to the increased expression of P-selectin and MPO activity.

Topics: Analysis of Variance; Animals; Blood Glucose; Blotting, Western; Body Weight; Brain Infarction; Diabetes Mellitus, Experimental; Estradiol; Female; Gene Expression Regulation; Ovariectomy; P-Selectin; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Time Factors

To investigate the effect of Panax notoginseng saponins (Pns) on the expression of intercellular adhesion molecule-1 (ICAM-1) and brain neutrophil infiltration induced by transient focal cerberal ischemia and reperfusion in rats.. Focal cerebral ischemia-reperfusion model in rats (male) were made by transient occlusion of the middle cerebral artery (MCA) for 2 h followed by 24 h reperfusion. Pns 25 and 50 mg/kg were administered ip at 2 h after reperfusion. At 24 h after reperfusion, neutrophil infiltration and the expression of intercellular adhesion molecule-1 (ICAM-1) were measured with myeloperoxidase (MPO) activity, and immunohistochemistry, respectively.. After ischemia reperfusion, the expression of ICAM-1 and MPO activity in the ischemic hemisphere cortex of MCA area and caudate putamen were markedly increased. Treatment with 50 mg/kg Pns inhibited neutrophil infiltration and the expression of ICAM-1.. Pns inhibited neutrophil infiltration and the expression of ICAM-1 following focal cerebral ischemia-reperfusion in rats, attenuated the ischemic brain inflammation.

Topics: Animals; Cerebral Infarction; Ginsenosides; Intercellular Adhesion Molecule-1; Male; Neutrophil Infiltration; Panax; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Pretreatment with thaliporphine before ischemia affords cardioprotective effects against reperfusion injury via antioxidant activity. This study evaluated whether thaliporphine administered at a certain period after myocardial ischemia conferred the same cardioprotection and assessed its possible new mechanism. The left main coronary artery of anaesthetized rats was occluded for 1 h and then reperfused for 2 h. Thaliporphine was administered at 10 min before reperfusion. Controls received saline only. Morphine, a nonselective opioid receptor agonist, was used as reference compound at 0.3 mg/kg. Thaliporphine at 0.05 and 0.5 mg/kg were found to reduce the infarct size. Recovery of cardiac function was higher in thaliporphine (0.5 mg/kg) group, as assessed by a significant improvement in the rates of pressure development (+dp/dt (max)). This compound also reduced plasma creatine kinase and cardiac MPO activity. These protective effects afforded by thaliporphine were diminished by the opioid receptor antagonists (naloxone or naltrexone) and by the mitochondrial K(ATP) blocker 5HD. In comparison, morphine reduced infarct size and MPO activity in the myocardium but produced slightly improvement in cardiac function after ischemia-reperfusion. These results demonstrate that reperfusion therapy with thaliporphine protect cardiac injury through further mechanism via activation of opioid receptor and opening of mitochondrial K(ATP) channels as morphine but with stronger activity.

Topics: Adenosine Triphosphate; Analgesics, Opioid; Animals; Antioxidants; Aporphines; Creatine Kinase; Dose-Response Relationship, Drug; Heart; Male; Mitochondria; Morphine; Myocardial Ischemia; Myocardium; Naloxone; Naltrexone; Narcotic Antagonists; Peroxidase; Plant Extracts; Potassium; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Risk; Time Factors

Oxygen free radicals are considered to be important components involved in the pathophysiological tissue alterations observed during ischemia/reperfusion (I/R). Based on the potent antioxidant effects of melatonin, we investigated the putative protective role of melatonin against I/R-induced oxidative remote organ injury.. Wistar albino rats were subjected to 1 h of infrarenal aortic occlusion followed by 1 h of reperfusion to induce I/R damage. Melatonin (10 mg/kg, s.c.) or vehicle was administered twice, 15 min prior to ischemia and immediately before the reperfusion period (I/R + Mel or I/R groups). At the end of the reperfusion periods, the rats were decapitated and hepatic, ileal, and lung tissue samples were removed for biochemical analyses of: malondialdehyde (MDA), an end product of lipid peroxidation; the glutathione (GSH) levels, a key antioxidant; and the myeloperoxidase (MPO) activity, as an indirect index of neutrophil infiltration. The serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were measured to evaluate the liver function. The wet/dry lung weight ratio was calculated to determine the extent of lung damage.. The results revealed the occurrence of I/R-induced oxidative organ damage, as evidenced by increases in the MDA and MPO activity, and a decrease in GSH. Furthermore the AST, ALT levels, and the wet/dry lung weight ratio, which all increased due to I/R, were all observed to decrease after melatonin treatment.. Since melatonin administration reversed these oxidant responses, it seems likely that melatonin has a protective effect against oxidative organ damage induced by I/R.

Topics: Animals; Antioxidants; Aorta, Abdominal; Glutathione; Ligation; Lipid Peroxidation; Liver Function Tests; Melatonin; Neutrophil Infiltration; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Oxidative stress results from an oxidant/antioxidant imbalance, an excess of oxidants, and/or a depletion of antioxidants. A considerable body of recent evidence suggests that oxidative stress and exaggerated production of reactive oxygen species play a major role in several aspects ischemia and reperfusion. Hypericum perforatum is a medicinal plant species containing many polyphenolic compounds, namely flavonoids and phenolic acids. Because polyphenolic compounds have high antioxidant potential, in this study we evaluated the effect of H. perforatum extract on splanchnic artery occlusion (SAO) shock-mediated injury. SAO shock was induced in rats by clamping the superior mesenteric artery and the celiac trunk for 45 min. After 1 h of reperfusion, SAO-shocked rats developed a significant fall in mean arterial blood pressure. Treatment of rats with H. perforatum extract (applied at 25 mg/kg 15 min before reperfusion) significantly reduced a significant fall in mean arterial blood pressure and the migration of polymorphonuclear cells caused by SAO-shock. H. perforatum extract also attenuated the ileum injury (histology) as well as the increase in the tissue levels of myeloperoxidase and malondialdehyde caused by SAO shock in the ileum. Immunohistochemical analysis for nitrotyrosine and for poly ADP-ribosylated proteins revealed a positive staining in ileum from SAO-shocked rats. The degree of staining for nitrotyrosine and poly ADP-ribosylated proteins was markedly reduced in tissue sections obtained from SAO-shocked rats that had received H. perforatum extract. Reperfused ileum tissue sections from SAO-shocked rats showed positive staining for P-selectin and for intercellular adhesion molecule-1 in the vascular endothelial cells. H. perforatum extract treatment markedly reduced the intensity and degree of P-selectin and intercellular adhesion molecule-1 in tissue section from SAO-shocked rats. H. perforatum extract treatment significantly improved survival. In conclusion, this study demonstrates that H. perforatum extract exerts multiple protective effects in splanchnic artery occlusion-reperfusion shock and suggests that H. perforatum extract may be a candidate for consideration as a therapeutic intervention for ischemia-reperfusion injury.

Topics: Animals; Antioxidants; Blood Pressure; Cytokines; Densitometry; Flavonoids; Hydroxybenzoates; Hypericum; Immunohistochemistry; Intercellular Adhesion Molecule-1; Lipid Peroxidation; Male; Malondialdehyde; Mesenteric Artery, Superior; Neutrophils; P-Selectin; Peroxidase; Phenols; Phytotherapy; Plant Extracts; Poly(ADP-ribose) Polymerases; Polyphenols; Random Allocation; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Reperfusion Injury; Shock; Time Factors; Treatment Outcome; Tyrosine

Activated leukocytes are implicated in development of ischemia/reperfusion (I/R)-induced organ injuries. Phosphodiesterase 3 inhibitors have anti-inflammatory effects by preventing cyclic adenosine monophosphate (cAMP) degradation. We examined the effects of olprinone, a specific phosphodiesterase 3 inhibitor, on I/R-induced acute renal injury model in rats. Forty-five minute renal I/R was induced in uni-nephrectomized rats. Rats were divided into a vehicle group, an olprinone group, and a dibutyril (DB) cAMP group. Olprinone (0.2 microg/kg/minute) infusion began 30 min after reperfusion and continued for 3 h. DBcAMP (5 mg/kg), a stable analog of cAMP, was intraperitoneally administered 5 min after reperfusion to clarify the effect of cAMP in our model. Olprinone reduced the I/R-induced increases in serum levels of blood urea nitrogen and creatinine, and improved histological changes, including acute tubular necrosis in the outer medulla. Hemodynamic status was not affected by olprinone. I/R-induced a decrease in renal tissue blood flow, an increase in renal vascular permeability, and an enhancement of leukocyte activation, reflected by renal tissue levels of myeloperoxidase activity, and the tissue levels of cytokine-induced neutrophil chemoattractant (an equivalent of human interleukin 8) and tumor necrosis factor-alpha were all significantly decreased by olprinone. Olprinone also increased the renal tissue and plasma levels of cAMP in rats subjected to renal I/R. DBcAMP showed similar effects. Our results indicated that olprinone reduced the I/R-induced acute renal injury, probably by inhibiting leukocyte activation. The effects of olprinone could be explained through its action on cAMP levels.

Topics: Animals; Blood Urea Nitrogen; Cardiotonic Agents; Creatinine; Cyclic AMP; Hemodynamics; Imidazoles; Inflammation; Interleukin-8; Kidney; Leukocytes; Lymphocyte Activation; Male; Necrosis; Neutrophils; Peroxidase; Phosphodiesterase Inhibitors; Pyridones; Rats; Rats, Wistar; Reperfusion Injury; Time Factors; Tumor Necrosis Factor-alpha

Flush perfusion with low-potassium dextran is the standard strategy in clinical lung preservation. Despite improved outcome, endothelial cell injury and surfactant dysfunction remain a significant problem after lung transplantation. The radical scavenger glutathione has been shown to be responsible for the efficacy of Celsior solution in lung preservation. We tested the hypothesis that the addition of glutathione to low-potassium dextran might further improve graft function by ameliorating ischemia-reperfusion injury.. In 12 domestic pigs, lungs were flush preserved with either low-potassium dextran (n = 6) or low-potassium dextran supplemented by 5 mmol glutathione (n = 6). Left single lung transplantation was performed after 24-hour storage in low-potassium dextran at 8 degrees C. After 15 minutes of reperfusion the right main bronchus and pulmonary artery were crossclamped. Hemodynamic and respiratory measures were recorded in 30-minute intervals for a total observation period of 7 hours. Bronchoalveolar lavage fluid was obtained from the native lung and 2 hours after reperfusion from the graft. Bronchoalveolar lavage fluid and surfactant composition, and surfactant function analyses were performed. Neutrophil sequestration was assessed by myeloperoxidase activity assay. Tissue water content was calculated from wet/dry weight ratios at the end of the experiment.. In the low-potassium dextran group, 2 animals died during reperfusion. After reperfusion, pulmonary vascular resistance (P = .01) and pulmonary artery pressure remained lower in the glutathione/low-potassium dextran group, which was associated with a higher cardiac output (P = .05) in this group. Also, the oxygenation index at the end of the observation period was higher in the glutathione/low-potassium dextran group compared with the low-potassium dextran group (430 +/- 130 vs 338 +/- 184, respectively; P < .05). The graft water content representing postreperfusion lung edema was not different between the 2 study groups. Alteration of surfactant was less in the glutathione/low-potassium dextran group with a significantly decreased small to large aggregate ratio (P = .03) versus low-potassium dextran group. Myeloperoxidase activity was twice as high in the low-potassium dextran group when compared with the glutathione/low-potassium dextran group (glutathione/low-potassium dextran: 134 +/- 110 mU/g vs low-potassium dextran: 274 +/- 168 mU/g, P = .07).. The addition of glutathione to low-potassium dextran preservation solution reveals beneficial effects on vascular function and surfactant composition in transplanted lungs. Therefore, glutathione ameliorates ischemia-reperfusion injury in a preclinical model of lung transplantation. Future studies are needed to evaluate this promising modification in clinical lung transplantation.

Topics: Animals; Blood Pressure; Body Water; Cardiac Output; Dextrans; Female; Glutathione; Lung; Lung Transplantation; Organ Preservation; Organ Preservation Solutions; Peroxidase; Potassium; Pulmonary Artery; Pulmonary Circulation; Pulmonary Surfactants; Reperfusion Injury; Swine; Vascular Resistance

Neutrophil activation followed by free radical production is a feature that is common to the various forms of gastric injury. However, the roles of cyclooxygenase (COX)-1 and -2 in neutrophil activation have yet to be clarified in the gastric mucosa. We examined the roles of both COX-1 and COX-2 in neutrophil activation and free radical production in ischemia-reperfusion (IR) injury in the gastric mucosa of mice.. Ischemia was induced by clamping the celiac artery for 30 min, then removing the clamp for 90 min. SC-560, a selective COX-1 inhibitor; NS-398, a selective COX-2 inhibitor; or rebamipide, a mucoprotective agent, was administered to mice 60 min before ischemia. Gastric damage was evaluated histologically and by measuring myeloperoxidase (MPO) activity. Expressions of COX protein and intercellular adhesion molecule (ICAM)-1 were evaluated by Western blot analysis and ELISA, respectively. Effects of these drugs on thiobarbituric acid reactive substances (TBARS) and gastric blood flow were also evaluated.. COX-2 expression was induced in gastric mucosa 60 min after reperfusion, whereas COX-1 expression remained unaltered. Localization of COX-1 and ICAM-1 in IR-injured mucosa was observed mainly in endothelial cells, while COX-2 expression was detected in mesenchymal cells such as mononuclear cells, spindle-like cells and endothelial cells. SC-560 significantly decreased gastric blood flow at the reperfusion point and reduced gastric mucosal injury in IR mice. Furthermore, SC-560 pretreatment significantly reduced MPO activity, TBARS levels and ICAM-1 expression. In contrast, NS-398 significantly increased ICAM-1 expression, MPO activity and TBARS levels, and aggravated gastric damage in IR mice. Rebamipide pretreatment reduced both COX-2 expression and IR injury.. In IR mice, COX-2 protects the gastric mucosa by down-regulating ICAM-1 expression, whereas COX-1 is involved in up-regulating reperfusion flow, thereby aggravating the mucosa.

Topics: Alanine; Animals; Blotting, Western; Celiac Artery; Cyclooxygenase 1; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Cyclooxygenase Inhibitors; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Female; Gastric Mucosa; Intercellular Adhesion Molecule-1; Laser-Doppler Flowmetry; Ligation; Membrane Proteins; Mice; Mice, Inbred ICR; Nitrobenzenes; Peroxidase; Prostaglandin-Endoperoxide Synthases; Pyrazoles; Quinolones; Regional Blood Flow; Reperfusion Injury; Sulfonamides; Thiobarbituric Acid Reactive Substances

Oxygen free radicals are important components involved in pathophysiological tissue alteration observed during ischemia/reperfusion (I/R). This study was designed to determine the possible protective effect of aqueous garlic extract (AGE) on renal I/R injury. Wistar albino rats were unilaterally nephrectomized and subjected to 45 minutes of renal pedicle occlusion followed by 6 hours of reperfusion. AGE (1 mL/kg, i.p., corresponding to 500 mg/kg) or vehicle was administered twice: 15 minutes prior to ischemia and immediately before the reperfusion period. At the end of the reperfusion period, rats were killed by decapitation. Kidney samples were taken for histological examination or determination of levels of free radicals; renal malondialdehyde (MDA), an end product of lipid peroxidation; glutathione (GSH), a key antioxidant; and myeloperoxidase (MPO) activity, an index of tissue neutrophil infiltration. Renal tissue collagen content, as a fibrosis marker, was also determined. Creatinine and urea concentrations in blood were measured for the evaluation of renal function. The results revealed that I/R-induced nephrotoxicity, as evidenced by increases in blood urea and creatinine levels, was reversed by AGE treatment. The levels of free radicals, as assessed by the nitro blue tetrazolium test, were increased. Moreover, the decrease in GSH levels and the increases in MDA levels and MPO activity induced by I/R indicated that renal injury involves free radical formation. Treatment of rats with AGE (1 mL/kg) restored the reduced GSH levels, while it decreased free levels of radicals and MDA as well as MPO activity. Collagen contents of the kidney tissues increased by I/R were reversed back to the control levels with AGE. Since AGE administration reversed these oxidant responses and improved renal function and damage at the microscopic level, it seems likely that AGE protects kidney tissue against I/R-induced oxidative damage.

Topics: Animals; Collagen; Free Radicals; Garlic; Glutathione; Kidney; Kidney Glomerulus; Male; Malondialdehyde; Peroxidase; Plant Extracts; Rats; Rats, Wistar; Reperfusion Injury; Water

The functions of polymorphonuclear leukocytes (PMNs), which play a critical role in organ damage, are primed in patients with essential hypertension and spontaneously hypertensive rats (SHR). Hepatic ischemia-reperfusion (I/R) injury is shown to be caused and aggravated by the PMNs. We examined whether the hepatic I/R injury was exaggerated in SHR.. The portal vein and artery were partially occluded for 60 min. Blood samples were obtained to determine the degree of liver damage during 48 h after reperfusion.. The increase in serum transaminase concentration and hepatic myeloperoxidase content, which reflects the number of PMNs in liver tissue, in SHR were significantly greater than those of their control rats, Wistar-Kyoto rat (WKY). However, the elevations in hepatic transaminases induced by I/R did not differ between other hypertensive animal models (N-nitro-L-arginine methyl ester [L-NAME]-treated and deoxycorticosterone acetate [DOCA]/salt-treated rats) and their controls.. These results suggest that the elevated PMNs, but not high blood pressure per se, contributes to the exaggerated hepatic I/R injury in SHR.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Biomarkers; Blood Pressure; Desoxycorticosterone; Enzyme Inhibitors; Heart Rate; Hypertension; Liver; Liver Diseases; Male; Neutrophils; NG-Nitroarginine Methyl Ester; Nitric Oxide Synthase; Peroxidase; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Rats, Wistar; Reperfusion Injury; Tumor Necrosis Factor-alpha

This study analyzes the role of T lymphocytes and neutrophils (PMN) in intestinal ischemia and reperfusion injury (IRI) using either P-selectin blockade or elimination.. Using a model of severe mouse warm intestinal IRI, the following groups were performed: group 1: wild type C57BL6 no treatment; group 2: wild type treated with r-PSGL1-Ig; group 3: C57BL6 genetically deficient in P-selectin. Survival was assessed at day 7; intestine was assayed for histopathology, apoptosis, myeloperoxidase (MPO), inflammatory cytokines, hemoxygenase-1 (HO-1), and CD3 lymphocytes. Standard statistical comparison was undertaken.. The survival was significantly (P < 0.01) improved in the treatment groups: group 1, 50%; group 2, 90%; group 3, 100%. Graded histopathology and crypt apoptosis were improved in groups 2 and 3. MPO and CD3 positive cells were significantly reduced in groups 2 and 3. A significant reduction in inflammatory/Th1-type cytokines was seen in groups 2 and 3 as compared to group 1. Conversely, a significant increase in Th2-type cytokines and HO-1 production was seen selectively in groups 2 and 3.. This study demonstrates the importance of P-selectin signaling in warm, murine intestinal IRI in that either the blockade of or the genetic deficiency in P-selectin confers a survival advantage and reduction in tissue injury/inflammation. The mechanism involves a reduction of PMN and CD3 T cell infiltration and an alteration in the cytokine microenvironment in favor of a Th2 profile. These data implicate T lymphocyte as an important regulatory cell in this inflammatory process.

Topics: Animals; Apoptosis; CD3 Complex; Cell Movement; Cytokines; Heme Oxygenase-1; Intestinal Mucosa; Intestines; Mice; Mice, Inbred C57BL; P-Selectin; Peroxidase; Protein Transport; Reperfusion Injury; Signal Transduction; Survival Rate; Th1 Cells; Th2 Cells; Treatment Outcome; Warm Ischemia

The current study explored the concept that adult and pediatric populations differ in their response to major injury. Male C57BL/6 mice of a "young adult" (8-12 weeks) or "mature adult" (12-13 months) age were subjected to partial hepatic ischemia and reperfusion. Mature adult mice displayed significantly more liver injury than young adult mice as assessed histologically and by serum levels of alanine aminotransferase. Interestingly, there was far less neutrophil accumulation in the livers of mature adult mice. However, liver-recruited neutrophils from mature adult mice had a higher activation state than those from young adult mice. Activation of the inflammatory transcription factor, NF-kappaB, was suppressed in whole livers from mature adult mice. In isolated liver cells, Kupffer cells showed no difference in NF-kappaB activation, but hepatocytes from mature adult mice had delayed NF-kappaB activation in response to TNF. Furthermore, isolated hepatocytes from young adult mice produced abundant amounts of the chemokine, macrophage inflammatory protein-2, whereas hepatocytes from mature adult mice produced little, if any macrophage inflammatory protein-2. Mature adult mice had much lower hepatic expression of the cytoprotective protein, heat shock protein 70, than did young adult mice. In contrast, serum heat shock protein 70 levels, which has been linked to subsequent tissue injury, were higher in mature adult mice than in young adult mice. These data suggest that there are multiple alterations at the cellular and molecular levels that contribute to enhanced postischemic liver injury in mature adult mice.

Topics: Age Factors; Aging; Animals; Blotting, Western; Chemokine CXCL2; Cytokines; Hepatocytes; HSP70 Heat-Shock Proteins; Inflammation; Kupffer Cells; Lipopolysaccharides; Liver; Male; Mice; Mice, Inbred C57BL; Monokines; Neutrophils; NF-kappa B; Peroxidase; Reperfusion Injury; Time Factors; Transcription, Genetic

Cyclooxygenase (COX)-2 has been identified as an important mediator elaborated during ischemia/reperfusion, with pro- and anti-inflammatory properties having been reported. As the role of COX-2 in the small intestine remains unclear, we hypothesized that COX-2 expression would mediate mesenteric ischemia/reperfusion-induced gut injury, inflammation, and impaired transit and that these deleterious effects could be reversed by the selective COX-2 inhibitor, N-[2-(cyclohexyloxy)-4-nitrophenyl] methanesulphanamide (NS-398). Additionally, we sought to determine the role of peroxisome proliferator-activated receptor gamma (PPARgamma) in mediating protection by NS-398 in this model. Rats underwent sham surgery or were pretreated with NS-398 (3, 10, or 30 mg/kg) intraperitoneally 1 h before 60 min of superior mesenteric artery occlusion and 30 min to 6 h of reperfusion. In some experiments, NS-398 (30 mg/kg) was administered postischemia. Ileum was harvested for COX-2 mRNA and protein, PGE2, myeloperoxidase (inflammation), histology (injury), intestinal transit and PPARgamma protein expression, and DNA-binding activity. COX-2 expression and PGE2 production increased after mesenteric ischemia/reperfusion and were associated with gut inflammation, injury, and impaired transit. Inhibition of COX-2 by NS-398 (30 mg/kg, but not 3 or 10 mg/kg) not only reversed the deleterious effects of COX-2, but additionally induced expression and nuclear translocation of PPARgamma. NS-398 given postischemia was equally protective. In conclusion, COX-2 may function as a proinflammatory mediator in a rodent model of mesenteric ischemia/reperfusion. Reversal of gut inflammation, injury, and impaired transit by high-dose NS-398 is associated with PPAR activation, suggesting a potential role for PPAR-gamma in shock-induced gut protection.

Topics: Active Transport, Cell Nucleus; Animals; Cell Nucleus; Cyclooxygenase 1; Cyclooxygenase 2; Cyclooxygenase Inhibitors; Cytoplasm; Cytosol; Dinoprostone; DNA; DNA Primers; Dose-Response Relationship, Drug; Gastrointestinal Tract; Inflammation; Intestine, Small; Ischemia; Male; Mesentery; Nitrobenzenes; Peroxidase; PPAR gamma; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sulfonamides; Time Factors

The aim of the present study was to explore whether heme oxygenase-1 (HO-1) is involved in the hyperthermia-provided protection of the small intestine from ischemia/reperfusion injury in rats.. Intestinal damage was induced in male Sprague-Dawley rats by clamping both the superior mesenteric artery and the celiac trunk for 30 min, followed by reperfusion. Whole-body hyperthermia was induced in anesthetized rats by placement in a temperature-controlled water bath. Whole-body hyperthermia to a core temperature of 42-43 degrees C for 15 min was followed by passive cooling. We started the hyperthermic treatment 6 h before the vascular clamping. The severity of the mucosal injury was evaluated by several biochemical markers and histological findings. Hyperthermia-induced heat-shock proteins were detected by Western blotting. We also investigated the effect of zinc protoporphyrin IX (an HO-1 inhibitor) on the protective effect of hyperthermia.. The rats, which were killed after ischemia/reperfusion, had severe intestinal inflammation. Hyperthermia significantly induced the production of Hsp70 and HO-1 in intestinal mucosa and significantly reduced ischemia/reperfusion-induced mucosal injury. The combination of zinc protoporphyrin IX with hyperthermia extinguished the protective effects of hyperthermia on ischemia/reperfusion injury.. Hyperthermia protects against ischemia/reperfusion injury in rat small intestine through the expression of heat-shock proteins, especially HO-1.

Topics: Animals; Chemokines, CXC; Enzyme Induction; Heme Oxygenase (Decyclizing); HSP70 Heat-Shock Proteins; Hyperthermia, Induced; I-kappa B Kinase; Intercellular Signaling Peptides and Proteins; Intestinal Mucosa; Intestine, Small; Male; Peroxidase; Protoporphyrins; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Thiobarbituric Acid Reactive Substances

Lung ischemia-reperfusion injury (LIRI) is associated with an increased incidence of both primary graft failure and obliterative bronchiolitis. The immunosuppressant mycophenolate mofetil (MMF) has recently been shown to attenuate inflammatory injury in acute ischemia-reperfusion models via a mechanism that is presently unclear. These experiments studied the effects of MMF in a warm, in situ LIRI model, focusing on transcriptional regulation of pro-inflammatory mediators.. Left lungs of rats were rendered ischemic for 90 minutes and reperfused for up to 4 hours. Treated animals received 10 mg/kg of intravenous MMF at 2 hours before ischemia. Left lung injury was quantitated by myeloperoxidase (MPO) content, permeability indices and bronchoalveolar lavage (BAL) inflammatory cell counts. Lungs were analyzed by electrophoretic mobility shift assay (EMSA) for transcription factor transactivation and by enzyme-linked immunoassay for BAL chemokine protein content.. MMF significantly reduced lung vascular permeability indices, MPO content and alveolar leukocyte counts at 4 hours of reperfusion. There was significant attenuation of activator protein 1 (AP-1) and early growth response 1 (EGR-1) transactivation, whereas nuclear factor-kappaB (NF-kappaB) was unaffected. Reductions in bronchoalveolar lavage monocyte chemoattractant protein 1 (MCP-1) and cytokine-induced neutrophil chemoattractant (CINC) protein content were found at 4 hours of reperfusion.. MMF limits lung ischemia-reperfusion-induced increases in vascular permeability and inflammatory cell sequestration in lung parenchyma and alveolar spaces. The protection is mediated at the transcriptional level via an attenuation of early EGR-1 and AP-1 transactivation, which was found to be associated with reduced late MCP-1 and CINC protein secretion. The use of MMF in concert with an agent that affects NF-kappaB activation may provide even further protection against lung reperfusion injury as multiple inflammatory pathways are inhibited.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Bronchiolitis Obliterans; Bronchoalveolar Lavage Fluid; Chemokines; Electrophoretic Mobility Shift Assay; Enzyme-Linked Immunosorbent Assay; Graft Rejection; Inflammation; Lung; Lung Transplantation; Male; Mycophenolic Acid; Permeability; Peroxidase; Postoperative Complications; Rats; Rats, Long-Evans; Reperfusion Injury; Transcription Factors; Transcription, Genetic

To observe the protective effect of ischemic postconditioning on ischemic reperfusion injury of rat liver graft and to investigate the possible mechanism.. Male Sprague Dawley rats were used as donors and recipients of orthotopic liver transplantation, and the period of cold preservation and anhepatic phase were 100 min and 18 min, respectively. Sixty rats were randomly divided into three groups, twelve rats in control group, twenty-four rats in ischemic reperfusion injury group and ischemic postconditioning group respectively. Control group is sham operation group, only the ligaments around liver were cut off; donor livers in ischemic reperfusion injury group were infused through portal vein with heparinized saline before harvested; ischemic postconditioning group: at very onset of reperfusion after donor liver was implanted, several brief reperfusion-ischemia were given before persistent reperfusion of portal vein. Half recipients of ischemic reperfusion injury group and ischemic postconditioning group were taken blood samples and hepatic tissue samples after 2 hours of reperfusion of liver graft. Rest recipients were taken samples of hepatic tissue after 6 hours of reperfusion. Recipients of control group were taken blood and hepatic tissue samples at corresponding time after abdomen was sutured.. Compared with ischemic reperfusion injury group, liver functional parameters, cytokines and peroxidized products contents were lower in ischemic postconditioning group (P < 0.05); meanwhile, the antioxidases contents of hepatic tissue were higher in ischemic postconditioning group than those in ischemic reperfusion injury group (P < 0.05).. Ischemic postconditioning could relieve the ischemic reperfusion injury of rat liver graft. Through improving antioxidation capability and cutting down cytokines contents, ischemic postconditioning could apply its protective effect.

Topics: Animals; Glutathione Peroxidase; Leukocyte Elastase; Liver; Liver Transplantation; Male; Malondialdehyde; Peroxidase; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Superoxide Dismutase; Tumor Necrosis Factor-alpha

To evaluate the protective effect of NF-kappaB decoy oligodeoxynucleotides (ODNs) on ischemia/reperfusion (I/R) injury in rat liver graft.. Orthotopic syngeneic rat liver transplantation was performed with 3 h of cold preservation of liver graft in University of Wisconsin solution containing phosphorothioated double-stranded NF-kappaB decoy ODNs or scrambled ODNs. NF-kappaB decoy ODNs or scrambled ODNs were injected intravenously into donor and recipient rats 6 and 1 h before operation, respectively. Recipients were killed 0 to 16 h after liver graft reperfusion. NF-kappaB activity in the liver graft was analyzed by electrophoretic mobility shift assay (EMSA). Hepatic mRNA expression of TNF-alpha, IFN-gamma and intercellular adhesion molecule-1 (ICAM-1) were determined by semiquantitative RT-PCR. Serum levels of TNF-alpha and IFN-gamma were measured by enzyme-linked immunosorbent assays (ELISA). Serum level of alanine transaminase (ALT) was measured using a diagnostic kit. Liver graft myeloperoxidase (MPO) content was assessed.. NF-kappaB activation in liver graft was induced in a time-dependent manner, and NF-kappaB remained activated for 16 h after graft reperfusion. NF-kappaB activation in liver graft was significant at 2 to 8 h and slightly decreased at 16 h after graft reperfusion. Administration of NF-kappaB decoy ODNs significantly suppressed NF-kappaB activation as well as mRNA expression of TNF-alpha, IFN-gamma and ICAM-1 in the liver graft. The hepatic NF-kappaB DNA binding activity [presented as integral optical density (IOD) value] in the NF-kappaB decoy ODNs treatment group rat was significantly lower than that of the I/R group rat (2.16+/-0.78 vs 36.78+/-6.35 and 3.06+/-0.84 vs 47.62+/- 8.71 for IOD value after 4 and 8 h of reperfusion, respectively, P<0.001). The hepatic mRNA expression level of TNF-alpha, IFN-gamma and ICAM-1 [presented as percent of beta-actin mRNA (%)] in the NF-kappaB decoy ODNs treatment group rat was significantly lower than that of the I/R group rat (8.31+/-3.48 vs 46.37+/-10.65 and 7.46+/- 3.72 vs 74.82+/-12.25 for hepatic TNF-alpha mRNA, 5.58+/-2.16 vs 50.46+/-9.35 and 6.47+/-2.53 vs 69.72+/-13.41 for hepatic IFN-gamma mRNA, 6.79+/-2.83 vs 46.23+/-8.74 and 5.28+/-2.46 vs 67.44+/-10.12 for hepatic ICAM-1 mRNA expression after 4 and 8 h of reperfusion, respectively, P<0.001). Administration of NF-kappaB decoy ODNs almost completely abolished the increase of serum level of TNF-alpha and IFN-gamma induced by hepatic ischemia/reperfusion, the serum level (pg/mL) of TNF-alpha and IFN-gamma in the NF-kappaB decoy ODNs treatment group rat was significantly lower than that of the I/R group rat (42.7+/-13.6 vs 176.7+/-15.8 and 48.4+/-15.1 vs 216.8+/-17.6 for TNF-alpha level, 31.5+/-12.1 vs 102.1+/-14.5 and 40.2+/-13.5 vs 118.6+/-16.7 for IFN-gamma level after 4 and 8 h of reperfusion, respectively, P<0.001). Liver graft neutrophil recruitment indicated by MPO content and hepatocellular injury indicated by serum ALT level were significantly reduced by NF-kappaB decoy ODNs, the hepatic MPO content (A655) and serum ALT level (IU/L) in the NF-kappaB decoy ODNs treatment group rat was significantly lower than that of the I/R group rat (0.17+/-0.07 vs 1.12+/-0.25 and 0.46+/-0.17 vs 1.46+/-0.32 for hepatic MPO content, 71.7+/-33.2 vs 286.1+/-49.6 and 84.3+/-39.7 vs 467.8+/-62.3 for ALT level after 4 and 8 h of reperfusion, respectively, P<0.001).. The data suggest that NF-kappaB decoy ODNs protects against I/R injury in liver graft by suppressing NF-kappaB activation and subsequent expression of proinflammatory mediators.

Topics: Animals; Intercellular Adhesion Molecule-1; Interferon-gamma; Liver; Liver Transplantation; Male; Neutrophils; NF-kappa B; Oligonucleotides; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

To evaluate the effects of dipfluzine on the expressions of E-selectin, P-selectin, and ICAM-1 and the infiltration of polymorphonuclear leukocytes in brain ischemia-reperfusion rats.. The model of focal cerebral ischemia was established with the Zea-Longa occluding suture. Dipfluzine (0.25, 0.5 and 1 mg x kg(-1)), flunarizine 0.5 mg x kg(-1) and solvent were injected separately into lingual vein at 30 min after ischemia. The occluding suture was slowly taken away to cause reperfusion at 1 h after ischemia. Rats were decapitated under anesthesia at 24 h after ischemia-reperfusion and brains were immediately removed to do the following procedures. Effects of dipfluzine on morphology of the brain tissue were observed through hematoxylin-eosin (HE) staining. By immunohistochemistry and flow cytometry technique and biochemical method, effects of dipfluzine on P-selectin, E-selectin, ICAM-1 and myeloperoxidase (MPO) were observed.. Dipfluzine could relieve pathological damages in the brain tissue after ischemia-reperfusion, and reduce the expressions of E-selectin, P-selectin and ICAM-1 and activities of MPO in dose-dependent manner.. Dipfluzine depresses the expressions of P-selectin, E-selectin, and ICAM-1, which are correlated with their effects on the activities of MPO, suggesting that dipfluzine has anti-inflammation effect in certain extent and could protect brain tissue from ischemia-reperfusion injury.

Topics: Animals; Brain Ischemia; Cerebral Cortex; Cinnarizine; Dose-Response Relationship, Drug; E-Selectin; Infarction, Middle Cerebral Artery; Intercellular Adhesion Molecule-1; Male; Neuroprotective Agents; P-Selectin; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Peroxisome proliferator-activated receptor-alpha (PPARalpha) is a transcription factor that in some in vitro systems has been linked with downregulation of proinflammatory mediators, thus implicating a potential role for PPARalpha in the regulation of inflammatory processes. Hepatic ischemia-reperfusion injury is characterized by an intense acute inflammatory response that is dependent on a number of proinflammatory mediators. PPARalpha is abundantly expressed in hepatic parenchymal cells but not in Kupffer cells. This study examined whether PPARalpha is involved in regulation of the hepatic inflammatory response to ischemia-reperfusion. Mice nullizygous for PPARalpha had significantly greater liver injury than did their wild-type counterparts. Consistent with these findings, C57BL/6 mice treated with the PPARalpha agonist, WY-14643, had significantly less liver injury than mice receiving vehicle. PPARalpha-knockout mice also had greatly augmented liver neutrophil accumulation and modest increases in activation of the transcription factors NF-kappaB and activator protein-1. However, these effects were not associated with increased expression of proinflammatory cytokines or chemokines. In addition, PPARalpha-knockout mice expressed far less inducible nitric oxide synthase in liver than did wild-type mice after ischemia-reperfusion. Finally, treatment of cultured murine hepatocytes with WY-14643, a specific agonist of PPARalpha, protected cells against oxidant-induced injury. The data suggest that PPARalpha is an important regulator of the hepatic inflammatory response to ischemia-reperfusion in a manner that is independent of proinflammatory cytokines.

Topics: Animals; Antioxidants; Blotting, Western; Cell Survival; Cells, Cultured; Chemokines; Cytokines; Electrophoretic Mobility Shift Assay; Hepatocytes; Hydrogen Peroxide; Liver; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophils; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Oxidants; Peroxidase; Pyrimidines; Receptors, Cytoplasmic and Nuclear; Reperfusion Injury; Transcription Factors

In this study we evaluated the effect of calpain inhibitor I on splanchnic artery occlusion (SAO) shock-mediated injury. SAO shock was induced in rats by clamping both the superior mesenteric artery and the celiac trunk for 45 min. After 1 h of reperfusion, SAO-shocked rats developed a significant fall in mean arterial blood pressure. Western blot analysis of ileum revealed a marked decrease in of IkappaB-alpha expression, and immunohistochemical examination of necrotic ileum demonstrated a marked increase in the immunoreactivity to P-selectin, intracellular adhesion molecule (ICAM-1), nitrotyrosine formation, and nuclear enzyme poly[adenosine diphosphate (ADP)-ribose] synthase (PARS) activation. An increase in myeloperoxidase activity (143 +/- 22 4.5 U/100 mg wet tissue vs. 4.5 +/- 2.5 U/100 mg wet tissue of sham-operated rats) and in malondialdehyde levels (13.12 +/- 1.2 micromol/100 mg wet tissue vs. 3.9 +/- 1.1 micromol/100 mg wet tissue of sham-operated rats) was also observed in rats subjected to ischemia-reperfusion injury. Calpain inhibitor I, given intraperitoneally 30 min before ischemia at a dose of 15 mg/kg, significantly improved mean arterial blood pressure, markedly reduced IkappaB-alpha degradation and the intensity of P-selectin and ICAM-1 in the reperfused ileum. Calpain inhibitor I also significantly prevented neutrophil infiltration (32.95 +/- 9.82 U/100 mg wet tissue), reduced malondialdehyde levels (6.76 +/- 0.98 micromol/100 mg wet tissue) and markedly improved the histological status of the reperfused tissue. In conclusion, this study demonstrates that calpain inhibitor I exerts multiple protective effects in splanchnic artery occlusion-reperfusion shock and suggests that calpain inhibitor I may be a candidate for consideration as a therapeutic intervention for ischemia-reperfusion injury.

Topics: Animals; Blood Pressure; Blotting, Western; Cysteine Proteinase Inhibitors; Glycoproteins; I-kappa B Proteins; Ileum; Immunohistochemistry; Intercellular Adhesion Molecule-1; Lipid Peroxidation; Male; Malondialdehyde; Neutrophils; NF-KappaB Inhibitor alpha; P-Selectin; Peroxidase; Poly(ADP-ribose) Polymerases; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Shock; Splanchnic Circulation; Time Factors; Tyrosine

Increased microvascular permeability and extravasation of inflammatory cells are key events of lung ischemia-reperfusion (IR) injury. The purpose of this study was to investigate the role of matrix metalloproteinases (MMP) in IR-induced alveolar capillary membrane disruption after experimental lung transplantation. We used a rat model of lung orthotopic transplantation (n = 86) with a prolonged cold ischemic phase. MMP2 and MMP9 were elevated 4 h after the onset of ischemia and further increased during reperfusion. Compared to sham values, the alveolar-capillary membrane permeability increased by 105% and 82.6% after 4 h of ischemia and 2 h or 24 h of reperfusion, respectively. A 4- and 5-fold increase of the infiltration of ischemic tissue by neutrophils was also observed after 2 h and 24 h of reperfusion. The PO2/FIO2 ratio dropped significantly from 244 to 76.6 after 2 h of reperfusion and from 296.4 to 127.6 after 24 h of reperfusion. A nonselective inhibitor of MMP, administered to the rats and added to the preservation solution, reduced significantly the alveolar-capillary leakage, the transmigration of neutrophils and improved gas exchanges in animals submitted to 4 h of ischemia combined with 2 h or 24 h of reperfusion. We conclude that inhibition of MMP attenuates IR injury after experimental lung transplantation.

Topics: Animals; Capillaries; Coloring Agents; Enzyme Inhibitors; Evans Blue; Hypoxia; Ischemia; Lung; Lung Transplantation; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Matrix Metalloproteinase Inhibitors; Microscopy, Fluorescence; Neutrophils; Peroxidase; Placebos; Rats; Rats, Inbred F344; Reperfusion Injury; Time Factors

The aim of this study was to determine the acute effects of antioxidant caffeic acid phenethyl ester (CAPE) and alpha-tocopherol (vitamin E) on nitric oxide (NO) production, neutrophil infiltration, and antioxidant enzyme activities on an in vivo model of renal ischemia-reperfusion injury.. Rats were divided into five equal groups each consisting six rats: sham operation, ischemia, ischemia-reperfusion (I/R), I/R plus CAPE, and I/R plus vitamin E groups. CAPE or vitamin E was administered intraperitoneally before reperfusion. After experimental procedure, rats were sacrificed and both ipsilateral and contralateral kidneys were removed and prepared for NO concentrations, myeloperoxidase (MPO), catalase (CAT) and superoxide dismutase (SOD) activities.. Acute administration of vitamin E decreased NO concentrations in both ipsilateral and contralateral renal tissues compared to I/R group. SOD activity was increased in I/R and I/R + CAPE groups compared to sham operation group. The most prominent results were encountered in MPO activities, which did not change in contralateral kidneys in both ischemia and I/R groups. There was a significant decrease in ipsilateral MPO activity in ischemia group and a significant increase in I/R group compared to sham operation group. Pretreatment with intraperitoneal CAPE significantly diminished the tissue MPO activity indicating the prevention of the neutrophil sequestration into the kidney.. There is a role for CAPE in attenuation in renal damage after I/R injury of the kidney, in part at least by inhibition of neutrophil sequestration.

Topics: alpha-Tocopherol; Animals; Antioxidants; Caffeic Acids; Catalase; Kidney; Nitric Oxide; Peroxidase; Phenylethyl Alcohol; Rats; Rats, Wistar; Reperfusion Injury; Superoxide Dismutase

Antithrombin (AT) reveals its antiinflammatory activity by promoting endothelial release of prostacyclin (PGI(2)) in vivo. Since neuroinflammation is critically involved in the development of ischemia/reperfusion (I/R)-induced spinal cord injury (SCI), it is possible that AT reduces the I/R-induced SCI by attenuating the inflammatory responses. We examined this possibility using rat model of I/R-induced SCI in the present study. AT significantly reduced the mortality and motor disturbances by inhibiting reduction of the number of motor neurons in animals subjected to SCI. Microinfarctions of the spinal cord seen after reperfusion were markedly reduced by AT. AT significantly enhanced the I/R-induced increases in spinal cord tissue levels of 6-keto-PGFIalpha, a stable metabolite of PGI2. AT significantly inhibited the I/R-induced increases in spinal cord tissue levels of TNF-alpha, rat interleukin-8 and myeloperoxidase. In contrast,Trp(49) -modified AT did not show any protective effects. Pretreatment with indomethacin significantly reversed the protective effects of AT. An inactive derivative of factor Xa, which selectively inhibits thrombin generation, has been shown to fail to reduce SCI. Taken together, these observations strongly suggested that AT might reduce I/R-induced SCI mainly by the antiinflammatory effect through promotion of endothelial production of PGI(2). These findings also suggested that AT might be a potential neuroprotective agent.

Topics: 6-Ketoprostaglandin F1 alpha; Animals; Antithrombins; Coloring Agents; Disease Models, Animal; Epoprostenol; Factor Xa; Humans; Inflammation; Interleukin-8; Ischemia; Male; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Spinal Cord; Spinal Cord Injuries; Tetrazolium Salts; Time Factors; Tryptophan; Tumor Necrosis Factor-alpha

The neuroprotective effect of hypothermia has long been recognized. Use of hypothermia for stroke therapy, which is currently being induced by whole body surface cooling, has been largely limited because of management problems and severe side effects (i.e., pneumonia). Our recent studies have demonstrated the significant therapeutic value of local brain cooling in the ischemic territory prior to reperfusion in stroke. The goal of this study was to determine if cerebral local cooling infusion could reduce stroke-mediated brain injury by inhibiting inflammatory responses. A hollow filament was used to block the middle cerebral artery (MCA) for 3 hours, and then to locally infuse the ischemic territory with 6 ml cold saline (20 degrees C) for 10 min prior to 48-h reperfusion. This cold saline infusion significantly ( P<0.01) reduced temperature of the MCA supplied territory (in cerebral cortex from 37.2+/-0.1 degrees C to 33.4+/-0.4 degrees C, in striatum from 37.5+/-0.2 degrees C to 33.9+/-0.4 degrees C), with the hypothermia remaining for at least 45 min after reperfusion. Consequently, significant ( P<0.01) reductions in endothelial expression of intracellular adhesion molecule-1 (ICAM-1), the key step for inflammatory progress, as well as leukocyte infiltration, were evident in both cortex and striatum after reperfusion. As a control, ischemic rats received the same amount of cold saline systemically through a femoral artery. A mild hypothermia was induced in the cerebral cortex (35.3+/-0.2 degrees C) but not in the striatum (36.8+/-0.2 degrees C). The reduced cortical temperature returned to normal within 5 min. Brain temperature in ischemic rats perfused locally with saline at 37 degrees C remained normal. Intensive expression of ICAM-1 and accumulation of leukocytes was observed in ischemic control groups without brain cooling infusion. In conclusion, brain hypothermia induced by local pre-reperfusion infusion ameliorated brain inflammation from stroke.

Topics: Analysis of Variance; Animals; Body Temperature; Cell Count; Cerebral Cortex; Corpus Striatum; Hypothermia, Induced; Immunohistochemistry; Infarction, Middle Cerebral Artery; Inflammation; Intercellular Adhesion Molecule-1; Male; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sodium Chloride

Ischemic preconditioning (I/P) and methylprednisolone (MP) have been suggested to protect against ischemia-reperfusion (IR) injury, which results in an increased tolerance against organ hypoxia.. Before 45 minutes of hepatic ischemia, male Wistar rats were pretreated with either I/P (5/30 minutes) or MP (30 mg/kg BW). The degree of IR injury and the postischemic inflammatory (leukocyte infiltration, myeloperoxidase, intercellular adhesion molecule-1) and apoptotic (TUNEL, caspase 3, cytochrome C) activity was measured in both groups and compared with non-pretreated (ischemic) animals.. Histology and enzyme release revealed that I/P and MP treatment provided significant protection as compared with ischemic controls. TUNEL-positive cells, as well as caspase 3 and cytochrome C expression, were clearly reduced in hepatic tissue of MP-treated animals and partially reduced in I/P-treated animals when compared with ischemic animals. The inflammatory response was considerably reduced in MP- and I/P-treated animals, especially in the early period after ischemia. NF-kappaB/Rel-binding activity was increased after I/P and decreased in MP-treated animals, whereas ischemic controls showed a constant binding activity.. MP (probably by downregulation of NF-kappaB-binding activity) and I/P attenuated the postischemic apoptotic and inflammatory response. Both treatments equally reduced IR-related hepatocellular damage, and, thus, may also be applied equally in surgery involving warm organ hypoxia.

Topics: Animals; Anti-Inflammatory Agents; Apoptosis; Caspase 3; Caspases; Cytochromes c; Gene Expression Regulation; Hot Temperature; In Situ Nick-End Labeling; Intercellular Adhesion Molecule-1; Ischemic Preconditioning; Leukocytes; Liver; Male; Methylprednisolone; NF-kappa B; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Ischemia/reperfusion injury plays an important role in the pathogenesis of abdominal compartment syndrome, which is characterized by increased intra-abdominal pressure. The aim of this study was to investigate whether octreotide, a synthetic somatostatin analogue, improves the reperfusion injury after decompression of acute abdominal hypertension. This study was carried out in Wistar albino rats. With the rats under anesthesia, an arterial catheter was inserted intraperioneally and with the use of an aneroid manometer connected to the catheter, intra-abdominal pressure was kept at 20 mm Hg (ischemia group) for 1 hour. In the ischemia/reperfusion group, pressure applied for 1 hour was decompressed and a 1-hour reperfusion period was allowed. In another ischemia/reperfusion group, octreotide was administered (50 microg/kg intraperitoneally) immediately before the decompression of intra-abdominal pressure. At the end of the experiment, liver and intestinal tissues were taken and malondialdehyde (an index of lipid peroxidation) and glutathione (a key to antioxidant) levels and myeloperoxidase (an index of tissue neutrophil infiltration) activity were estimated. The results demonstrated that tissue levels of malondialdehyde and myeloperoxidase activity were elevated, whereas glutathione levels were reduced in both the ischemia and ischemia/reperfusion groups. Octreotide treatment reversed these oxidant responses. In conclusion, increased intra-abdominal pressure causes oxidative organ damage and octreotide, by controlling the reperfusion of abdominal organs and inhibiting neutrophil infiltration, could improve the reperfusion-induced oxidative damage. Therefore its therapeutic role as a "reperfusion injury-limiting" agent must be further elucidated in intra-aortic pressure-induced abdominal organ injury.

Topics: Abdomen; Animals; Compartment Syndromes; Female; Gastrointestinal Agents; Lipid Peroxidation; Male; Neutrophil Infiltration; Octreotide; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

We previously demonstrated that calcineurin inhibitors given intravenously ameliorate experimental lung ischemia-reperfusion injury. This study evaluates whether these effects can be achieved when these agents are delivered endotracheally.. Left lungs of Long Evans rats were rendered ischemic for 90 minutes and reperfused for up to 4 hours. Treated animals received tacrolimus endotracheally at doses of 0.2, 0.1, or 0.025 mg/kg 60 minutes before ischemia. Injury was quantitated in terms of vascular permeability. Additional animals treated at a dose of 0.1 mg/kg were assessed for lung tissue myeloperoxidase content and bronchoalveolar lavage leukocyte content. Bronchoalveolar lavage fluid was assessed for cytokine and chemokine content by enzyme-linked immunosorbent assay. Tissue samples were processed for nuclear factor-kappaB activation, and blood levels of tacrolimus were measured in treated animals.. Left lung vascular permeability was reduced in treated animals in a dose-dependent fashion compared with controls. The protective effects correlated with a 47% (0.50% +/- 0.06% vs 0.27% +/- 0.08%, respectively) reduction in tissue myeloperoxidase content (P <.004) and marked reductions in bronchoalveolar lavage leukocyte accumulation. This protection was also associated with decreased nuclear factor-kappaB activation and diminished expression of proinflammatory mediators. Blood tacrolimus levels in treated animals at 4 hours of reperfusion were undetectable.. Tacrolimus administered endotracheally is protective against lung ischemia-reperfusion injury in our model. This protection is associated with a decrease in nuclear factor-kappaB activation. This route of tacrolimus administration broadens its potential clinical use and decreases concerns about systemic and renal toxicity. It may be a useful therapy in lung donors to protect against lung ischemia-reperfusion injury.

Topics: Animals; Bronchoalveolar Lavage Fluid; Calcineurin; Capillary Permeability; Cell Count; Chemokines, CXC; Cytokines; Disease Models, Animal; Dose-Response Relationship, Drug; Electrophoretic Mobility Shift Assay; Immunosuppressive Agents; Intercellular Signaling Peptides and Proteins; Lung; Male; Models, Cardiovascular; NF-kappa B; Peroxidase; Rats; Rats, Long-Evans; Reperfusion Injury; Tacrolimus; Treatment Outcome

CD39 (ecto-nucleoside triphosphate diphosphohydrolase-1; E-NTPDase-1), is highly expressed on quiescent vascular endothelial cells and efficiently hydrolyzes extracellular ATP and ADP to AMP and ultimately adenosine. This action blocks extracellular nucleotide-dependent platelet aggregation and abrogates endothelial cell activation. However, CD39 enzymatic activity is rapidly lost following exposure to oxidant stress. Modulation of extracellular nucleotide levels may therefore play an important role in the pathogenesis of vascular injury. Acute ischemic injury of the bowel is a serious medical condition characterized by high mortality rates with limited therapeutic options. Here we evaluate the effects of cd39-deletion in mutant mice and the use of supplemental NTPDase or adenosine in influencing the outcomes of intestinal ischemia-reperfusion. Wild-type, cd39-null, or hemizygous cd39-deficient mice were subjected to intestinal ischemia. In selected animals, 0.2 U/g apyrase (soluble NTPDase) was administered prior to re-establishment of blood-flow. In parallel experiments adenosine/amrinone was infused over 60 min during reperfusion periods. Survival rates were determined, serum and tissue samples were taken. Intravital videomicroscopy and studies of vascular permeability were used to study platelet-endothelial cell interactions and determine capillary leakage. In wild-type animals, ischemia reperfusion injury resulted in 60% mortality within 48 hours. In mutant mice null or deficient for cd39, ischemia reperfusion-related death occurred in 80% of animals. Apyrase supplementation protected all wild-type animals from death due to intestinal ischemia but did not fully protect cd39-null and cd39-hemizygote mice. Adenosine/amrinone treatment failed to improve survival figures. In wild type mice, platelet adherence to postcapillary venules was significantly decreased and vascular integrity was well preserved following apyrase administration. In cd39-null mice, ischemia-reperfusion induced marked albumin leakage indicative of heightened vascular permaeability when compared to wild-type animals (p=0.04). Treatment with NTPDase or adenosine supplementation abrogated the increased vascular permeability in ischemic jejunal specimens of both wild-type mice and cd39-null. CD39 activity modulates platelet activation and vascular leak during intestinal ischemia reperfusion injury in vivo. The potential of NTPDases to maintain vascular integrity suggests potential pharm

Topics: Adenosine; Adenosine Diphosphate; Adenosine Triphosphatases; Adenosine Triphosphate; Animals; Antigens, CD; Apyrase; Blood Platelets; Capillaries; Cyclic AMP; Cytokines; Endothelium, Vascular; Gene Deletion; Intestine, Small; Ischemia; Male; Mice; Mice, Inbred C57BL; Microscopy, Video; Oxidative Stress; Permeability; Peroxidase; Platelet Activation; Reperfusion Injury; Time Factors; Vascular Endothelial Growth Factor A

Although chemokines are functionally important in models of ischemia-reperfusion injury, little is known about their role in lung ischemia-reperfusion injury (LIRI). This study examined the role of the beta-chemokines, macrophage inflammatory protein (MIP)-1alpha, monocyte chemoattractant protein (MCP)-1, and regulated upon activation normal T cells expressed and secreted (RANTES) in LIRI.. Left lungs of Long-Evans rats underwent normothermic ischemia for 90 minutes and reperfusion for up to 4 hours. Treated animals received anti-MIP-1alpha, anti-MCP-1, or anti-RANTES antibodies before reperfusion. Changes in lung vascular permeability were measured with iodine 125-labeled bovine serum albumin. Neutrophil accumulation in the lung parenchyma was determined by myeloperoxidase activity, and bronchoalveolar lavage was performed to measure leukocyte cell counts. Western blots, Northern blots, and ribonuclease protection assays assessed beta-chemokine messenger RNA and protein levels.. Animals receiving anti-MIP-1alpha demonstrated reduced vascular permeability compared with controls (p < 0.001). Attenuation of permeability was less dramatic in animals treated with anti-MCP-1 and anti-RANTES antibody, which demonstrated permeability decreases of 15% and 16%, respectively (p < 0.02). Lung neutrophil accumulation was reduced in animals receiving anti-MIP-1alpha antibody (p < 0.005) but was unchanged in animals receiving either anti-MCP-1 or anti-RANTES. Bronchoalveolar lavage leukocyte content was also reduced by treatment with anti-MIP-1alpha (p < 0.003) and was unchanged in anti-MCP-1-treated and anti-RANTES-treated animals. MIP-1alpha treatment decreased tumor necrosis factor-alpha messenger RNA in injured left lungs.. MIP-1alpha is functionally significant in the development of LIRI. It likely exerts its effects in part by mediating the expression of proinflammatory and antiinflammatory cytokines and influencing tissue neutrophil recruitment. MCP-1 and RANTES seem to play relatively minor roles in the development of direct LIRI.

Topics: Animals; Antibodies; Blotting, Northern; Blotting, Western; Bronchoalveolar Lavage Fluid; Capillary Permeability; Chemokine CCL2; Chemokine CCL3; Chemokine CCL4; Chemokine CCL5; Chemokines, CC; Leukocyte Count; Lung Diseases; Macrophage Inflammatory Proteins; Neutrophil Infiltration; Peroxidase; Rats; Rats, Long-Evans; Reperfusion Injury; RNA

This study was carried out to elucidate whether the protective activity of (-)-epicatechin 3-O-gallate (ECg) against excessive peroxynitrite (ONOO(-)) production, is distinct from the activity of several well-known free radical inhibitors, the ONOO(-) inhibitors ebselen and uric acid, the superoxide anion (O(2)(-)) scavenger copper zinc superoxide dismutase (CuZnSOD) and the selective inducible nitric oxide synthase inhibitor L-N(6)-(1-iminoethyl)lysine hydrochloride (L-NIL). To generate ONOO(-), male Wistar rats (n = 6/group) were subjected to ischaemia-reperfusion process together with lipopolysaccharide (LPS) injection. Although ECg did not scavenge the ONOO(-) precursors nitric oxide (NO) and O(2)(-), it reduced the 3-nitrotyrosine level, a property similar to that of uric acid, but distinct from L-NIL. In addition, the elevation in myeloperoxidase activity was reversed by the administration of ECg, uric acid and SOD, but not by that of L-NIL. Furthermore, ECg was the more potent scavenger of the ONOO(-) decomposition product, the hydroxyl radical (*OH), than any other free radical inhibitor tested. The LPS plus ischaemia-reperfusion process resulted in renal dysfunction, estimated by measuring the parameters of renal function--serum urea nitrogen and creatinine levels. However, administration of ECg ameliorated renal dysfunction more than that of the other free radical inhibitors. Moreover, ECg reduced the excessive uric acid level, while the others did not, suggesting a property of ECg distinct from the others. Furthermore, proteinuria, which was demonstrated by the low- and high-molecular weight (LMW and HMW) protein bands of the sodium dodecyl sulfate-polyacrylamide gel electrophoresis pattern, caused by LPS plus ischaemia-reperfusion, was attenuated by administration of ECg and L-NIL, after which the HMW band intensities decreased and LMW protein bands were absent. This study indicates that, in an in-vivo model of ONOO(-) generation, ECg, L-NIL and uric acid exert stronger protective activity against ONOO(-)-induced oxidative damage than SOD and ebselen, and that the mechanism whereby ECg protects against ONOO(-) is distinct from that of L-NIL or uric acid.

Topics: Animals; Azoles; Blood Urea Nitrogen; Catechin; Copper; Creatinine; Disease Models, Animal; Dose-Response Relationship, Drug; Free Radical Scavengers; Isoindoles; Japan; Kidney; Lipopolysaccharides; Lysine; Male; Nitric Oxide; Organoselenium Compounds; Peroxidase; Phytotherapy; Plant Extracts; Plant Roots; Proteinuria; Rats; Rats, Wistar; Reperfusion Injury; Rheum; Superoxide Dismutase; Tyrosine; Uric Acid; Zinc

We studied whether melatonin is able to reduce organ damage during renal ischemia/reperfusion via its effects on the oxidative response in early and late reperfusion.. Renal ischemia/reperfusion injury (I/R) was induced in two groups of rats by 75 min occlusion of the left renal artery and vein and right nephrectomy, followed by reperfusion. The formation of reactive oxygen species was evaluated in the early reperfusion phase (60 min) by lipid peroxidation products and glutathione assay. In the late reperfusion phase (24 h) tissue neutrophil infiltration, inducible nitric oxide synthase (iNOS) gene expression, and histopathology were evaluated. Groups received either systemic melatonin (MEL) or normal saline (NS). There were two nonischemic sham control groups, one with and another without melatonin (S+MEL and S).. Creatinine was higher in the NS group at all times. A reduction in glutathione and increases in lipid peroxidation products and myeloperoxidase activity induced by I/R indicated renal injury involving reactive oxygen formation. Melatonin reversed this oxidant response and reduced the rise in creatinine and iNOS expression. Seven-day group survivals were 5/10 for NS, 8/10 for MEL, and 10/10 for both Sham groups.. Exogenous melatonin is able to preserve renal functional status following I/R-induced injury by increasing glutathione and reducing lipid peroxidation in the early reperfusion phase, without any apparent effect on neutrophil infiltration in the late reperfusion phase.

Topics: Animals; Creatinine; Glutathione; Kidney; Lipid Peroxidation; Male; Melatonin; Necrosis; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Rats; Rats, Sprague-Dawley; Renal Circulation; Reperfusion Injury

Interleukin-6 (IL-6) is a pleiotropic acute reactant cytokine involved in inflammatory responses. To explore the role of IL-6 in inflammation, this study examined the efficacy of exogenous IL-6 in preventing intestinal ischemia/reperfusion (I/R) injury associated with small bowel transplantation (SBTx). Syngenic orthotopic SBTx was performed in Lewis rats after 6-h graft preservation in University of Wisconsin (UW) at 4 degrees C. IL-6 mutein (IL-6m, 500 microg/kg), a recombinant molecular variant of human IL-6, was subcutaneously given to donors 2 h before harvesting (IL-6mD) or to excised grafts by luminal infusion (IL-6mG). Animal survival was 100% and 75% in IL-6mD (p<0.05 vs. control) and IL-6mG groups, respectively, compared with 64.3% in untreated controls. The severity of I/R injury (e.g. epithelial denudation, villous congestion) was reduced with IL-6m, in addition to a striking increase in re-epithelization. With IL-6m, neutrophil extravasation was markedly reduced in intestinal grafts and in remote organs (e.g. lung). IL-6m mediated anti-inflammatory effects through the inhibition of I/R-induced up-regulation of intragraft and circulating IL-1-beta, tumor necrosis factor-alpha (TNF-alpha) and IL-6. IL-6m also increased intestinal graft tissue blood flow. These results show that IL-6 is effective in protecting the intestine from cold I/R injury by maintaining graft blood flow and reducing pro-inflammatory cytokine up-regulation and neutrophil infiltration.

Topics: Acute Disease; Animals; Benzothiazoles; Blotting, Western; Cytokines; Diamines; Immunohistochemistry; Inflammation; Interleukin-1; Interleukin-6; Intestinal Mucosa; Intestines; Lung; Male; Mutation; Neutrophils; Organ Transplantation; Organic Chemicals; Peroxidase; Quinolines; Rats; Rats, Inbred Lew; Reperfusion Injury; Repressor Proteins; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Suppressor of Cytokine Signaling 3 Protein; Suppressor of Cytokine Signaling Proteins; Time Factors; Transcription Factors; Tumor Necrosis Factor-alpha; Up-Regulation

Lung injury induced by ischemia-reperfusion is the main cause of early graft failure after lung transplantation, which may result from oxygen-free radicals, inflammatory cytokine production, and polymorphonuclear leukocyte accumulation into the interstitium, resulting in severe lung edema. Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) belongs to the nuclear receptor superfamily and has an anti-inflammatory effect by preventing the activation of transcription factors such as nuclear factor-kappaB (NF-kappaB). NF-kappaB regulates the expression of many genes of early response products in the development of acute inflammation. We examined the effects of pioglitazone, a synthetic ligand of PPAR-gamma, against lung ischemia-reperfusion injury in rats.. The left lungs of male Wistar rats were rendered ischemic for 90 min and then reperfused for 2 h. Treated animals received pioglitazone (10 mg/kg) 2 h before induction of ischemia. Lung injury was quantified in terms of lung microvascular permeability (Evans blue dye extravasation), tissue lipid peroxidation (thiobarbituric acid reactive substances), and tissue polymorphonuclear leukocyte accumulation (myeloperoxidase activity). The tissue concentrations of tumor necrosis factor-alpha (TNF-alpha) and cytokine-induced neutrophil chemoattractant-1 (CINC-1) were also measured. Statistical analyses were performed by one-way analysis of variance, followed by Sheffe's multiple comparison test.. The lung vascular permeability in pioglitazone-treated animals was reduced by 55% of the increase of Evans blue dye extravasation relative to control animals (P=0.003). The protective effects of pioglitazone treatment were correlated with the reduction by 79% of the increase of thiobarbituric acid reactive substances (P=0.045) and the reduction by 58% of myeloperoxidase activity increase (P<0.001). The production of TNF-alpha was reduced by 63% of the increase (P<0.001) and the reduction of CINC-1 was 45% (P<0.001). Pioglitazone did not affect the lung in the sham animals.. Pioglitazone treatment before ischemia attenuated lung ischemia-reperfusion injury in rats. The mechanism of these protective effects involves inhibition of the production of proinflammatory cytokines, polymorphonuclear leukocyte accumulation, and tissue lipid peroxidation, resulting in reduced lung edema.

Topics: Animals; Capillary Permeability; Cytokines; Ligands; Lipid Peroxidation; Lung; Male; Microcirculation; Peroxidase; Pioglitazone; Protective Agents; Rats; Rats, Wistar; Receptors, Cytoplasmic and Nuclear; Reperfusion Injury; Respiratory Distress Syndrome; Thiazolidinediones; Transcription Factors

We have shown that both intraischemic hypothermia and hypertonic saline resuscitation provide dramatic protection against gut ischemia/reperfusion (I/R) injury that is in part mediated by heme oxygenase-1 (HO-1). We therefore hypothesized that induction of HO-1 by hemin would lessen damage and improve function after gut I/R.. Male Sprague-Dawley rats were treated with 50 micromol/kg hemin (HO-1 inducer ferric protoporphyrin IX chloride) sq or vehicle 2 h before superior mesenteric artery occlusion for 60 min or sham laparotomy. After 6 h of reperfusion, transit was determined by quantitation of percentage of tracer in 10 equal segments of small intestine 30 min following injection into the duodenum (expressed as mean geometric center). Ileum was harvested for assessment of mucosal histologic injury (Chiu score 0-5 by blinded observer), myeloperoxidase activity (MPO, index of inflammation), and HO-1 protein expression.. Hemin treatment was associated with increased HO-1 protein expression, lessened mucosal injury, decreased MPO activity, and improved intestinal transit following gut I/R.. These data corroborate that HO-1 plays an important role in protecting the gut against I/R-induced injury.

Topics: Animals; Enzyme Induction; Gastrointestinal Transit; Heme Oxygenase (Decyclizing); Heme Oxygenase-1; Hemin; Intestinal Mucosa; Intestines; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Arrhythmia during ischemia and reperfusion is still an intriguing problem in cardiovascular medicine. Leukocytes infiltrating the ischemic region play an important pathophysiological role. The effects of soluble sialyl-Lewis-X analogues Hoe934553 and Hoe943644, which may inhibit leukocyte-endothelial interaction, were investigated.. Isolated rabbit hearts were perfused with Tyrode solution according to the Langendorff technique. Polymorphic neutrophilic granulocytes (PMN) were isolated from autologous peripheral blood. After 60 min equilibration PMN (n = 7) or vehicle (n = 7) were infused with or without concomitant treatment with Hoe934553 (n = 6) and Hoe943644 (n = 6). Five minutes after the start of the PMN infusion the left descending coronary artery was occluded for 30 min followed by 30 min of reperfusion. Activation and repolarization waves were recorded at 256 sites using a computerized mapping system.. Ventricular fibrillation (VF) in 4/7 PMN-treated hearts was found, while in PMN-free hearts no VF occurred. Treatment with Hoe934553 and Hoe943644 completely prevented VF. PMN largely enhanced the dispersion of action potential duration during reperfusion. This PMN effect was completely prevented by both drugs. Myeloperoxidase assay showed reduced activity in Hoe934553 and Hoe943644 treated hearts.. Sialyl-Lewis-X analogues (Hoe934553, Hoe943644) can antagonize PMN infiltration and PMN-induced VF in the course of ischemia and reperfusion.

Topics: Animals; Arrhythmias, Cardiac; Coronary Circulation; Disease Models, Animal; Electrophysiologic Techniques, Cardiac; Heart Conduction System; Heart Ventricles; Leukocytes; Male; Models, Cardiovascular; Oligosaccharides; Peroxidase; Rabbits; Reperfusion Injury; Sialyl Lewis X Antigen; Time Factors; Ventricular Pressure

Ischemia-reperfusion of the intestine produces a set of inflammatory mediators, the origin of which has recently been shown to involve pancreatic digestive enzymes. Matrix metalloproteinase-9 (MMP-9) participates in a variety of inflammatory processes including myocardial, hepatic, and pancreatic ischemia-reperfusion. In the present study, we explore the role of neutrophil-derived MMP-9 in acute intestinal ischemia-reperfusion and its interaction with pancreatic trypsin. Male Sprague-Dawley rats were subjected to 45 minutes of superior mesenteric arterial occlusion followed by 90 minutes of reperfusion. In situ zymography of the proximal jejunum reveals increased gelatinase activity in the intestinal wall after ischemia-reperfusion. Gel electrophoresis zymography and immunofluorescence co-localization suggests that this gelatinase activity is derived from MMP-9 released from infiltrating neutrophils. The role of intraluminal trypsin in this process was investigated using an in vivo isolated jejunal loop model of intestinal ischemia-reperfusion. Trypsin increased the inflammatory response after reperfusion, with an augmented neutrophil infiltration of the intestinal wall. Furthermore, trypsin stimulated a rapid conversion of neutrophil-released proMMP-9 into the lower molecular weight enzymatically active MMP-9. This process represents a powerful in vivo pathophysiological mechanism for trypsin-induced MMP-9 activation and is likely to play a central role in the development of acute intestinal inflammation and shock.

Topics: Animals; Blotting, Western; Catheterization; Enzyme Activation; Gelatin; Humans; Inflammation; Jejunum; Male; Matrix Metalloproteinase 9; Mesenteric Arteries; Microscopy, Fluorescence; Neutrophils; Pancreas; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Shock; Trypsin

Tumor necrosis factor-alpha is a proinflammatory mediator required for the development of experimental lung ischemia-reperfusion injury. The alveolar macrophage is a rich source of tumor necrosis factor-alpha in multiple models of acute lung injury. The present study was undertaken to determine whether the alveolar macrophage is an important source of tumor necrosis factor-alpha in lung ischemia-reperfusion injury and whether suppression of its function protects against injury.. Left lungs of Long-Evans rats underwent normothermic ischemia for 90 minutes and reperfusion for up to 4 hours. Treated animals received gadolinium chloride, a rare earth metal that inhibits macrophage function. Injury was quantitated via lung tissue neutrophil accumulation (myeloperoxidase content), lung vascular permeability, and bronchoalveolar lavage fluid leukocyte, cytokine, and chemokine content. Separate samples were generated for immunohistochemistry.. Tumor necrosis factor-alpha secretion occurred at 15 minutes of reperfusion and was localized to the alveolar macrophage by immunohistochemistry. In gadolinium-treated animals, lung vascular permeability was reduced by 66% at 15 minutes (P <.03) of reperfusion and by 34% at 4 hours (P <.02) of reperfusion. Suppression of macrophage function resulted in a 35% reduction in lung myeloperoxidase content (P <.03) and similar reductions in bronchoalveolar lavage leukocyte accumulation. Tumor necrosis factor-alpha and microphage inflammatory protein-1alpha protein levels were markedly reduced in the bronchoalveolar lavage of gadolinium-treated animals by enzyme-linked immunosorbent assay.. The alveolar macrophage secretes tumor necrosis factor-alpha protein by 15 minutes of reperfusion, which orchestrates the early events that eventually result in lung ischemia-reperfusion injury at 4 hours. Gadolinium pretreatment markedly reduces tumor necrosis factor-alpha elaboration, resulting in significant protection against lung ischemia-reperfusion injury.

Topics: Animals; Anti-Inflammatory Agents; Apoptosis; Bronchoalveolar Lavage Fluid; Capillary Permeability; Caspase 3; Caspases; Chemokine CCL4; Enzyme-Linked Immunosorbent Assay; Gadolinium; Immunohistochemistry; Leukocyte Count; Lung; Lung Diseases; Macrophage Inflammatory Proteins; Macrophages, Alveolar; Neutrophils; Peroxidase; Rats; Rats, Long-Evans; Reperfusion Injury; Tumor Necrosis Factor-alpha

Alpha chemokines function predominantly to recruit and activate neutrophils, which are important effectors of acute lung injury. This study evaluated whether blockade of 2 potent alpha chemokines, macrophage inflammatory protein-2 (MIP-2) and cytokine-induced neutrophil chemoattractant (CINC), is protective against lung ischemia-reperfusion injury in a warm in situ hilar clamp model.. Left lungs of Long-Evans rats underwent normothermic ischemia for 90 minutes and reperfusion for up to 4 hours. Treated animals received antibodies to MIP-2 or CINC immediately prior to reperfusion. Lung injury was quantitated by vascular permeability to (125)I-radiolabeled bovine serum albumin, lung tissue neutrophil sequestration (myeloperoxidase [MPO] content), and alveolar leukocyte content in bronchoalveolar lavage (BAL) fluid. CINC and MIP-2 mRNA expression were assessed by northern blot, while ribonuclease protection assays were performed to evaluate mRNA expression for a number of early response cytokines. MIP-2 and CINC protein expression in injured lungs was determined by immunoblotting.. Treatment with antibodies to CINC or MIP-2 was associated with significant protection against increases in vascular permeability, MPO content and alveolar leukocyte sequestration in injured lungs. Expression of CINC and MIP-2 mRNA peaked after 2 hours of reperfusion in injured lungs, and protein levels were evident on immunoblotting after 3 hours of reperfusion. Neither CINC nor MIP-2 blockade appeared to modulate cytokine mRNA expression.. CINC and MIP-2 are important mediators involved in direct lung ischemia-reperfusion injury. They appear to function by modulating neutrophil recruitment, but not inflammatory cytokine release.

Topics: Animals; Blotting, Northern; Blotting, Western; Bronchoalveolar Lavage; Capillary Permeability; Chemokine CXCL2; Chemokines, CXC; Disease Models, Animal; Intercellular Signaling Peptides and Proteins; Lung; Peroxidase; Rats; Rats, Long-Evans; Reperfusion Injury

The purpose of this study was to examine the potential role of substance P in accumulation of neutrophils in the lung following hepatic ischemia/reperfusion.. Male C57BL/6 mice (8-10 weeks of age) were subjected to either sham surgery, partial hepatic ischemia with or without reperfusion, or intratracheal administration of saline or 1 ng substance P. Lung neutrophil accumulation was assessed by tissue content of myeloperoxidase. Activation of the transcription factor, NF-kappaB, was determined by electrophoretic mobility shift assay. Levels of substance P and macrophage inflammatory protein-2 (MIP-2) in bronchoalveolar lavage (BAL) fluid was measured using enzyme-linked immunosorbent assays.. Significant pulmonary neutrophil accumulation was observed just prior to hepatic reperfusion in association with increased BAL levels of substance P. Intratracheal administration of substance P resulted in a similar pattern of neutrophil accumulation which was associated with activation of NF-kappaB and increased BAL levels of the chemokine, MIP-2.. The data suggest that hepatic ischemia causes substance P release in the lung which activates NF-kappaB leading to the production of MIP-2 and accumulation of neutrophils.

Topics: Animals; Bronchoalveolar Lavage Fluid; Chemokine CXCL2; Enzyme Activation; Enzyme-Linked Immunosorbent Assay; Inflammation; Liver; Lung; Male; Mice; Mice, Inbred C57BL; Monokines; Neuropeptides; Neutrophils; NF-kappa B; Peroxidase; Reperfusion Injury; Substance P; Time Factors

We previously demonstrated that intravenous poly (ADP) ribose synthetase (PARS) inhibition protects against experimental lung ischemia reperfusion injury (LIRI) in an in situ, hilar occlusion model. This study determined its efficacy when administered intratracheally (IT).. Left lungs of rats were rendered ischemic for 90 minutes, and reperfused for up to 4 hours. Treated animals received INO-1001, a PARS inhibitor, intratracheally 30 minutes before ischemia, while controls were given IT vehicle at equivalent volumes. All groups contained at least 4 animals. Lung injury was quantitated utilizing vascular permeability to radiolabeled albumin, tissue myeloperoxidase (MPO) content, alveolar leukocyte cell counts, and arterial pO(2) at 4 hours of reperfusion. Electrophoretic mobility shift assays (EMSA) assessed the nuclear translocation of NFkappaB and AP-1 in injured left lungs, while ELISAs quantitated secreted cytokine induced neutrophil chemoattractant (CINC) and MCP-1 protein in bronchoalveolar lavage fluid.. Intratracheal PARS inhibition was 73% (p < 0.0001) and 87% (p < 0.0001) protective against increases in vascular permeability and alveolar leukocyte accumulation, respectively, and improved arterial pO(2) (p < 0.0004) at 4 hours of reperfusion. Myeloperoxidase (MPO) activity in treated lungs was reduced by 70% (p < 0.02). The nuclear translocation of NFkappaB and AP-1 was attenuated at 15 minutes of reperfusion, and the secretion of CINC and MCP-1 (p < 0.05) protein into the alveolus was diminished at 4 hours of reperfusion.. Intratracheal INO-1001 protects against experimental LIRI. The reduction in secreted chemokine protein at 4 hours of reperfusion appears to be mediated at the pretranscriptional level through attenuated NFkappaB and AP-1 activation. This route may optimize future donor organ management and improve lung recipient outcomes.

Topics: Animals; Bronchoalveolar Lavage Fluid; Capillary Permeability; Chemokines, CXC; Electrophoretic Mobility Shift Assay; Enzyme Inhibitors; Intercellular Signaling Peptides and Proteins; Intubation, Intratracheal; Lung; NF-kappa B; Oxygen; Peroxidase; Poly(ADP-ribose) Polymerase Inhibitors; Radiation-Sensitizing Agents; Rats; Rats, Long-Evans; Reperfusion Injury; Transcription Factor AP-1

Poly(ADP-ribose) polymerase (PARP), a nuclear enzyme activated by strand breaks in DNA, plays an important role in the tissue injury associated with ischemia-reperfusion and inflammation. Splanchnic artery occlusion and reperfusion causes an enhanced formation of reactive oxygen species which contribute to the pathophysiology of shock. The aim of the present study was to investigate the effects of 5-aminoisoquinolinone (5-AIQ), a potent water-soluble inhibitor of poly(ADP-ribose) polymerase (PARP), in the pathogenesis of splanchnic artery occlusion shock. Splanchnic artery occlusion shock was induced in rats by clamping both the superior mesenteric artery and the celiac artery for 45 min, followed thereafter by release of the clamp (reperfusion). At 60 min after reperfusion, all animals were sacrificed for histological examination and biochemical studies. Treatment of rats with 5-AIQ (3 mg/kg i.v.), attenuated the fall of mean arterial blood pressure caused by splanchnic artery occlusion shock. 5-AIQ also attenuated the ileum injury as well as the increase in the tissue levels of myeloperoxidase and malondialdehyde caused by splanchnic artery occlusion shock in the ileum. The immunohistochemical examination also demonstrated a marked increase in the immunoreactivity to PAR, nitrotyrosine, and intercellular adhesion molecule (ICAM-1) in the necrotic ileum from splanchnic artery occlusion-shocked rats. 5-AIQ treatment significantly reduced the increase of positive staining for PAR, nitrotyrosine and ICAM-I. In conclusion, these results show that 5-AIQ, a new water-soluble potent inhibitor of poly(ADP-ribose) polymerase, exerts multiple protective effects in splanchnic artery occlusion/reperfusion shock.

Topics: Animals; Celiac Artery; Disease Models, Animal; Intercellular Adhesion Molecule-1; Intestine, Small; Ischemia; Isoquinolines; Lipid Peroxidation; Male; Malondialdehyde; Mesenteric Artery, Superior; Mesenteric Vascular Occlusion; Peroxidase; Poly(ADP-ribose) Polymerase Inhibitors; Rats; Rats, Sprague-Dawley; Reperfusion; Reperfusion Injury; Solubility; Tyrosine; Water

Heme-oxygenase-1 (HO-1) has been shown to play an important role in oxidative stress, and recent studies indicate that it is a graft survival protein in cardiac and liver transplant models. Our laboratory previously found HO-1 to be increased in human lung allografts with acute cellular rejection (ACR) and in active obliterative bronchiolitis. To better understand the role of HO-1 in ACR we studied the relationship between HO-1 expression and ACR in a rodent model of lung transplantation.. Orthotopic left lung transplantation was performed from Lewis (donor) to Sprague-Dawley (recipient) rats, and ACR (Grade A0 to A4) was evaluated at days 3, 5, and 7. HO-1 expression was assessed by immunohistochemistry and Western analysis, and compared with the degree of ACR. Myeloperoxidase staining was evaluated as an indirect measure of oxidant stress. Donors and recipients were also treated with either an inhibitor of HO activity, tin protoporphyrin or an inducer, cobalt protoporphyrin, and the severity of ACR was compared with that in untreated allografts.. HO-1 expression was elevated in transplanted versus native lungs or isografts, and the degree of elevation was closely correlated with ACR grade (p < 0.001). Similarly, myeloperoxidase expression increased with time and severity of ACR. Administration of the metalloporphyrins, tin protoporphyrin and cobalt protoporphyrin, produced no significant difference in the degree of ACR, but did alter the severity of ischemia-reperfusion injury.. Similar to what occurs in human lung transplantation, HO-1 expression is increased in a rodent lung transplant model of ACR and correlates with the severity of rejection. Altering its expression does not appear to affect the degree of ACR.

Topics: Animals; Graft Rejection; Heme Oxygenase (Decyclizing); Heme Oxygenase-1; Humans; Immunohistochemistry; Lung Transplantation; Male; Membrane Proteins; Oxidative Stress; Peroxidase; Rats; Rats, Inbred Lew; Rats, Sprague-Dawley; Reperfusion Injury

Pulmonary preservation for transplantation is associated with ischemia reperfusion injury resulting in endothelial cell and surfactant dysfunction. The purpose of the study was to compare two extracellular type solutions, low potassium dextrane (LPD) and Celsior in their ability of ameliorating lung ischemia reperfusion injury.. In 12 donor pigs, the left lung was perfused with either LPD (n = 6) or Celsior (n = 6) solution. After 24 h cold storage, the lungs were transplanted into 12 recipient animals. After reperfusion of the left lung, the right pulmonary artery and bronchus were clamped. Bronchoalveolar lavage fluid (BALF) was obtained before the surgical procedure and 2 h after reperfusion. Surfactant activity was measured from BALF using a pulsating bubble surfactometer. Hemodynamic and respiratory parameters were assessed in 30-min intervals for 7 post-operative hours.. In both study groups two of six animals died from severe ischemia reperfusion injury, thus survival did not differ between groups. Rise of pulmonary vascular resistance index (P = 0.01) and sequestration of neutrophiles (P = 0.08) was less pronounced in Celsior group when compared to LPD animals. A difference in surfactant activity between both groups was not evident after 2 h of reperfusion.. Both solutions might provide safe pulmonary preservation for 24 h of cold ischemia. While surfactant activity was affected to the same extent in both groups, Celsior solution provided slightly superior endothelial preservation.

Topics: Animals; Bronchoalveolar Lavage Fluid; Cold Temperature; Dextrans; Disaccharides; Electrolytes; Female; Glucose; Glutamates; Glutathione; Hemodynamics; Histidine; Lung; Lung Transplantation; Mannitol; Organ Preservation; Organ Preservation Solutions; Peroxidase; Pulmonary Edema; Reperfusion Injury; Respiratory Physiological Phenomena; Surface Properties; Swine

To investigate the effects of sodium beta-aescin on neutrophil migration and expression of adhesion molecules (ICAM-1 and E-selectin) after middle cerebral artery occlusion (MCAO) in rats.. Rats were pretreated with sodium beta-aescin for 7 d and then subjected to cerebral ischemia/reperfusion (I/R) injury induced by an MCAO. After a 2-h ischemia and a 24-h reperfusion, the infarct volume and neurological deficit were determined by the method of TTC staining and the Longa's score. The effect of sodium beta-aescin on the migration of neutrophils was evaluated by measuring the activity of myeloperoxidase (MPO) enzyme. The expressions of adhesion molecules were determined by immunohistochemistry and Western blot.. Sodium beta-aescin significantly reduced the cerebral infarct volume and ameliorated the neurological deficit (P<0.05 or P<0.01). The MPO activity and the expressions of ICAM-1 and E-selectin in the vehicle-treated rats were increased significantly (P<0.01) after cerebral I/R. After treatment with sodium beta-aescin, the enzymatic activity of MPO and the expressions of these adhesion molecules were significantly reduced compared with the vehicle-treated group (P<0.05 or P<0.01).. Sodium beta-aescin can attenuate brain injury, down-regulate the protein expressions of ICAM-1 and E-selectin, and reduce the migration of neutrophils after cerebral I/R.

Topics: Aesculus; Animals; Cell Movement; Cerebral Infarction; Down-Regulation; E-Selectin; Escin; Infarction, Middle Cerebral Artery; Intercellular Adhesion Molecule-1; Male; Neuroprotective Agents; Neutrophils; Peroxidase; Plants, Medicinal; Rats; Rats, Sprague-Dawley; Reperfusion Injury

We investigated the effect of two inhibitors of nitric oxide (NO) synthesis, N(w)-nitro-L-arginine methyl ester (L-NAME) and aminoguanidine, on lung inflammation caused by intestinal ischemia/reperfusion in rats. Relative to the sham-operated rats, intestinal ischemia/reperfusion (ischemia: 45 min; reperfusion: 30 min, 2 and 4 h) induced neutrophil recruitment (increased myeloperoxidase activity) and increased microvascular permeability (Evans blue dye extravasation) in the lungs and increased tumor necrosis factor (TNF) levels in the serum (L-929 cytotoxicity assay). L-NAME given before the ischemia exacerbated neutrophil accumulation, plasma extravasation, serum TNF and caused death of the animals, which was prevented by concomitant injection of L-arginine. Lung and systemic effects of intestinal ischemia/reperfusion were not modified when L-NAME was given just before reperfusion. Treatment with aminoguanidine inhibited plasma extravasation without affecting the other parameters evaluated. Dexamethasone reduced all the parameters. Our results indicate that during intestinal ischemia/reperfusion both constitutive and inducible NO synthases are called to exert a differential modulatory effect on lung inflammation and that maintenance of adequate levels of NO during ischemia is essential for the animals survival.

Topics: Animals; Anti-Inflammatory Agents; Capillary Permeability; Dexamethasone; Guanidines; Inflammation; Intestines; Lung; Male; Neutrophil Infiltration; NG-Nitroarginine Methyl Ester; Nitric Oxide; Peroxidase; Pulmonary Circulation; Rats; Rats, Wistar; Regional Blood Flow; Reperfusion Injury; Tumor Necrosis Factor-alpha

A newly synthesized free-radical scavenger, MCI-186 (3-methyl-1-phenyl-2-pyrazolin-5-1), was recently approved in Japan for treating acute brain infarction. The purpose of this study was to investigate whether or not MCI-186 is effective in reducing ischemia-reperfusion injury in the extremities.. Warm ischemia was sustained for 4 hours. The animals were divided into 4 groups: (1) sham group, (2) control group (saline injection), (3) MCI group (MCI-186 injection), and (4) EPC group (EPC-K1 [(l-ascorbic acid 2-[3,4-dihydro-2, 5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-1-benzopyran-6-yl hydrogen phosphate] potassium salt], a hydroxyl-radical scavenger, injection). Wet and dry (W/D) weights of the gastrocnemius and tibialis anterior muscles, muscle contractile function, and serum levels of creatine phosphokinase (CPK), lactate dehydrogenase (LDH), glutamic oxaloacetic transminase (GOT), and mitochondrial glutamic oxaloacetic transminase (GOT-m) were measured after 24 h of reperfusion. The cytotoxic aldehydes malondialdehyde and 4-hydroxy-2-nonenal as indices of lipid peroxidation (LPO), and neutrophil-specific enzyme myeloperoxidase (MPO) as an index of neutrophil infiltration, were measured in the gastrocnemius muscle.. Contractile functions in the MCI and EPC groups were significantly better than in the control group. In the tibialis anterior muscle, the contractile function was better in the MCI group than in the EPC group. W/D ratios and serum levels of CPK, LDH, GOT, and GOT-m were lower in the sham and MCI groups than in the control group. Levels of LPO and MPO activity were significantly lower in the MCI and EPC groups than in the control group. Histological findings demonstrated that inflammatory tissue reactions rarely occurred in the MCI group.. MCI-186 is effective in preventing ischemia-reperfusion injury in extremities. MCI-186 seems to have promise as a therapeutic agent, because it prevents ischemia-reperfusion injury even in the tibialis anterior muscle, which contains fast-twitch glycolytic fibers, known to be very susceptible to ischemic insult.

Topics: Amputation, Surgical; Animals; Antioxidants; Antipyrine; Body Water; Edaravone; Enzymes; Free Radical Scavengers; Hindlimb; Lipid Peroxidation; Male; Muscle, Skeletal; Peroxidase; Rats; Rats, Inbred Lew; Reperfusion Injury

We previously reported that nitric oxide (NO) derived from endothelial NO synthase (NOS) increased endothelial prostacyclin (PGI(2)) production in rats subjected to hepatic ischemia-reperfusion (I/R). The present study was undertaken to determine whether neutrophil elastase (NE) decreases endothelial production of PGI(2), thereby contributing to the development of I/R-induced liver injury by decreasing hepatic tissue blood flow in rats. Hepatic tissue levels of 6-keto-PGF(1alpha), a stable metabolite of PGI(2), were transiently increased and peaked at 1 h after reperfusion, followed by a gradual decrease until 3 h after reperfusion. Sivelestat sodium hydrochloride and L-658,758, two NE inhibitors, reduced I/R-induced liver injury. These substances inhibited the decreases in hepatic tissue levels of 6-keto-PGF(1alpha) at 2 and 3 h after reperfusion but did not affect the levels at 1 h after reperfusion. These NE inhibitors significantly increased hepatic tissue blood flow from 1 to 3 h after reperfusion. Both hepatic I/R-induced increases in the accumulation of neutrophils and the microvascular permeability were inhibited by these two NE inhibitors. Protective effects induced by the two NE inhibitors were completely reversed by pretreatment with nitro-l-arginine methyl ester, an inhibitor of NOS, or indomethacin. Administration of iloprost, a stable derivative of PGI(2), produced effects similar to those induced by NE inhibitors. These observations strongly suggest that NE might play a critical role in the development of I/R-induced liver injury by decreasing endothelial production of NO and PGI(2), leading to a decrease in hepatic tissue blood flow resulting from inhibition of vasodilation and induction of activated neutrophil-induced microvascular injury.

Topics: 6-Ketoprostaglandin F1 alpha; Animals; Capillary Permeability; Cephalosporins; Chemokines, CXC; Cyclooxygenase Inhibitors; Endothelium; Enzyme Inhibitors; Epoprostenol; Glycine; Iloprost; Indomethacin; Intercellular Signaling Peptides and Proteins; Leukocyte Elastase; Liver; Liver Circulation; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type III; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Sulfonamides; Transaminases; Vasodilator Agents

Restoration of normal perfusion pressure after resection of cerebral arteriovenous malformations (AVMs) is sometimes complicated by unexplained postoperative brain swelling and/or intracranial hemorrhage, which has been termed normal perfusion pressure breakthrough (NPPB). The precise mechanism of NPPB is still unclear. In this study, we investigated the time courses of blood-brain barrier (BBB) disruption, water content, neuronal apoptosis, myeloperoxidase (MPO) activity and superoxide dismutase (SOD) activity in the brain during restoration of normal perfusion pressure in a new rat model of chronic cerebral hypoperfusion associated with AVMs. Male Sprague-Dawley rats were randomly divided into either a sham-operated group, a control group, or a model group with reperfusion assessed at 1, 12, 24 and 72 h after restoration of normal perfusion pressure. BBB disruption was judged by extravasation of Evans blue (EB) dye. We observed that EB and water content in rat brains of the model group with reperfusion were significantly increased compared with the other groups. The most predominant increase occurred at 1 h after reperfusion, and the next at 24 h after reperfusion, representing biphasic changes which are similar to the pathological processes of acute cerebral ischemia/reperfusion injury. There was no difference of the percentage of apoptotic cells in rat brains between the sham-operated group and the control group using flow cytometry. No prominent apoptotic cells were found in the model group with reperfusion at 1 h. However, the percentage of apoptotic cells increased significantly in rat brains of the model group with reperfusion at 12 h, peaked at 24 h, and decreased at 72 h after reperfusion. Apoptotic cells were confirmed with electron microscopy and terminal deoxynuleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL). A significant enhancement of MPO activity in combination with reduction of SOD activity was seen at 12, 24 and 72 h in rat brains of the model group with reperfusion. Our data indicates that reperfusion after restoration of normal perfusion pressure with chronic cerebral hypoperfusion lead to secondary neuronal damage which may associate with cerebral ischemia/reperfusion injury.

Topics: Animals; Apoptosis; Blood-Brain Barrier; Brain; Cerebrovascular Circulation; Flow Cytometry; Functional Laterality; In Situ Nick-End Labeling; Intracranial Arteriovenous Malformations; Male; Microscopy, Electron; Neurons; Perfusion; Peroxidase; Rats; Reperfusion; Reperfusion Injury; Superoxide Dismutase; Time Factors

The role of 5-lipoxygenase (5-LOX) in the pathophysiology of renal ischemia/reperfusion (I/R) injury is not known. Here we investigate the effects of 1) the 5-LOX inhibitor zileuton and 2) 5-LOX gene knockout (5-LOX(-/-)) mice on renal dysfunction and injury caused by I/R of the kidney in mice. Wild-type mice treated with zileuton (3 mg/kg i.v.) or 5-LOX(-/-) mice were subjected to bilateral renal artery occlusion (30 min) followed by reperfusion (24 h). Plasma urea, creatinine, and aspartate aminotransferase (AST) were measured as markers of renal dysfunction and reperfusion injury. Kidneys were used for histological evaluation of renal injury. Renal myeloperoxidase activity was measured and used as an indicator of polymorphonuclear leukocyte (PMN) infiltration and renal expression of intercellular adhesion molecule-1 (ICAM-1) was determined using immunohistochemistry. Administration of zileuton before I/R significantly reduced the degree of renal dysfunction (urea, creatinine) and injury (AST, histology). In addition, zileuton reduced the expression of ICAM-1 and the associated PMN infiltration caused by I/R of the mouse kidney. Compared with wild-type mice, the degree of renal dysfunction, injury, and inflammation caused by I/R in 5-LOX(-/-) mice was also significantly reduced, confirming the pathophysiological role of 5-LOX in the development of renal I/R injury. We propose that 1) endogenous 5-LOX metabolites enhance the degree of renal injury, dysfunction, and inflammation caused by I/R of the kidney by promoting the expression of adhesion molecules, and 2) inhibitors of 5-LOX may be useful in the treatment of conditions associated with I/R of the kidney.

Topics: Animals; Arachidonate 5-Lipoxygenase; Disease Models, Animal; Hydroxyurea; Inflammation; Intercellular Adhesion Molecule-1; Ischemia; Kidney Diseases; Leukotriene B4; Lipoxygenase Inhibitors; Mice; Mice, Knockout; Neutrophils; Peroxidase; Reperfusion Injury

The effects of selective inhibitors of phosphodiesterase type IV (PDE4) on ischemia-reperfusion-induced gastric injuries were investigated in rats. Gastric ischemia was induced by applying a small clamp to the celiac artery, and reoxygenation was performed by removal of the clamp. Ischemia-reperfusion produced gastric hemorrhagic injuries and increased the content of the proinflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) and myeloperoxidase (MPO) activity in gastric mucosa. Rolipram (0.03-0.3 mg/kg, s.c.) and Ro-20-1724 (0.3-3 mg/kg, s.c.) prevented the development of gastric injury in a dose-dependent manner, and it also inhibited the increase in mucosal TNF-alpha content and MPO activity induced by ischemia-reperfusion. The anti-ulcer drug irsogladine (1-10 mg/kg, p.o.), which is known to possess a PDE4 inhibitory action, also inhibited the gastric injury produced by ischemia-reperfusion, as well as the increase in TNF-alpha levels and MPO activity. It is concluded that the ability of PDE4 inhibitors to inhibit cytokine TNF-alpha synthesis and the infiltration of polymorphonuclear leukocytes underlies their gastroprotective effects in ischemia-reperfusion-induced gastric injury. Our experiments suggest that drugs that inhibit PDE4 isoenzyme, such as the anti-ulcer drug irsogladine, may be a useful adjunct therapy for the treatment of the gastric damage that follows ischemia-reperfusion.

Topics: 3',5'-Cyclic-AMP Phosphodiesterases; 4-(3-Butoxy-4-methoxybenzyl)-2-imidazolidinone; Animals; Anti-Ulcer Agents; Cyclic Nucleotide Phosphodiesterases, Type 4; Dose-Response Relationship, Drug; Gastric Mucosa; Male; Omeprazole; Peroxidase; Phosphodiesterase Inhibitors; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Rolipram; Stomach Ulcer; Triazines; Tumor Necrosis Factor-alpha

Aortic ischemia-reperfusion (AIR) induced lung injury has already been documented. Kupffer cell blockage (KCB) with gadolinium chloride (GdCl3) has also been shown to attenuate remote organ damage caused by ischemia reperfusion. The present study was designed to examine the effect of GdCl3 in lung ischemia-reperfusion injury induced by aortic occlusion. Thirty-two rats were randomly allocated to four groups as follows: SHAM (Sham Laparotomy), SHAM+KCB, AIR, and AIR+KCB. An atraumatic microvascular clamp was placed across the infrarenal abdominal aorta just after its origin from the aorta for 30 minutes. The microvascular clamp on the infrarenal abdominal aorta was removed and reperfused for 60 minutes. GdCl3 was given 24 hours prior to the experiment. Malondialdehyde (MDA) level and myeloperoxidase (MPO) activity were assayed in lung tissues. MDA level and MPO activity in the AIR group were significantly higher than those in the other groups. When compared to AIR group, KCB with GdCl3 significantly decreased MDA level and MPO activity in the AIR+KCB group. These results suggest that GdCl3 attenuates the lung injury caused by AIR. The effects of GdCl3 on reduced lung damage may be mediated through significant decreases in both MDA level and MPO activity.

Topics: Animals; Anti-Inflammatory Agents; Aorta; Arterial Occlusive Diseases; Female; Gadolinium; Ischemia; Lung Diseases; Male; Malondialdehyde; Peroxidase; Rats; Rats, Wistar; Reperfusion; Reperfusion Injury

Inflammatory response following cerebral ischemia/reperfusion plays a key pathogenic role in ischemic cerebral damage. Nitric oxide (NO), cyclooxygenase-2 (COX-2) and myeloperoxidase (MPO) are important inflammatory mediators. Neuronal NO synthase (nNOS) is a major initial source of excessive NO during ischemia/reperfusion. Induction of COX-2 and infiltration of polymorphonuclear cells expressing MPO are critical factors in delayed inflammatory damage. Previously, we demonstrated that administration of melatonin before ischemia significantly reduced the infarct volume in a rat middle cerebral artery occlusion (MCAO) stroke model. In this study, we examined the effect of pretreatment with melatonin at 5 mg/kg on the immunoreactivity (ir) for nNOS, COX-2, MPO, and glial fibrillary acidic protein (GFAP) at 24, 48, and 72 hr after right-sided endovascular MCAO for 1 hr in adult male Sprague-Dawley rats. Melatonin did not affect the hemodynamic parameters. When compared with rats with sham MCAO, ischemia/reperfusion led to an ipsilateral increase in cells with positive ir for nNOS (similar at all times) and in ir-GFAP (similar at all times). Ischemia/reperfusion led to appearance of cells with positive ir for COX-2 (greatest at 24 hr with a tendency to increase again at 72 hr) or MPO (greatest at 24 hr). A single dose of melatonin significantly lessened the ipsilateral increase in cells with positive ir for nNOS, COX-2 or MPO, but did not influence the ipsilateral change in ir-GFAP. Our results suggest that melatonin treatment mediates neuroprotection against ischemia/reperfusion injury partly via inhibition of the consequential inflammatory response.

Topics: Animals; Antioxidants; Brain; Cyclooxygenase 2; Disease Models, Animal; Glial Fibrillary Acidic Protein; Immunohistochemistry; Infarction, Middle Cerebral Artery; Isoenzymes; Male; Melatonin; Neurons; Neuroprotective Agents; Nitric Oxide Synthase; Nitric Oxide Synthase Type I; Peroxidase; Prostaglandin-Endoperoxide Synthases; Rats; Rats, Sprague-Dawley; Reperfusion Injury

1. Neutrophils are thought to play a major role in the mediation of reperfusion injury. CXC chemokines are known inducers of neutrophil recruitment. Here, we assessed the effects of Repertaxin, a novel low molecular weight inhibitor of human CXCL8 receptor activation, on the local, remote and systemic injuries following intestinal ischaemia and reperfusion (I/R) in the rat. 2. Pre-incubation of rat neutrophils with Repertaxin (10(-11)-10(-6) m) inhibited the chemotaxis of neutrophils induced by human CXCL8 or rat CINC-1, but not that induced by fMLP, PAF or LTB(4), in a concentration-dependent manner. Repertaxin also prevented CXCL8-induced calcium influx but not CXCL8 binding to purified rat neutrophils. 2. In a model of mild I/R injury (30 min of ischaemia and 30 min of reperfusion), Repertaxin dose-dependently (3-30 mg kg(-1)) inhibited the increase in vascular permeability and neutrophil influx. Maximal inhibition occurred at 30 mg kg(-1). 4. Following severe I/R injury (120 min of ischaemia and 120 min of reperfusion), Repertaxin (30 mg kg(-1)) markedly prevented neutrophil influx, the increase in vascular permeability both in the intestine and the lungs. Moreover, there was prevention of haemorrhage in the intestine of reperfused animals. 5. Repertaxin effectively suppressed the increase in tissue (intestine and lungs) and serum concentrations of TNF-alpha and the reperfusion-associated lethality. 6. For comparison, we also evaluated the effects of an anti-CINC-1 antibody in the model of severe I/R injury. Overall, the antibody effectively prevented tissue injury, systemic inflammation and lethality. However, the effects of the antibody were in general of lower magnitude than those of Repertaxin. 7. In conclusion, CINC-1 and possibly other CXC chemokines, acting on CXCR2, have an important role during I/R injury. Thus, drugs, such as Repertaxin, developed to block the function of the CXCR2 receptor may be effective at preventing reperfusion injury in relevant clinical situations.

Topics: Animals; Anti-Inflammatory Agents; Antibodies, Blocking; Calcium; Capillary Permeability; Chemokine CXCL1; Chemokines, CXC; Chemotaxis, Leukocyte; Cytokines; Dose-Response Relationship, Drug; Hemoglobins; Inflammation; Intercellular Signaling Peptides and Proteins; Intestinal Mucosa; Intestines; Leukocyte Count; Lung; Male; Neutrophils; Peroxidase; Rats; Rats, Wistar; Receptors, Interleukin-8B; Reperfusion Injury; Sulfonamides

Impaired microvascular function during myocardial ischemia and reperfusion is associated with recruitment of polymorphonuclear neutrophils (PMN) and has been attributed to decreased bioavailability of nitric oxide (NO). Whereas myeloperoxidase (MPO), a highly abundant, PMN-derived heme protein facilitates oxidative NO consumption and impairs vascular function in animal models of acute inflammation, its capacity to function in this regard during human myocardial ischemia and reperfusion remains unknown. Plasma samples from 30 consecutive patients (61 +/- 14 years, 80% male) presenting with acute myocardial infarction were collected 9 +/- 4 h after vessel recanalization and compared to plasma from healthy control subjects (n = 12). Plasma levels of MPO were higher in patients than in control subjects (1.4 +/- 0.9 vs 0.3 +/- 0.2 ng/mg protein, respectively, p < 0.0001). The addition of hydrogen peroxide to patient plasma resulted in accelerated rates of NO consumption compared to control subjects (0.53 +/- 0.25 vs 0.068 +/- 0.039 nM/s/mg protein, respectively, p < 0.0001). Myocardial tissue from patients with the same pathology revealed intense recruitment of MPO-positive PMN localized along infarct-related vessels as well as diffuse endothelial distribution of non-PMN-associated MPO immunoreactivity. Endothelium-dependent microvascular function, as assessed by an acetylcholine-dependent increase in forearm blood flow in 75 patients with symptomatic coronary artery disease, inversely correlated with MPO plasma levels (r = -0.75, p < 0.005). Plasma from patients undergoing myocardial reperfusion contained increased levels of MPO, which catalytically consumed NO in the presence of H(2)O(2). Given the correlation between intravascular MPO levels and forearm vasomotor function in patients with coronary artery disease, MPO appears to be an important modulator of vasomotor function in inflammatory vascular disease and a potential therapeutic target for treatment.

Topics: Aged; Animals; Case-Control Studies; Enzyme-Linked Immunosorbent Assay; Female; Heme; Humans; Hydrogen Peroxide; Immunohistochemistry; Male; Middle Aged; Models, Biological; Myocardial Infarction; Myocardial Ischemia; Myocardium; Neutrophils; Nitric Oxide; Peroxidase; Platelet Endothelial Cell Adhesion Molecule-1; Rabbits; Regional Blood Flow; Reperfusion; Reperfusion Injury; Time Factors

Copaifera langsdorffii oleo-resin (CLOR) is a reputed herbal medicine used to combat gastrointestinal functional disorders. Our previous studies show that CLOR prevents gastric ulceration and promotes wound healing. This study examined the effects of CLOR on intestinal damage associated with mesenteric ischemia/reperfusion in rat. Wistar albino rats were divided into four groups of six in each. Group 1: Sham operated, Group 2: Vehicle + 45 min of ischemia followed by 60 min reperfusion (I/R), Groups 3 and 4: I/R + CLOR (200 and 400 mg /kg, p.o., respectively). All treatments were given 24 h, 12 h and 2 h before I/R. Animals were sacrificed at the end of reperfusion period and ileal tissue samples were obtained for biochemical analysis. Myeloperoxidase (MPO), an index of polymorphonuclear leukocytes; malondialdehyde (MDA), an end product of lipoperoxidation; catalase (CAT), an antioxidant enzyme; reduced glutathione (GSH), a key antioxidant; and nitrite, a marker of nitric oxide (NO) production were determined in ileum homogenates. The results show that I/R produces a significant increase in MDA content, MPO, and CAT activities with a significant decrease in GSH and an elevation in nitrite production, as compared to sham control. CLOR treatment caused significant attenuations in I/R-associated increases of MPO, MDA and CAT activities and on nitrite level. Besides, CLOR could effectively prevent the I/R-associated depletion of GSH. The data indicate that the oleo-resin has a protective action against I/R-induced intestinal tissue damage, which appeared to be, at least in part, due to an antioxidant and anti-lipid peroxidation mechanism.

Topics: Analysis of Variance; Animals; Balsams; Catalase; Glutathione; Ileum; Male; Malondialdehyde; Nitrites; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

In the present study, we used glucocorticoid-induced tumor necrosis factor (TNF) receptor family gene knockout (GITR-KO) mice to evaluate a possible role of GITR on the pathogenesis of splanchnic artery occlusion (SAO) shock, which was induced in mice by clamping the superior mesenteric artery and the celiac artery for 30 min, followed thereafter by release of the clamp (reperfusion). At 60 min after reperfusion, animals were killed for histological examination and biochemical studies. There was a marked increase in the lipid peroxidation in the ileum of the SAO-shocked, GITR wild-type (WT) mice after reperfusion. The absence of GITR significantly reduced the lipid peroxidation in the intestine. SAO-shocked WT mice developed a significant increase of ileum tissue, TNF-alpha, and myeloperoxidase activity and marked histological injury. SAO shock was also associated with a significant mortality (5% survival at 24 h after reperfusion). Reperfused ileum tissue sections from SAO-shocked WT mice showed positive staining for P-selectin, intercellular adhesion molecule 1 (ICAM-1), and E-selectin. The intensity and degree of P-selectin, E-selectin, and ICAM-1 were markedly reduced in tissue section from SAO-shocked, GITR-KO mice. SAO-shocked, GITR-KO mice also showed a significant reduction of the TNF-alpha production and neutrophil infiltration into the reperfused intestine, an improved histological status of the reperfused tissues, and an improved survival. Taken together, our results clearly demonstrate that GITR plays an important role in the ischemia and reperfusion injury and put forward the hypothesis that modulation of GITR expression may represent a novel and possible strategy.

Topics: Animals; Celiac Artery; Chemotaxis, Leukocyte; Disease Models, Animal; E-Selectin; Genetic Predisposition to Disease; Glucocorticoid-Induced TNFR-Related Protein; Ileum; Intercellular Adhesion Molecule-1; Lipid Peroxidation; Male; Mesenteric Artery, Superior; Mesenteric Vascular Occlusion; Mice; Mice, Knockout; P-Selectin; Peroxidase; Receptors, Nerve Growth Factor; Receptors, Tumor Necrosis Factor; Reperfusion Injury; Shock; Splanchnic Circulation; Survival Rate; Tumor Necrosis Factor-alpha; Up-Regulation

Compartment syndrome is a unique form of ischaemia of skeletal muscle which occurs despite patency of the large vessels. Decompression allows the influx of activated leucocytes which cause further injury. Vitamin C is a powerful antioxidant which concentrates preferentially in leucocytes and attenuates reperfusion-induced muscle injury. We have evaluated the use of pretreatment with oral vitamin C in the prevention of injury caused by compartment syndrome in a rat cremasteric muscle model. Acute and delayed effects of pretreatment with vitamin C were assessed at one and 24 hours after decompression of compartment syndrome. Muscle function was assessed electrophysiologically. Vascular, cellular and tissue inflammation was assessed by staining of intercellular adhesion molecule-1 (ICAM-1) and by determination of the activity of myeloperoxidase (MPO) in neutrophils and tissue oedema. Compartment syndrome impaired skeletal muscle function and increased the expression of ICAM-1, activity of MPO and muscle weight increased significantly. Pretreatment with vitamin C preserved muscle function and reduced the expression of ICAM-1, infiltration of the neutrophils and oedema.

Topics: Administration, Oral; Animals; Ascorbic Acid; Compartment Syndromes; Edema; Intercellular Adhesion Molecule-1; Muscle, Skeletal; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Reoxygenation of the ischemic tissue promotes the generation of various reactive oxygen metabolites (ROM) which are known to have deleterious effects on various cellular functions. This study was designed to determine the possible protective effect of mesna (2-Mercaptoethane Sulfonate) on renal ischemia/reperfusion (I/R) injury. Wistar albino rats were unilaterally nephrectomized, and 15 days later they were subjected to 45 min of renal pedicle occlusion followed by 6 h of reperfusion. Mesna (MESNA, 150 mg/kg, i.p.; an effective dose against I/R injury) or vehicle was administered twice, 15 min prior to ischemia and immediately before the reperfusion period. At the end of the reperfusion period, rats were killed by decapitation. Kidney samples were taken for histological examination or determination of the free radicals, renal malondialdehyde (MDA) and glutathione (GSH) levels, and myeloperoxidase (MPO) activity. Renal tissue collagen content, as a fibrosis marker was also determined. Creatinine and urea concentrations in blood were measured for the evaluation of renal function. The results demonstrated that renal I/R caused nephrotoxicity, as evidenced by increases in blood urea and creatinine levels, which was reversed by MESNA treatment. Increased free radical levels, as assessed by nitroblue-tetrazolium test were reduced with MESNA. Moreover, the decrease in GSH and increases in MDA levels, and MPO activity induced by I/R indicated that renal injury involves free radical formation. Treatment of rats with MESNA restored the reduced GSH levels while it decreased MDA levels as well as MPO activity. Increased collagen contents of the kidney tissues by I/R were reversed back to the control levels by MESNA treatment. Since MESNA administration reversed these oxidant responses, improved renal function and microscopic damage, it seems likely that MESNA protects kidney tissue against I/R induced oxidative damage.

Topics: Animals; Collagen; Creatinine; Free Radicals; Glutathione; Kidney; Kidney Function Tests; Male; Malondialdehyde; Mesna; Nitroblue Tetrazolium; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Female mice are much more resistant to ischemia/reperfusion (I/R)-induced kidney injury when compared with males. Although estrogen administration can partially reduce kidney injury associated with I/R, we demonstrated that the presence of testosterone, more than the absence of estrogen, plays a critical role in gender differences in susceptibility of the kidney to ischemic injury. Testosterone administration to females increases kidney susceptibility to ischemia. Dihydrotestosterone, which can not be aromatized to estrogen, has effects equal to those of testosterone. Castration reduces the I/R-induced kidney injury. In contrast, ovariectomy does not affect kidney injury induced by ischemia in females. Testosterone reduces ischemia-induced activation of nitric oxide synthases (NOSs) and Akt and the ratio of extracellular signal related kinase (ERK) to c-jun N-terminal kinase (JNK) phosphorylation. Pharmacological (Nomega-nitro-L-arginine) or genetic (endothelial NOS or inducible NOS) inhibition of NOSs in females enhances kidney susceptibility to ischemia. Nitric oxide increases Akt phosphorylation and protects Madin-Darby canine kidney epithelial cells from oxidant stress. Antagonists of androgen or estrogen receptors do not affect the gender differences. In conclusion, testosterone inhibits the post-ischemic activation of NOSs and Akt and the ratio of ERK to JNK phosphorylation through non-androgen receptor-medicated mechanisms, leading to increased inflammation and increased functional injury to the kidney. These findings provide a new paradigm for the design of therapies for ischemia/reperfusion injury and may be important to our understanding of the pathophysiology of acute renal failure in pregnancy where plasma androgen levels are elevated.

Topics: Animals; Extracellular Signal-Regulated MAP Kinases; Female; Intercellular Adhesion Molecule-1; Ischemia; JNK Mitogen-Activated Protein Kinases; Kidney; Male; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Knockout; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Pregnancy; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-akt; Reperfusion Injury; Sex Characteristics; Testosterone

The peroxisome proliferator-activated receptor-alpha (PPAR-alpha) is a member of the nuclear receptor superfamily of ligand-dependent transcription factors related to retinoid, steroid, and thyroid hormone receptors. WY 14643 is a potent PPAR-alpha ligand that modulates the transcription of target genes. The aim of this study was to investigate the effect of WY 14643 on the tissue injury caused by ischemia-reperfusion (I/R) of the gut. I/R injury of the intestine was caused by clamping both the superior mesenteric artery and the celiac trunk for 45 min, followed by release of the clamp, allowing reperfusion for 2 h or 4 h. This procedure results in splanchnic artery occlusion (SAO) shock. Rats subjected to SAO developed a significant fall in mean arterial blood pressure, and only 20% of the animals survived for the entire 4-h reperfusion period. Surviving animals were sacrificed for histological examination and biochemical studies. Rats subjected to SAO displayed a significant increase in tissue myeloperoxidase (MPO) activity, significant increases in plasma tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta levels, and marked injury to the distal ileum. Increased immunoreactivity to nitrotyrosine and polyadenosine diphosphate [ADP]-ribose (PAR) was observed in the ileum of rats subjected to SAO. Staining of sections of the ileum obtained from SAO rats with anti-intercellular adhesion molecule (ICAM-1) antibody or with anti-P-selectin antibody resulted in diffuse staining. Administration of WY 14643 (1 mg/kg i.v.) 30 min before the onset of gut ischemia significantly reduced the (a) fall in mean arterial blood pressure, (b) mortality rate, (c) infiltration of the reperfused intestine with polymorphonuclear neutrophils (MPO activity), (d) production of proinflammatory cytokines (TNF-alpha and IL-1beta), and (e) histological evidence of gut injury. Administration of WY 14643 also markedly reduced the nitrotyrosine formation, poly(adenosine diphosphate [ADP]-ribose) polymerase (PARP) activation, up-regulation of ICAM-1, and expression of P-selectin during reperfusion. These results demonstrate that the PPAR-alpha agonist WY 14643 significantly reduces I/R injury of the intestine.

Topics: Animals; Blood Pressure; Ileum; Immunohistochemistry; Intercellular Adhesion Molecule-1; Interleukin-1; Male; Neutrophils; P-Selectin; Peroxidase; Peroxisome Proliferators; Poly(ADP-ribose) Polymerases; Pyrimidines; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Shock; Splanchnic Circulation; Tumor Necrosis Factor-alpha; Tyrosine; Up-Regulation

To study the protective effects of tumor necrosis factor alpha (TNF alpha) antibody and ulinastatin on liver ischemic reperfusion in rats.. One hundred and twenty male SD rats were randomly divided into four groups: normal control group, ischemic group, TNF alpha antibody group and TNF alpha antibody + ulinastatin group. The animals were killed at 0, 3, 6, 9, 12 h after ischemia for 60 min and followed by reperfusion. Serum alanine aminotransferase (ALT), malondialdehyde (MDA) and liver histopathology were observed.. After ischemic reperfusion, the serum ALT and MDA were remarkably increased, and the hepatic congestion was obvious. Treatment of TNF alpha antibody and ulinastatin could significantly decrease serum ALT and MDA levels, and relieve hepatic congestion.. Ulinastatin and TNF alpha antibody can suppress the inflammatory reaction induced by hepatic ischemic reperfusion, and have protective effects on rat hepatic ischemic reperfusion injury.

Topics: Alanine Transaminase; Animals; Antibodies; Glycoproteins; Liver; Male; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Trypsin Inhibitors; Tumor Necrosis Factor-alpha

Caspase activation has been implicated in the development of ischemia-reperfusion injury. Here, we investigate the effects of different caspase inhibitors on the renal dysfunction and injury caused by ischemia-reperfusion of the rat kidney. Bilateral clamping of renal pedicles (45 min) followed by reperfusion (6 h) caused significant renal dysfunction and marked renal injury. Caspase-1 inhibitor II (N-acetyl-L-tyrosyl-L-valyl-N-[(1S)-1-(carboxymethyl)-3-chloro-2-oxo-propyl]-L-alaninamide, Ac-YVAD-CMK, 3 mg/kg, administered i.p.) significantly reduced biochemical and histological evidence of renal dysfunction and injury. However, although caspase-3 inhibitor I (N-acetyl-L-aspartyl-L-glutamyl-N-(2-carboxyl-1-formylethyl]-L-valinamide, Ac-DEVD-CHO, 3 mg/kg, administered i.p.) produced a significant improvement of renal (glomerular) dysfunction (reduction of serum creatinine levels), it was not able to reduce tubular dysfunction and injury. Furthermore, the pan-caspase inhibitor caspase inhibitor III (N-tert-butoxycarbonyl-aspartyl(OMe)-fluoromethylketone, Boc-D-FMK, 3 mg/kg, administered i.p.) did not reduce renal dysfunction and injury. Both caspase-1 and -3 inhibitors markedly reduced the evidence of oxidative and nitrosative stress in rat kidneys subjected to ischemia-reperfusion. Overall, these results demonstrate that inhibition of caspase-1 reduces renal ischemia-reperfusion injury to a greater extent than caspase-3 inhibition, supporting the notion that the mode of acute cell death in our model of renal ischemia-reperfusion is primarily via necrosis. Furthermore, our finding that a pan-caspase inhibitor did not reduce the renal dysfunction and injury suggests that activation of some caspases during ischemia-reperfusion could provide protection against acute ischemic renal injury. Overall, these results demonstrate that inhibition of caspase-1 activity reduces renal ischemia-reperfusion injury and that this therapeutic strategy may be of benefit against ischemic acute renal failure.

Topics: Animals; Benzyl Compounds; Biomarkers; Caspase 3; Caspase Inhibitors; Cysteine Proteinase Inhibitors; Hydrocarbons, Fluorinated; Immunohistochemistry; In Vitro Techniques; Intercellular Adhesion Molecule-1; Kidney; Kidney Function Tests; Male; Malondialdehyde; Myocardium; Nitric Oxide; Oligopeptides; Organ Size; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Serpins; Tyrosine; Viral Proteins

Ischemia-reperfusion (I/R) is an important cause of acute renal failure (ARF). The complement system appears to be essentially involved in I/R injury. However, via which pathway the complement system is activated and in particular whether the mannose-binding lectin (MBL)-pathway is activated is unclear. This tempted us to study the activation and regulation of the MBL-pathway in the course of experimental renal I/R injury and in clinical post-transplant ARF. Mice subjected to renal I/R displayed evident renal MBL-depositions, depending on the duration of warm ischemia, in the early reperfusion phase. Renal deposition of C3, C6 and C9 was observed in the later reperfusion phase. The deposition of MBL-A and -C completely co-localized with the late complement factor C6, showing that MBL is involved in complement activation in the course of renal I/R injury. Moreover, the degree of early MBL-deposition correlated with complement activation, neutrophil-influx, and organ-failure observed in the later reperfusion phase. In serum of mice subjected to renal I/R MBL-A, levels increased in contrast to MBL-C levels, which dropped evidently. In line, liver mRNA levels for MBL-A increased, whereas MBL-C levels decreased. Renal MBL mRNA levels rapidly dropped in the course of renal I/R. Finally, in human biopsies, MBL-depositions were observed early after transplantation of ischemically injured kidneys. In line with our experimental data, in ischemically injured grafts displaying post-transplant organ-failure extensive MBL depositions were observed in peritubular capillaries and tubular epithelial cells. In conclusion, in experimental renal I/R injury and clinical post-transplant ARF the MBL-pathway is activated, followed by activation of the complement system. These data indicate that the MBL-pathway is involved in ischemia-induced complement activation.

Topics: Animals; Antibodies, Monoclonal; Biopsy; Complement Activation; Enzyme-Linked Immunosorbent Assay; Humans; Immunohistochemistry; Kidney; Lectins; Liver; Lung; Male; Mannose; Mannose-Binding Lectin; Mice; Neutrophils; Peroxidase; Protein Binding; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Time Factors

The cellular and molecular events involved in ischaemia reperfusion (IR) injury are complex and not fully understood. Previous studies have implicated polymorphonuclear neutrophils (PMN) as major inflammatory cells in IR injury. However, anti-PMN antiserum treatment offers only limited protection, indicating that other inflammatory cells are involved. We have therefore investigated the contribution of resident macrophages in IR injury using an IR gut injury model.. DA rats were divided into sham operation and IR groups. The superior mesenteric artery was clamped for 30, 45, or 60 minutes (ischaemia) followed by 60 minutes of reperfusion. IR injuries were evaluated by histological staining. Expression of early growth response factor 1 (Egr-1), myeloperoxidase (MPO), and proinflammatory cytokines was analysed by immunohistochemistry, reverse transcription-polymerase chain reaction, and western blotting analysis. The specific role of macrophages in IR gut injury was also evaluated in resident macrophage depleted rats.. Mucosal sloughing and villi destruction were seen in 45/60 minute and 60/60 minute IR guts. PMN infiltration at the damaged mucosal area was undetectable in 45/60 minute and 60/60 minute IR guts. PMN were localised around the capillaries at the base of the crypts in 60/60 minute IR gut. Obvious PMN infiltration was only observed in damaged villi after three hours of reperfusion. Elevated nuclear Egr-1 immunostaining was localised in resident macrophages at the damaged villi before histological appearance of mucosal damage. Furthermore, resident macrophages at the damaged site expressed MPO. Protein levels of the proinflammatory cytokines RANTES and MCP-1 were increased in IR gut. Depletion of resident macrophages by dichloromethylene bisphosphonate significantly reduced mucosal damage in rat guts after IR.. Our findings indicate that resident macrophages play a role in early mucosal damage in IR gut injury. Therefore, macrophages should be treated as a prime target for therapeutic intervention for IR damage.

Topics: Animals; Cytokines; DNA-Binding Proteins; Early Growth Response Protein 1; Gene Expression; Immediate-Early Proteins; Intestinal Mucosa; Jejunum; Macrophages; Neutrophils; Peroxidase; Rats; Reperfusion Injury; RNA, Messenger; Transcription Factors

Peroxisome proliferator-activated receptor gamma (PPAR-gamma) is a nuclear hormone receptor super family that has recently been implicated in atherosclerosis, inflammation, cancer, infertility, and demyelination. Oxidative stress, neutrophil infiltration, proinflammatory cytokines, and the exhibition of luminal acid play a role in the pathogenesis of gastric injury induced by ischemia-reperfusion. Rosiglitazone, a specific PPAR-gamma ligand, has been shown to have antiinflammatory activity, but its effects on experimental ischemia-reperfusion gastric injury remain unknown. We have investigated the effects of the rosiglitazone on gastric injury caused by ischemia following reperfusion in rats. Tumour necrosis factor-alpha (TNF-alpha) levels and changes in enzymatic activities of myeloperoxidase, as a marker of neutrophils infiltration, xanthine oxidase, superoxide dismutase, and glutathione peroxidase, were determined. Histological analysis of the lesions was also carried out. Pretreatment with 1 or 4 mg/kg of rosiglitazone ameliorated the gastric damage induced by clamping the celiac artery for 30 min followed by 60 min of reperfusion. It significantly (P<0.05) reduced the index of neutrophil infiltration and the levels of the cytokine. Rosiglitazone did not revert the reduced glutathione peroxidase activity but enhanced significantly (P<0.01) the decreased xanthine oxidase and superoxide dismutase activities in gastric mucosa of ischemic rats. In conclusion, rosiglitazone reduces the damage in ischemia-reperfusion gastric injury and alleviates the inflammatory response and the oxidative events.

Topics: Animals; Cyclooxygenase 1; Cyclooxygenase 2; Gastric Mucosa; Glutathione Peroxidase; Immunohistochemistry; Male; Membrane Proteins; Necrosis; Neutrophils; Oxidative Stress; Peroxidase; PPAR gamma; Prostaglandin-Endoperoxide Synthases; Rats; Rats, Wistar; Reactive Oxygen Species; Reperfusion Injury; Rosiglitazone; Stomach; Superoxide Dismutase; Thiazolidinediones; Tumor Necrosis Factor-alpha; Up-Regulation; Xanthine Oxidase

We evaluated the effects of Y-27632 [(+)-(R)-trans-4-(1-aminoethyl)-N-(4-pyridyl) cyclohexanecarboxamide dihydrochloride monohydrate], a selective Rho-kinase inhibitor, on ischemic acute renal failure. Ischemic acute renal failure in rats was induced by clamping the left renal artery and vein for 45 min followed by reperfusion, 2 weeks after the contralateral nephrectomy. Y-27632 administration (1, 10, and 100 microg/kg, i.p.) before ischemia dose-dependently attenuated the ischemia/reperfusion-induced renal dysfunction and histological damage, such as tubular necrosis. The ischemia/reperfusion-induced renal dysfunction was also overcome by postischemic treatment with Y-27632 at 100 microg/kg, i.p. Myeloperoxidase activity in the kidney after ischemia/reperfusion was significantly increased, being the maximal level at 6 h after the reperfusion, and this increase was also suppressed by Y-27632 (100 microg/kg, i.p.). These results indicate that Y-27632 prevents the development of ischemia/reperfusion-induced acute renal failure, and the effect is related to the suppression of the enhanced myeloperoxidase activity in an early phase after reperfusion, thereby suggesting that the Rho/Rho-kinase pathway plays a key role in the pathogenesis of ischemic acute renal failure.

Topics: Acute Kidney Injury; Amides; Animals; Enzyme Inhibitors; Intracellular Signaling Peptides and Proteins; Kidney; Kidney Function Tests; Male; Peroxidase; Protein Serine-Threonine Kinases; Pyridines; Rats; Rats, Sprague-Dawley; Reperfusion Injury; rho-Associated Kinases; Time Factors

To study the protective effects of phenolic alkaloids from Menispermum dauricum (PAMd) on inflammatory injury following focal cerebral ischemia-reperfusion in rats.. The right middle cerebral artery of the rat was occluded by inserting a nylon suture through the internal carotid artery for 2 h, followed by reperfusion by withdrawing the suture. The expression of intercellular adhesion molecule-1 (ICAM-1) was observed by immunohistochemistry staining. The adhesiveness and infiltration of leucocytes were observed by HE staining. The activity of myeloperoxidase (MPO) and the content of nitric oxide (NO) in the cortex and hippocampus were measured.. PAMd was shown to markedly inhibit ICAM-1 expression, alleviate the adhesiveness and infiltration of leucocytes, and decrease the MPO activity and the NO content in ischemic cortex and hippocampus.. PAMd has protective effects on inflammatory injury following focal cerebral ischemia-reperfusion by inhibiting ICAM-1 expression, alleviating the adhesiveness and infiltration of leucocytes and decreasing the generation of NO.

Topics: Alkaloids; Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzylisoquinolines; Brain Ischemia; Cell Adhesion; Cerebral Cortex; Female; Hippocampus; Intercellular Adhesion Molecule-1; Leukocytes; Male; Menispermum; Neuroprotective Agents; Neutrophil Infiltration; Nitric Oxide; Peroxidase; Plants, Medicinal; Rats; Rats, Wistar; Reperfusion Injury; Tetrahydroisoquinolines

Volatile anesthetics protect against cardiac ischemia-reperfusion injury via adenosine triphosphate-dependent potassium channel activation. The authors questioned whether volatile anesthetics can also protect against renal ischemia-reperfusion injury and, if so, whether cellular adenosine triphosphate-dependent potassium channels, antiinflammatory effects of volatile anesthetics, or both are involved.. Rats were anesthetized with equipotent doses of volatile anesthetics (desflurane, halothane, isoflurane, or sevoflurane) or injectable anesthetics (pentobarbital or ketamine) and subjected to 45 min of renal ischemia and 3 h of reperfusion during anesthesia.. Rats treated with volatile anesthetics had lower plasma creatinine and reduced renal necrosis 24-72 h after injury compared with rats anesthetized with pentobarbital or ketamine. Twenty-four hours after injury, sevoflurane-, isoflurane-, or halothane-treated rats had creatinine (+/- SD) of 2.3 +/- 0.7 mg/dl (n = 12), 1.8 +/- 0.5 mg/dl (n = 6), and 2.4 +/- 1.2 mg/dl (n = 6), respectively, compared with rats treated with pentobarbital (5.8 +/- 1.2 mg/dl, n = 9) or ketamine (4.6 +/- 1.2 mg/dl, n = 8). Among the volatile anesthetics, desflurane demonstrated the least reduction in plasma creatinine after 24 h (4.1 +/- 0.8 mg/dl, n = 12). Renal cortices from volatile anesthetic-treated rats demonstrated reduced expression of intercellular adhesion molecule 1 protein and messenger RNA as well as messenger RNAs encoding proinflammatory cytokines and chemokines. Volatile anesthetic treatment reduced renal cortex myeloperoxidase activity and reduced nuclear translocation of proinflammatory nuclear factor kappaB. Adenosine triphosphate-dependent potassium channels are not involved in sevoflurane-mediated renal protection because glibenclamide did not block renal protection (creatinine: 2.4 +/- 0.4 mg/dl, n = 3).. Some volatile anesthetics confer profound protection against renal ischemia-reperfusion injury compared with pentobarbital or ketamine anesthesia by attenuating inflammation. These findings may have significant clinical implications for anesthesiologists regarding the choice of volatile anesthetic agents in patients subjected to perioperative renal ischemia.

Topics: Anesthetics, Inhalation; Animals; ATP-Binding Cassette Transporters; Creatinine; Cytokines; Electrophoretic Mobility Shift Assay; Immunoblotting; Inflammation; Inflammation Mediators; Intercellular Adhesion Molecule-1; Ischemia; KATP Channels; Kidney; Kidney Cortex; Kidney Diseases; Kidney Function Tests; Male; Necrosis; NF-kappa B; Peroxidase; Potassium Channels; Potassium Channels, Inwardly Rectifying; Proteins; Rats; Rats, Sprague-Dawley; Renal Circulation; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; Tumor Necrosis Factor-alpha

The aim of this experimental study was to investigate whether nebivolol has protective effects against neuronal damage induced by spinal cord ischemia/reperfusion (I/R). Twenty-one rabbits were divided into three groups: group I (control, no I/R), group II (only I/R) and group III (I/R+nebivolol). Spinal cord ischemia was induced by clamping the aorta both below the left renal artery and above the aortic bifurcation. Seventy-two hours postoperatively, the motor function of the lower limbs was evaluated in each animal. The animals were sacrificed at 72 h, and histopathological and biochemical analyses were carried out in the lumbar spinal cords. The motor deficit scores in nebivolol group were different from I/R group at 72 h (3.25+/-0.70 vs. 1.75+/-1.28, p=0.01). I/R produced a significant increase in the superoxide dismutase (SOD), xanthine oxidase (XO), adenosine deaminase (ADA) and myeloperoxidase (MPO) activities in spinal cord tissue when compared with control group. Nebivolol treatment prevented the increase of all those enzymes activities produced by I/R. A significant decrease in spinal cord glutathione peroxidase (GSH-Px) level was seen in I/R group and nebivolol treatment prevented the decrement in the spinal cord tissue GSH-Px contents. On the other hand, I/R produced a significant increase in the spinal cord tissue malondialdehyde (MDA) and nitric oxide (NO) contents, this was prevented by nebivolol treatment. In conclusion, this study demonstrates a considerable neuroprotective effect of nebivolol on neurological, biochemical and histopathological status during periods of spinal cord I/R in rabbits.

Topics: Adenosine Deaminase; Adrenergic beta-Antagonists; Animals; Benzopyrans; Ethanolamines; Free Radicals; Glutathione Peroxidase; Malondialdehyde; Nebivolol; Nerve Tissue Proteins; Neuroprotective Agents; Nitric Oxide; Oxidative Stress; Peroxidase; Rabbits; Reperfusion Injury; Spinal Cord; Spinal Cord Injuries; Superoxide Dismutase; Xanthine Oxidase

In ischemia-reperfusion (I/R)-induced tissue injury, oxygen radicals can be generated by several mechanisms. One of the important sources of oxygen radicals is thought to be mitochondrial respiration. The aim of this study was to investigate the antioxidative defense effect of the mitochondrial electron transport inhibitor, rotenone using the I/R-induced rat intestinal mucosal injury model in vivo. Intestinal ischemia was induced for 30 min by applying a small clamp to the superior mesenteric artery in rats. Rotenone at a dose of 100 mg/kg was given to rats orally 2 h before the ischemia. Intraluminal hemoglobin and protein levels, the mucosal content of thiobarbituric acid-reactive substances (TBARS), the mucosal myeloperoxidase activity, and the content of inflammatory cytokines (CINC-1, TNF-alpha) were all significantly increased from mean basal levels after 60 min of reperfusion. These increases after I/R were inhibited by treatment with rotenone at a dose of 100 mg/kg. Co-administration with succinate (100 mg/kg), a substrate of the mitochondrial electron transport system, cancelled significant reduction of intraluminal hemoglobin and mucosal TBARS treated with rotenone alone. The results of the present study indicate that rotenone inhibited lipid peroxidation and reduced development of the intestinal mucosal inflammation induced by I/R in rats. This investigation suggests that rotenone has potential as a new therapeutic agent for reperfusion injury.

Topics: Animals; Antioxidants; Cytokines; Electron Transport; Hemoglobins; Intestinal Mucosa; Intestine, Small; Lipid Peroxidation; Male; Mitochondria; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Rotenone; Succinates; Thiobarbituric Acid Reactive Substances

Recent studies have demonstrated the anti-inflammatory action of 15-deoxy-Delta12,14-prostaglandin J(2) (15d-PGJ(2)), a derivative of the PGD(2) metabolic pathway. Acute inflammation, including neutrophil activation, plays a critical role in the pathogenesis of ischemia-reperfusion (I/R). The aim of the present study was to determine the effect of 15d-PGJ(2) on I/R-induced gastric mucosal injury in rats.. Gastric mucosal damage was induced in male Wistar rats by clamping the celiac artery for 30 min followed by reperfusion. 15d-PGJ(2) (0.01-1.0 mg/kg) was given to the rats intraperitoneally 1 h before the vascular clamping. The area of gastric mucosal erosions (erosion index) was measured. Thiobarbituric acid reactive substances (TBARS) and tissue-associated myeloperoxidase (MPO) activity were measured in the gastric mucosa as indices of lipid peroxidation and neutrophil infiltration. The expression of tumor necrosis factor-alpha (TNF-alpha) in gastric mucosa was measured by ELISA. In addition, to elucidate whether the protective effects of 15d-PGJ(2) are related to the activation of the PPAR-gamma receptor, we also investigated the effects of a PPAR-gamma antagonist, GW9662.. After 60 min of reperfusion, the area of gastric erosion index had significantly increased from the mean basal levels. The increase in the erosion index was significantly inhibited by pretreatment with 15d-PGJ(2) in a dose-dependent manner. On the other hand, GW9662 reversed the protective effect of 15d-PGJ(2). The concentration of TBARS and MPO activity in the gastric mucosa were both significantly increased after I/R, and pretreatment with 15d-PGJ(2) significantly reduced these increases. The TNF-alpha content was significantly higher in the I/R group than in the sham-operated group. However, the increase in TNF-alpha was significantly inhibited by pretreatment with 15d-PGJ(2).. 15d-PGJ(2) significantly inhibited the severity of acute gastric mucosal injury induced by I/R in rats through PPAR-gamma-dependent mechanisms. This effect may be due, in part, to a reduction in the infiltration of neutrophils into the gastric mucosa, possibly via the inhibition of inflammatory cytokine.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Gastric Mucosa; Male; Peroxidase; PPAR gamma; Prostaglandin D2; Rats; Rats, Wistar; Reperfusion Injury; Thiobarbituric Acid Reactive Substances; Tumor Necrosis Factor-alpha

The objective of this study is to investigate the anti-inflammatory effect of hydroxyethylpuerarin on focal brain ischemia injury in rats and to explore its mechanisms of action. After 24 h of reperfusion following 2 h of cerebral ischemia, the infiltration of neutrophils was observed by myeloperoxidase (MPO) activity determination, the expression of intercellular adhesion molecule-1 (ICAM-1) was observed by western blot and reverse transcriptase-polymerase chain reaction (RT-PCR) analysis, and the nuclear translocation and DNA binding activity of nuclear factor-kappaB (NF-kappaB) were observed by western blot and electrophoretic mobility shift assay (EMSA). The results showed that hydroxyethylpuerarin could obviously inhibit the MPO activity and ICAM-1 expression following 2 hours of ischemia with 24 hours of reperfusion. The nuclear translocation and DNA binding activity were also decreased by hydroxyethylpuerarin treatment. These results suggested that hydroxyethylpuerarin could inhibit neutrophil-mediated inflammatory response after brain ischemia reperfusion in rats. This effect may be mediated by down-regulation of ICAM-1 and NF-kappaB activity.

Topics: Animals; Anti-Inflammatory Agents; Blotting, Western; Brain; Brain Chemistry; Brain Ischemia; Cell Nucleus; Cytoplasm; DNA; Electrophoretic Mobility Shift Assay; Intercellular Adhesion Molecule-1; Isoflavones; Male; Neuroprotective Agents; NF-kappa B; Oncogene Protein p65(gag-jun); Peroxidase; Rats; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction

Mesenteric ischemia-reperfusion injury is a serious complication of shock. Because activation of nuclear factor-kappaB (NF-kappaB) has been implicated in this process, we treated rats with vehicle or the IkappaB-alpha inhibitor BAY 11-7085 (25 mg/kg ip) 1 h before mesenteric ischemia-reperfusion (45 min of ischemia followed by reperfusion at 30 min or 6 h) and examined the ileal injury response. Vehicle-treated rats subjected to ischemia-reperfusion exhibited severe mucosal injury, increased myeloperoxidase (MPO) activity, increased expression of interleukin-6 and intercellular adhesion molecule 1 protein, and a biphasic peak of NF-kappaB DNA-binding activity during the 30-min and 6-h reperfusion courses. In contrast, BAY 11-7085-pretreated rats subjected to ischemia-reperfusion exhibited less histological injury and less interleukin-6 and intercellular adhesion molecule 1 protein expression at 30 min of reperfusion but more histological injury at 6 h of reperfusion than vehicle-treated rats subjected to ischemia-reperfusion. Studies with phosphorylation site-specific antibodies demonstrated that IkappaB-alpha phosphorylation at Ser(32),Ser(36) was induced at 30 min of reperfusion, whereas tyrosine phosphorylation of IkappaB-alpha was induced at 6 h of reperfusion. BAY 11-7085 inhibited the former, but not the latter, phosphorylation pathway, whereas alpha-melanocyte-stimulating hormone, which is effective in limiting late ischemia-reperfusion injury to the intestine, inhibited tyrosine phosphorylation of IkappaB-alpha. Thus NF-kappaB appears to play an important role in the generation and resolution of intestinal ischemia-reperfusion injury through different activation pathways.

Topics: alpha-MSH; Animals; Anti-Infective Agents; I-kappa B Proteins; Ileum; Intercellular Adhesion Molecule-1; Interleukin-6; Male; NF-kappa B; NF-KappaB Inhibitor alpha; Nitriles; Peroxidase; Phosphorylation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Splanchnic Circulation; Sulfones

C5a has been implicated in numerous pathophysiological conditions, including ischemia/reperfusion (I/R) injury of the kidney. We examined whether a novel and specific C5a receptor antagonist, the cyclic compound AcF-[OPdChaWR] could moderate I/R-induced renal injury in rats.. Female Wistar rats were subjected to renal ischemia (60 min) and reperfusion (5 h). Rats were treated with either 1 mg/kg IV in 5% ethanol/saline or 10 mg/kg PO in 25% ethanol/saline prior to ischemia. I/R injury was characterized by significant tissue hemorrhage with increased microvascular permeability, elevated renal tissue levels of tumor necrosis factor-alpha (TNF-alpha) and myeloperoxidase (MPO), increased serum levels of creatinine and aspartate aminotransferase (AST) and hematuria.. Pre-ischemic treatment with the C5a receptor (C5aR) antagonist (1 mg/kg IV or 10 mg/kg PO) substantially inhibited or prevented I/R-induced hematuria, vascular leakage, tissue levels of TNF-alpha and MPO, and serum levels of AST and creatinine. Histological examination of kidneys from antagonist pretreated I/R animals showed a marked reduction in tissue damage compared to drug-free I/R rats. This antagonist, however, did not inhibit complement-mediated lysis of red blood cells, suggesting unimpaired formation of the membrane attack complex (MAC).. The results demonstrate for the first time that a selective antagonist of both human and rat C5a receptors, given either intravenously or orally, significantly protects the kidney from I/R injury in the rat. We conclude that C5a is an important pathogenic agent in renal I/R injury, and that C5a receptor antagonists may be useful therapeutic agents for the pretreatment of anticipated renal reperfusion injury in humans.

Topics: Animals; Aspartate Aminotransferases; Biomarkers; Complement Membrane Attack Complex; Creatinine; Disease Models, Animal; Female; Kidney; Kidney Diseases; Leukocyte Count; Leukocytes; Microcirculation; Peptides, Cyclic; Peroxidase; Rats; Rats, Wistar; Receptor, Anaphylatoxin C5a; Renal Circulation; Reperfusion Injury; Tumor Necrosis Factor-alpha; Urine

Antithrombin (AT) supplementation in patients with severe sepsis has been shown to improve organ failures in which activated leukocytes are critically involved. However, the precise mechanism(s) for the therapeutic effects of AT is not well understood. We examined in rats whether AT reduces ischemia/reperfusion (I/R)-induced renal injury by inhibiting leukocyte activation. AT markedly reduced the I/R-induced renal dysfunction and histologic changes, whereas neither dansyl glutamylglycylarginyl chloromethyl ketone-treated factor Xa (DEGR-F.Xa), a selective inhibitor of thrombin generation, nor Trp49-modified AT, which lacks affinity for heparin, had any effect. Renal tissue levels of 6-keto-PGF(1 alpha), a stable metabolite of prostacyclin (PGI(2)), increased after renal I/R. AT enhanced the I/R-induced increases in renal tissue levels of 6-keto-PGF(1 alpha), whereas neither DEGR-F.Xa nor Trp49-modified AT had any effect. AT significantly inhibited I/R-induced decrease in renal tissue blood flow and the increase in the vascular permeability. Ischemia/reperfusion-induced increases in renal tissue levels of tumor necrosis factor-alpha, cytokine-induced neutrophil chemoattractant, and myeloperoxidase were significantly inhibited in animals given AT. Pretreatment of animals with indomethacin reversed the effects induced by AT. Iloprost, an analog of PGI(2), produced effects similar to those induced by AT. These observations strongly suggest that AT reduces the I/R-induced renal injury by inhibiting leukocyte activation. The therapeutic effects of AT might be mainly mediated by PGI(2) released from endothelial cells through interaction of AT with cell surface glycosaminoglycans.

Topics: 6-Ketoprostaglandin F1 alpha; Amino Acid Chloromethyl Ketones; Animals; Anti-Inflammatory Agents, Non-Steroidal; Antithrombin III; Capillary Permeability; Drug Evaluation, Preclinical; Endothelium, Vascular; Epoprostenol; Factor Xa; Iloprost; Indomethacin; Ischemia; Kidney; Lymphocyte Activation; Male; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Specific Pathogen-Free Organisms; Tumor Necrosis Factor-alpha

Inhibition of neutrophil-endothelial cell interactions by hypertonic saline (HTS) may confer protection against organ injury in states of immunologic disarray. This study tested the hypothesis that infusion of HTS modulates the development of end-organ injury in a model of lower-torso ischemia-reperfusion injury.. Ischemia-reperfusion injury was induced in 30 male Sprague-Dawley rats by infrarenal aortic cross-clamp for 30 minutes, followed by reperfusion for 2 hours. At 0 and 60 minutes of reperfusion, intravenous HTS (7.5% sodium chloride, 4 mL/kg) was administered to 6 rats each, and another 12 received either 4 or 30 mL/kg of isotonic sodium chloride solution. Six rats received HTS, 4 mL/kg, before ischemia. At 2 hours, we assessed liver function, pulmonary injury, neutrophil infiltration (myeloperoxidase activity), endothelial permeability (bronchoalveolar lavage and wet-dry weight ratios), and proinflammatory cytokine levels (tumor necrosis factor alpha and interleukin 6).. Infusion with HTS before or after ischemia significantly reduced end-organ injury. Histopathologic pulmonary injury scores were markedly attenuated in the HTS group (5.82 +/- 1.3) and the HTS pretreated group (4.91 +/- 1.6) compared with the isotonic sodium chloride solution groups (8.54 +/- 1.1) (P =.04). Pulmonary neutrophil sequestration (2.07 +/- 0.23) and increased endothelial permeability (4.68 +/- 0.44) were manifest in animals resuscitated with isotonic sodium chloride solution compared with HTS treatment (1.54 +/- 0.19 [P =.04] and 2.06 +/- 0.26 [P =.02]) and pretreatment (1.18 +/- 0.12 [P =.04] and 1.25 +/- 0.07 [P =.002]). In addition, a significant reduction in serum tumor necrosis factor alpha (P =.04) and interleukin 6 (P =.048) levels was observed, whereas HTS resuscitation attenuated the upsurge in aspartate transaminase (P =.03) and alanine transaminase levels (P =.047).. Resuscitation with HTS attenuates the pulmonary edema and tissue injury due to lower-torso ischemia-reperfusion and maintains a more benign immunologic profile.

Topics: Animals; Aorta, Thoracic; Cell Communication; Constriction; Endothelium; Infusions, Intravenous; Interleukin-6; Liver; Lung Diseases; Male; Models, Animal; Permeability; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Saline Solution, Hypertonic; Tumor Necrosis Factor-alpha

The complement system is thought to play a major role in initiating some of the inflammatory events that occur during reperfusion injury. The aim of this study was to assess the effects of C1 esterase inhibitor (C1-INH) on ischemic injury in the rat model of middle cerebral artery suture occlusion and reperfusion.. Thirty-six male Wistar rats were used. Intraluminal middle cerebral artery occlusion was performed for 60 minutes. Just before reperfusion, C1-INH (50 international units/kg) (C1-INH group, n = 19) or saline solution (control group, n = 17) was administered. Physiological parameters (arterial blood gas values, mean arterial blood pressure, and heart rate) and local cerebral blood flow were recorded during the experiment. Forty-eight hours after reperfusion, all rats were killed, and assessments of leukocyte infiltration with a myeloperoxidase activity assay and histological analyses with 2,3,5-triphenyl tetrazolium chloride staining were performed.. The physiological parameters and local cerebral blood flow values were not significantly different in the two groups. The infarction volume was significantly smaller and the myeloperoxidase activity was significantly lower in the C1-INH group (84.9 +/- 69.1 mm(3) and 0.40 +/- 0.29 units/g, respectively) than in the control group (202.3 +/- 98.3 mm(3) and 1.41 +/- 0.44 units/g, respectively) (P < 0.01). Myeloperoxidase activities were strongly correlated with infarction volumes (r = 0.73, P < 0.01).. The results of this study indicated that C1-INH reduced polymorphonuclear leukocyte accumulation and neuronal damage in focal ischemia and reperfusion.

Topics: Animals; Brain; Complement C1 Inactivator Proteins; Infarction, Middle Cerebral Artery; Leukocyte Count; Male; Neurons; Peroxidase; Rats; Rats, Wistar; Regional Blood Flow; Reperfusion Injury

The terminal complement components play an important role in mediating tissue injury after ischemia and reperfusion (I/R) injury in rats and mice. However, the specific complement pathways involved in I/R injury are unknown. The role of the alternative pathway in I/R injury may be particularly important, as it amplifies complement activation and deposition. In this study, the role of the alternative pathway in I/R injury was evaluated using factor D-deficient (-/-) and heterozygote (+/-) mice. Gastrointestinal ischemia (GI) was induced by clamping the mesenteric artery for 20 minutes and then reperfused for 3 hours. Sham-operated control mice (+/- versus -/-) had similar baseline intestinal lactate dehydrogenase activity (P = ns). Intestinal lactate dehydrogenase activity was greater in -/- mice compared to +/- mice after GI/R (P = 0.02) thus demonstrating protection in the -/- mice. Intestinal myeloperoxidase activity in +/- mice was significantly greater than -/- mice after GI/R (P < 0.001). Pulmonary myeloperoxidase activity after GI/R was significantly higher in +/- than -/- mice (P = 0.03). Addition of human factor D to -/- animals restored GI/R injury and was prevented by a functionally inhibitory antibody against human factor D. These data suggest that the alternative complement pathway plays an important role in local and remote tissue injury after GI/R. Inhibition of factor D may represent an effective therapeutic approach for GI/R injury.

Topics: Animals; Complement Factor D; Complement Pathway, Alternative; Kinetics; L-Lactate Dehydrogenase; Mice; Mice, Knockout; Peroxidase; Rats; Reperfusion Injury

Acute inflammatory reactions cause neuronal damage in cerebral ischemia-reperfusion. Urinary trypsin inhibitor (UTI), a serine protease inhibitor, is cytoprotective against ischemia-reperfusion injury in the liver, intestine, kidney, heart, and lung through its antiinflammatory activity. Neuroprotective action of UTI on transient global cerebral ischemia has been documented. This is the first study to determine whether UTI is neuroprotective against transient focal cerebral ischemia.. Adult male Wistar rats were randomly assigned to the following treatment groups: 0.9% saline (control, n = 9); 100,000 U/kg UTI (n = 9); and 300,000 U/kg UTI (n = 9). Treatments were performed intravenously 10 min before right middle cerebral artery occlusion for 2 h and subsequent reperfusion. Ninety-six hours after the onset of reperfusion, the motor neurologic deficit and the cerebral infarct size were evaluated. Furthermore, immunohistochemical staining for myeloperoxidase and nitrotyrosine to count infiltrating neutrophils and nitrated cells, respectively, was performed on the brain sections.. Infarct volume in the 300,000 U/kg UTI group was smaller than in the 100,000 U/kg UTI and saline control groups (P < 0.05). Treatment with 300,000 U/kg UTI showed a trend to improve neurologic outcome but did not reach statistical significance (P = 0.0693). The significant decrease in neutrophil infiltration was observed in the ischemic hemisphere treated with 300,000 U/kg UTI compared with saline control (P < 0.05). Nitrotyrosine deposition in the ischemic hemisphere was significantly reduced in the 300,000 U/kg UTI group compared with saline control and 100,000 U/kg UTI groups (P < 0.05).. Intravenous pretreatment with 300,000 U/kg UTI reduces focal ischemia-reperfusion injury in the rat brain, potentially opening a novel therapeutic avenue for the treatment of cerebral ischemia.

Topics: Animals; Behavior, Animal; Brain; Cell Count; Cerebrovascular Circulation; Glycoproteins; Hypoxia-Ischemia, Brain; Immunohistochemistry; Infarction, Middle Cerebral Artery; Laser-Doppler Flowmetry; Male; Nervous System Diseases; Neuroprotective Agents; Neutrophils; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Trypsin Inhibitors; Tyrosine

Proinflammatory cytokines are known to play roles in ischemia-reperfusion injury of the heart, kidney, small bowel, skin, and liver. Little is known about their roles in ischemia-reperfusion injury of the lung. This study was undertaken to define the role of 2 proinflammatory cytokines, tumor necrosis factor alpha and interleukin 1beta, in ischemia-reperfusion injury of the lung.. Left lungs of male rats were rendered ischemic for 90 minutes and reperfused for up to 4 hours. Treated animals received anti-tumor necrosis factor alpha or anti-interleukin 1beta antibody before reperfusion. Increased vascular permeability in the lung was measured by using iodine 125-labeled bovine serum albumin. Neutrophil sequestration in the lung parenchyma was determined on the basis of activity. Bronchoalveolar lavage was performed to measure cell counts. Separate tissue samples were processed for histology, cytokine protein, and messenger RNA content by using Western blotting and the ribonuclease protection assay.. Animals receiving anti-tumor necrosis factor alpha and anti-interleukin 1beta demonstrated reduced injury compared with that seen in positive control animals (vascular permeability of 48.7% and 29.4% lower, respectively; P <.001). Vascular injury was reduced by 71% when antibodies to tumor necrosis factor alpha and interleukin 1beta were administered together. Lung neutrophil accumulation was markedly reduced among animals receiving anti-tumor necrosis factor alpha and anti-interleukin 1beta (myeloperoxidase content of 30.9% and 38.5% lower, respectively; P <.04) and combination blockade afforded even greater protection (52.4% decrease, P <.01). Bronchoalveolar lavage leukocyte content was also reduced by treatment with anti-tumor necrosis factor alpha, anti-interleukin 1beta, and combination treatment. Reductions in permeability, myeloperoxidase, and bronchoalveolar lavage leukocyte content also resulted in a decrease in a histologic injury. Finally, anti-tumor necrosis factor alpha and anti-interleukin 1beta treatment resulted in decreased messenger RNA expression for a number of early response and regulatory cytokines.. Tumor necrosis factor alpha and interleukin 1beta help regulate the development of lung ischemia-reperfusion injury. They appear to promote injury by altering expression of proinflammatory and anti-inflammatory cytokines and influencing tissue neutrophil recruitment.

Topics: Animals; Biopsy; Blotting, Western; Bronchoalveolar Lavage Fluid; Capillary Permeability; Disease Models, Animal; Immunohistochemistry; Inflammation; Interleukin-1; Leukocyte Count; Lung; Male; Neutrophil Infiltration; Peroxidase; Rats; Rats, Long-Evans; Reperfusion Injury; RNA, Messenger; Tumor Necrosis Factor-alpha

Thermal preconditioning has previously been shown to attenuate ischemia-reperfusion induced injuries, possible due to increased expression of heat shock proteins (HSP). The model of thermal preconditioning used, however, was not clinically relevant as preconditioning was to 41 degrees C, leading to cellular damage. Our aim was thus to establish a novel and clinically applicable method of preconditioning.. Twenty-six male Sprague-Dawley rats were split into three groups (nine control, nine ischemia-reperfusion, and eight preconditioned followed by ischemia-reperfusion). To precondition the animals, they were anesthetized and, using a water bath, their core temperature was raised by 1 degrees C for 15 min once a day for five successive days. I/R injury consisted of 30 min of aortic cross-clamping followed by 120 min of reperfusion; control animals had a laparotomy only. Indicators of lung injury were tissue myeloperoxidase, broncho-alveolar lavage protein concentration, and tissue edema. Tissue heat shock protein expression was detected by Western blot analysis.. Lower torso ischemia-reperfusion causes significant lung injury versus control, with raised levels of myeloperoxidase 4.53 iu/g to 7.88 iu/g (P < 0.05), raised B.A.L. protein concentration 419 microg/ml to 684 microg/ml (P < 0.05) and altered wet dry ratio 4.63 to 5.50. Clinically relevant thermal preconditioning attenuates all of these parameters back to control levels: myeloperoxidase 3.87 iu/g (P < 0.05 vs I/R), B.A.L. to 284 microg/ml (P < 0.01 vs I/R) and wet dry ratio to 4.44 (P < 0.05 vs I/R). Western blot demonstrated increased expression of H.S.P. 72 in the preconditioned group versus control and I/R alone. Western blot demonstrated increased expression of HSP72 in the preconditioned group vs control and I/R alone.. We conclude that clinically applicable thermal preconditioning can attenuate ischemia-reperfusion induced lung injury, possibly through increased expression of HSP72.

Topics: Animals; Aorta; Blotting, Western; Body Temperature; Bronchoalveolar Lavage Fluid; Capillary Permeability; Constriction; Edema; Heat-Shock Proteins; Hot Temperature; HSP72 Heat-Shock Proteins; Ischemic Preconditioning; Lung; Male; Organ Size; Peroxidase; Proteins; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Secondary organ damage to the lungs is an important consequence of intestinal ischaemia reperfusion (IIR) injury. Moderate hypothermia ameliorates gut necrosis and liver energy failure after IIR but potential beneficial effects on lung neutrophil infiltration after reperfusion of ischaemic bowel have not been investigated.. Adult Sprague-Dawley rats underwent 60 minutes intestinal ischaemia followed by 120 minutes of reperfusion. The animals were maintained at either normothermia (36 degrees to 38 degrees C) or moderate hypothermia (30 degrees to 32 degrees C). Four groups were studied: (A) sham normothermia; (B) IIR normothermia; (C) sham hypothermia; and (D) IIR hypothermia. Lungs and terminal ileum were removed for measurement of myeloperoxidase activity (a marker of neutrophil infiltration). Results are expressed as milliunits per milligrams protein, mean +/- SEM, and one-way analysis of variance (ANOVA) with Tukey post-test was used for group comparisons.. Lungs: IIR at normothermia significantly increased lung neutrophil infiltration assessed by myeloperoxidase activity compared with sham-operated controls (normothermia sham 4.6 +/- 1.0, n = 8; normothermia IIR 37.7 +/- 13.8, n = 8; P =.011). Moderate hypothermia during IIR significantly attenuated lung neutrophil infiltration (7.2 +/- 2.1, n = 9) compared with normothermia IIR (P =.016) such that myeloperoxidase activity was similar to that found in sham normothermia (4.6 +/- 1.0, n = 8) and sham hypothermia (3.1 +/- 1.3, n = 8). Intestine: Gut myeloperoxidase activity was 0.9 +/- 0.5 in sham normothermia (n = 9) and 2.3 +/- 0.6 after normothermic IIR (n = 8). After IIR at hypothermia gut myeloperoxidase activity (0.5 +/- 0.2; n = 8) was significantly less than normothermic IIR (P =.035) and higher than sham hypothermia (0.2 +/- 0.1, n = 9; P =.01).. These results indicate that moderate hypothermia may prevent damage to another distant organ, ie the lungs, by preventing recruitment of neutrophils. This may be of benefit in decreasing distal organ damage in diseases in which intestinal ischaemia-reperfusion is implicated in the pathogenesis.

Topics: Animals; Hypothermia, Induced; Intestines; Lung; Lung Diseases; Male; Neutrophil Infiltration; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

A Rho-ROCK signal system induces vascular contraction and neutrophil migration, both of which are characteristic features found with ischemia and reperfusion injury of the liver. We tested our hypothesis that a novel ROCK I inhibitor, Y-27632, attenuates hepatic ischemia and reperfusion injury.. Rats underwent 70% partial hepatic ischemia for 120 minutes and subsequent reperfusion. Y-27632 of 10mg/kg was given orally 1 hour before ischemia, while distilled water was given to the control animals. One week animal survival, systemic hemodynamics, hepatic tissue blood flow, liver function tests, plasma endothelin-1, serum hyaluronic acid levels, myeloperoxidase activity and malondialdehyde level in liver tissue, membrane attack complex-1 and intracellular adhesion molecule-1 staining, and histological architecture were analyzed.. Y-27632 prolonged 1-week animal survival from 25% of untreated animals to 75% accompanied with significant amelioration of hepatic tissue blood flow, liver function tests and histological architecture without any adverse effects on systemic hemodynamics. In addition, plasma endothelin-1 and serum hyaluronic acid levels decreased markedly compared to the control, concomitant with remarkable suppression of membrane attack complex-1 stain positive neutrophils infiltration, myeloperoxidase activity and malondialdehyde level.. Present study suggests that activation of a Rho-ROCK signal system is associated with ischemia and reperfusion injury of the liver, and that Y-27632 may be an attractive agent for application in major liver resection using temporary inflow occlusion and hepatic preservation.

Topics: Alanine Transaminase; Amides; Animals; Blood Pressure; Endothelin-1; Enzyme Inhibitors; Heart Rate; Hyaluronic Acid; Immunohistochemistry; In Situ Nick-End Labeling; Intracellular Signaling Peptides and Proteins; Liver; Liver Circulation; Male; Malondialdehyde; Peroxidase; Protein Serine-Threonine Kinases; Pyridines; Rats; Rats, Sprague-Dawley; Reperfusion Injury; rho-Associated Kinases; Survival Rate

Reactive oxygen metabolites play important roles in ischemia/reperfusion (I/R) injury in several systems. The aim of this study was to investigate the role of melatonin against I/R injury of the rat urinary bladder. The abdominal aorta was clamped to induce ischemia for 30 min, then the animals were subjected to 60 min of reperfusion. Melatonin (10 mg/kg, i.p.) or the vehicle (control 1% alcohol i.p.) was administered before I/R. After decapitation, the bladder was removed and the tissue was either used for functional studies or stored for measurement of products of lipid peroxidation (LP), glutathione (GSH) levels and myeloperoxidase activity (MPO). Bladder strips were suspended in oxygenated Tyrode's buffer at 37 degrees C and isometric contractions to carbachol (CCh; 10(-8)-10(-4) m) were recorded. In the I/R group, the contractile responses of the bladder strips were lower than those of the control group (P < 0.01-0.001) and were reversed by treatment with melatonin (P < 0.05-0.001). LP which was higher in I/R group compared with control (27.68 +/- 1.69 and 10.59 +/- 1.27 nmol/g, respectively; P < 0.001) was partially reversed by melatonin (19.01 +/- 1.85 nmol/g; P < 0.01). Similarly, GSH showed a decrease in the I/R group compared with controls (0.27 +/- 0.03 and 0.43 +/- 0.04 micromol/g, respectively; P < 0.05) and melatonin prevented this effect completely (0.45 +/- 0.04 micromol/g; P < 0.05). MPO activity in the I/R group (4.19 +/- 0.08 U/g) was significantly higher than that of the control group (1.41 +/- 0.08 U/g; P < 0.001) and melatonin treatment reduced MPO levels compared with I/R alone (3.16 +/- 0.07; P < 0.001). Melatonin almost completely reversed the low contractile responses of rat urinary bladder strips to CCh and prevented oxidative tissue damage following I/R.

Topics: Animals; Antioxidants; Carbachol; Cholinergic Agonists; Glutathione; Lipid Peroxidation; Male; Malondialdehyde; Melatonin; Muscle Contraction; Muscle, Smooth; Organ Culture Techniques; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Urinary Bladder

Generation of nitric oxide (NO) by inducible nitric oxide synthase (iNOS) may contribute to renal ischemia/reperfusion (I/R) injury. The aim of this study was to investigate the effects of GW274150, a novel, highly selective, potent and long-acting inhibitor of iNOS activity in rat and mouse models of renal I/R.. Rats were administered GW274150 (5 mg/kg intravenous bolus administered 30 minutes prior to I/R) and subjected to bilateral renal ischemia (45 minutes) followed by reperfusion (6 hours). Serum and urinary indicators of renal dysfunction, tubular and reperfusion injury were measured, specifically, serum urea, creatinine, aspartate aminotransferase (AST) and N-acetyl-beta-d-glucosaminidase (NAG) enzymuria. In addition, renal sections were used for histologic scoring of renal injury and for immunologic evidence of nitrotyrosine formation and poly [adenosine diphosphate (ADP)-ribose] (PAR). Nitrate levels were measured in rat plasma using the Griess assay. Mice (wild-type, administered 5 mg/kg GW274150, and iNOS-/-) were subjected to bilateral renal ischemia (30 minutes) followed by reperfusion (24 hours) after which renal dysfunction (serum urea, creatinine), renal myeloperoxidase (MPO) activity and malondialdehyde (MDA) levels were measured.. GW274150, administered prior to I/R, significantly reduced serum urea, serum creatinine, AST, and NAG indicating reduction of renal dysfunction and injury caused by I/R. GW274150 reduced histologic evidence of tubular injury and markedly reduced immunohistochemical evidence of nitrotyrosine and PAR formation, indicating reduced peroxynitrite formation and poly (ADP-ribose) polymerase (PARP) activation, respectively. GW274150 abolished the rise in the plasma levels of nitrate (indicating reduced NO production). GW274150 also reduced the renal dysfunction in wild-type mice to levels similar to that observed in iNOS-/- mice subjected to I/R. Renal MPO activity and MDA levels were significantly reduced in wild-type mice administered GW274150 and iNOS-/- mice subjected to renal I/R, indicating reduced polymorphonuclear leukocyte (PMN) infiltration and lipid peroxidation.. These results suggest that (1). an enhanced formation of NO by iNOS contributes to the pathophysiology of renal I/R injury and (2). GW274150 reduces I/R injury of the kidney. We propose that selective inhibitors of iNOS activity may be useful against renal dysfunction and injury associated with I/R of the kidney.

Topics: Animals; Creatinine; Enzyme Inhibitors; Kidney; Kidney Diseases; Male; Mice; Mice, Inbred C57BL; Mice, Mutant Strains; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Poly Adenosine Diphosphate Ribose; Rats; Rats, Wistar; Reperfusion Injury; Sulfides; Tyrosine; Urea

We tested a hypothesis that interactions between fibronectin (FN), the major extracellular matrix component, and its integrin alpha 4 beta 1 receptor is important in the development of ischemia/reperfusion injury of steatotic liver transplants. We examined the effect of connecting segment-1 (CS1) peptide-facilitated blockade of FN-alpha 4 beta 1 interaction in a well-established steatotic rat liver model of ex vivo cold ischemia followed by iso-transplantation. In this model, CS1 peptides were administered through the portal vein of steatotic Zucker rat livers before and after cold ischemic storage. Lean Zucker recipients of fatty liver transplants received an additional 3-day course of CS1 peptides after transplant. CS1 peptide therapy significantly inhibited the recruitment of T lymphocytes, neutrophil activation/infiltration, and repressed the expression of proinflammatory tumor necrosis factor-alpha and interferon-gamma. Moreover, it resulted in selective inhibition of inducible nitric oxide synthase expression, peroxynitrite formation, and hepatic necrosis. Importantly, CS1 peptide therapy improved function/histological preservation of steatotic liver grafts, and extended their 14-day survival in lean recipients from 40% in untreated to 100% in CS1-treated OLTs. Thus, CS1 peptide-mediated blockade of FN-alpha 4 beta 1 interaction protects against severe ischemia/reperfusion injury experienced otherwise by steatotic OLTs. These novel findings document the potential of targeting FN-alpha 4 beta 1 in vivo interaction to increase the transplant donor pool through modulation of marginal steatotic livers.

Topics: Animals; Immunohistochemistry; Integrin alpha4beta1; Liver Circulation; Liver Transplantation; Male; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Obesity; Peptide Fragments; Peroxidase; Rats; Rats, Sprague-Dawley; Rats, Zucker; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction

Acute renal failure (ARF) commonly occurs after whole body ischemia. Most experimental models of ARF have relied on the isolated renal artery clamping model; however, there is a pressing need to develop and understand the pathogenesis of new models with more "clinical relevance." We evaluated a new murine model of ARF after whole body ischemia reperfusion injury (WBIRI). WBIRI was induced by an infusion of potassium chloride and a cardiac arrest period of 10 min. Resuscitation was achieved by cardiac compressions, ventilation, epinephrine, and fluids. WBIRI leads to a significant increase in serum creatinine (SCr) and renal tubular injury by 24 h. Renal myeloperoxidase (MPO) levels increased at 24 h after WBIRI. Increased expression of the proinflammatory genes, ICAM-1 and IL-6, was also observed in the kidney following WBIRI. On the basis of recent data that T cells are important mediators of isolated renal IRI, WBIRI was evaluated in T cell-deficient nu/nu mice. T cell-deficient mice had a significantly reduced rise in SCr and decreased tubular injury compared with wild-type mice. T cell-deficient mice had a decrease in ICAM-1 expression after WBIRI, but no decrease in renal MPO. This study describes a new, clinically relevant, model of ARF after WBIRI in mice and identifies the T cell as an important mediator of renal injury following WBIRI. Reduced ICAM-1 expression may provide a mechanism for this involvement.

Topics: Acute Kidney Injury; Animals; Disease Models, Animal; Gene Expression; Inflammation; Intercellular Adhesion Molecule-1; Interleukin-1; Interleukin-6; Kidney; Male; Mice; Mice, Inbred C57BL; Peroxidase; Reperfusion Injury; T-Lymphocytes; Tumor Necrosis Factor-alpha

This study was designed to study the effects of Melatonin (Mel) and N-Acetylcystein (NAC) on hepatic ischemia/reperfusion (I/R) injury in rats. For this purpose Wistar albino rats were subjected to 45 minutes of hepatic ischemia followed by 60 minutes of reperfusion period. Melatonin (10 mg/kg) or NAC (150 mg/kg) were administered alone or in combination, intraperitoneally, 15 minutes prior to ischemia and just before reperfusion. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were determined to assess liver functions. Liver tissues were taken for determination of malondialdehyde (MDA) levels, an end product of lipid peroxidation; glutathione (GSH) levels, a key antioxidant; protein carbonyl concentration (protein oxidation) (PO), a specific marker of oxidative damage of proteins; and myeloperoxidase (MPO) activity, as an indirect index of neutrophil infiltration. Plasma ALT and AST activities were higher in ischemia/reperfusion group than in control. They were decreased in the groups given Mel, NAC or the combination. Hepatic GSH levels, significantly depressed by I/R, were elevated to control levels in the combination group, whereas treatment with Mel or NAC alone provided only a limited protection. Hepatic MDA and PO levels, and MPO activity were significantly increased by I/R. The increase in these parameters were partially decreased by Mel or NAC alone, whereas treatment with the combination reduced these values back to control levels. In conclusion, considering the dosages used, Mel appeared to be significantly more potent than NAC in reversing the oxidative damage induced by I/R. Our findings show that Mel and NAC have beneficial effects against the I/R injury and due to their synergistic effects, when administered in combination, may have a more pronounced protective effects on the liver.

Topics: Acetylcysteine; Animals; Antioxidants; Biomarkers; Female; Free Radical Scavengers; Glutathione; Ischemia; Lipid Peroxidation; Liver; Liver Circulation; Liver Function Tests; Male; Malondialdehyde; Melatonin; Neutrophil Infiltration; Oxidation-Reduction; Peroxidase; Proteins; Rats; Rats, Wistar; Reperfusion Injury

Recent data support a modulatory role for CD4 T cells in experimental renal ischemia-reperfusion injury (IRI). CD4 T cells can functionally differentiate to either a Th1 (IFN-gamma producing) or the counterbalancing Th2 (IL-4) phenotype. The enzymes signal transducers and activators of transcription (STAT) 4 and STAT6 regulate Th1 or Th2 differentiation and cytokine production, respectively. We therefore hypothesized that mice that were STAT4 deficient would be protected from renal IRI and that STAT6-deficient mice would have a more severe course. Intracellular cytokine staining of splenocytes from STAT4-/- or STAT6-/- exhibited distinct IFN-gamma and IL-4 cytokine expression profiles. STAT6-/- had markedly worse renal function and tubular injury postischemia compared with wild type. STAT4-/- had only mildly improved function. Renal phagocyte infiltration and ICAM-1 upregulation were similar in STAT4-/-, STAT6-/-, and wild type. To evaluate if the mechanism of the marked worsening in the STAT6-/- mice could be due to IL-4 deficiency, IL-4-deficient mice were studied and had similar postischemic phenotype to STAT6-/- mice. These data demonstrate that the STAT6 pathway has a major protective role in renal IRI. IL-4 deficiency is a likely mechanism underlying the STAT6 effect. A "yin-yang" role for inflammation is emerging in renal IRI, similar to recent observations in atherosclerosis.

Topics: Animals; DNA-Binding Proteins; Female; Gene Expression; Intercellular Adhesion Molecule-1; Interferon-gamma; Interleukin-1; Interleukin-4; Interleukin-6; Kidney; Leukocyte Count; Male; Mice; Mice, Inbred BALB C; Mice, Knockout; Neutrophils; Peroxidase; Phenotype; Reperfusion Injury; Signal Transduction; STAT4 Transcription Factor; STAT6 Transcription Factor; Th1 Cells; Th2 Cells; Trans-Activators; Tumor Necrosis Factor-alpha

We investigated kidney and lung alterations caused by intercellular adhesion molecule type 1 (ICAM-1) blockade after ischemia and reperfusion of hind limb skeletal muscles. Rats were submitted to ligature of the infrarenal aorta for 6 h. The animals were randomized into three groups of 6 rats each: group I, sacrificed after ischemia; group II, reperfusion for 24 h, and group III, reperfusion for 24 h after receiving monoclonal anti-ICAM-1 antibodies. At the end of the experiment, blood samples were collected for creatinine, lactate dehydrogenase, creatine phosphokinase, potassium, pH and leukocyte counts. Samples were taken from the muscles of the hind limbs and from the kidneys and lungs for histological analysis and measurement of the neutrophil infiltrate by myeloperoxidase staining. The groups did not differ significantly with regard to the laboratory tests. There were no major histological alterations in the kidneys. An intense neutrophil infiltrate in the lungs, similar in all groups, was detected. Myeloperoxidase determination showed that after reperfusion there was significantly less retention of polymorphonuclear neutrophils in the muscles (352 +/- 70 vs 1451 +/- 235 x 10(2) neutrophils/mg; P<0.01) and in the kidneys (526 +/- 89 vs 852 +/- 73 10(2) neutrophils/mg; P<0.01) of the animals that received anti-ICAM-1 before perfusion compared to the group that did not. The use of anti-ICAM-1 antibodies in this experimental model minimized neutrophil influx, thus reducing the inflammatory process, in the muscles and kidneys after ischemia and reperfusion of the hind limbs.

Topics: Animals; Antibodies, Monoclonal; Cell Adhesion; Hindlimb; Intercellular Adhesion Molecule-1; Ischemia; Kidney; Lung; Muscle, Skeletal; Neutrophils; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Intestinal ischemia/reperfusion (IIR) is a critical and triggering event in the development of distal organ dysfunction, frequently involving the lungs. Respiratory failure is a common cause of death and complications after intestinal I/R. Stress protein heme oxygenase-1 (HO-1) confers the protection against a variety of oxidant-induced cell and tissue injuries. The aim of this study was to investigate the hypothesis that the induced HO-1 expression by pharmacological preconditioning with anticancer drug doxorubicin (Dox) could protect the lung injury induced by intestinal I/R. Intravenous administration of Dox induced HO-1 expression in the lungs and high levels of the expression were sustained at least to 48 h after the injection. Therefore, as pharmacological preconditioning, a low dose of Dox was injected intravenously into rats at 48 h before the start of intestinal ischemia. Rats underwent intestinal I/R by superior mesenteric artery occlusion for 120 min followed by 120 min of reperfusion. Preconditioning with Dox significantly ameliorated the lung injury induced by the intestinal I/R. Administration of a specific inhibitor of HO activity reduced the efficacy of the preconditioning. Our results suggest that this improvement may be mediated at least in part by the HO-1 induction. These findings may offer interesting perspectives for patient management In Intestinal surgical operation and intestine transplantation.

Topics: Animals; Disease Models, Animal; Heme Oxygenase (Decyclizing); Heme Oxygenase-1; Intestines; Ischemic Preconditioning; Lung; Male; Peroxidase; Pulmonary Circulation; Rats; Rats, Wistar; Reperfusion Injury

Acute renal failure results in significant morbidity and mortality, yet renal failure is not the usual cause of death in the clinical situation. We have previously reported systemic increases in the inflammatory mediators tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1) after renal ischemia in the mouse. In the present study, an animal model of bilateral renal ischemia was used to test the hypothesis that cytokines released with renal ischemia have effects on other organ systems. Increased levels of immunoreactive TNF-alpha and IL-1 and intercellular adhesion molecule-1 mRNA were found in the heart after renal ischemia in the rat. This was accompanied by increases in myeloperoxidase activity, an index of tissue leukocyte infiltration, in the heart as well as the liver and lung. Functional changes in the heart 48 h after renal ischemia included increases in left ventricular end diastolic diameter, left ventricular end systolic diameter, and decreased fractional shortening by echocardiography. Evidence of apoptosis of cardiac cells was also found 48 h after an abbreviated period of renal ischemia insufficient to induce azotemia but not bilateral nephrectomy (which resulted in significant renal failure), suggesting that renal ischemia but not uremia is necessary for the apoptosis observed. It was also found that blocking the action of TNF-alpha limited cardiac apoptosis. Renal ischemia results in distant effects and the alterations observed in the heart may be important in the morbidity and mortality observed clinically.

Topics: Animals; Apoptosis; Blood Pressure; Heart; Intercellular Adhesion Molecule-1; Interleukin-1; Male; Myocardium; Peroxidase; Rats; Rats, Sprague-Dawley; Renal Circulation; Reperfusion Injury; RNA, Messenger; Systole; Tumor Necrosis Factor-alpha

The objective of this study was to investigate the effects of Daflon 500 mg on tissue damage in kidney after ischemia/reperfusion hindlimb, by assessing blood biochemical assay and histopathological analysis. Rats were given Daflon 80 mg x kg(-1) x day(-1) for 10 days. On 11th day of treatment, 4h ischemia followed by 4 h reperfusion period was performed on right hind limb of the rats. Control groups were given only arabic gum and were subjected to same ischemia/reperfusion period. At the end of reperfusion period, erythrocyte superoxide dismutase, Na(+)-K(+) ATPase and reduced glutathione levels were increased in the rats erythrocytes in Daflon group (P<0.01, for all). On the other hand, serum myeloperoxidase and malondialdehyde levels were significantly lower in the Daflon-received rats (P<0.01, for all). Histopathological studies demonstrated that, there was a prominent tubulointerstitial injury with loss of brush border and this degeneration was accompanied by segmental glomerular degeneration also for both control and Daflon group. Daflon-received group animals displayed significantly less periglomerular and perivascular leukocytic infiltration (P=0.015). These overall results suggest that Daflon contributes renal protection from hind limb ischemia/reperfusion injury in some degree, by decreasing systemic oxidative stress.

Topics: Animals; Diosmin; Glutathione; Hindlimb; Kidney; Male; Malondialdehyde; Nephritis, Interstitial; Oxidative Stress; Peroxidase; Protective Agents; Rats; Rats, Wistar; Reperfusion Injury; Sodium-Potassium-Exchanging ATPase; Superoxide Dismutase

The aim of this study was to investigate the efficacy and mechanism of action of a noninvasive remote ischemic preconditioning (IPC) technique for the protection of multiple distant skeletal muscles against ischemic necrosis (infarction). It was observed in the pig that three cycles of 10-min occlusion and reperfusion in a hindlimb by tourniquet application reduced the infarction of latissimus dorsi (LD), gracilis (GC), and rectus abdominis (RA) muscle flaps by 55%, 60%, and 55%, respectively, compared with their corresponding control (n = 6, P < 0.01) when they were subsequently subjected to 4 h of ischemia and 48 h of reperfusion. This infarct-protective effect of remote IPC in LD muscle flaps was abolished by an intravenous bolus injection of the nonselective opioid receptor antagonist naloxone (3 mg/kg) 10 min before remote IPC and a continuous intravenous infusion (3 mg/kg) during remote IPC and by an intravenous bolus injection of the selective delta 1-opioid receptor antagonist 7-benzylidenealtrexone maleate (3 mg/kg). However, this infarct-protective effect of remote IPC was not affected by an intravenous bolus injection of the ganglionic blocker hexamethonium chloride (20 mg/kg) or the nonspecific adenosine receptor antagonist 8-(p-sulfophenyl)theophylline (10 mg/kg) or by a local intra-arterial injection of the adenosine1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (3 mg/muscle flap) given 10 min before remote IPC. It was also observed that this remote IPC of skeletal muscle against infarction was associated with a slower rate of muscle ATP depletion during the 4 h of sustained ischemia and a reduced muscle neutrophilic myeloperoxidase activity after 1.5 h of reperfusion. These observations led us to speculate that noninvasive remote IPC by brief cycles of occlusion and reperfusion in a pig hindlimb is effective in global protection of skeletal muscle against infarction. This infarct-protective effect is most likely triggered by the activation of opioid receptors in the skeletal muscle, and remote IPC is associated with an energy-sparing effect during sustained ischemia and attenuation of neutrophil accumulation during reperfusion.

Topics: Abdomen; Adenosine Triphosphate; Animals; Ganglionic Blockers; Hexamethonium; Hindlimb; Infarction; Ischemic Preconditioning; Lactic Acid; Male; Muscle, Skeletal; Narcotic Antagonists; Neutrophils; Peroxidase; Reperfusion Injury; Surgical Flaps; Swine; Thigh; Thorax

High-density lipoproteins (HDL) have been shown to reduce organ injury and mortality in animal models of shock via modulation of the expression of adhesion molecules and pro-inflammatory enzymes. As renal inflammation plays an important role in the development of ischemia/reperfusion (I/R) injury of the kidney, the aim of this study was to investigate the ability of HDL to alleviate renal dysfunction and injury in a rat model of renal I/R. HDL (80 mg/kg, intravenous) was administered to male Wistar rats 30 min before bilateral renal ischemia for 45 min followed by reperfusion for up to 48 h. After 6-h reperfusion, HDL significantly reduced (1) renal and tubular dysfunction, (2) tubular and reperfusion-injury, and (3) histologic evidence of renal injury. HDL also improved renal function (after 24-h and 48-h reperfusion) and reduced histologic signs of renal injury (after 48-h reperfusion). Administration of HDL significantly reduced the numbers of polymorphonuclear leukocytes (PMN) infiltrating into renal tissues during reperfusion, which was reflected by an attenuation of the increase in renal myeloperoxidase activity caused by I/R. Furthermore, HDL markedly reduced expression of the adhesion molecules, intercellular adhesion molecule-1 (ICAM-1), and P-selectin during reperfusion. The increase in renal malondialdehyde levels caused by renal I/R was also significantly reduced by HDL, suggesting attenuation of lipid peroxidation subsequent to oxidative stress. These results demonstrate that HDL significantly reduces renal I/R injury and severity of ischemic acute renal failure. It is proposed that the mechanism of protection involves reduction of the expression of adhesion molecules, resulting in reduction of PMN infiltration and oxidative stress.

Topics: Acetylglucosaminidase; Animals; Aspartate Aminotransferases; Immunohistochemistry; Inflammation; Intercellular Adhesion Molecule-1; Lipoproteins, HDL; Male; Malondialdehyde; Neutrophils; Oxidative Stress; P-Selectin; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Time Factors

Peroxynitrite is a potent cytotoxic free radical produced by the reaction of nitric oxide with the superoxide ion produced in conditions of oxidative stress. The purpose of the study was to examine the role of this reactive nitrogen species in lung ischemia-reperfusion injury.. Left lungs of male Long-Evans rats were rendered ischemic for 90 minutes and reperfused for up to 4 hours. Treated animals received FP-15 (a water-soluble iron containing metalloporphyrin that acts as a peroxynitrite decomposition catalyst). Injury was quantitated in terms of tissue neutrophil accumulation (myeloperoxidase content) and vascular permeability ((125)I bovine serum albumin [BSA] extravasation) and bronchoalveolar lavage cytokine, transcriptional factor and leukocyte content. Separate tissue samples were processed for immunohistology and nuclear protein analysis.. Lung vascular permeability was reduced in treated animals by 61% compared with control animals (p < 0.005). The protective effects of enhanced peroxynitrite decomposition correlated with a 72% reduction in tissue myeloperoxidase content (p < 0.001) and marked reductions in brochoalveolar lavage leukocyte accumulation. This correlated positively with the diminished expression of pro-inflammatory chemokines and nuclear transcription factors.. The deleterious effects of lung ischemia-reperfusion injury are in part mediated by the formation of peroxynitrite, as enhanced decomposition of this species is protective in this model. The development of potent water-soluble decomposition catalysts represents a potentially useful therapeutic tool in the prevention of lung ischemia-reperfusion injury after lung transplantation.

Topics: Animals; Bronchoalveolar Lavage Fluid; Capillary Permeability; Chemokines; Disease Models, Animal; Immunohistochemistry; Inflammation Mediators; Macrophages, Alveolar; Male; Models, Cardiovascular; NF-kappa B; Peroxidase; Peroxynitrous Acid; Rats; Rats, Long-Evans; Reactive Nitrogen Species; Reperfusion Injury; Respiratory Distress Syndrome; Severity of Illness Index; Statistics as Topic; Transcription Factor AP-1; Transcriptional Activation; Tyrosine

Oxidative stress after ischemia and reperfusion leads to leukocyte activation, the production of injurious cytokines, and increased expression of inflammatory adhesion molecules. This initial event is one of the most important alloantigen-independent factors associated with graft coronary artery disease (GCAD). Cyclic adenosine monophosphate (cAMP) is an important second messenger that inhibits the expression of tumor necrosis factor alpha (TNF-alpha), vascular cell adhesion molecule 1 (VCAM-1), and endothelial leukocyte adhesion molecule 1 (ELAM-1) in vitro. Its levels decrease during organ preservation. We hypothesized that augmenting allograft cAMP levels with the water-soluble adenylate cyclase activator, NKH477, could decrease ischemia-reperfusion injury and inhibit the progression of GCAD.. PVG to ACI rat heterotopic cardiac allografts, treated with NKH477 solution or vehicle, were reperfused for 4 hours or 90 days after 60 minutes of ischemia. We analyzed grafts for intracellular adhesion molecule 1 (ICAM-1), VCAM-1, and ELAM-1 mRNA expression; TNF-alpha and interleukin-6 (IL-6) protein expression; and myeloperoxidase activity. We also performed immunohistochemical analysis for ICAM-1 and VCAM-1 protein expression. At post-operative Day 90, the progression of GCAD had increased morphometrically.. NKH477-treated grafts had significantly decreased levels of myeloperoxidase activity compared with controls. In this group, TNF-alpha, IL-6, and VCAM-1 protein expression was inhibited; however, ICAM-1 and ELAM-1 expression did not alter. We found no differences in the degree of development of GCAD between groups.. Although augmented intracellular cAMP prevented acute reperfusion injury, it was insufficient to prevent the development of GCAD. Intracellular adhesion molecule 1 and ELAM-1, whose expression NKH477 does not inhibit, may play important roles in the development of GCAD.

Topics: Animals; Cardiotonic Agents; Cell Movement; Colforsin; Coronary Artery Disease; Cyclic AMP; Disease Models, Animal; E-Selectin; Endothelium, Vascular; Heart Transplantation; Immunoenzyme Techniques; Immunohistochemistry; Intercellular Adhesion Molecule-1; Interleukin-6; Male; Models, Cardiovascular; Myocytes, Cardiac; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Transplantation, Homologous; Tumor Necrosis Factor-alpha; Up-Regulation; Vascular Cell Adhesion Molecule-1

Reperfusion injury contributes to early organ malfunction after transplantation. The aim of this study was to characterize the ischemia-reperfusion injury after pancreas transplantation and to evaluate the effect of monoclonal antibody therapy against ICAM-1.. Twenty-five heterotopic pancreas transplantations were performed in syngenic rats in a no-touch technique. Microcirculation and leukocyte-endothelial interaction in the grafts were evaluated by intravital microscopy at 1 hour (I), 6 hours (II), 12 hours (III), and 24 hours (IV) after reperfusion, and 12 hours after reperfusion (V) in the therapeutic group. In (V) antibodies against ICAM-1 were applied as bolus at reperfusion and continuously for 6 hours. Next to intravital microscopy, histologic scores, myeloperoxidase levels, and ICAM-1 expression were determined.. Microcirculation was significantly reduced in capillaries and postcapillary venules in the time course after reperfusion (capillary: 0.96 +/- 0.08 mm/s [I] to 0.45 +/- 0.07 mm/s [IV] [P <.01]) and was improved significantly by therapy with ICAM-1 antibodies (0.98 +/- 0.06 mm/s, (P <.01). Leukocyte-endothelial interaction significantly increased 6 hours after reperfusion (II) (P <.01). These changes were paralleled by an increased endothelial expression of ICAM-1 in immunohistochemistry. Histologic evaluation showed increased inflammation at 12 hours after reperfusion (P <.01), which could be diminished by the administration of ICAM-1 antibodies (P <.05).. Increased endothelial expression of ICAM-1 after pancreas transplantation is positively correlated with microcirculatory impairment. Important steps of pancreatic inflammation take place approximately 6 hours after reperfusion. Prophylactic application of monoclonal antibodies against ICAM-1 reduces reperfusion injury and successfully prevents the occurrence of graft pancreatitis.

Topics: Animals; Antibodies, Monoclonal; Cell Adhesion; Hemodynamics; Immunohistochemistry; Intercellular Adhesion Molecule-1; Leukocytes; Male; Microcirculation; Pancreas; Pancreas Transplantation; Peroxidase; Rats; Rats, Inbred Lew; Reperfusion Injury

Activation of the alveolar macrophage is critical to the development of nonischemic inflammatory lung injury. The present studies were undertaken to determine whether the alveolar macrophage plays a similarly important role in lung ischemia-reperfusion injury.. The left lungs of male rats were rendered ischemic for 90 minutes and reperfused for up to 4 hours. Treated animals received liposome-encapsulated clodronate, which depletes alveolar macrophages. Injury was quantitated in terms of vascular permeability, tissue neutrophil accumulation, and bronchoalveolar lavage fluid leukocyte, chemokine, and cytokine content. Lung homogenates were also analyzed for nuclear translocation of the transcription factors nuclear factor kappaB and activator of protein 1.. Depletion of alveolar macrophages reduced lung vascular permeability by 53% compared with that seen in control animals (permeability indices: 0.88 +/- 0.07 to 0.46 +/- 0.04, P <.001). The protective effects of alveolar macrophage depletion correlated with a 50% reduction in tissue myeloperoxidase content (0.62 +/- 0.07 to 0.33 +/- 0.03, P <.006) and marked reductions in bronchoalveolar lavage fluid leukocyte accumulation. Alveolar macrophage-depleted animals also demonstrated marked reductions of the elaboration of multiple proinflammatory chemokines and cytokines in the lavage effluent and nuclear transcription factors in lung homogenates.. It is likely that the alveolar macrophage is the key early source of multiple proinflammatory mediators that orchestrate lung ischemia-reperfusion injury. Depleting alveolar macrophages is protective against injury, supporting its central role in oxidant stress-induced cytokine and chemokine release and the subsequent development of lung injury.

Topics: Animals; Bronchoalveolar Lavage Fluid; Capillary Permeability; Cytokines; Disease Models, Animal; Leukocyte Count; Liposomes; Lung Diseases; Macrophage Activation; Macrophages, Alveolar; Male; Models, Cardiovascular; Neutrophils; NF-kappa B; Peroxidase; Rats; Rats, Long-Evans; Reperfusion Injury; Time Factors; Transcription Factor AP-1

To explore the role of TLR4 in the mechanism of hepatic ischemia/reperfusion (I/R) injury in mice.. Wild-type (C3H/Heouj) mice and TLR4 deficient mice (C3H/Hej) were used to prepare the models of liver I/R injury. Partial hepatic ischemia was produced by inflow causing occlusion in the median and left lobes for 45 minutes. Blood was drawn to kill the mice at 1 hours and 3 hours after reperfusion. The blood was used to analyze aspartate aminotransferase (AST) and tumor necrosis factor-alpha (TNFalpha). TNF-alpha mRNA expression and myeloperoxidase (MPO) level in ischemic lobes was examined by northern blot and myeloperoxidase assay, respectively.. AST levels were significantly lower in TLR4 deficient mice, compared with those in wild-type mice at both time points (661.83U/L+/-106.09U/L vs. 1215.5U/L+/- 174.03U/L, t=-6.65, P<0.01; 1145.17U/L+/-132.42U/L vs. 2958.17U/L+/-186.81U/L, t=-5.57, P<0.01). Serum TNF-alpha level was lower in TLR4 deficient mice at 3 hours after reperfusion compared with that in wild-type mice (152.39pg/ml+/-43.3 pg/ml vs. 249.12pg/ml+/-51.89pg/ml, t=-3.13, P<0.05). This difference appeared to be mediated at the gene level, since TNF-alpha mRNA expression had decreased in TLR4 deficient mice at 1 hours after reperfusion, compared with that in wild type mice (80.3+/-28.8 vs. 189.4+/-24.6, t=-3.25, P<0.05). MPO level in ischemic lobes in TLR4 deficient mice at 3 hours after reperfusion was significantly lower than that in wild type mice (F=33.49, P<0.01).. I/R hepatic injury in TLR4 deficient mice is less than that in wild-type mice. TNF-alpha expression down-regulated at the mRNA level appears critical. These suggest that TLR4 be involved in the mechanism of hepatic ischemia/reperfusion injury in mice.

Topics: Alanine Transaminase; Animals; Liver; Membrane Glycoproteins; Mice; Mice, Inbred C3H; Peroxidase; Receptors, Cell Surface; Reperfusion Injury; RNA, Messenger; Toll-Like Receptor 4; Toll-Like Receptors; Tumor Necrosis Factor-alpha

This study was designed to investigate the role of apoptosis on liver IR injury and to determine the effects of roscovitine on this process.. Rat livers pretreated with roscovitine received 60 min right lobe ischemia followed by 4 h (n=8) and 24 h (n=8) reperfusion. Tissue injury was evaluated by serum alanine aminotransferase, aspartate aminotransferase, tissue malondialdehyde, myeloperoxidase measurements and histological examination. Dead (apoptotic and necrotic) hepatocytes were determined by trypan blue dye and apoptosis was evaluated with M30 monoclonal antibody.. Administration of roscovitine significantly decreased both apoptotic and dead hepatocyte counts compared to controls (P<0.01). Liver transaminase levels were decreased significantly in the roscovitine-pretreated groups (P<0.05). In the groups evaluated 24 h after reperfusion, MPO levels (P<0.02) and leukocyte infiltration on histologic sections were decreased significantly in the roscovitine-administered group compared to its control.. This study indicates that hepatocyte apoptosis may play a role in the development of IR injury of the liver. Administration of roscovitine may be beneficial in preventing this injury.

Topics: Alanine Transaminase; Animals; Apoptosis; Aspartate Aminotransferases; Disease Models, Animal; Enzyme Inhibitors; Liver; Male; Malondialdehyde; Peroxidase; Purines; Rats; Rats, Wistar; Reperfusion Injury; Roscovitine

The aim of this study was to investigate the effects of caffeic acid phenethyl ester (CAPE) on the lungs as a remote organ after performing hindlimb ischemia-reperfusion (I/R) and by assessing biochemical and histopathological analysis.. The animals were divided into three groups: control, I/R, and I/R with CAPE. I/R period for 8 h was performed on the right hindlimb of all the anesthesied rats in I/R and CAPE with I/R group. In the CAPE with I/R group, the animals received CAPE 10 microM by intraperitoneal injection 1h before the reperfusion. The animals in the control and I/R groups received a similar volume of saline solution by means of intraperitoneal injection. At the end of the reperfusion period, a midsternotomy was performed. Blood, bronchoalveolar lavage (BAL) and lung tissue were obtained, and were used for biochemical and histopathological examination.. The tissue and serum malondyaldehyde levels were significantly lower in the control (P=0.0001 and 0.001, respectively) and in the CAPE with I/R groups (P=0.0001 and 0.003, respectively) compared to the I/R group. Tissue Na(+)-K(+) ATPase activity in the CAPE with I/R group was significantly higher than in the I/R group (P=0.0001). Reduced activity was found in the I/R group compared to the control group (P=0.0001). Myeloperoxidase activity (P=0.001) and protein concentration (P=0.034) in BAL were significantly reduced in CAPE-treated animals when compared with the I/R group. A decreased activity and protein concentration were found in the control group compared to the I/R group (P=0.0001 and 0.024, respectively). The lungs of the I/R group displayed intense peribronchial and perivascular leukocytic infiltration in histopathological examination compared to the CAPE with I/R group (P<0.05).. CAPE seems to be effective in protecting remote organ injury caused by increased oxidative stress and neutrophil accumulation that results from an I/R injury.

Topics: Animals; Bronchoalveolar Lavage; Bronchoalveolar Lavage Fluid; Caffeic Acids; Capillary Permeability; Hindlimb; Injections, Intraperitoneal; Lung; Male; Malondialdehyde; Neutrophil Infiltration; Peroxidase; Phenylethyl Alcohol; Proteins; Rats; Rats, Wistar; Reperfusion Injury; Respiratory Distress Syndrome; Sodium-Potassium-Exchanging ATPase; Time Factors; Tourniquets; Turkey

In the present study, we used 5-lipoxygenase (5-LO) knockout (KO) mice to evaluate the possible role of 5-LO on the pathogenesis of splanchnic artery occlusion (SAO) shock. SAO shock was induced in mice by clamping both the superior mesenteric artery and the celiac artery for 30 min, followed thereafter by release of the clamp (reperfusion). At 120 min after reperfusion, animals were sacrificed for histological examination and biochemical studies. There was a marked increase in the lipid peroxidation in the ileum as well as in the lung of the SAO-shocked 5-LO wild-type (WT) mice after reperfusion. The absence of 5-LO did not reduce the lipid peroxidation in the intestine or the lung. SAO-shocked WT mice developed a significant increase of tissue (ileum and lung) myeloperoxidase activity and marked histological injury. SAO shock was also associated with a significant mortality (50% survival at 5 h after reperfusion). Reperfused ileum and lung tissue sections from SAO-shocked WT mice showed positive staining for P-selectin, ICAM-1, and E-selectin that was mainly localized in the vascular endothelial cells. The intensity and degree of P-selectin, E-selectin, and ICAM-1 were markedly reduced in tissue section from SAO-shocked 5-LOKO mice. SAO-shocked 5-LOKO mice showed also a significant reduction of the neutrophils infiltration into the reperfused intestine as well as in the lung as evidenced by reduced myeloperoxidase activity, an improved histological status of the reperfused tissues, and an improved survival. Taken together, our results clearly demonstrate that 5-LO plays an important role in ischemia and reperfusion injury and put forward the hypothesis that inhibition of 5-LO may represent a novel and possible strategy in the treatment of ischemia and reperfusion injury. Part of this effect may be due to inhibition of the expression of adhesion molecules and subsequent reduction of neutrophil-mediated cellular injury.

Topics: Animals; Arachidonate 5-Lipoxygenase; Arterial Occlusive Diseases; Densitometry; E-Selectin; Ileum; Immunohistochemistry; Intercellular Adhesion Molecule-1; Intestines; Leukotrienes; Lipid Peroxidation; Lung; Male; Mice; Mice, Knockout; Neutrophils; P-Selectin; Peroxidase; Reperfusion Injury; Shock; Thiobarbituric Acid Reactive Substances; Time Factors

Statins are lipid-lowering drugs with anti-inflammatory and antioxidant properties. This study explores the potential of these commonly prescribed agents to ameliorate lung ischemia-reperfusion injury.. Left lungs of Long-Evans rats were rendered ischemic for 90 minutes and reperfused for up to 4 hours. Treated animals received simvastatin orally (0.5 mg/kg) for 5 days before the experiment. Injury was quantitated in terms of tissue myeloperoxidase content, vascular permeability ((125)I bovine serum albumin extravasation), and bronchoalveolar lavage leukocyte and cytokine content. Changes in nuclear translocation of transcription factors were evaluated by electromobility shift assay. Additional animals received N(G)-nitro-L-arginine methyl ester before ischemia-reperfusion to assess whether inhibition of nitric oxide synthase could reverse simvastatin's protective effects. The presence of nicotinamide adenine dinucleotide phosphate oxidase was also evaluated using enzyme staining both histologically and in native electrophoresis.. Lung vascular permeability was reduced in treated animals by 71% compared with positive controls (P <.001). Administration of N(G)-nitro-L-arginine methyl ester reversed this protection. The protective effects of statin pretreatment correlated with a 68% reduction in tissue myeloperoxidase content (P <.01), marked reductions in bronchoalveolar lavage leukocyte accumulation, and decreased expression of proinflammatory cytokines. Nicotinamide adenine dinucleotide phosphate oxidase expression also decreased with statin treatment.. In addition to its antioxidant properties, the protective effects of simvastatin are likely mediated by modulation of endothelial nitric oxide synthase. The potential to pretreat recipients of lung transplantation with statins to ameliorate reperfusion injury is promising.

Topics: Animals; Bronchoalveolar Lavage Fluid; Capillary Permeability; Cell Count; Cytokines; Disease Models, Animal; Enzyme Inhibitors; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Hypolipidemic Agents; Ischemia; Lung; Lung Diseases; Male; Models, Cardiovascular; NADPH Oxidases; NG-Nitroarginine Methyl Ester; Nitric Oxide Synthase; Peroxidase; Rats; Rats, Long-Evans; Reperfusion Injury; Simvastatin; Statistics as Topic; Time Factors; Transcription Factors; Treatment Outcome

Acutely increased intra-abdominal pressure (IAP) can lead to multiple organ failure. As blood flow to intra-abdominal organs is reduced by high venous resistance, ischemia-reperfusion (I/R) injury plays an important role in the pathogenesis of abdominal compartment syndrome (ACS) following IAP. Melatonin, a secretory product of the pineal gland, is known to have free radical scavenging and antioxidative properties in several oxidative processes. The objective of this study was to examine the potential protective properties of melatonin on the oxidative organ damage in a rat model of ACS. Under ketamine anesthesia, an arterial catheter was inserted intraperioneally (i.p.) and using an aneroid manometer connected to the catheter, IAP was kept at 20 mmHg (ischemia group; I) for 1 hr. In the ischemia/reperfusion (I/R) group, pressure applied for an hour was decompressed and a 1-hr reperfusion period was allowed. In another IR group, melatonin was administered (10 mg/kg, i.p.) immediately before the decompression of IAP. The results demonstrate that tissue levels of malondialdehyde (MDA) and myeloperoxidase activity (MPO; index of tissue neutrophil infiltration) were elevated, while glutathione (GSH; a key to antioxidant) levels were reduced in both I and I/R groups (P < 0.05-0.001). Melatonin treatment in I/R rats reversed these changes (P < 0.01-0.001). Moreover, melatonin given to the I/R group reduced the elevations in serum aspartate aminotransferase, alanine aminotransferase and blood urea nitrogen levels and abolished the increase in serum creatinine levels. Our results indicate that melatonin, because of antioxidant and free radical scavenging properties, ameliorates reperfusion-induced oxidative organ damage. In conclusion, the results of the present study suggest that the therapeutic value of melatonin as a 'reperfusion injury-limiting' agent must be considered in ACS.

Topics: Abdomen; Animals; Compartment Syndromes; Free Radical Scavengers; Glutathione; Ischemia; Lipid Peroxidation; Malondialdehyde; Melatonin; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

1. The peroxisome proliferator-activated receptor-gamma (PPAR-gamma) is a member of the nuclear receptor superfamily of ligand-dependent transcription factors related to retinoid, steroid and thyroid hormone receptors. The thiazolidinedione rosiglitazone and the endogenous cyclopentenone prostaglandin (PG)D2 metabolite, 15-deoxy-Delta12,14-PGJ2 (15d-PGJ2), are two PPAR-gamma ligands, which modulate the transcription of target genes. 2. The aim of this study was to investigate the effect of rosiglitazone and 15d-PGJ2 on the tissue injury caused by ischaemia/reperfusion (I/R) of the gut. 3. I/R injury of the intestine was caused by clamping both the superior mesenteric artery and the coeliac trunk for 45 min, followed by release of the clamp allowing reperfusion for 2 or 4 h. This procedure results in splanchnic artery occlusion (SAO) shock. 4. Rats subjected to SAO developed a significant fall in mean arterial blood pressure, and only 10% of the animals survived for the entire 4 h reperfusion period. Surviving animals were killed for histological examination and biochemical studies. Rats subjected to SAO displayed a significant increase in tissue myeloperoxidase (MPO) activity and malondialdehyde (MDA) levels, significant increases in plasma tumour necrosis factor (TNF)-alpha and interleukin (IL)-1beta levels and marked injury to the distal ileum. 5. Increased immunoreactivity to nitrotyrosine was observed in the ileum of rats subjected to SAO. Staining of sections of the ileum obtained from SAO rats with anti-intercellular adhesion molecule (ICAM-1) antibody resulted in diffuse staining. 6. Administration at 30 min prior to the onset of gut ischaemia of the two PPAR-gamma agonists (rosiglitazone (0.3 mg kg-1 i.v.) and 15d-PGJ2 (0.3 mg kg-1 i.v.)) significantly reduced the (i) fall in mean arterial blood pressure, (ii) mortality rate, (iii) infiltration of the reperfused intestine with polymorphonuclear neutrophils (MPO activity), (iv) lipid peroxidation (MDA levels), (v) production of proinflammatory cytokines (TNF-alpha and IL-1beta) and (vi) histological evidence of gut injury. Administration of rosiglitazone and 15d-PGJ2 also markedly reduced the nitrotyrosine formation and the upregulation of ICAM-1 during reperfusion. 7. In order to elucidate whether the protective effects of rosiglitazone and 15d-PGJ2 are related to the activation of the PPAR-gamma receptor, we also investigated the effect of a PPAR-gamma antagonist, bisphenol A diglycidyl ether (BA

Topics: Animals; Benzhydryl Compounds; Blood Pressure; Epoxy Compounds; Immunologic Factors; Intercellular Adhesion Molecule-1; Interleukin-1; Intestinal Mucosa; Intestines; Ligands; Male; Malondialdehyde; Peroxidase; Prostaglandin D2; Rats; Rats, Sprague-Dawley; Receptors, Cytoplasmic and Nuclear; Reperfusion Injury; Rosiglitazone; Thiazolidinediones; Transcription Factors; Tumor Necrosis Factor-alpha; Tyrosine; Vasodilator Agents

Reactive nitrogen and oxygen species are implicated in the damage of ischemic tissue that is reperfused. One important pathway may involve xanthine oxidase. Xanthine oxidase uses xanthine, a product of ATP degradation in ischemic tissue, to produce superoxide and hydrogen peroxide. Superoxide reacts rapidly with nitric oxide to form peroxynitrite, a powerful oxidant. Another potential source of reactive nitrogen species is the myeloperoxidase-hydrogen peroxide-nitrite system of activated phagocytes. We demonstrate that peroxynitrite and myeloperoxidase nitrate xanthine in vitro. Through 13C NMR spectroscopy, UV/visible spectroscopy, and mass spectrometry, the major product was identified as 8-nitroxanthine. Xanthine nitration by peroxynitrite was optimal at neutral pH and was markedly stimulated by physiological concentrations of bicarbonate. Xanthine nitration by myeloperoxidase required hydrogen peroxide and nitrite. However, it was independent of chloride ion and little affected by scavengers of hypochlorous acid, suggesting that the reactive agent is a nitrogen dioxide-like species. 8-Nitroxanthine was generated by a low, steady flux of peroxynitrite, and also by the myeloperoxidase-hydrogen peroxide-nitrite system of activated human neutrophils, suggesting that the reactions may be physiologically relevant. 8-Nitroxanthine may exert biological effects because it markedly increased the production of superoxide by the xanthine oxidase-xanthine system. Our observations suggest a mechanism for the enhanced formation of superoxide in reperfused tissue, which might increase the production of peroxynitrite and 8-nitroxanthine. Generation of 8-nitroxanthine by peroxynitrite and myeloperoxidase could represent a positive feedback mechanism that enhances further the production of both reactive oxygen and nitrogen species in ischemic tissue that is reperfused.

Topics: Humans; Neutrophil Activation; Neutrophils; Peroxidase; Peroxynitrous Acid; Reperfusion Injury; Superoxides; Xanthine Oxidase; Xanthines

The present work examined whether polymorphonuclear neutrophil (PMN) infiltration contributes to cortical and striatal brain damage and oxidative stress in a model of transient focal cerebral ischemia. A 2-h occlusion of the left middle cerebral artery and ipsilateral common carotid artery was performed in rats. Administration of the neutropenic agent vinblastine (0.5 mg/kg, i.v.) resulted in a profound decrease in circulating PMNs which was associated with a 80% decrease in myeloperoxidase activity, a marker of PMN infiltration, in both the cortex and the striatum. In the cortex, vinblastine-treated animals exhibited a 44% decrease in the infarct volume and also reduced the oxidative stress (evaluated by the decrease in glutathione concentrations). By contrast, in the striatum, neutropenia modified neither the lesion size nor the oxidative stress. These results indicate that PMN contribution to postischemic injury and oxidative stress is dependent on the brain structure.

Topics: Animals; Antineoplastic Agents, Phytogenic; Brain Ischemia; Cerebral Cortex; Corpus Striatum; Male; Neutrophil Infiltration; Neutrophils; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Vinblastine

To assess the physiologic and biochemical changes resulting from ischemia and reperfusion. Effective therapy for ischemic priapism reestablishes corporal venous outflow and arterial inflow and results in increased corporal partial pressure of oxygen. Data are limited concerning reperfusion injury of ischemic erectile tissue associated with reactive oxygen species (ROS) and the potential role of ROS scavengers in the clinical therapy of ischemic priapism.. Anesthetized adult New Zealand white male rabbits (n = 7) were exposed to a low oxygen tension breathing gas to achieve hypoxia within the corpora cavernosa. This resulted in a mean systemic oxygen saturation of 60%. The pelvic nerve was electrically stimulated to induce penile erection, and the base of the erect penis was clamped. After varying durations of ischemia, the clamp was removed to allow reperfusion. We determined the intracavernosal oxygen tension, histologic changes, myeloperoxidase activity, and lipid peroxidation.. Corporal partial pressure of oxygen progressively decreased as the duration of priapism increased. A statistically significant increase was noted in myeloperoxidase activity and lipid peroxidation with corporal reperfusion. Polymorphonuclear leukocyte infiltration was documented in the ischemic reperfused tissue.. In the management of ischemic priapism, reperfusion causes erectile tissue injury owing to the presence of ROS. There is a need to investigate the utility of ROS scavengers and antioxidants in the management of ischemic priapism.

Topics: Animals; Chemotaxis, Leukocyte; Hypoxia; Ischemia; Lipid Peroxidation; Male; Models, Animal; Neutrophils; Oxidative Stress; Penis; Peroxidase; Priapism; Rabbits; Reactive Oxygen Species; Reperfusion Injury

Gut ischemia-reperfusion (I/R) injury is a serious complication of shock. Previously we demonstrated that the administration of alpha-melanocyte-stimulating hormone (MSH) immediately before mesenteric I/R protected against postischemic gut injury. In this report, we tested the therapeutic efficacy of alpha-MSH on gut I/R (60 min ischemia, 6 h reperfusion) injury when given at different time points of reperfusion. Rats underwent sham surgery or were treated with saline or with alpha-MSH that was given 1, 2, or 4 h after superior mesenteric artery clamping. Vehicle-treated I/R rats exhibited severe mucosal injury and increased NF-kappaB DNA binding activity, myeloperoxidase (MPO) activity, and interleukin-6 and heme oxygenase-1 (HO-1) expression. In contrast, rats given alpha-MSH at 1 h of reperfusion, but not 2 h or 4 h, exhibited much less mucosal injury. Rats given alpha-MSH at 1 h or 2 h of reperfusion, but not 4 h, exhibited less MPO activity, NF-kappaB DNA binding activity, and interleukin-6 protein and even higher levels of heme oxygenase-1 than vehicle-treated rats. In addition, we found that combined use of alpha-MSH, a known inhibitor of IkappaBalpha tyrosine phosphorylation, with BAY 11-7085, an inhibitor of IkappaBalpha Ser 32,36 phosphorylation, abrogates gut MPO induction and tissue injury at early and late time points of reperfusion. Thus, alpha-MSH, an endogenous peptide with a favorable side-effect profile, is effective in treating experimental gut I/R injury when given early after the initial ischemia and may represent a candidate therapy for gut I/R in humans in whom recognition and treatment are often delayed.

Topics: alpha-MSH; Animals; Anti-Infective Agents; Blotting, Western; DNA; Drug Therapy, Combination; Electrophoretic Mobility Shift Assay; Heme Oxygenase (Decyclizing); Heme Oxygenase-1; Ileum; Interleukin-6; Male; NF-kappa B; Nitriles; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sulfones

The effect of hyperbaric oxygen is known to increase survival of ischemic tissue but its mechanism is not fully understood. The purpose of this study was to evaluate the effect of hyperbaric oxygen on a rat musculocutaneous flap versus ischemia-reperfusion injury, focusing on the mechanism involving the expression of adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) of endothelial cells and CD18 of neutrophils. A transverse rectus abdominis musculocutaneous (TRAM) flap (6 x 5 cm) supplied by a single superior epigastric vascular pedicle was elevated in 100 Sprague-Dawley rats. The rats were divided into 4 groups: group 0, sham (n = 10); group I, 4 hours of ischemia followed by reperfusion (n = 30); group II, 4 hours of ischemia and hyperbaric oxygen (100% oxygen, 2.5 atm absolute, during the last 90 minutes of ischemia before reperfusion) followed by reperfusion (n = 30); and group III, 4 hours of ischemia followed by reperfusion and hyperbaric oxygen (100% oxygen, 2.5 atm absolute, after reperfusion for 90 minutes; n = 30). The study consisted of gross examination for flap survival, histology, immunohistochemical staining, myeloperoxidase assay, flow cytometric study of CD18, and Northern blot analysis on ICAM-1 messenger ribonucleic acid expression. Gross measurement of the flap showed increased survival in groups II and III compared with group I (P < 0.05). The leukocytes adherent to the endothelium were counted at 24 hours and on day 5. Group I leukocytes were significantly increased compared with groups II and III (P < 0.05). The myeloperoxidase assay of TRAM flaps at 24 hours revealed a significant increase in group I compared with groups II and III (P < 0.05). The expression of CD18 was similar between groups I, II, and III. Immunohistochemical staining for ICAM-1 and Northern blot analysis on ICAM-1 messenger ribonucleic acid showed decreased expression in groups II and III compared with group I. Throughout the analysis, groups II and III did not show any significant differences. These results suggests that hyperbaric oxygen reduces the accumulation of leukocytes in the TRAM flap, but not enough to prevent adhesion of neutrophils on endothelial cells; ischemia-reperfusion injury increases the expression of CD18 and ICAM-1 and causes increased adhesion of leukocytes on the endothelium; hyperbaric oxygen does not alter the expression of CD18 but decreases the expression of ICAM-1; and the point of application for hyperbaric oxyge

Topics: Animals; CD18 Antigens; Cell Adhesion; Endothelium, Vascular; Graft Survival; Hyperbaric Oxygenation; Immunohistochemistry; Intercellular Adhesion Molecule-1; Leukocytes; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Surgical Flaps

The aim of this study was to evaluate the effect of allopurinol, methylene blue, and a monoclonal antibody to the adhesion molecule ICAM-1 in intestinal ischemia and reperfusion injury.. The rats were divided into 5 groups. CG (n = 8) was untreated controls, SISG (n = 11) received sterile isotonic saline solution, ICAMG (n = 12) received a monoclonal antibody to rat ICAM-1, ALLOG (n = 12) received allopurinol, and MBG (n = 14) received methylene blue. Intestinal ischemia was performed for 60 minutes followed by 60 minutes of reperfusion. The agents were injected 10 minutes before the reperfusion to animals. After 60 minutes of reperfusion, the plasma samples for myeloperoxidase (MPO) activity, tumor necrosis factor alpha (TNF-alpha) and uric acid levels, and the intestinal biopsies of ileum and jejunum for histopathologic examination were taken.. The mucosal damage was attenuated, and TNF-alpha level significantly decreased in ALLOG and ICAMG compared with SISG. The MPO activity was the lowest in ICAMG, and uric acid level was significantly decreased in ALLOG compared with the other groups. Methylene blue decreased TNF-alpha response to reperfusion injury but significantly increased the grade of the mucosal damage and the MPO activity.. This study shows that prereperfusion application of allopurinol and monoclonal antibody to the adhesion molecule ICAM-1 may attenuate the damage caused by intestinal ischemia and reperfusion, but the different time-points for application, the effects observed in the different ischemia and reperfusion durations, and the long-term results also should be investigated in the same experimental model before the final conclusion. Methylene blue was not effective to prevent or attenuate the intestinal tissue injury, but because this was the first study examining the effect of methylene blue on intestinal reperfusion injury, further studies with the different doses, ischemic duration, and application times will be needed.

Topics: Allopurinol; Animals; Antibodies, Monoclonal; Drug Evaluation, Preclinical; Ileum; Intercellular Adhesion Molecule-1; Intestines; Ischemia; Jejunum; Male; Methylene Blue; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha; Uric Acid

To investigate the effect of liposome-carried metallothionein (lipo-MT) on secondary ischemia-reperfusion injury in the rat island flap.. An abdominal island flap was created in the Wistar rat. The animals were divided into four groups: the sham group, the secondary ischemia-reperfusion group, the group treated with blank liposome and the group treated with lipo-MT. The malondialdehyde (MDA) content, the myeloperoxidase (MPO) activity was assayed immediately, at 30 minutes and 7 days after the secondary venous ischemia-reperfusion. The level of endothelin (ET) and lactic dehydrogenase (LDH) of the rat plasma was measured at 30 minutes after secondary venous ischemia-reperfusion. The content of MT of the flap was assayed by Cd-hemoglobin saturation method at 7 days after the operation.. The treatment of lipo-MT significantly decreased the content of MDA, MPO of the flap, decreased the activity of ET, LDH of the rat palsma, increased the content of MT of the flap and improved the flap viability.. Lipo-MT can improve flap survival by reducing ischemia-reperfusion injury.

Topics: Animals; Endothelins; Graft Survival; Ischemia; Lactate Dehydrogenases; Liposomes; Malondialdehyde; Metallothionein; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Surgical Flaps; Time Factors

To investigate the effects of carbachol on local inflammation in gut tissue during ischemia/reperfusion (I/R).. A jejunal sac was formed in Wistar rats. The superior mesenteric artery was occluded (SMAO) for 60 minutes followed by reperfusion for another 60 minutes. Animals were divided into three groups, pretreatment group (carbachol was injected into the jejunal sac 30 minutes after SMAO, 0.1 mg/kg), treatment group (carbachol was injected in same dosage into the jejunal sac 30 minutes after reperfusion), and controls (saline injection). The contents of tumor necrosis factor-alpha(TNF-alpha) and activity of myeloperoxidase (MPO) in gut tissue were determined at 1 hours, 2.5 hours and 6 hours after SMAO.. The contents of TNF-alpha and activity of MPO were significantly decreased in pretreatment and treatment groups compared with control group at 2.5 hours after SMAO (both P<0.05). There were no differences in both contents between pretreatment group and treatment group at any specified time. It was also found that there were less inflammatory pathological changes in the gut tissues in the two treated groups than that of control.. The RESULTS suggest that carbachol could alleviate gut inflammatory response during gut ischemia/reperfusion injury by inhibiting proinflammatory cytokine release.

Topics: Animals; Carbachol; Gastroenteritis; Intestines; Ischemia; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Tumor Necrosis Factor-alpha

Matrix metalloproteinase-9 (MMP-9) activity increases in the brain during the first day after focal ischemia and might be involved in the pathogenesis of tissue damage. We previously showed MMP-9 in the extracellular space of brain parenchyma along with neutrophil recruitment after ischemia. In the present study, we tested whether neutrophils were a direct source of enhanced MMP-9 in the ischemic brain. Neutrophil infiltration was prevented either by injecting an antibody against ICAM-1, which abrogates neutrophil adhesion to the endothelial vessel wall, or by inducing neutropenia. One-hour intraluminal middle cerebral artery occlusion with reperfusion was induced, and studies were performed at 24 hours. Circulating neutrophils expressed 95-kDa MMP-9 and dimers, and infiltrated neutrophils stained positive for MMP-9. The expression of MMP-9 (mainly 95-kDa proform and dimers and, to a lesser extent, 88-kDa form) increased in brain after ischemia/reperfusion. Treatments preventing neutrophil infiltration failed to preclude the ischemia-induced increase in 88-kDa MMP-9 form and gelatinase activity in neurons and blood vessels. However, these treatments prevented the major increase in 95-kDa MMP-9 form and dimers. We conclude that neutrophil infiltration highly contributes to enhanced MMP-9 in the ischemic brain by releasing MMP-9 proform, which might participate in the tissular inflammatory reaction.

Topics: Animals; Antibodies, Monoclonal; Cell Movement; Dimerization; Gelatinases; Infarction, Middle Cerebral Artery; Intercellular Adhesion Molecule-1; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Neurons; Neutropenia; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Complement activation contributes to ischemia and reperfusion (IR)-initiated organ injury. C1 inhibitor (C1 Inh) inhibits the earliest steps of the classical and the mannose binding lectin pathways.. To determine whether C1 Inh prevented tissue injury, we performed intestinal IR experiments in BALB/c and C57BL/6 mice.. We found that C1 Inh limits mucosal injury in the two strains in a dose dependent manner. Tissue damage was associated with the accumulation of functional polymorphonuclear cells, which was reduced following C1 Inh treatment. Constitutive nitric oxide synthase activity correlated with the development of injury in the C57BL/6 but not in the BALB/c mouse.. These findings emphasize the importance of complement activation in ischemia/reperfusion and highlight the potential therapeutic use of C1 Inh in limiting or preventing damage caused by IR.

Topics: Animals; Complement Activation; Complement C1 Inactivator Proteins; Complement C3; Eicosanoids; Humans; Intestinal Mucosa; Intestines; Male; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Myenteric Plexus; Neutrophils; Nitric Oxide Synthase; Peroxidase; Reperfusion Injury; Splanchnic Circulation

Acutely increased intra-abdominal pressure (IAP) may lead to abdominal compartment syndrome (ACS), which ischaemia/reperfusion (I/R) injury plays an important role. The main goal of the management of ACS is to lower the intra-abdominal pressure despite reperfusion injury. Octreotide (OCT), a synthetic somatostatin analogue, lowers the splanchnic perfusion. The aim of this study was to investigate whether OCT improves the reperfusion injury after decompression of acute abdominal hypertension.Under anesthesia, a catheter was inserted intraperitoneally and using an aneroid manometer connected to the catheter, IAP was kept at 20 mmHg (ischemia group; I) for 1h. In the I/R group, pressure applied for an hour was decompressed and 1h reperfusion period was allowed. In another group of I/R, OCT was administered (50 microg/kg i.p.) immediately before the decompression of IAP. The results demonstrate that kidney and lung tissues of malondialdehyde (MDA; an end product of lipid peroxidation) levels and myeloperoxidase (MPO; index of tissue neutrophil infiltration) activity were elevated, while glutathione (GSH; a key to antioxidant) levels were reduced in I/R group (P<0.001). Moreover, OCT treatment applied in the I/R group reduced the elevations in blood urea nitrogen (BUN) and serum creatinine levels. Our results implicate that IAP causes oxidative organ damage and OCT, by reducing splanchnic perfusion and controlling the reperfusion of abdominal organs, could improve the reperfusion-induced oxidative damage. Therefore, its therapeutic role as a "reperfusion injury-limiting" agent must be further elucidated in IAP-induced abdominal organ injury.

Topics: Abdomen; Acute Disease; Animals; Female; Glutathione; Hypertension; Kidney; Lipid Peroxidation; Lung; Male; Malondialdehyde; Octreotide; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Renal ischemia/reperfusion injury could arise as a consequence of clinical conditions such as renal transplantation, shock, cardiac arrest, hemorrhage and renal artery surgery. In this experimental study, we aimed to determine the preventive effects of amrinone on bilateral renal ischemia/reperfusion injury in rats. A total of 60 Wistar-albino rats were divided into six groups ( n=10). Midline laparotomies were made under ketamine anesthesia. In the sham, amrinone1 and amrinone2 without ischemia (AWI1 and AWI2) groups saline, 5 and 10 mg/kg of amrinone was infused, respectively. In the ischemia, ischemia plus amrinone1 (IPA1) and ischemia plus amrinone2 (IPA2) groups, saline and 5 and 10 mg/kg of amrinone was infused, respectively, at the beginning of reperfusion, subsequent to 45 min of bilateral renal artery occlusion. Following 6 h of reperfusion, blood was drawn to study serum BUN and creatinine and a bilateral nephrectomy was done to determine tissue malonyldialdehyde ( MDA) and myeloperoxidase (MPO) levels. The results were analysed by Mann-Whitney U-test. The parameters studied were statistically higher in the ischemia group compared with the other groups ( P<0.05 for each comparison), indicating renal I/R injury. These parameters were lower in the amrinone without ischemia groups (AWI1 and AWI2) than in the sham group, however there were no significant differences between the groups ( P>0.05, for each comparison). The treatment groups IPA1 and IPA2 had statistically similar results compared with the sham group, showing the preventive effect of amrinone on renal I/R injury at the given doses. We conclude that amrinone prevented experimental renal ischemia/reperfusion injury in rats, independently of the administered doses. This preventive effect of the agent could depend on its effect of regulating the microcirculation, in decreasing intracellular calcium and in preventing neutrophil activation. We propose that this preventive effect of amrinone - which has gained clinical application especially in cases of cardiac insufficiency - could also be exploited in clinical conditions related with renal ischemia/reperfusion.

Topics: Amrinone; Animals; Blood Urea Nitrogen; Creatinine; Dose-Response Relationship, Drug; Ischemia; Isomerism; Malondialdehyde; Peroxidase; Phosphodiesterase Inhibitors; Rats; Rats, Wistar; Renal Circulation; Reperfusion Injury

99mTc-RP517 is a new leukotriene B4 (LTB4) receptor antagonist developed for imaging acute inflammation or infection. A unique property of 99mTc-RP517 is its ability to label white blood cells in vivo after intravenous injection. The goals of this study were to determine relative 99mTc-RP517 binding to human leukocyte subtypes and the 99mTc-RP517 uptake pattern in canine myocardium where inflammation was induced by either coronary occlusion and reperfusion or tumor necrosis factor alpha (TNFalpha) injection.. Fluorescence-activated cell sorter analysis was performed on whole human blood (n=2) and isolated neutrophils (n= 4) with a fluorescent analog of 99mTc-RP517, [F]-RP517. In whole blood, [F]-RP517 (500 nmol/L) preferentially labeled neutrophils. On isolated neutrophils, [F]-RP517 (10 nmol/L) binding was inhibited by 44% when LTB4 (400 nmol/L) was added. 99mTc-RP517 was injected intravenously in anesthetized, open-chest dogs before coronary occlusion (90 minutes) and reperfusion (120 minutes) (n=9) or before intramyocardial TNFalpha injection (n=3). Ex vivo images of heart slices were acquired. The left ventricle was divided into 72 segments for flow and 99mTc-RP517 uptake analysis. There was an inverse exponential relationship between 99mTc-RP517 uptake and occlusion flow (r=0.73). In the same 15 segments, 99mTc-RP517 uptake was highly correlated with the neutrophil enzyme myeloperoxidase (r=0.91). Ex vivo images revealed tracer uptake in the reperfused area (ischemic to normal count ratio=2.7+/-0.2).. RP517 binds to the neutrophil LTB4 receptor after intravenous injection. After reperfusion, 99mTc-RP517 uptake correlated with myeloperoxidase and was observed on ex vivo images, indicating that this tracer may have potential as an inflammation-imaging agent.

Topics: Animals; Autoradiography; Binding, Competitive; Coronary Circulation; Coronary Disease; Dogs; Drug Administration Routes; Flow Cytometry; Hemodynamics; Humans; Inflammation; Injections; Injections, Intravenous; Myocardial Reperfusion; Myocarditis; Myocardium; Neutrophils; Organotechnetium Compounds; Peroxidase; Predictive Value of Tests; Receptors, Leukotriene B4; Reperfusion Injury; Tumor Necrosis Factor-alpha

The role of P-selectin in the process of reperfusion injury was evaluated using a recombinant soluble P-selectin glycoprotein ligand-Ig (rPSGL-Ig) in a canine coronary artery balloon occlusion model. rPSGL-Ig (1 mg/kg) or saline was given as an intravenous bolus 15 min before balloon deflation. Balloon occlusion time was 90 min followed by either 120 min or 7 days reperfusion. Infarct size was significantly reduced in the treatment group when expressed either as percentage of the area at risk or as absolute infarct size. Histological analysis showed that extensive myocardial injury and neutrophil infiltration were reduced by rPSGL-Ig. Myeloperoxidase activity (MPO) was significantly reduced in the risk area in the rPSGL-Ig group. Left ventricular ejection fraction was significantly less impaired during the first 24 h after reperfusion in the rPSGL-Ig group, although there was no difference by 7-day follow-up. Thus, administration of rPSGL-Ig decreases myocardial injury and inflammatory response for at least 7 days after reperfusion of ischemic myocardium.

Topics: Animals; Disease Models, Animal; Dogs; Follow-Up Studies; Membrane Glycoproteins; Myocardial Infarction; P-Selectin; Peroxidase; Recombinant Proteins; Reperfusion Injury; Stroke Volume; Time Factors

Hepatic steatosis is a major risk factor in ischemia-reperfusion. The present study evaluates whether preconditioning, demonstrated to be effective in normal livers, could also confer protection in the presence of steatosis and investigates the potential underlying protective mechanisms. Fatty rats had increased hepatic injury and decreased survival after 60 minutes of ischemia compared with lean rats. Fatty livers showed a degree of neutrophil accumulation and microcirculatory alterations similar to that of normal livers. However, in presence of steatosis, an increased lipid peroxidation that could be reduced with glutathione-ester pretreatment was observed after hepatic reperfusion. Ischemic preconditioning reduced hepatic injury and increased animal survival. Both in normal and fatty livers, this endogenous protective mechanism was found to control lipid peroxidation, hepatic microcirculation failure, and neutrophil accumulation, reducing the subsequent hepatic injury. These beneficial effects could be mediated by nitric oxide, because the inhibition of nitric oxide synthesis and nitric oxide donor pretreatment abolished and simulated, respectively, the benefits of preconditioning. Thus, ischemic preconditioning could be an effective surgical strategy to reduce the hepatic ischemia-reperfusion injury in normal and fatty livers under normothermic conditions, including hepatic resections, and liver transplantation.

Topics: Animals; Fatty Liver; Ischemic Preconditioning; Lipid Peroxidation; Liver; Male; Malondialdehyde; Peroxidase; Rats; Rats, Zucker; Reperfusion Injury

The aim of this study was to investigate the role of inducible nitric oxide (NO) synthase (iNOS) and NO on the modulation of the inflammatory response caused by splanchnic ischemia and reperfusion. A severe model of mesenteric ischemia and reperfusion was produced by subjecting mice to 45 min occlusion followed by reperfusion of the superior mesenteric artery and celiac trunk. In this experimental protocol, wild-type mice treated with GW274150 (5 mg/kg i.p.), a novel, potent, and selective inhibitor of iNOS activity, and mice lacking of the gene for iNOS (iNOS 'knock-out', iNOS-KO) exhibited no difference in the rate of mortality in comparison with wild-type control mice. In a second study, using a less severe model of mesenteric injury obtained by occlusion of the superior mesenteric artery only for 45 min, we evaluated the survival rate. Under these conditions, wild-type mice treated with GW274150 and iNOS-KO mice showed a significant difference in the rate of mortality in comparison with wild-type. Therefore, wild-type mice treated with GW274150 and iNOS-KO mice when compared with wild-type littermates showed a significant reduction of the mesenteric injury, upregulation of P-selectin and intercellular adhesion molecule-1, and neutrophil infiltration, as well as a significant inhibition of the degree of oxidative and nitrosative damage, indicated by malondialdehyde levels, formation of nitrotyrosine and poly(ADP-ribose)polymerase (PARP), respectively. Plasma levels of the proinflammatory cytokines tumour necrosis factor-alpha, interleukin (IL) 6, and IL-1beta were also significantly reduced in iNOS-KO mice in comparison with control wild-type mice. Wild-type mice treated with GW274150 and iNOS-KO mice were also found to have reduced activation of the transcriptional factor nuclear factor-kappaB in the ileum. These results suggest that the induction of iNOS and NO production are essential for the upregulation of the inflammatory response in splanchnic ischemia/reperfusion and participate in end organ damage under these conditions.

Topics: Animals; Cytokines; Disease Models, Animal; Immunohistochemistry; Inflammation Mediators; Ischemia; Lipid Peroxidation; Male; Malondialdehyde; Mesenteric Arteries; Mesenteric Vascular Occlusion; Mice; Mice, Knockout; Neutrophil Infiltration; Nitric Oxide; Nitric Oxide Synthase; P-Selectin; Peroxidase; Reperfusion Injury; Sensitivity and Specificity; Survival Rate

Multiple gene transfer might permit modulation of concurrent biochemical pathways involved in lung graft ischemia-reperfusion injury. In this study we analyzed whether recipient intramuscular naked plasmid cotransfection of transforming growth factor beta(1) and interleukin 10 would result in amelioration of lung graft ischemia-reperfusion injury.. Forty-eight hours before transplantation, 6 groups (n = 6) of F344 rats received intramuscular injection of naked plasmid encoding chloramphenicol acetyltransferase, chloramphenicol acetyltransferase plus beta-galactosidase, transforming growth factor beta(1), interleukin 10, or transforming growth factor beta(1) plus interleukin 10 or were not treated. Donor lungs were flushed and stored for 18 hours at 4 degrees C before transplantation. Twenty-four hours later, grafts were assessed immediately before the animals were killed. Arterial oxygenation, wet/dry ratio, myeloperoxidase, and proinflammatory cytokines (interleukin 1, tumor necrosis factor alpha, interferon gamma, and interleukin 2) were measured, and immunohistochemistry was performed.. For lung graft function, the arterial oxygenation was considerably higher in the cotransfected group receiving transforming growth factor beta(1) plus interleukin 10 compared with that in all other groups (P < or =.03). The wet/dry ratio, reflecting lung edema, was reduced in the cotransfected group compared with that in control animals (nontreated, P <.02; chloramphenicol acetyltransferase, P <.03; chloramphenicol acetyltransferase plus beta-galactosidase, P <.01). Myeloperoxidase, which measures neutrophil sequestration, was also reduced with cotransfection compared with that seen in control animals (P < or =.03). All proinflammatory cytokines were decreased in the cotransfected group compared with those in all other groups (interleukin 1beta, P <.04; tumor necrosis factor alpha, P <.002; interferon gamma, P <.0001; interleukin 2, P <.03). These results indicate that cotransfection provides a synergistic benefit in graft function versus either cytokine alone, neutrophil sequestration, or inflammatory cytokine expression. Immunohistochemistry showed positive staining of transforming growth factor beta(1) plus interleukin 10 in type I and II pneumocytes and localized edema fluid.. Recipient intramuscular naked plasmid cotransfection of transforming growth factor beta(1) and interleukin 10 provides a synergistic effect in ameliorating lung reperfusion injury after prolonged ischemia.

Topics: Analysis of Variance; Animals; Cytokines; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Gene Expression; Gene Transfer Techniques; Immunohistochemistry; Interleukin-10; Lung; Lung Transplantation; Male; Peroxidase; Plasmids; Rats; Rats, Inbred F344; Reperfusion Injury; Transfection; Transforming Growth Factor beta

We have shown that the orally administered cyanidin 3-O-beta-D-glucoside (C3G) attenuates the hepatic ischemia-reperfusion (I/R) injury, which was used as a model for oxidative stress through a decrease in neutrophil chemoattractant production in rats. The rats were subjected to hepatic I/R at 30 min after the administration of C3G (0.9 mmol/kg body weight) or vehicle. I/R treatment resulted in the elevation of oxidative stress marker [liver thiobarbituric acid-reactive substance, Nepsilon-(hexanonyl) lysine and dityrosine] levels in the liver and of the serum activities of marker enzymes for liver injury. The administration of C3G significantly suppressed these elevations, which had been caused by hepatic I/R. Liver myeloperoxidase activity, a useful marker for neutrophil infiltration into tissues, and the plasma and liver concentration of cytokine-induced neutrophil chemoattractant-1 (CINC-1), which has a potent chemotactic activity, were markedly elevated in the control group after hepatic I/R. However, these elevations were significantly suppressed in the C3G group. C3G and its metabolites in the plasma and liver were detected in the C3G group after hepatic I/R. These results suggest that the absorbed C3G and/or its metabolites can act as antioxidants in the blood and liver and scavenge the reactive oxygen species, and brought on a decrease in neutrophil infiltration into the liver through the suppression of CINC-1 production and the tissue damage caused by neutrophils after I/R is attenuated.

Topics: Animals; Anthocyanins; Antioxidants; Biomarkers; Chemotactic Factors; Glucosides; Liver; Male; Neutrophils; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Thiobarbituric Acid Reactive Substances

Topics: Animals; Fingolimod Hydrochloride; Immunosuppressive Agents; Liver; Liver Circulation; Lymphocyte Count; Peroxidase; Propylene Glycols; Rats; Rats, Inbred Lew; Reperfusion Injury; Sphingosine

We examined the effects of early blockade of CD62 selectin-mediated adhesive interactions in steatotic rat liver models of ex vivo cold ischemia followed by reperfusion or transplantation by administration of P-selectin glycoprotein ligand-1 (rPSGL-Ig). In the model of cold ischemia/reperfusion, livers pretreated ex vivo with rPSGL-Ig at harvesting from obese Zucker rats showed significantly decreased portal resistance, increased bile production, and diminished hepatic endothelial neutrophil infiltration, as compared with untreated controls. Pretreatment of fatty livers with rPSGL-Ig prior to transplantation extended the survival of lean Zucker rat recipients from 40% to 90%. This effect correlated with significantly improved liver function, depressed neutrophil activity, and decreased histologic features of hepatocyte injury. Intragraft expression of CD62 P-selectin was similar in both recipient groups. rPSGL-Ig treatment decreased intragraft infiltration by CD3/CD25 cells, diminished expression of pro-inflammatory TNFalpha, IL-6, iNOS, IL-2 and IFN-gamma, without significantly affecting mRNA levels coding for anti-inflammatory IL-4. Thus, rPSGL-Ig blockade of CD62-mediated adhesive interactions protects against severe ischemia/reperfusion injury suffered otherwise by steatotic rat livers. These findings document the potential utility of rPSGL-Ig in increasing the transplant donor pool through modulation of marginal steatotic livers.

Topics: Animals; Cytokines; Graft Survival; Liver; Liver Transplantation; Male; Membrane Glycoproteins; Organ Preservation; P-Selectin; Peroxidase; Rats; Rats, Zucker; Reperfusion Injury; Steatitis; Time Factors; Transplantation, Homologous

The preventive effect of Hwangryun-Hae-Dok-tang (HHDT, Huanglian-Jie-Du-Tang), a Chinese herbal medicine, and its ingredients on ischemia/reperfusion-induced brain injury was evaluated in the rat brain. HHDT consists of four herbs, namely, Coptidis rhizoma, Scutellariae radix, Phellodendri cortex, and Gardeniae fructus. Ischemia was induced by intraluminal occlusion of the right middle cerebral artery for 120 min and reperfusion was continued for 22 h. HHDT (200 mg/kg), Coptidis rhizoma (100 mg/kg), Scutellariae radix (100 mg/kg), Phellodendri cortex (100 mg/kg), and Gardeniae fructus (100 mg/kg) were orally administered, promptly prior to reperfusion and 2 h after reperfusion. Baicalein, a component of Scutellariae radix, was also examined at a dosage of 50 mg/kg given 2 h apart, promptly prior to and 2 h after reperfusion. Total infarction volume in the ipsilateral hemisphere of ischemia/reperfusion rats was significantly lowered by treatment with HHDT, Scutellariae radix, and balicalein. However, the other ingredient of HHDT did not show any ameliorating effects on total infarction volume. The inhibiting effect of Scutellariae radix on total infarction volume was much higher than that of the others. In addition, HHDT, Scutellariae radix, and baicalein significantly inhibited myeloperoxidase (MPO) activity, an index of neutrophil infiltration in ischemic brain tissue at about the same rate (30%). There was marked mismatch between total infarction volume and MPO activity in the Scutellariae radix-treated rats but not in the HHDT- and baicalein-treated groups. Our findings suggest that Scutellariae radix as an ingredient of HHDT plays a crucial protective role in ischemia-induced brain injury. In addition, it is apparent that the effect of Scutellariae radix is the result, in part, of baicalein, a compound contained in Scutellariae radix.

Topics: Animals; Blood Cell Count; Brain Ischemia; Cell Death; Drugs, Chinese Herbal; Flavanones; Flavonoids; Free Radical Scavengers; Hippocampus; Infarction, Middle Cerebral Artery; Ischemic Attack, Transient; Male; Neurons; Neuroprotective Agents; Neutrophil Infiltration; Peroxidase; Phytotherapy; Plant Extracts; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Testicular artery occlusion causes an enhanced formation of reactive oxygen species, which contributes to the pathophysiology of tissue damage. Here, we have investigated the effects of caffeic acid phenethyl ester (CAPE), a new antioxidant and antiinflammatory agent, in rats subjected to testicular torsion/detorsion (T/D). Thirty-five male rats were divided into four groups: sham operation group ( n=8), torsion group ( n=9), T/D+saline group ( n=9) and T/D+CAPE group ( n=9). Rats, except the sham operation group, were subjected to left unilateral torsion (720 degrees rotation in the clockwise direction) without including the epididymis. After torsion (2 h) and detorsion (4 h) periods, rats were sacrificed and bilateral orchidectomy was performed. Testis tissues were washed with cold saline solution, cut into small pieces with scissors, placed into glass bottles and homogenised in four volumes of ice-cold Tris-HCl buffer. Clear supernatant fluid was used for biochemical analyses. Treating rats with CAPE (applied at 10 micro mol/kg, 30 min prior to T/D) attenuated the testicular injury, as well as the increase in the tissue levels of myeloperoxidase and thiobarbituric acid-reactant substances (TBARS) caused by T/D in the testis. Testis tissues showed a significant increase in glutathione peroxidase (GSH-Px) activity compared to the torsion group when CAPE was applied. Taken together, our results clearly demonstrate that CAPE treatment exerts a protective effect on testicular T/D, and part of this effect may be due to inhibiting the neutrophil-mediated cellular injury.

Topics: Animals; Caffeic Acids; Catalase; Disease Models, Animal; Glutathione Peroxidase; Male; Peroxidase; Phenylethyl Alcohol; Protective Agents; Rats; Reperfusion Injury; Spermatic Cord Torsion; Superoxide Dismutase; Testis; Thiobarbituric Acid Reactive Substances

These experiments were designed to determine whether green tea extract (GTE), which contains polyphenolic free radical scavengers, prevents ischemia-reperfusion injury to the liver. Rats were fed a powdered diet containing 0-0.3% GTE starting 5 days before hepatic warm ischemia and reperfusion. Free radicals in bile were trapped with the spin-trapping reagent alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone (4-POBN) and measured using electron spin resonance spectroscopy. Hepatic ischemia-reperfusion increased transaminase release and caused pathological changes including focal necrosis and hepatic leukocyte infiltration in the liver. Transaminase release was diminished by over 85% and pathological changes were almost totally blocked by 0.1% dietary GTE. Ischemia-reperfusion increased 4-POBN/radical adducts in bile nearly twofold, an effect largely blocked by GTE. Epicatechin, one of the major green tea polyphenols, gave similar protection as GTE. In addition, hepatic ischemia-reperfusion activated NF-kappa B and increased TNF-alpha mRNA and protein expression. These effects were all blocked by GTE. Taken together, these results demonstrate that GTE scavenges free radicals in the liver after ischemiareoxygenation, thus preventing formation of toxic cytokines. Therefore, GTE could prove to be effective in decreasing hepatic injury in disease states where ischemia-reperfusion occurs.

Topics: Animals; Aspartate Aminotransferases; Bile; Catechin; Electron Spin Resonance Spectroscopy; Flavonoids; Free Radical Scavengers; Free Radicals; Leukocytes; Liver; Male; Necrosis; NF-kappa B; Nitrogen Oxides; Oxidative Stress; Peroxidase; Phenols; Plant Extracts; Polymers; Pyridines; Rats; Rats, Sprague-Dawley; Reperfusion Injury; RNA, Messenger; Tea; Tumor Necrosis Factor-alpha

We sought to investigate whether raloxifene reduces ischemia-reperfusion injury and what mechanisms are involved in the cardioprotective effects.. Estradiol-17-beta reduces myocardial infarct size in ischemia-reperfusion injury. Raloxifene, a selective estrogen receptor modulator, demonstrates immediate coronary artery vasorelaxing effects.. The myocardial ischemia-reperfusion model included anesthetized open-chest dogs after 90-min occlusion of the left anterior descending coronary artery (LAD) and subsequent 6-h reperfusion. Raloxifene and/or other drugs were infused into the LAD from 10 min before coronary occlusion to 1 h after reperfusion without an occlusion period.. Infarct size was reduced in the raloxifene (5 microg/kg per min) group compared with the control group (7.2 +/- 2.5% vs. 40.9 +/- 3.9% of the area at risk, p < 0.01). Either N(G)-nitro-L-arginine methyl ester (L-NAME), the inhibitor of nitric oxide (NO) synthase, or charybdotoxin, the blocker of Ca(2+)-activated K+ (K(Ca)) channels, partially attenuated the infarct size-limiting effect, and both of them completely abolished the effect. The incidence of ventricular fibrillation was also less in the raloxifene group than in the control group (11% vs. 44%, p < 0.05). Activity of p38 mitogen-activated protein (MAP) kinase increased with 15-min ischemia, and raloxifene pretreatment inhibited the activity. Myeloperoxidase activity of the 6-h reperfused myocardium was also attenuated by raloxifene.. These data demonstrate that raloxifene reduces myocardial ischemia-reperfusion injury by mechanisms dependent on NO and the opening of K(Ca) channels in canine hearts. Deactivation of p38 MAP kinase and myeloperoxidase by raloxifene may be involved in the cellular mechanisms of cardioprotection.

Topics: Animals; Charybdotoxin; Dogs; Enzyme Inhibitors; Mitogen-Activated Protein Kinase Kinases; NG-Nitroarginine Methyl Ester; Nitric Oxide Synthase; Peroxidase; Potassium Channels, Calcium-Activated; Raloxifene Hydrochloride; Reperfusion Injury; Selective Estrogen Receptor Modulators

Peroxynitrite is assumed to play a crucial role in brain damage associated with the overproduction of nitric oxide (NO). The purpose of this study is to examine time-dependent changes of nitrite and nitrate (NOx) concentration in the circulation, and peroxynitrite formation as well as the expression of inducible nitric oxide synthase (iNOS) in the penumbra of rat brains during transient middle cerebral artery occlusion (MCAO) of Wistar rat for 2 h and reperfusion for 4-70 h. NOx concentration in the circulation was continuously monitored at the right jugular vein by microdialysis. The expression of iNOS was detected at 22-70 h after reperfusion in vascular walls and the cortex. Nitrotyrosine, a marker of peroxynitrite, appeared 4 h after reperfusion in the cortex, increasing substantially at 22-46 h in vascular walls. NOx level in dialysate increased immediately after MCAO. After a gradual decrease, the level increased again 4 h after reperfusion, reaching a maximum at 46 h. Brain myeloperoxidase activity, a marker of neutrophil infiltration, was not detected 4 h after reperfusion, but greatly increased at 22 h and then decreased. These results suggest that a marked increase of NOx level in the circulation might reflect the expression of iNOS, while neuronal NOS may contribute to peroxynitrite formation in the cortex observed at an earlier phase of reperfusion. This study indicates that monitoring NOx level in the circulation serves to assess the progress of stroke, and to determine appropriate therapeutic measures.

Topics: Animals; Cerebral Cortex; Cerebral Infarction; Cerebrovascular Circulation; Chemotaxis, Leukocyte; Disease Models, Animal; Hypoxia-Ischemia, Brain; Infarction, Middle Cerebral Artery; Male; Neutrophils; Nitric Oxide; Nitric Oxide Synthase; Peroxidase; Peroxynitrous Acid; Rats; Rats, Wistar; Reaction Time; Reperfusion Injury; Tyrosine

The aim of this study was to investigate whether in vivo administration of a low, sub-lethal dose of lipoteichoic acid (LTA), a bacterial wall-fragment derived from the Gram-positive bacterium Staphylococcus aureus, protects the kidney against the renal dysfunction and injury caused by ischemia/reperfusion (I/R).. Male Wistar rats were administered LTA from S. aureus (1 mg/kg, IP). After 24 hours, rats were subjected to bilateral renal ischemia (45 min) followed by reperfusion (6 h). Serum and urinary markers were measured for the assessment of renal function, tubular and reperfusion-injury. Renal sections were used for histological grading of renal injury and for immunohistochemical localization of P-selectin, inducible nitric oxide synthase (iNOS) and nitrotyrosine (indicative of peroxynitrite formation). Kidney myeloperoxidase (MPO) activity and malondialdehyde (MDA) levels were measured for assessment of polymorphonuclear (PMN) cell infiltration and lipid peroxidation, respectively. Nitric oxide (NO) production was determined by measurement of plasma nitrite/nitrate levels.. LTA pretreatment significantly reduced renal dysfunction, tubular and reperfusion-injury caused by I/R of the kidney as well as histological evidence of renal injury. LTA also reduced the expression of P-selectin and kidney MPO activity associated with renal I/R. MDA levels were significantly reduced by LTA pretreatment suggesting a reduction in the lipid peroxidation and formation of reactive oxygen species (ROS). LTA pretreatment also markedly reduced both the expression of iNOS and the formation of nitrotyrosine associated with renal I/R. Although LTA significantly reduced plasma nitrite/nitrate levels associated with I/R, nitrite/nitrate levels remained at levels significantly higher than that measured from the plasma obtained from Sham-operated animals.. These data suggest, to our knowledge for the first time, that LTA pretreatment for 24 hours significantly reduces renal I/R injury. We propose that the mechanism of the protective effect involves reduction of the production of NO, ROS and peroxynitrite subsequent to reduced P-selectin and iNOS expression and PMN recruitment. However, although LTA pretreatment resulted in a reduction of iNOS expression and NO production, we hypothesize that the remaining significant levels of NO contribute to the beneficial actions provided by LTA.

Topics: Animals; Antioxidants; Cyclic N-Oxides; Kidney Diseases; Kidney Tubules; Lipopolysaccharides; Male; Malondialdehyde; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; P-Selectin; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Spin Labels; Staphylococcus aureus; Teichoic Acids; Tyrosine

Inflammatory processes have been implicated in the mechanisms of reperfusion injury. The migration of leukocytes into ischemic tissue on reperfusion, which involves binding to the intercellular adhesion molecule (ICAM) of the endothelial cell, is thought to exacerbate tissue injury. The aim of the present study was to assess the effects of an anti-ICAM-1 antibody on reperfusion-induced injury after late reperfusion in a rat middle cerebral artery occlusion (MCAO) suture model.. The animals were divided into four groups: 1) Group 1 (n = 7), 6 hours of permanent MCAO; 2) Group 2 (n = 7), 3 hours of MCAO followed by 3 hours of reperfusion; 3) Group 3 (n = 6), 6 hours of permanent MCAO and treatment with anti-ICAM-1 antibody (designated 1A29, 1 mg/kg) at 2 hours after onset of MCAO; and 4) Group 4 (n = 6), 3 hours of MCAO followed by 3 hours of reperfusion and 1A29 treatment. During the experiment, regional cerebral blood flow was measured by a laser Doppler flowmetric scanning technique. At the 6-hour time point, all rats were killed, and the results of leukocyte infiltration by myeloperoxidase activity and histological analysis using 2,3,5-triphenyltetrazolium chloride staining were examined.. Regional cerebral blood flow values before and after MCAO were not significantly different among the four groups. Regional cerebral blood flow values after reperfusion were not significantly different in the two reperfused groups. The percentage brain injury volumes in both the total and cortical areas and the myeloperoxidase activity in the latter were significantly larger in Group 2 (the reperfused group) than in the other groups (P < 0.05) but were decreased by anti-ICAM-1 antibody treatment (Group 2 versus Group 4, P < 0.05). However, there were no differences between Groups 1 and 3 without reperfusion. Myeloperoxidase activities correlated positively with infarct volumes (P < 0.01).. The findings of this study demonstrate that the anti-ICAM antibody treatment is effective at inhibiting early inflammatory processes and reperfusion-induced injury caused by late arterial recanalization, which would contribute to widening the therapeutic window of thrombolytic therapy.

Topics: Animals; Antibodies; Arterial Occlusive Diseases; Brain; Cerebrovascular Circulation; Intercellular Adhesion Molecule-1; Male; Middle Cerebral Artery; Peroxidase; Rats; Rats, Wistar; Regional Blood Flow; Reperfusion Injury

The objective of this study was to investigate the effects of trimetazidine (TMZ) on tissue damage in kidney after hindlimb ischemia-reperfusion (I/R), by assessing blood biochemical assay and histopathological analysis. Adult male Wistar rats were divided into two groups. TMZ 10 mg kg(-1)day(-1) was administrated twice a day for 10 days to the treatment group (group T, n=10). Sham group was given only 5% gum arabic (group S, n=10). On 11th day of treatment, 8h I/R period was performed on right hindlimb of the rats. At the end of reperfusion period, a 5 ml blood withdrawn from ascending aorta for biochemical assays and their right kidneys were harvested for histopathological examination. Superoxide dismutase, Na(+)-K(+) ATPase, and reduced glutathione levels were significantly increased in group T (P<0.001). On the other hand, myeloperoxidase and malondialdehyde levels were significantly less in group T than group S (P<0.001). Kidneys from the sham-operated group displayed intense leukocytic infiltration in histopathological examination. These overall results strongly suggested that TMZ contributes renal protection from hindlimb I/R injury by decreasing systemic oxidative stress.

Topics: Animals; Glutathione; Hindlimb; Kidney Diseases; Male; Malondialdehyde; Oxidation-Reduction; Peroxidase; Rats; Rats, Wistar; Regional Blood Flow; Reperfusion Injury; Sodium-Potassium-Exchanging ATPase; Superoxide Dismutase; Trimetazidine; Vasodilator Agents

We investigated the effects of OJ-R9545, a novel Sialyl Lewis x analogue, on lung ischemia-reperfusion (IR) injury using an in vivo rabbit model.. The left hilum of the lung was clamped for 110 minutes; the lung was then reperfused for 90 minutes. Either OJ-R9545 (10 mg/kg) or vehicle solution was administered from 10 minutes before reperfusion to 60 minutes after reperfusion in the OJ-R (+) and OJ-R (-) group (n = 6 in each group), respectively. The sham group (n = 3) underwent an identical procedure without ischemia.. Arterial oxygen tensions in the OJ-R (+) group were superior to those in the OJ-R (-) group from 30 to 90 minutes after reperfusion (p < 0.05 and p < 0.01). Lung wet/dry weight ratio and myeloperoxidase activity after reperfusion in the OJ-R (+) group were both significantly lower than the corresponding figures in the OJ-R (-) group (p < 0.05). The intrapulmonary leukocytes were significantly reduced in the OJ-R (+) group compared with those in the OJ-R (-) group (p < 0.01).. OJ-R9545 attenuates lung IR injury by preventing leukocyte infiltration into the lung.

Topics: Animals; Chemotaxis, Leukocyte; Male; Oligosaccharides; Peroxidase; Rabbits; Random Allocation; Reperfusion Injury; Sialyl Lewis X Antigen

Interleukin-10 (IL-10) has potent anti-inflammatory properties but its direct effects on neutrophil trafficking in lung transplant ischemia-reperfusion (I/R) injury are unknown. This study was performed to determine if recipient intramuscular IL-10 gene transfer reduces neutrophil infiltration in lung isografts and ameliorates I/R injury. Twenty-four hours before transplantation, recipient rodents received intramuscular injection with 1 x 10(10) plaque-forming units (pfu) adenovirus encoding human IL-10 (hIL-10), 1 x 10(10) pfu adenovirus control encoding p-galactosidase, or saline. Gene expression in muscle and plasma was confirmed. Lung grafts were harvested, stored at 4 degrees C for 18h, and assessed 24 h after transplantation. Peak muscle and plasma expression of hIL-10 was achieved 24h after gene transfer and returned to baseline by 7 days (p < 0.05 vs. controls). Gene transfer of hIL-10 reduced neutrophil sequestration and emigration in lung grafts as measured by morphometry and myeloperoxidase activity (p < 0.03 vs. controls). Furthermore, hIL-10 improved graft oxygenation and reduced lung edema (p <0.01 vs. controls). Intramuscular gene transfer of hIL-10 releases hIL-10 protein into plasma and reduces neutrophil sequestration and emigration in lung isografts. This is associated with a reduction in I/R injury with improved isograft oxygenation and reduced tissue edema. Intramuscular gene transfer may be a useful strategy to reduce clinical l/R injury.

Topics: Animals; Cell Movement; Gene Transfer Techniques; Immunohistochemistry; Interleukin-10; Lung; Male; Muscles; Neutrophils; Peroxidase; Rats; Rats, Inbred F344; Reperfusion Injury

High pulmonary artery flow rates can result in severe reperfusion injury after lung transplantation. Our hypothesis was that selective activation of the adenosine A(2A) receptor with a highly specific analog (ATL-146e) would inhibit leukocyte activation and decrease reperfusion injury after high-flow reperfusion.. Using our isolated, ventilated, blood-perfused rabbit lung model, all groups (n = 8 per group) underwent lung harvest, 4 hours of cold storage, and blood reperfusion for 30 minutes. Measurements of pulmonary artery pressure (in millimeters of mercury), arterial oxygenation (in millimeters of mercury), myeloperoxidase, peak inspiratory pressure, and wet/dry weight ratio were obtained. Groups 1 (high flow) and 2 (high flow ATL-146e) underwent reperfusion at 120 mL/min for 30 minutes. Groups 3 (controlled high flow) and 4 (controlled high flow ATL-146e) underwent controlled reperfusion with an initial reperfusion of 60 mL/min for the first 5 minutes, followed by a rate of 120 mL/min for 25 minutes. During reperfusion, groups 2 and 4 received ATL-146e at 4 microg. kg(-1). min(-1).. ATL-146e significantly improved lung physiologic measurements under both high-flow (group 1 vs group 2) and controlled high-flow (group 3 vs group 4) conditions after 30 minutes.. The adenosine A(2A) receptor analogue ATL-146e significantly decreases the severity of reperfusion injury in the setting of both high-flow and controlled high-flow reperfusion.

Topics: Animals; Blood Pressure; Cyclohexanecarboxylic Acids; Disease Models, Animal; Enzyme Activation; Female; Lung; Male; Organ Size; Peroxidase; Pulmonary Artery; Pulmonary Wedge Pressure; Purines; Rabbits; Receptor, Adenosine A2A; Receptors, Purinergic P1; Reperfusion; Reperfusion Injury; Time Factors

Ischemia/reperfusion (I/R) injury induces an inflammatory response and production of reactive oxygen species (ROS), which affects the organs remote to the sites of I/R. The aim was to assess the hepatic changes after renal I/R injury.. Twenty mice were subjected to either sham operation or varying degrees of renal I/R injury. Hepatic TNF-alpha levels, myeloperoxidase (MPO), superoxide dismutase (SOD), and catalase (CAT) activities and reduced glutathione (GSH) levels, thiobarbituric acid-reactive substances (TBARS), and protein carbonyl levels were evaluated to show hepatic response to renal I/R injury.. Hepatic tumor necrosis factor-alpha levels were found to be increased significantly after 30 min ischemia-1 h reperfusion and remained elevated through 60 min ischemia-1 h reperfusion. Supporting the neutrophil recruitment, about 10-fold increase in MPO activity was detected after 30 min ischemia-1 h reperfusion. Antioxidant enzymes were detected to be decreased after 30 min ischemia-1 h reperfusion and reached to the minimum levels after 60 min ischemia-1 h reperfusion. Decreased levels of GSH and increased levels of TBARS and protein carbonyls after 60 min ischemia-1 h reperfusion supported the ROS-mediated biomolecular alterations.. A minumum of 30 min ischemia-1 h reperfusion is enough to elicit remote effects of renal I/R injury. Care should be taken to protect other organs remote from I/R sites especially during renal surgery.

Topics: Animals; Catalase; Ischemia; Kidney; Lipid Peroxidation; Liver; Male; Mice; Oxidation-Reduction; Peroxidase; Reactive Oxygen Species; Reperfusion Injury; Superoxide Dismutase; Tumor Necrosis Factor-alpha

Prior ischemia leads to resistance against subsequent ischemic insults. The mechanisms that underlie this adaptive response remain unidentified. Thus, we studied whether the reduced susceptibility of mice previously subjected to the ischemia to ischemia/ reperfusion injury is related with altered inflammatory responses. Thirty minutes of bilateral kidney ischemia results in significantly increased plasma creatinine and blood urea nitrogen levels in BALB/c male mice. There is severe disruption of actin cytoskeleton of proximal tubular cells in the outer stripe of the outer medulla 24 hours post-ischemia. When mice are subjected to 30 minutes of bilateral ischemia 8 days later, there is no increase in plasma creatinine and blood urea nitrogen levels and the post-ischemic disruption of actin cytoskeleton of proximal tubular cells is much less. Inflammatory responses have highly implicated with ischemia/reperfusion injury. Ischemia results in the increased tissue myeloperoxidase (MPO) activity that is a marker of leukocyte infiltration. There is, however, no the post-ischemic increase of MPO activity in kidneys previously subjected to ischemia. Post-ischemic expression of tissue intercellular adhesion molecule-1 (ICAM-1) is greater in the kidney previously sham-operated than in the kidneys previously subjected to ischemia. In conclusion, prior ischemia protects kidney function and morphology against subsequent ischemia 8 days later. The resistance is associated with the reduced post-ischemic leukocyte infiltration due to the reduced post-ischemic ICAM-1 expression.

Topics: Adaptation, Physiological; Animals; Blood Urea Nitrogen; Creatinine; Gene Expression Regulation; Inflammation; Intercellular Adhesion Molecule-1; Ischemia; Kidney; Kidney Tubules, Proximal; Male; Mice; Mice, Inbred BALB C; Peroxidase; Renal Circulation; Reperfusion Injury

Gut barrier failure is an important source of morbidity in critically ill patients, and patients undergoing aortic cross-clamp. Inosine, an endogenous purine nucleoside without known side effects, formed from the breakdown of adenosine by adenosine deaminase, has been shown to modify the effects of hypoxia on various tissues, including the heart and the brain.. This study examined the effect of inosine on ischemia-reperfusion-induced gut barrier dysfunction and on the associated lung injury. Twenty-four male Sprague-Dawley rats were divided into three groups. Eight were subjected to 60 min of superior mesenteric artery occlusion followed by 4 h of reperfusion. Eight had 100 mg/kg inosine prior to ischemia-reperfusion and 8 had sham laparotomy with encircling but not occlusion of the superior mesenteric artery.. Rats treated with inosine had significantly less gut barrier dysfunction. Rats subjected to SMAO sustained a substantial lung injury and this was attenuated by inosine treatment. Serum cytokine levels were also significantly lower.. We conclude that inosine has a beneficial effect in modulating both gut barrier dysfunction and distant organ injury in response to gut ischemia-reperfusion.

Topics: Animals; Dextrans; Disease Models, Animal; Fluorescein-5-isothiocyanate; Heat-Shock Proteins; HSP72 Heat-Shock Proteins; Inosine; Interleukin-6; Intestinal Absorption; Intestinal Mucosa; Intestines; Lung; Lung Diseases; Male; Mesenteric Artery, Superior; Microcirculation; Peroxidase; Pulmonary Circulation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

We have previously shown that prior exposure of rat hind limbs to ischaemia for five minutes and reperfusion for five minutes reduced the structural damage to skeletal muscle which followed a subsequent period of ischaemia for four hours and reperfusion for one hour. We have now examined the potential mechanisms by which this ischaemic preconditioning protocol may be effective in reducing damage to skeletal muscle induced by prolonged ischaemia and reperfusion. Prior exposure of the hindlimb to ischaemia for five minutes and reperfusion for five minutes did not prevent the fall in the ATP content of tibialis anterior which occurred after a subsequent period of ischaemia for four hours and reperfusion for one hour. Similarly, no effect of the preconditioning protocol was seen on the elevated muscle myeloperoxidase, indicative of an elevated neutrophil content, or abnormal muscle cation content. Reperfused ischaemic muscle was also found to have an increased content of heat-shock protein (HSP) 72, but the preconditioning protocol did not further increase the content of this or other HSPs indicating that it was not acting by increasing the expression of these cytoprotective proteins. The protective effects of preconditioning appeared to be mimicked by the infusion of adenosine to animals immediately before exposure to the four-hour period, indicating a potential mechanism by which skeletal muscle may be preconditioned to maintain structural viability.

Topics: Adenosine Triphosphate; Animals; Heat-Shock Proteins; Hindlimb; HSP72 Heat-Shock Proteins; Ischemic Preconditioning; Male; Microscopy, Electron; Muscle, Skeletal; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Neutrophil activation and tumor necrosis factor-alpha (TNF-alpha) induction play a critical role in ischemia-reperfusion-induced intestinal inflammation. Peroxisome proliferator-activated receptor-gamma (PPAR-gamma), a member of the nuclear hormone receptor superfamily, has recently been implicated as a regulator of inflammatory responses. The aim of the present study was to determine whether pioglitazone, a specific PPAR-gamma ligand, can ameliorate reperfusion-induced intestinal injury in rats, and whether the agent can inhibit the increase in neutrophil accumulation associated with TNF-alpha expression. Intestinal damage was induced in male Sprague-Dawley rats by clamping the superior mesenteric artery for 30 min followed by reperfusion. Reperfusion after 30 min ischemia resulted in an increase in luminal protein concentrations with levels reaching a maximum after 60 min of reperfusion. In contrast, pretreatment with pioglitazone 2 h before ischemia inhibited the increase in luminal protein concentrations after 60 min reperfusion in a dose-dependent manner (1-30 mg/kg). The increase in tissue-associated myeloperoxidase activity, an index of neutrophil infiltration, after reperfusion was significantly inhibited by pretreatment with pioglitazone. Pioglitazone also inhibited increases in intestinal TNF-alpha protein and mRNA expression determined by ELISA and RT-PCR, respectively. In conclusion, activation of PPAR-gamma may represent a novel approach to the treatment of intestinal inflammation induced by ischemia-reperfusion.

Topics: Animals; Dose-Response Relationship, Drug; Enzyme-Linked Immunosorbent Assay; Hypoglycemic Agents; Intestinal Mucosa; Ligands; Male; Neutrophils; Peroxidase; Pioglitazone; Rats; Rats, Sprague-Dawley; Receptors, Cytoplasmic and Nuclear; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Thiazoles; Thiazolidinediones; Time Factors; Transcription Factors; Tumor Necrosis Factor-alpha

Peroxisome proliferator-activated receptor-gamma (PPAR-gamma), a member of the nuclear hormone receptor superfamily, has recently been implicated as a regulator of cellular proliferation and inflammatory responses. The aim of the present study was to investigate the effects of pioglitazone on ischemia-reperfusion (I/R)-induced gastric mucosal injury in rats. Gastric ischemia was induced for 30 min by applying a small vascular clamp to the celiac artery and reperfusion was produced by removal of the clamp in male Sprague-Dawley rats treated with and without pioglitazone. Pioglitazone was given to the rats intraperitoneally 2 h before the vascular clamping. The area of gastric mucosal erosion (erosion index) significantly increased from mean basal levels after 60 min of reperfusion. This erosion index was significantly inhibited by pretreatment with pioglitazone in a dose-dependent manner. The concentration of thiobarbituric acid reactive substances (TBARS) and myeloperoxidase (MPO) activity in the gastric mucosa were both significantly increased after I/R, and pretreatment with pioglitazone significantly reduced these increases. The contents of both mucosal TNF-alpha and CINC-2beta in the I/R group were significantly increased compared with the levels in the sham-operated group. These increases in TNF-alpha and CINC-2beta were significantly inhibited by pretreatment with pioglitazone at a dose of 10 mg/kg. The results of the present study indicate that pioglitazone inhibited lipid peroxidation and reduced development of the gastric mucosal inflammation induced by I/R in rats. This investigation suggests that pioglitazone has potential as a new therapeutic agent for reperfusion injury.

Topics: Animals; Chemokines; Chemokines, CXC; Chemotactic Factors; Dose-Response Relationship, Drug; Gastric Mucosa; Hypoglycemic Agents; Intercellular Signaling Peptides and Proteins; Ligands; Lipid Peroxidation; Male; Peroxidase; Pioglitazone; Rats; Rats, Sprague-Dawley; Receptors, Cytoplasmic and Nuclear; Reperfusion Injury; Thiazoles; Thiazolidinediones; Thiobarbituric Acid Reactive Substances; Time Factors; Transcription Factors; Tumor Necrosis Factor-alpha

While tumor necrosis factor (TNF)-alpha is an important mediator of renal ischemia-reperfusion (I/R) injury, its role in contralateral renal injury after isolated renal ischemia remains unknown. We therefore investigated the effect of isolated left renal ischemia on the nonischemic contralateral kidney. To study this, male Sprague-Dawley rats were anesthetized and exposed to varying degrees of left renal I/R injury. Both kidneys were subsequently harvested, serum samples were obtained, and TNF-alpha protein expression (ELISA), TNF-alpha mRNA content (RT-PCR), TNF-alpha immunolocalization, and neutrophil infiltration (myeloperoxidase assay) were determined. The effect of TNF-alpha on neutrophil infiltration was assessed by neutralizing TNF-alpha with TNF binding protein (TNF-BP) before left renal I/R injury. TNF-alpha protein expression, TNF-alpha mRNA induction, and neutrophil infiltration increased significantly in both kidneys after unilateral renal I/R injury. Furthermore, the administration of TNF-BP before unilateral renal I/R substantially reduced the degree of neutrophil infiltration bilaterally. These results constitute the initial demonstration that unilateral renal I/R induces bilateral TNF-alpha production and neutrophil infiltration through a TNF-alpha-dependent mechanism.

Topics: Animals; Blood Pressure; Gene Expression Regulation; Kidney; Kidney Diseases; Male; Neutrophils; Oxygen; Peroxidase; Rats; Rats, Sprague-Dawley; Receptors, Tumor Necrosis Factor; Receptors, Tumor Necrosis Factor, Type I; Reperfusion Injury; RNA, Messenger; Tumor Necrosis Factor Decoy Receptors; Tumor Necrosis Factor-alpha

Peroxynitrite is responsible for nitration in vivo, whereas myeloperoxidase can also catalyze protein nitration in the presence of high NO2(-) levels. Recent reports of myeloperoxidase-mediated enzyme inactivation or lipid peroxidation have suggested a role of myeloperoxidase in various pathological conditions. To clarify the role of myeloperoxidase in ischemic brain injury, the authors measured nitrotyrosine formation and infarct volume in myeloperoxidase-deficient or wild-type mice subjected to 2-hour focal cerebral ischemia-reperfusion. Twenty-four hours after reperfusion, infarct volume was significantly larger in myeloperoxidase-deficient mice than in wild-type mice (81 +/- 20 mm(3) vs. 52 +/- 13 mm(3), P < 0.01), and nitrotyrosine levels in the infarct region were higher in myeloperoxidase-deficient mice than in wild-type mice (13.4 +/- 6.1 microg/mg vs. 9.8 +/- 4.4 microg/mg, P = 0.13). Fourteen hours after reperfusion, the nitrotyrosine level was significantly higher in myeloperoxidase-deficient mice than in wild-type mice (3.3 +/- 2.9 microg/mg vs. 1.4 +/- 0.4 microg/mg, P < 0.05). The authors conclude that the absence of myeloperoxidase increases ischemic neuronal damage in vivo, and that the myeloperoxidase-mediated pathway is not responsible for the nitration reaction in cerebral ischemia-reperfusion.

Topics: Animals; Brain; Brain Infarction; Female; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Peroxidase; Peroxynitrous Acid; Reperfusion Injury; Time Factors; Tyrosine

Melatonin, a pineal hormone, is a free radical scavenger and an antioxidant. The purpose of this study was to assess the protective effect of melatonin on posttransplant lung ischemia-reperfusion injury.. Rat single-lung transplantation was performed in two (n = 10) experimental groups after 18 hours of cold (4 degrees C) ischemia. Group I animals consisted of the ischemic control group. In group II, donor and recipient animals were treated with intraperitoneal injection of 10 mg/kg melatonin 10 minutes before harvest and reperfusion, respectively. After 2 hours of reperfusion, oxygenation, plasma, and bronchoalveolar lavage nitrite levels were measured. Lung tissue was assessed for thiobarbituric acid reactive substances and myeloperoxidase activity. Peak airway pressure was recorded throughout the reperfusion period.. The melatonin-treated group showed significantly better oxygenation (321.8+/-33.8 mm Hg versus 86.1+/-17.4 mm Hg; p < 0.001), reduced lipid peroxidation (0.65+/-0.3 nmol/g versus 1.63+/-0.8 nmol/g; p = 0.032), and reduced myeloperoxidase activity (0.56+/-0.1 deltaOD x mg(-1) x min(-1) versus 1.01+/-0.2 deltaOD x mg(-1) x min(-1); p = 0.032). Bronchoalveolar lavage nitrite levels in the transplanted lungs were significantly lower in group II than in group I (0.34+/-0.06 micromol/L versus 1.65+/-0.6 micromol/L; p = 0.016). In group II significant reduction in peak airway pressure was noted compared with group I (p = 0.002).. In this model, exogenously administered melatonin effectively protected lungs from reperfusion injury after prolonged ischemia.

Topics: Animals; Antioxidants; Free Radical Scavengers; Lipid Peroxidation; Lung Transplantation; Melatonin; Models, Animal; Peroxidase; Random Allocation; Rats; Rats, Inbred F344; Reperfusion Injury; Thiobarbituric Acid Reactive Substances

Oxidative stress after ischemia-reperfusion of cardiac allografts leads to activation of cardiomyocytes and production of cytokines. Bcl-2, an inhibitor of the apoptotic pathway, also has strong antioxidant properties. Ischemia-reperfusion injury after transplantation leads to decreased bcl-2 and increased tumor necrosis factor (TNF)-alpha levels. Transforming growth factor (TGF)-beta1 is known to attenuate ischemia-reperfusion injury and inhibits apoptosis of myofibroblasts. We hypothesize that TGF-beta1, prevents bcl-2 cleavage and increased TNF-alpha production.. Rat PVG donor hearts were heterotopically transplanted into ACI recipients. Donor hearts were procured and assigned to groups: (1) intracoronary TGF-beta1 (200 ng/ml) perfusion and pressure at 78 psi for 45 minutes (n = 4); (2) intracoronary TGF-beta1 perfusion and incubation for 45 minutes without pressure (n = 4), (3) saline perfusion and incubation for 45 minutes without pressure (n = 4). Hearts were procured 4 hours after transplantation and analyzed by reverse transcriptase-polymerase chain reaction for bcl-2 mRNA expression, ELISA for TNF-alpha, and for myeloperoxidase activity (MPO).. Bcl-2 decreased in untreated animals (bcl-2:G3PDH ratio = 0.85 +/- 0.73 vs 1.16 +/- 0.11, not significant [NS]), whereas TNF-alpha increased to 669.99 +/- 127.09 vs 276.84 +/- 73.65 pg/mg total protein in controls (p < 0.003). In TGF-beta(1) pressure-treated hearts, bcl-2 was up-regulated (2.49 +/- 0.6 vs 1.16 +/- 0.11, controls, p < 0.005), whereas TNF-alpha was unchanged (396.1 +/- 100.38 vs 276.84 +/- 73.65 pg/mg, NS). Hearts treated with TGF-beta1 and pressure showed significant up-regulation of bcl-2 compared with hearts treated with TGF-beta1 without pressure (2.49 +/- 0.6 vs 1.17 +/- 0.6, p < 0.02). MPO showed no differences.. Bcl-2 is down-regulated and TNF-alpha up-regulated in this model of ischemia-reperfusion injury. Furthermore, TGF-beta1 is linked to this process and ameliorates reperfusion injury by up-regulating bcl-2 and inhibiting TNF-alpha. Therapeutic overexpression of myocardial TGF-beta1 may be clinically useful to control ischemia-reperfusion injury associated with cardiac transplantation.

Topics: Animals; California; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Genes, bcl-2; Heart Transplantation; Hyperbaric Oxygenation; Male; NF-kappa B; Oxidative Stress; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Transfection; Transforming Growth Factor beta; Transforming Growth Factor beta1; Transplantation, Homologous; Treatment Outcome; Tumor Necrosis Factor-alpha; Up-Regulation

The use of lung grafts from non-heart-beat donors (NHBDs) is one way of solving the critical donor organ shortage. Inhaled nitric oxide (NO) and gabexate mesilate (FOY), a protease inhibitor, can attenuate some types of neutrophil-mediated tissue injury. Using an isolated lung ventilation and perfusion model, we studied the effects of these agents on reperfusion injury following lung transplantation from NHBDs.. Five groups of minipigs were studied. In group 1(n = 6), the lungs were flushed and harvested after cardiac arrest, and were reperfused for 2 hours after 2 hours of cold ischemia. In group 2 (n = 6), the lungs were harvested after 2 hours of in situ warm ischemia, followed by 2 hours of cold ischemia and 2 hours of reperfusion. In groups 3 (n = 7), 4 (n = 7), and 5 (n = 6), the procedure was the same as in group 2, except in group 3, NO was inhaled before and after ischemia, in group 4, FOY was given intravenously, and in group 5, a combination of inhaled NO and intravenous FOY were administered.. Compared with group 1, group 2 had higher mean pulmonary arterial pressure, vascular resistance, and lower arterial blood oxygen tension. Furthermore, these negative effects of warm ischemia were also reflected in the contents of bronchoalveolar lavage fluid, tissue myeloperoxidase (MPO) activity, histology, and permeability change. Either FOY or NO administration (groups 3 or 4) ameliorated the associated injury. A combination of FOY and NO use (group5) decreased the parameters of lung reperfusion injury measurement to a larger degree than either agent individually.. The inhaled NO and FOY can protect NHBD lung grafts at an early reperfusion period. Their use in combination has an additive protective effect that might be applied to the protection of NHBD grafts from preservation and reperfusion injury.

Topics: Administration, Inhalation; Animals; Blood Gas Analysis; Bronchoalveolar Lavage Fluid; Capillary Permeability; Drug Therapy, Combination; Gabexate; Heart Transplantation; Lung; Lung Injury; Lung Transplantation; Neutrophil Infiltration; Neutrophils; Nitric Oxide; Peroxidase; Pulmonary Wedge Pressure; Reperfusion Injury; Swine, Miniature; Time Factors; Tissue Donors; Vascular Resistance

The aim of the present study was to assess the role of endothelin (ET) in ischemia-reperfusion (I/R)-induced mucosal injury. Mucosal permeability ((51)Cr-EDTA clearance) and tissue myeloperoxidase (MPO) activity were significantly increased after 30 min of ischemia followed by 30 min of reperfusion. The I/R-induced increases in mucosal permeability and polymorphonuclear leukocyte (PMN) infiltration were significantly attenuated by pretreatments with ET(A) (BQ-485) and/or ET(B) (BQ-788) receptor antagonists. Monoclonal antibody (MAb) directed against intercellular adhesion molecule-1 (ICAM-1; MAb 1A29) and superoxide dismutase (SOD) pretreatments significantly attenuated the increased mucosal permeability and PMN infiltration in a similar manner as with ET receptor antagonists. Superior mesenteric artery blood flow was significantly reduced during the reperfusion period. Both ET receptor antagonists caused a significant rise in blood flow compared with an untreated I/R group. In conclusion, our data suggest that ET(A) and/or ET(B) receptors, ICAM-1, and superoxide play an important role in I/R-induced mucosal dysfunction and PMN infiltration. Furthermore, ET is involved in the pathogenesis of post-reperfusion-induced damage and beneficial effects of ET receptor antagonism are related to an improvement of disturbed blood flow during the reperfusion period.

Topics: Animals; Antibodies, Monoclonal; Azepines; Blood Flow Velocity; Blood Pressure; Cell Membrane Permeability; Endothelin Receptor Antagonists; Endothelin-1; Endothelins; Female; Intercellular Adhesion Molecule-1; Intestinal Mucosa; Male; Mesenteric Artery, Superior; Neutrophils; Oligopeptides; Peroxidase; Piperidines; Rats; Rats, Wistar; Receptor, Endothelin A; Receptor, Endothelin B; Receptors, Endothelin; Reperfusion Injury; Superoxide Dismutase

The aim of the present study was to investigate the effects of GPI 6150, a new poly(ADP-ribose) polymerase (PARP) inhibitor, in the pathogenesis of splanchnic artery occlusion (SAO) shock. SAO shock was induced in rats by clamping both the superior mesenteric artery and the celiac trunk for 45 min, followed by reperfusion. At 60 min after reperfusion, SAO-shocked rats developed a significant fall in mean arterial blood pressure, significant increase of tissue myeloperoxidase activity (111 +/- 4.3 U/100 mg wet tissue vs. 28 +/- 3.2 U/100 mg wet tissue of sham-operated rats), and marked histological injury to the distal ileum and a significant mortality (0% survival at 2 h after reperfusion). Immuno-histochemical examination demonstrated a marked increase in the immunoreactivity to PARP, P-selectin, and intercellular adhesion molecule (ICAM-1) in the necrotic ileum. GPI 6150 treatment significantly improved mean arterial blood pressure, prevented the infiltration of neutrophils (72 +/- 3.6 U/100 mg wet tissue) into the reperfused intestine, improved the histological status of the reperfused tissues, markedly reduced the intensity of P-selectin and ICAM-1 in tissue section from SAO-shocked rats, and improved survival. In conclusion, our study demonstrates that GPI 6150 exerts multiple protective effects in splanchnic artery occlusion/reperfusion shock.

Topics: Animals; Benzopyrans; Blood Pressure; Enzyme Inhibitors; Intercellular Adhesion Molecule-1; Intestinal Mucosa; Intestines; Isoquinolines; Male; Mesenteric Artery, Superior; Mesenteric Vascular Occlusion; Neutrophils; P-Selectin; Peroxidase; Poly(ADP-ribose) Polymerase Inhibitors; Rats; Rats, Sprague-Dawley; Reperfusion; Reperfusion Injury; Splanchnic Circulation; Survival Rate

The overall objective of this study was to define the contribution of T-lymphocytes to the microvascular and inflammatory responses of the intestine to ischemia/reperfusion (I/R).. The superior mesenteric artery of wild-type (WT) and SCID mice was occluded for 45 minutes, followed by 30 minutes or 6 hours of reperfusion. Intravital fluorescence microscopy was used to monitor the extravasation of FITC-labeled albumin or the adhesion of carboxy-fluorescein diacetate succinimidyl ester (CFSE)-labeled T-lymphocytes in mucosal venules of the postischemic intestine. Tissue myeloperoxidase (MPO) was used to monitor neutrophil accumulation in the intestine of WT and SCID mice.. Although the number of adherent T-cells was not increased above baseline at 1 hour after reperfusion, significant T-cell adhesion (both CD4(+) and CD8(+)) was noted at 6 hours of reperfusion. The latter response was prevented by pretreatment with a blocking antibody directed against MAdCAM-1, but not ICAM-1 or VCAM-1. A significant increase in MAdCAM-1 expression was noted in both lymphoid (Peyer's patch) and nonlymphoid regions of the postischemic small bowel. The early (30 minutes after reperfusion) albumin extravasation elicited by gut I/R in WT mice was reduced in SCID mice. Reconstitution of SCID mice with T-lymphocytes restored the albumin leakage response to WT levels. The increased intestinal MPO caused by I/R (6 hours of reperfusion) in WT mice was attenuated in SCID mice; with reconstitution of SCID mice with T-cells the MPO response was restored.. These findings indicate that intestinal I/R is associated with the recruitment of CD4+ and CD8+ T-cells, which is mediated by endothelial MAdCAM-1. T-cells seem to modulate the recruitment of neutrophils that occurs hours after reperfusion as well as the increased albumin extravasation that occurs within minutes after reperfusion.

Topics: Animals; Antibodies, Monoclonal; Cell Adhesion; Cell Adhesion Molecules; Endothelium, Vascular; Immunoglobulins; Inflammation; Intercellular Adhesion Molecule-1; Intestines; Mesenteric Artery, Superior; Mice; Mice, Inbred C57BL; Mice, SCID; Microcirculation; Mucoproteins; Neutrophils; Peroxidase; Reperfusion Injury; T-Lymphocytes; Vascular Cell Adhesion Molecule-1

This investigation examined the effectiveness of a serine protease inhibitor (LEX032) when used as a cerebral protective agent after ischemia. Focal cerebral ischemia in the rat was produced by intravascular occlusion of the middle cerebral artery for a period of 30 min. Just prior to thread withdrawal (i.e., reperfusion), rats received an iv bolus administration of either vehicle or LEX032 (50 mg/kg), an optimal dose chosen based on previous studies. Somatosensory evoked potentials (SSEP's) were monitored prior to, during, and for a period of 60 min after removal of occlusion. The animals were allowed to recover for 24 h after the ischemic insult. Cortical activity in the occluded region, as assessed by SSEPs, returned much sooner in the LEX032-treated animals (10 +/- 6 min) than in the untreated animals (40 +/- 25 min). On a scale ranging from 0 to 3, with three indicating the most severely injured, the LEX032 animals had a significantly better neurologic score (1.0 +/- 0.9) than the untreated animals (2.3 +/- 0.5) 24 h after ischemia. The improved neurobehavior was related to a 55% reduction in brain injury as assessed by TTC staining. LEX032-treated animals had significantly (P < 0.01) smaller infarcts (115 +/- 40 mm3) compared to vehicle-treated animals (263 +/- 13 mm3). In a separate group of animals (n = 6/group), leukocyte infiltration, as evaluated by tissue myeloperoxidase activity (MPO U/g tissue wt), was also significantly (P < 0.05) lower in the LEX032-treated animals (1.4 +/- 0.3) compared to vehicle-treated animals (3.6 +/- 0.7). This data demonstrates that LEX032 reduces brain injury and suggests that serine protease inhibitors may reduce ischemia/reperfusion injury by decreasing leukocyte activation and migration.

Topics: Animals; Brain; Brain Ischemia; Cell Adhesion; Cell Movement; Evoked Potentials; Humans; Neutrophils; Peroxidase; Protease Inhibitors; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Reperfusion Injury; Serpins; Temperature; Time Factors

Calcineurin inhibitors reduce experimental reperfusion injury in the liver, brain, heart, kidney, and small bowel. These studies were undertaken to determine whether these agents are similarly protective against lung ischemia-reperfusion injury.. Left lungs of male rats were rendered ischemic for 90 minutes and reperfused for as long as 4 hours. Treated animals received cyclosporine A (INN: ciclosporin; 1 or 5 mg/kg) or tacrolimus (0.2 mg/kg) 6 hours before ischemia, at reperfusion, or 2 hours after reperfusion. Injury was quantitated in terms of tissue polymorphonuclear leukocyte accumulation (myeloperoxidase content), vascular permeability (iodine 125-labeled bovine serum albumin extravasation), and bronchoalveolar lavage leukocyte content. Separate tissue samples were processed for nuclear protein and cytokine messenger RNA.. Treatment with cyclosporine (5 mg/kg) or tacrolimus (0.2 mg/kg) 6 hours before reperfusion reduced lung vascular permeability by 54% and 56% relative to control animals (P <.03). The protective effects of cyclosporine and tacrolimus treatment before reperfusion correlated with 42% and 43% reductions in tissue polymorphonuclear leukocyte (myeloperoxidase) content (P <.008) and marked reductions in bronchoalveolar lavage leukocyte accumulation (P <.01). Administration of cyclosporine or tacrolimus at the time of reperfusion or 2 hours into the reperfusion period offered little or no protection. Animals treated before reperfusion also demonstrated marked reductions in nuclear factor kappaB activation and expression of proinflammatory cytokine messenger RNA.. Cyclosporine and tacrolimus treatment before reperfusion was protective against lung ischemia-reperfusion injury in rats. The mechanism of these protective effects may involve the inhibition of nuclear factor kappaB, a central transcription factor mediating inflammatory injury. The decreased expression of cytokine messenger RNA indicates that both cyclosporine and tacrolimus may exert their protective effects at the pretranscriptional level.

Topics: Animals; Bronchoalveolar Lavage Fluid; Capillary Permeability; Cyclosporine; Cytokines; Disease Models, Animal; Dose-Response Relationship, Drug; Electrophoretic Mobility Shift Assay; Immunosuppressive Agents; Leukocytes; Lung; Male; NF-kappa B; Peroxidase; Preoperative Care; Rats; Rats, Long-Evans; Reperfusion Injury; RNA, Messenger; Tacrolimus; Treatment Outcome

This study was undertaken to determine whether low-dose endobronchial transfer to the donor of the gene for human interleukin 10 would decrease ischemia-reperfusion injury in lung transplantation.. Experiments used male Fischer rats. Donor animals underwent right thoracotomy. A catheter was introduced into the left main bronchus, and vector was instilled. Group I (n = 6) received 2 x 10(7) plaque-forming units of adenovirus encoding human interleukin 10, group II (n = 6) received an adenovirus control encoding beta-galactosidase, and group III (n = 6) received saline solution. After instillation the left main bronchus was clamped for 60 minutes. Lungs were removed 24 hours later and stored in low-potassium dextran glucose solution for 18 hours before left lung transplantation. Graft function was assessed at 24 hours immediately before the animals were killed. Ratio of wet to dry weight and tissue myeloperoxidase activity were measured. Transgenic expression of human interleukin 10 was evaluated by means of enzyme-linked immunosorbent assay and immunohistochemical assay.. Arterial oxygenation was significantly improved in group I relative to groups II and III (257.6 +/- 59.7 mm Hg vs 114.6 +/- 66.9 mm Hg and 118.6 +/- 91.1 mm Hg, P =.008 and P =.007, respectively). Neutrophil sequestration, as measured by myeloperoxidase activity, was also significantly reduced in group I relative to groups II and III (0.141 +/- 0.025 vs 0.304 +/- 0.130 and 0.367 +/- 0.153 Delta optical density units/[min. mg protein], P =.029 and P =.004, respectively). Enzyme-linked immunosorbent assay and immunohistochemical assay demonstrated the expression of human interleukin 10 in transfected lungs only.. Low-dose endobronchial transfer to the donor of the gene for human interleukin 10 ameliorated ischemia-reperfusion injury in rodent lung transplantation by improving graft oxygenation and reducing neutrophil sequestration. Only 2 x 10(7) plaque-forming units of adenoviral vector were required for functional transgenic expression. Endobronchial gene transfer to lung grafts may be a useful delivery route even at low doses.

Topics: Animals; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme-Linked Immunosorbent Assay; Gene Expression; Gene Transfer Techniques; Genetic Vectors; Immunohistochemistry; Interleukin-10; Lung; Lung Transplantation; Male; Peroxidase; Pulmonary Gas Exchange; Rats; Rats, Inbred F344; Reperfusion Injury

Intestinal ischaemia-reperfusion can lead to pulmonary injury characterised by increased macromolecular leakage and leukocyte sequestration. Important mediators of ischaemia-reperfusion-associated injury include polymorphonuclear granulocytes and platelet-activating factor.. To investigate the potential therapeutic inhibition of platelet-activating factor in intestinal ischaemia-reperfusion associated pulmonary injury, by use of a potent platelet-activating factor-receptor antagonist, lexipafant.. Rats were subjected to 30 minutes of intestinal ischaemia followed by 3 or 12 hours reperfusion. Lexipafant or saline was given intraperitoneally after 30 minutes reperfusion.. Increased leakage of radiolabelled human serum albumin was found in the lungs after intestinal ischaemia followed by 3 or 12 hours reperfusion. Administration of lexipafant did not significantly prevent the increased leakage. Pulmonary myeloperoxidase content increased after intestinal ischaemia-reperfusion, indicating polymorphonuclear granulocyte sequestration through the pulmonary endothelium. The increase in interleukin-1beta seen after 3 hours reperfusion was partly reversed by lexipafant.. Pulmonary injury occurred following intestinal ischaemia-reperfusion, characterised by increased leakage of radiolabelled albumin over the endothelial barrier; correlating with increased pulmonary myeloperoxidase-content, implying involvement of polymorphonuclear granulocytes in the pathogenesis of remote organ injury after intestinal ischaemia-reperfusion. Lexipafant did not significantly decrease severity of pulmonary damage.

Topics: Animals; Endothelium, Vascular; Imidazoles; Interleukin-1; Leucine; Lung; Male; Peroxidase; Platelet Activating Factor; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Treatment Failure

We determined the change in contractile activity and oxidant damage after ischemia-reperfusion of rat corpus cavernosum and investigated the effects of melatonin (Sigma Chemical Co., St. Louis, Missouri) on these parameters.. The abdominal aorta of male Wistar albino rats was occluded to induce ischemia-reperfusion. Melatonin (10 mg./kg.) or vehicle (1% alcohol in saline per kg.) was administered subcutaneously before ischemia-reperfusion. In the sham operated control group the abdominal aorta was left intact and the rats were treated with melatonin or vehicle. After decapitation corporeal tissues were placed in organ baths or stored for biochemical measurements.. In sham operated rats phenylephrine added cumulatively caused a concentration dependent contraction in corpus cavernosum strips precontracted with KCl and acetylcholine added cumulatively to strips precontracted with phenylephrine caused a dose dependent relaxation response. In the ischemia-reperfusion group contraction and relaxation responses decreased significantly compared within controls. Melatonin treatment in the ischemia-reperfusion group reversed these responses. Myeloperoxidase activity and the lipid peroxidation level of the corporeal tissues in the ischemia-reperfusion group were significantly higher than in the sham operated control group. Melatonin treatment in the ischemia-reperfusion group decreased myeloperoxidase activity and the lipid peroxidation level compared with ischemia-reperfusion alone, whereas melatonin treatment alone had no significant effect on these parameters.. In this study the corporeal tissues of rats exposed to ischemia-reperfusion had lower responses to contractile and relaxant agents than those of sham operated rats. Treatment with melatonin before ischemia-reperfusion almost completely reversed smooth muscle responses and prevented the increased myeloperoxidase activity and lipid peroxidation of corporeal tissues.

Topics: Acetylcholine; Animals; Antioxidants; Free Radical Scavengers; In Vitro Techniques; Lipid Peroxidation; Male; Malondialdehyde; Melatonin; Muscle Contraction; Muscle, Smooth; Penis; Peroxidase; Phenylephrine; Rats; Rats, Wistar; Reperfusion Injury

Capsaicin-sensitive sensory neurons are nociceptive neurons that release calcitonin gene-related peptide (CGRP) on activation by various noxious stimuli. CGRP has been shown to increase the endothelial production of prostacyclin, which reduces ischemia/reperfusion (I/R)-induced liver injury. Therefore, if the sensory neurons can be activated by the pathologic process of hepatic I/R, they might help ameliorate I/R-induced liver injury by promoting the endothelial production of prostacyclin, also known as prostaglandin I(2). In this study, we examined these possibilities using a rat model of I/R-induced liver injury. Male Wistar rats were subjected to 60-minute hepatic ischemia and subsequent reperfusion. Hepatic levels of 6-keto-prostaglandin F(1alpha) (6-keto-PGF(1alpha)), a stable metabolite of prostacyclin, were significantly increased after hepatic I/R, peaking 1 hour after reperfusion. Administration of capsaicin and CGRP significantly enhanced I/R-induced increases in hepatic levels of 6-keto-PGF(1alpha), increased hepatic-tissue blood flow after reperfusion, and inhibited the I/R-induced increase in tissue levels of both tumor necrosis factor-alpha (TNF-alpha) and myeloperoxidase. Capsazepine, a vanilloid receptor antagonist; CGRP(8-37), a CGRP-receptor antagonist; l-nitro-arginine-methyl-ester (L-NAME), a nonselective inhibitor of nitric oxide (NO) synthase (NOS); and indomethacin, a nonselective inhibitor of cyclooxygenase, inhibited the I/R-induced increases in hepatic tissue levels of 6-keto-PGF(1alpha) and decreased hepatic-tissue blood flow after reperfusion. These compounds significantly enhanced the I/R-induced increases in hepatic tissue levels of both TNF-alpha and myeloperoxidase. Although I/R-induced liver injury was significantly reduced by capsaicin and CGRP, it was exacerbated by capsazepine, CGRP(8-37), L-NAME, and indomethacin. Administration of aminoguanidine, a selective inhibitor of the inducible form of NOS, and NS-398, a selective inhibitor of cyclooxygenase-2, demonstrated no effects on the liver injury or the hepatic levels of 6-keto-PGF(1alpha). These findings strongly suggest that the activation of the sensory neurons helps ameliorate I/R-induced liver injury both by increasing hepatic-tissue blood flow and by limiting inflammatory response through the enhancement of endothelial production of prostacyclin. In the sensory neuron-mediated enhancement of endothelial production of prostacyclin, CGRP-induced activation of both e

Topics: 6-Ketoprostaglandin F1 alpha; Animals; Calcitonin Gene-Related Peptide; Capsaicin; Cyclooxygenase 1; Cyclooxygenase Inhibitors; Enzyme Inhibitors; Epoprostenol; Guanidines; Indomethacin; Isoenzymes; Liver; Liver Circulation; Male; Membrane Proteins; Miotics; Neurons, Afferent; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitrobenzenes; Peptide Fragments; Peroxidase; Prostaglandin-Endoperoxide Synthases; Rats; Rats, Wistar; Reperfusion Injury; Specific Pathogen-Free Organisms; Sulfonamides; Transaminases; Tumor Necrosis Factor-alpha

Some investigators have suggested that high pulmonary artery flow rates increase the risk of severe reperfusion injury after lung transplantation. We hypothesized that controlling the initial flow rate and pulmonary artery pressure would decrease the severity of lung dysfunction in the setting of high-flow reperfusion.. Using our isolated, ventilated, blood-perfused rabbit lung model, all groups underwent lung harvest, 4-hour storage (4 degrees C), and blood reperfusion. We measured pulmonary artery pressure, peak inspiratory pressure, arterial oxygenation, and wet-to-dry weight ratio. Group 1 (control, n = 8) underwent reperfusion at 60 ml/min for 30 minutes. Group 2 (high flow, n = 8) underwent reperfusion at 120 ml/min for 30 minutes. Group 3 (controlled flow, n = 8) underwent initial reperfusion at 60 ml/min for 5 minutes, followed by reperfusion at 120 ml/min for 25 minutes.. Group 1 had significantly improved pulmonary artery pressure, peak inspiratory pressure, arterial oxygenation, and wet-to-dry weight ratio measurements compared with groups 2 and 3 after 30 minutes of reperfusion. However, Group 3 had improved pulmonary artery pressure, peak inspiratory pressure, arterial oxygenation, and wet-to-dry weight ratio measurements compared with Group 2.. High-flow reperfusion results in severe reperfusion injury after lung transplantation. Controlled reperfusion using a low initial flow rate decreases the severity of reperfusion injury associated with high-flow rates.

Topics: Animals; Blood Pressure; Disease Models, Animal; Lung Transplantation; Organ Preservation; Perfusion; Peroxidase; Rabbits; Reperfusion Injury

Gastrointestinal ischemia-reperfusion (I/R) injury is often associated with remote tissue injury. Complement activation plays an important role in local and remote tissue injury associated with gastrointestinal I/R. We developed a new murine model of gastrointestinal I/R that has complement-dependent local and remote tissue injury. Twenty, but not thirty, minutes of gastrointestinal ischemia followed by 3 h of reperfusion induced a significant loss of intestinal lactate dehydrogenase that was significantly prevented by a murine anti-murine C5 monoclonal antibody. Anti-C5 also significantly decreased neutrophil infiltration into the gut and lung. Gastrointestinal I/R significantly increased pulmonary intercellular adhesion molecule-1 mRNA and protein expression that was significantly inhibited by anti-C5. Pulmonary macrophage inflammatory protein-2 mRNA was significantly induced by gastrointestinal I/R and inhibited by anti-C5 treatment. These data demonstrate that brief periods of murine gastrointestinal I/R activate complement, leading to tissue injury and neutrophil accumulation. Anti-C5 treatment attenuates tissue injury, neutrophil recruitment, and leukocyte adherence molecule and chemokine expression in the mouse. This model will be well suited to investigate the role of complement-mediated tissue injury and gene expression after gastrointestinal I/R.

Topics: Animals; Coloring Agents; Complement C5; Complement System Proteins; Digestive System; Gastrointestinal Diseases; Immunohistochemistry; Intercellular Adhesion Molecule-1; Intestines; L-Lactate Dehydrogenase; Lung; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Peroxidase; Regional Blood Flow; Reperfusion Injury; Reproducibility of Results; Reverse Transcriptase Polymerase Chain Reaction

Oxygen free radicals are considered to be important components involved in the pathophysiological tissue alterations observed during ischemia-reperfusion (I/R). In this study, we investigated the putative protective effects of melatonin treatment on renal I/R injury. Wistar albino rats were unilaterally nephrectomized and subjected to 45 min of renal pedicle occlusion followed by 1, 3, 6, 24, 48 hr or 1 wk of reperfusion. Melatonin (10 mg/kg, s.c.) or vehicle was administered twice, 15 min prior to ischemia and immediately before the reperfusion period. At the end of the reperfusion periods, rats were decapitated. Kidney samples were taken for histological examination or the determination of renal malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and protein oxidation (PO). Serum creatinine and blood urea nitrogen (BUN) concentrations were measured for the evaluation of renal function. The results revealed that I/R induced nephrotoxicity, as evidenced by increases in BUN and creatinine levels at each time point, was reversed by melatonin treatment. The decrease in GSH and increases in MDA, MPO and PO induced by I/R indicated that renal injury involves free radical formation. As melatonin administration reversed these oxidant responses, improved renal function and microscopic damage, it seems likely that melatonin protects kidney tissue against oxidative damage.

Topics: Animals; Blood Urea Nitrogen; Creatinine; Glutathione; Kidney; Male; Malondialdehyde; Melatonin; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

The present study was designed to investigate the effect of amrinone, a phosphodiesterase III inhibitor, on hepatic ischemia-reperfusion injury in rats.. Amrinone was infused at a rate of 20 or 100 microg/kg/min, and 60-min partial ischemia was induced. The effects of amrinone on hemodynamic status, hepatic tissue cyclic adenosine 5'-monophosphate (cAMP), hepatic tissue blood flow, platelet aggregation and plasma levels of transaminase were examined. The expression of intercellular adhesion molecule-1 (ICAM-1) and myeloperoxidase activity were analyzed and histological examination was performed in the injured liver. The cumulative survival rates for 14 days were also examined.. Hemodynamic status was not affected by amrinone. The levels of cAMP during reperfusion were significantly higher in rats with amrinone. Hepatic tissue blood flow during reperfusion was increased and platelet aggregation was inhibited by amrinone. The expression of ICAM-1 mRNA and protein in the injured liver was suppressed in rats with amrinone. The levels of transaminase, necrotic changes and myeloperoxidase activity were suppressed after reperfusion and higher survival was achieved in the rats treated with amrinone.. Amrinone protected against ischemia-reperfusion injury of the liver in the present model.

Topics: Alanine Transaminase; Amrinone; Animals; Aspartate Aminotransferases; Blotting, Western; Cyclic AMP; Gene Expression; Immunohistochemistry; In Situ Nick-End Labeling; Intercellular Adhesion Molecule-1; Liver; Liver Circulation; Liver Diseases; Male; Peroxidase; Phosphodiesterase Inhibitors; Platelet Aggregation; Rats; Rats, Wistar; Reperfusion Injury; RNA, Messenger; Survival Rate

Multiple organ dysfunction syndrome (MODS) is mediated by complex mechanisms in which interactions between activated leukocytes and endothelial cells play a central role. ICAM-1 (intercellular adhesion molecule-1) mediates firm adhesion and transendothelial migration of activated leukocytes from postcapillary venules into the tissue. The present study evaluated the ICAM-1 expression in various organs after 40 min of intestinal ischemia and 1, 3, 6, 12 h of reperfusion (I/R) in the rat, using a dual monoclonal antibody technique (n = 36). Endothelial barrier permeability, using the vascular leakage of radiolabeled human serum albumin was also assessed (n = 12). Neutrophil sequestration in the lungs was quantitated by myeloperoxidase activity and plasma protease inhibitor levels were measured with electroimmunoassay. Significant regional differences were found in ICAM-1 expression between organs, both constitutively and after I/R-injury. The highest constitutive levels were observed in the liver and lungs, followed by the kidneys. The constitutive ICAM-1 expression in the intestines and in the heart was about 1/20 compared with that found in the liver and lungs. The brain and muscle had levels of about 1/150 of that in the liver and lungs. After intestinal I/R, significant increases (17-45%) were found in the lungs, intestines, brain, heart, and muscle. Albumin leakage index (ALI) in all examined organs and myeloperoxidase activity in the lungs increased after I/R-injury. Serum levels of albumin and most protease inhibitors decreased significantly after I/R challenge. Intestinal I/R results in an increase of systemic ICAM-1 expression with marked organ variability. The upregulation of ICAM-1 could represent a crucial step in the adherence- and migration process of activated leukocytes and potentially in the development of tissue injury.

Topics: Albumins; Animals; Antibodies, Monoclonal; Endothelium, Vascular; Inflammation; Intercellular Adhesion Molecule-1; Intestinal Mucosa; Intestines; Ischemia; Male; Molecular Biology; Neutrophils; Permeability; Peroxidase; Protease Inhibitors; Rats; Rats, Sprague-Dawley; Reperfusion Injury

1. Splanchnic artery occlusion shock (SAO) causes an enhanced formation of reactive oxygen species (ROS), which contribute to the pathophysiology of shock. Here we have investigated the effects of M40401, a new S:,S:-dimethyl substituted biscyclohexylpyridine Mn-based superoxide dismutase mimetic (SODm, k(cat)=1.2x10(+9) M(-1) s(-1) at pH=7.4), in rats subjected to SAO shock. 2. Treatment of rats with M40401 (applied at 0.25, 2.5 or 25 microg kg(-1), 15 min prior to reperfusion), attenuated the mean arterial blood and the migration of polymorphonuclear cells (PMNs) caused by SAO-shock. M40401 also attenuated the ileum injury (histology) as well as the increase in the tissue levels of myeloperoxidase (MPO) and malondialdehyde (MDA) caused by SAO shock in the ileum. 3. Immunohistochemical analysis for nitrotyrosine revealed a positive staining in ileum from SAO-shocked rats. The degree of staining for nitrotyrosine was markedly reduced in tissue sections obtained from SAO-shocked rats which had received M40401. Reperfused ileum tissue sections from SAO-shocked rats showed positive staining for P-selectin and for anti-intercellular adhesion molecule (ICAM-1) in the vascular endothelial cells. M40401 treatment markedly reduced the intensity and degree of P-selectin and ICAM-1 in tissue sections from SAO-shocked rats. M40401 treatment significantly improved survival. 4. Additionally, the very high catalytic activity of this new mimetic (comparable to the native human Cu/Zn SOD enzyme and exceeding the activity of the human Mn SOD enzyme) translates into a very low dose ( approximately microg kg(-1)) required to afford protection in this SAO model of ischemia reperfusion injury. 5. Taken together, our results clearly demonstrate that M40401 treatment exerts a protective effect, and part of this effect may be due to inhibition of the expression of adhesion molecules and peroxynitrite-related pathways with subsequent reduction of neutrophil-mediated cellular injury.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Arterial Occlusive Diseases; Catalysis; Cytokines; Fluorescent Antibody Technique; Ileum; Leukocyte Count; Male; Malondialdehyde; Manganese; Nitrates; Nitrites; Organometallic Compounds; P-Selectin; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Splanchnic Circulation; Superoxide Dismutase; Superoxides; Tyrosine

Peroxisome proliferator-activated receptor gamma (PPAR gamma) is a nuclear receptor whose activation has been linked to several physiologic pathways including those related to the regulation of intestinal inflammation. We sought to determine whether PPAR gamma could function as an endogenous anti-inflammatory pathway in a murine model of intestinal ischemia-reperfusion (I/R) injury.. PPAR gamma-deficient and wild-type mice were examined for their response to I/R procedure. Treatment with a PPAR gamma-specific ligand was also performed.. In a murine model of intestinal I/R injury, we observed more severe injury in PPAR gamma-deficient mice and protection against local and remote tissue injury in mice treated with a PPAR gamma-activating ligand, BRL-49653. Activation of PPAR gamma resulted in down-regulation of intercellular adhesion molecule 1 expression by intestinal endothelium and tissue tumor necrosis factor alpha messenger RNA levels most likely by inhibition of the NF-kappa B pathway.. These data strongly suggest that an endogenous PPAR gamma pathway exists in tissues that may be amenable to therapeutic manipulation in I/R-related injuries.

Topics: Animals; Cells, Cultured; Colitis; Epithelial Cells; Gastric Mucosa; Gene Expression; Hypoglycemic Agents; In Vitro Techniques; Intercellular Adhesion Molecule-1; Interleukin-8; Intestinal Mucosa; L-Lactate Dehydrogenase; Liver; Mice; Mice, Inbred BALB C; Mice, Knockout; NF-kappa B; Peroxidase; Pneumonia; Receptors, Cytoplasmic and Nuclear; Reperfusion Injury; RNA, Messenger; Rosiglitazone; Stomach; Thiazoles; Thiazolidinediones; Transcription Factors; Tumor Necrosis Factor-alpha

Risk factors for cardiovascular disease have been shown to exacerbate the inflammatory response and microvascular dysfunction that is normally associated with ischemia-reperfusion. The objective of this study was to determine whether hypercholesterolemia and/or hypertension alter I/R-induced expression of P-selectin in the intestinal vasculature. Male control and hypertensive (HTN) rats were placed on either a normal diet or high cholesterol diet (HCD) for at least 3 weeks resulting in hypercholesterolemia (HC). Ischemia was induced by occlusion of the superior mesenteric artery for 15 min, followed by either 30 min or 4 h of reperfusion. The dual radiolabeled antibody technique was used to quantify the rapid (30 min) and transcription-dependent (4 h) expression of P-selectin. Tissue myeloperoxidase (MPO) was used to quantify neutrophil infiltration. The constitutive (basal) expression of P-selectin did not differ among the experimental groups. Although I/R significantly increased P-selectin expression in control, HC, and HTN+HC, P-selectin expression did not increase in HTN. The HC group exhibited the largest increments in P-selectin expression and tissue MPO after I/R. The increment in P-selectin expression was not significantly attenuated in HC rats that were rendered thrombocytopenic with anti-platelet serum. Treatment with an anti-P-selectin antibody largely prevented the exaggerated MPO increase noted in HC. These findings indicate that hypercholesterolemia in contrast to hypertension enhances the expression of P-selectin in the postischemic intestinal vasculature.

Topics: Animals; Biomarkers; Blood Pressure; Cholesterol; Hypercholesterolemia; Hypertension; Male; Mesenteric Arteries; Mesentery; P-Selectin; Peroxidase; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Reperfusion Injury; Up-Regulation

Although nitric oxide (NO) is thought to be beneficial in hepatic ischemia-reperfusion (I/R), the mechanisms for this effect are not well established.. To investigate the effects of endogenous NO and exogenous NO supplementation on hepatic I/R injury and their pathogenic mechanisms, serum ALT and hyaluronic acid (endothelial cell damage), and hepatic malondialdehyde and H2O2 (oxidative stress), myeloperoxidase activity (leukocyte accumulation), and endothelin (vasoconstrictor peptide opposite to NO) were determined at different reperfusion periods in untreated rats and rats receiving L-NAME, L-NAME+L-arginine, and spermine NONOate (exogenous NO donor).. After reperfusion every parameter increased in untreated animals. Endogenous NO synthesis inhibition by L-NAME increased hepatocyte and endothelial damage as compared to untreated rats, which was reverted and even improved by the addition of L-arginine. Spermine NONOate also improved this damage. However, different mechanisms account for the beneficial effect of endogenous and exogenous NO. Oxidative stress decreased by both L-NAME and L-NAME+L-arginine, but remained unmodified by spermine NONOate. Myeloperoxidase increased by L-NAME and this effect was reverted by the addition of L-arginine, whereas no change was observed with spermine NONOate. Endothelin levels were not modified by L-NAME and L-NAME+L-arginine, but decreased with spermine NONOate.. These results suggest that, although both endogenous and exogenous NO exert a protective role in experimental hepatic I/R injury, the mechanisms of the beneficial effect of the two sources of NO are different.

Topics: Alanine Transaminase; Animals; Dietary Supplements; Endothelins; Hyaluronic Acid; Liver; Male; Malondialdehyde; Nitric Oxide; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Statistics, Nonparametric; Superoxides

Hind limb ischemia-reperfusion (I/R) injury increases gut permeability, and resultant endotoxemia is associated with an amplified systemic inflammatory response syndrome leading to multiple organ dysfunction syndrome. We studied the potential role of recombinant bactericidal/permeability-increasing protein (rBPI(21) ), a novel antiendotoxin therapy, in modulating endotoxin-enhanced systemic inflammatory response syndrome in hind limb I/R injury.. In this prospective, randomized, controlled, experimental animal study, 48 male Wistar rats, weighing 300 to 350 g, were randomized to a control group (sham) and five groups undergoing 3 hours bilateral hind limb ischemia with 2 hours reperfusion (I/R) (n = 8 per group). The control and untreated I/R groups received thaumatin, a control-protein preparation, at 2 mg/kg. Treatment groups were administered rBPI(21) intravenously at 1, 2, or 4 mg/kg body weight at the beginning of reperfusion; an additional group was administered rBPI(21) intravenously at 2 mg/kg after 1 hour of reperfusion. Plasma interleukin-6 concentration was estimated by bioassay as a measure of systemic inflammation. Plasma endotoxin concentration was determined by use of an amebocyte lysate chromogenic assay. Crossreactive immunoglobulin G and M antibodies to the highly conserved inner core region of endotoxin were measured by use of an enzyme-linked immunosorbent assay. The lung tissue wet-to-dry weight ratio and myeloperoxidase concentration were used as markers of edema and neutrophil sequestration, respectively.. I/R provoked highly significant elevation in plasma interleukin-6 concentrations (1351.20 pg/mL [860.16 - 1886.40 pg/mL]) compared with controls (125.32 pg/mL [87.76-157.52 pg/mL; P <.0001]), but treatment with rBPI(21) 2 mg/kg at onset of reperfusion (715.89 pg/mL [573.36-847.76 pg/mL]) significantly decreased interleukin-6 response compared with the nontreatment group ( P <.016). I/R increased plasma endotoxin concentrations significantly (21.52 pg/mL [6.20-48.23 pg/mL]), compared with control animals (0.90 pg/mL [0.00-2.30 pg/mL; P <.0001]), and treatment with rBPI(21) 4 mg/kg at reperfusion significantly decreased endotoxemia (1.30 pg/mL [1.20-2.20 pg/mL]), compared with the untreated group ( P <.001). The lung tissue myeloperoxidase level was significantly increased in the untreated I/R group (208.18% [128.79%-221.81%]), compared with in controls (62.00% [40.45%-80.92%; P <.0001]), and attenuated in those treated with rBPI(21) 2 mg/kg (129.54% [90.49%-145.78%; P <.05]). Data represent median and interquartile range, comparisons made with the nonparametric Mann-Whitney U test.. These findings show that hind limb ischemia-reperfusion injury is associated with endotoxemia, elevations in plasma interleukin-6, and pulmonary leukosequestration. Treatment with rBPI(21) after ischemia reduces endotoxemia, the interleukin-6 response, and attenuates pulmonary leukosequestration in response to hind limb reperfusion injury.

Topics: Animals; Antimicrobial Cationic Peptides; Blood Proteins; Endotoxins; Hindlimb; Interleukin-6; Lung; Male; Membrane Proteins; Peroxidase; Rats; Rats, Wistar; Recombinant Proteins; Reperfusion Injury; Systemic Inflammatory Response Syndrome

The induction of stress response (heat shock) proteins (HSPs) is a highly conserved response that protects many cell types from diverse physiological and environmental stressors. We tested the hypothesis that the induction of HSPs is protective in experimental renal ischemia/reperfusion injury.. The effect of prior heat stress was examined in a rat model of renal ischemia. Postischemic renal function, histopathology, myeloperoxidase activity, and mortality were determined in hyperthermia and sham hyperthermia groups.. HSP84, HSP70, and HSP22 mRNA were increased after eight minutes but not four minutes of hyperthermia. The induction of HSP84 and HSP70 was blocked by pretreatment with quercetin. Improvement in renal function, mortality, and histologic abnormalities was seen with eight minutes of hyperthermia six hours before ischemia. Protection was dependent on the timing of ischemia relative to heat stress and was not observed when HSPs were not induced. Postischemic increases in renal myeloperoxidase activity were markedly attenuated in the hyperthermia compared with the sham hyperthermia group.. Endogenous protective mechanisms may be important in renal ischemia/reperfusion injury.

Topics: Animals; Blood Urea Nitrogen; Heat-Shock Proteins; Hot Temperature; HSP20 Heat-Shock Proteins; HSP70 Heat-Shock Proteins; Kidney; Male; Muscle Proteins; Peroxidase; Quercetin; Rats; Rats, Sprague-Dawley; Reperfusion Injury; RNA, Messenger

To determine whether parenteral feeding (IV-TPN) influences the local and systemic response to an intestinal insult.. Parenteral feeding increases ICAM-1 expression and attracts neutrophils (PMNs) to the intestine compared with enterally fed animals. Because the gut is a priming bed for PMNs, the authors hypothesized that IV-TPN may affect organ injury after gut ischemia-reperfusion (I/R).. Mice were randomized to chow, IV-TPN, intragastric TPN, or complex enteral diet for 5 days' feeding. In experiment 1, 162 mice underwent 15 or 30 minutes of gut I/R, and death was recorded at 72 hours. In experiment 2, 43 mice underwent 15 minutes of gut ischemia and permeability was measured by 125I-labeled albumin at 3 hours after reperfusion. Lung PMN accumulation was measured by myeloperoxidase assay. In experiment 3, albumin leak was tested in the complex enteral diet group (n = 5) and the intragastric TPN group (n = 5) after 30 minutes of gut ischemia and 1 hour of reperfusion.. In experiment 1, enteral feeding significantly reduced the death rate compared with IV-TPN after 15 minutes of I/R. After 30 minutes of gut ischemia, the IV-TPN and intragastric TPN groups showed a higher death rate than the chow and enteral diet groups. In experiment 2, IV-TPN significantly increased pulmonary and hepatic 125I albumin leak compared with enteral feeding without increasing pulmonary myeloperoxidase levels. In experiment 3, there were no differences in 125I albumin leak between the complex enteral diet and intragastric TPN groups.. Enteral feeding reduced the death rate and organ permeability after 15 minutes of ischemia. However, prolonged ischemia (30 minutes) eliminated any benefits of intragastric TPN on survival.

Topics: Animals; Capillary Permeability; Enteral Nutrition; Intestines; Leukocytes, Mononuclear; Mice; Mice, Inbred ICR; Parenteral Nutrition, Total; Peroxidase; Random Allocation; Reperfusion Injury; Time Factors

Activation of the cysteine protease calpain has been implicated in renal ischemia/reperfusion (I/R) injury. The aim of this study was to investigate the effects of calpain inhibitor-1 (Cal I-1) in an in vivo model of renal I/R injury.. Male Wistar rats were administered Cal I-1 (10 mg/kg, IP) 30 minutes before undergoing bilateral renal ischemia (45 minutes) followed by reperfusion (6 hours). Plasma concentrations of urea, creatinine, Na(+), gamma-glutamyl transferase (gamma GT), aspartate aminotransferase (AST) and urinary Na(+), glutathione S-transferase (GST), and N-acetyl-beta-D-glucosaminidase (NAG) were measured for the assessment of renal dysfunction and I/R injury. Creatinine clearance (C(Cr)) and fractional excretion of Na(+) (FE(Na)) were used as indicators of glomerular and tubular function, respectively. Kidney myeloperoxidase (MPO) activity and malondialdehyde (MDA) levels were measured for assessment of neutrophil infiltration and lipid peroxidation, respectively. Renal sections were used for histologic grading of renal injury and for immunohistochemical localization of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2).. Cal I-1 significantly reduced I/R-mediated increases in urea, creatinine, gamma GT, AST, NAG, and FE(Na) and significantly improved C(Cr). Cal I-1 also significantly reduced kidney MPO activity and MDA levels. Cal I-1 also reduced histologic evidence of I/R-mediated renal damage and caused a substantial reduction in the expression of iNOS and COX-2, both of which involve activation of nuclear factor-kappa B (NF-kappa B).. : These results suggest that Cal I-1 reduces the renal dysfunction and injury associated with I/R of the kidney. We suggest that the mechanism could involve the inhibition of I/R-mediated activation of NF-kappa B.

Topics: Acetylglucosaminidase; Acute Kidney Injury; Anesthesia; Animals; Aspartate Aminotransferases; Cyclooxygenase 2; Cysteine Proteinase Inhibitors; gamma-Glutamyltransferase; Glutathione Transferase; Glycoproteins; Immunohistochemistry; Isoenzymes; Kidney Glomerulus; Male; Malondialdehyde; NF-kappa B; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Oligopeptides; Peroxidase; Prostaglandin-Endoperoxide Synthases; Rats; Rats, Wistar; Reperfusion Injury; Serine Proteinase Inhibitors

We previously demonstrated in rats and mice that agonists of A(2A)-adenosine receptors (A(2A)-ARs) reduce renal injury following ischemia-reperfusion. We now extend these studies and examine the effects of ATL-146e (formerly DWH-146e), an A(2A)-AR agonist, and rolipram, a type IV phosphodiesterase (PDE 4) inhibitor, on murine renal injury following ischemia-reperfusion.. C57BL/6 mice were treated with rolipram, ATL-146e, or both compounds combined and were subjected to renal ischemia for 32 minutes and reperfusion for 24 to 48 hours. In vitro studies were performed on suspended and adhering human neutrophils.. Continuous delivery of rolipram or ATL-146e during reperfusion reduced renal injury in a dose-dependent manner. Maximal protection was observed when ATL-146e was infused for six hours during reperfusion. Elevated plasma creatinine and myeloperoxidase activity produced by ischemia-reperfusion were reduced by rolipram (0.1 ng/kg/min) and ATL-146e (10 ng/kg/min) by up to approximately 60% and 70%, respectively. Co-infusion of both compounds produced a maximum reduction of plasma creatinine of approximately 90% and myeloperoxidase activity. In vitro studies on suspended and adhering human neutrophils demonstrated that selective stimulation of A(2A)-ARs by ATL-146e increased cAMP accumulation, reduced oxidative activity of activated neutrophils, and decreased activated neutrophil adherence. These responses were potentiated by rolipram.. We conclude that the combined infusion of ATL-146e and rolipram leads to enhanced renal tissue protection from ischemia-reperfusion by mechanisms that may include reduced neutrophil adherence/recruitment and release of reactive oxygen species.

Topics: 3',5'-Cyclic-AMP Phosphodiesterases; Acute Kidney Injury; Animals; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Cyclic Nucleotide Phosphodiesterases, Type 4; Cyclohexanecarboxylic Acids; Dose-Response Relationship, Drug; Drug Therapy, Combination; Humans; Mice; Mice, Inbred C57BL; Neutrophils; Peroxidase; Phosphodiesterase Inhibitors; Purinergic P1 Receptor Agonists; Purines; Reactive Oxygen Species; Receptor, Adenosine A2A; Receptors, Purinergic P1; Reperfusion Injury; Respiratory Burst; Rolipram

Leukocytes play a key role in ischemia-reperfusion-induced tissue injuries. It has been suggested that blocking the Na+/H+ exchanger improves ischemic injuries such as stroke. In this study, we investigated the effect of the Na+/H+ exchanger inhibitor SM-20220 (N-[aminoiminomethyl]- 1-methyl-1H-indole-2-carboxamide methanesulfonate) on leukocyte-endothelial cell interactions during ischemia-reperfusion. SM-20220 (0.3-1.0 mg/kg i.v.) given after ischemia significantly attenuated the leukocyte adhesion in the mesenteric postcapillary venules that was induced by transient superior mesenteric artery occlusion. At 60 min after reperfusion, the numbers of adherent leukocytes in groups treated with vehicle or SM-20220 (0.3 mg/kg) were 15.1+/-2.9 cells/100 microm/3 min and 3.0+/-0.7 cells/100 microm/3 min (p < 0.01), respectively. In a transient middle cerebral artery occlusion model, i.v. infusion of SM-20220 (0.4 mg/kg per hour) for 1 h, beginning 1 h after the start of occlusion, significantly reduced both the infarct size and the increase in brain myeloperoxidase activity, compared with the vehicle group (p < 0.01 and p < 0.05, respectively). In summary, this is the first evidence that the leukocyte adhesion to the endothelium that is induced by ischemia-reperfusion is attenuated by the inhibition of Na+/H+ exchanger activity in vivo. Our results suggest that Na+/H+ exchanger inhibitors may prevent ischemia-reperfusion injuries such as stroke partly through the attenuation of leukocyte-endothelial cell interactions.

Topics: Amides; Animals; Cell Adhesion; Endothelium, Vascular; Indoles; Infarction, Middle Cerebral Artery; Leukocytes; Male; Mesentery; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Sodium-Hydrogen Exchangers

The combined application of exogenous surfactant and inhaled nitric oxide was evaluated for prevention of ischemia-reperfusion injury of the lung.. Left lungs were selectively perfused in 18 minipigs in situ with cold preservation solution. After 90 min of warm ischemia, the lungs were reperfused and the right pulmonary artery and bronchus were ligated (control group, n=6). Exogenous surfactant was instilled via bronchoscopy during ischemia (surfactant group, n=6). In a third group, surfactant was applied, followed by administration of inhaled nitric oxide (surfactant+NO group, n=6). Hemodynamic and respiratory parameters were recorded for 7 hr, and bronchoalveolar lavage fluid (BALF) was obtained before and after reperfusion for measurement of surface tension, small aggregate/large aggregate ratio, protein and phospholipid contents, and a differential cell count.. Control group animals survived for 3.7+/-1.4 hr. In both surfactant-treated groups, five out of six animals survived the observation period (P<0.001). Dynamic compliance of the lung was decreased in control animals (P<0.001). In the surfactant+NO group, arterial PO2 was higher than in both other groups (P<0.001). BALF cell count and histology showed reduced neutrophil infiltration in surfactant+NO-treated lungs. Surface tension assessed in BALF with a pulsating bubble surfactometer was severely impaired in control animals (gammamin, 14.82+/-9.95 mN/m), but maintained in surfactant-treated (gammamin, 1.11+/-0.56 mN/m) and surfactant+NO-treated animals (gammamin, 3.90+/-2.35 mN/m, P=0.02).. Administration of exogenous surfactant in lung reperfusion injury results in improved lung compliance. The addition of inhaled NO improves arterial oxygenation and reduces neutrophil extravasation compared with surfactant treatment alone.

Topics: Administration, Inhalation; Animals; Bronchoalveolar Lavage Fluid; Cell Count; Drug Therapy, Combination; Hemodynamics; Lung; Lung Compliance; Nitric Oxide; Peroxidase; Reperfusion Injury; Surface-Active Agents; Survival Rate; Swine, Miniature; Water

The objective of this study was to assess the role of inducible nitric oxide synthase (iNOS) in ischemia- and reperfusion (I/R)-induced liver injury. We found that partial hepatic ischemia involving 70% of the liver resulted in a time-dependent increase in serum alanine aminotransferase (ALT) levels at 1-6 h following reperfusion. Liver injury at 1, 3, and 6 h post-ischemia was not due to the infiltration of neutrophils as assessed by tissue myeloperoxidase (MPO) activity and histopathology. iNOS-deficient mice subjected to the same duration of ischemia and reperfusion showed dramatic and significant increases in liver injury at 3 but not 6 h following reperfusion compared to their wild type controls. Paradoxically, iNOS mRNA expression was not detected in the livers of wild type mice at any point during the reperfusion period and pharmacological inhibition of iNOS using L-N(6)(iminoethyl)-lysine (L-NIL) did not exacerbate post-ischemic liver injury at any time post-reperfusion. These data suggest that iNOS deficiency produces unanticipated genetic alterations that renders these mice more sensitive to liver I/R-induced injury.

Topics: Alanine Transaminase; Animals; Crosses, Genetic; Ischemia; Liver; Male; Mice; Mice, Inbred C57BL; Mice, Inbred Strains; Mice, Knockout; Neutrophils; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Reperfusion Injury

A central role for the polymorphonuclear leucocyte (PMN) in skeletal muscle ischaemia-reperfusion has been demonstrated by the observation that PMN depletion reduced local and remote pulmonary vascular permeability. This study investigated the role of recombinant soluble P-selectin glycoprotein ligand-immunoglobulin fusion protein (rPSGL-Ig), a P- and E-selectin antagonist, in moderating injury.. Mice underwent 2 h of hindlimb ischaemia and 3 h of reperfusion. Muscle and lung vascular permeability index (PI) was assessed by extravasation of (125)I-radiolabelled albumin. Lung myelo peroxidase (MPO) activity was also measured.. In mice treated with rPSGL-Ig 1 mg/kg before reperfusion (n = 12) muscle PI was reduced by 40 per cent, whereas it was moderated by 20 per cent in animals treated 30 min after reperfusion (n = 15). Lung PI in mice treated with rPSGL-Ig before (n = 12) and 30 min after (n = 15) reperfusion was reduced by over 99 and 98 per cent respectively. Lung MPO activity in mice treated with rPSGL-Ig before (n = 10) and 30 min after (n = 12) reperfusion was reduced by 68 and 58 per cent respectively. Treatment with rPSGL-Ig 1 h after reperfusion, or with m20ek.Fc 1 mg/kg (n = 9; negative control for rPSGL-Ig which is inactive for selectin binding) before reperfusion failed significantly to moderate local or remote organ injury.. Selectin blockade moderated local skeletal muscle and remote lung injury following hindlimb ischaemia--reperfusion. Significantly, delayed antiselectin therapy also decreased injury.

Topics: Animals; Hindlimb; Male; Membrane Glycoproteins; Mice; Mice, Inbred C57BL; Muscle, Skeletal; Permeability; Peroxidase; Reperfusion Injury

Few studies have pointed out the relationship between ischemia-reperfusion (IR) injury and the coagulation system. Antithrombin III (AT) has anti-inflammatory effects in IR injury. We investigated the effect of AT supplementation on renal IR injury in rats achieved by clamping of the left renal pedicle for 60 min and subsequent 24-h reperfusion after right nephrectomy. Sprague-Dawley rats were divided into three groups: sham-operated (no IR injury), ischemic controls, and an AT-treated group (250 U/kg before reperfusion). Creatinine values, tissue malondialdehyde (MDA) levels, myeloperoxidase (MPO) activity, and histopathological damage were investigated after 24 h of reperfusion. In addition, the 7-day survival rates in each group were evaluated. Creatinine and MDA levels and MPO activity were significantly elevated and histopathological damage was more severe in controls than in the sham group (P<0.05). Creatinine and MDA levels and MPO activity were significantly lower and there was less histopathological damage in the AT group than in controls. Accumulation of lipid peroxidation products and neutrophils were significantly inhibited by AT treatment. We conclude that AT may attenuate renal IR injury in rats.

Topics: Acute Kidney Injury; Animals; Antithrombin III; Creatinine; Kidney; Lipid Peroxidation; Male; Malondialdehyde; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Serine Proteinase Inhibitors

The small intestine is highly sensitive to oxygen free radical-induced injury. Post-ischemic intestinal tissue damage appears to be due to the formation of oxygen radicals. Free radical initiated lipid peroxidation (LP) following intestinal ischemia/reperfusion (I/R) may disrupt mucosal integrity. Indirectly, the radicals trigger the accumulation of neutrophils within the affected tissue, initiating inflammatory processes that lead to severe mucosal lesions. In the present study we investigated the effect of pentoxifylline (PTX), a potent inhibitor of tumour necrosis factor production, on I/R induced intestinal injury. Wistar albino rats were divided into four groups: (1) Sham operation (S); (2) Sham operation + PTX (50 mg/kg i.v.) (S + PTX); (3) 1 h ischemia + 2 h reperfusion (I/R); and (4) I/R + PTX. Animals were sacrificed at the end of the reperfusion period and ileum samples were obtained. Malondialdehyde (MDA) levels, an end product of LP, glutathione (GSH) levels, a key antioxidant, and myeloperoxidase (MPO) activity (an index of polymorphonuclear neutrophils) stimulation, were determined in ileum homogenates. The results of the present study indicate that ischemia/reperfusion results in a significant increase in MDA content and MPO activity with a significant decrease in GSH content. Treatment with PTX returns these biomarkers to control values. A mechanism of this protective effect may involve inhibition of neutrophil oxidative burst.

Topics: Animals; Biomarkers; Free Radical Scavengers; Free Radicals; Glutathione; Ileum; Intestinal Mucosa; Intestine, Small; Lipid Peroxidation; Malondialdehyde; Neutrophils; Pentoxifylline; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Respiratory Burst

Cytokine production is a critical component of ischemia/reperfusion (IR) injury. In the liver, Kupffer cells produce cytokines and chemokines (i.e., cytokines with chemoattractant properties) that are important mediators in neutrophil recruitment and subsequent hepatocellular injury. Therefore, the role of Kupffer cells in chemokine production in hepatic IR injury was investigated.. Adult male C57BL/6 mice underwent 90 min of partial hepatic ischemia followed by various reperfusion times (i.e., 0, 1.5, 3, and 6 h). Gadolinium chloride (GC), which inhibits Kupffer cell activity, was administered to mice 48 and 24 h prior to ischemia. The control group received a corresponding volume of normal saline. Plasma levels of the cytokine macrophage inflammatory protein-2 (MIP-2), KC, and tumor necrosis factor (TNF)-alpha and liver mRNA were measured. Liver injury was assessed by plasma level of alanine transaminase (ALT) and histopathology.. A reperfusion time-dependent liver injury occurred as indicated by increased levels of plasma ALT and histopathology. The injury was associated with increased plasma TNF-alpha, MIP-2, and KC and their hepatic mRNA expression and neutrophil infiltration into ischemic lobes of the liver. GC treatment significantly reduced the number of Kupffer cells as determined by the immunostained liver tissue sections. The extent of liver injury significantly decreased in GC-treated mice that were associated with decreased levels of plasma ALT, TNF-alpha, MIP-2, and KC and neutrophil infiltration.. This study suggests that Kupffer cells are major contributors to cytokine production in hepatic IR and their modulation may serve as a potential target for therapeutic intervention.

Topics: Alanine Transaminase; Animals; Anti-Inflammatory Agents; Chemokine CXCL1; Chemokine CXCL2; Chemokines; Chemokines, CXC; Chemotactic Factors; Gadolinium; Gene Expression; Growth Substances; Immunohistochemistry; Intercellular Signaling Peptides and Proteins; Kupffer Cells; Liver; Liver Diseases; Male; Mice; Mice, Inbred C57BL; Neutrophils; Peroxidase; Reperfusion Injury; RNA, Messenger; Tumor Necrosis Factor-alpha

Adenosine attenuates skeletal muscle reperfusion injury, but its short half-life in vivo limits potential therapeutic benefits. The aim of this study was to ascertain whether inosine, a stable adenosine metabolite, modulates skeletal muscle reperfusion injury.. C57BL/6 mice were randomized (8-10 per group) to six groups: time controls; inosine (100 mg/kg) before anesthesia; 2 h of bilateral tourniquet hindlimb ischemia; I/R (2 h of bilateral tourniquet hindlimb ischemia, 3 h of reperfusion); inosine (100 mg/kg) before I/R; drug vehicle before I/R. Serum tumor necrosis factor (TNF)-alpha and macrophage inflammatory protein (MIP)-2 were measured before ischemia and at the end of reperfusion. Tissue edema was determined by wet/dry weight ratios. Tissue leucosequestration was assessed by the myeloperoxidase (MPO) content.. At the end of reperfusion, inosine pretreatment resulted in lower MPO levels in muscle (P = 0.02) and lung (P = 0.0002) than saline pretreatment. Similarly, muscle (P = 0.04) and lung (P = 0.02) wet/dry ratios were significantly reduced with inosine but not with saline pretreatment. At the end of reperfusion, serum proinflammatory cytokine levels (TNF-alpha and MIP-2) were significantly reduced (P < 0.05) compared to preischemia levels following inosine pretreatment but not saline pretreatment. Ischemia alone did not alter any of the parameters assessed.. These findings demonstrate that pretreatment with inosine attenuates the local and systemic proinflammatory responses associated with skeletal muscle reperfusion injury.

Topics: Animals; Chemokine CXCL2; Chemokines; Disease Models, Animal; Edema; Inosine; Lung; Male; Mice; Mice, Inbred C57BL; Muscle, Skeletal; Oxidative Stress; Peroxidase; Pulmonary Edema; Reperfusion Injury; Tourniquets; Tumor Necrosis Factor-alpha

We examined the role of endothelin in ischaemia/reperfusion injury in skeletal muscle, using the endothelin receptor antagonist Bosentan. In the rat hindlimb tourniquet ischaemia model, one hindlimb was rendered ischaemic for 2 h at 36 degrees C, then blood flow was re-established for either 24 h to assess muscle survival or 1.5 h for a study of capillary perfusion. In the first set of rats, the gastrocnemius muscle was removed from the postischaemic limb and assessed for viability histochemically using the nitro blue tetrazolium stain. Tissue water content (a measure of oedema) and myeloperoxidase activity (a measure of neutrophil accumulation) were also assessed in the ischaemic muscle, the contralateral non-ischaemic muscle and the lungs. In the second set of rats, the hind limb was infused with India ink after 2-h ischaemia and 1.5-h reperfusion and the muscle was harvested, fixed and cleared. In control rats, muscle viability was 17+/-2% (S.E.M.). In rats treated with Bosentan (10 mg/kg, i.p.) 30 min before release of the tourniquet, muscle viability (48+/-7%) was significantly increased compared to the control group (P<0.01). Bosentan treatment had no significant effect on tissue water content or myeloperoxidase activity in the ischaemic muscle, the contralateral non-ischaemic muscle or the lung. Immunoreactive endothelin levels in serum increased to a peak at 90 min of reperfusion and returned to control levels by 24-h reperfusion. India ink studies demonstrated a significantly increased functional capillary density in postischaemic Bosentan-treated muscles compared with postischaemic control muscles (P<0.05). These results suggest that endothelin plays an important role in the necrosis which results from a period of ischaemia and reperfusion in skeletal muscle, by mediating a decrease in postischaemic microvascular perfusion.

Topics: Animals; Blood Pressure; Bosentan; Carbon; Cell Survival; Coloring Agents; Dose-Response Relationship, Drug; Endothelin Receptor Antagonists; Endothelins; Hindlimb; Male; Muscle, Skeletal; Perfusion; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sulfonamides; Time Factors; Water

We examined the effect of adenovirus-mediated transtracheal transfer of the human interleukin 10 (hIL-10) gene on lung ischemia-reperfusion (IR) injury, which is the insult due to hypothermic preservation plus graft reperfusion, and posttransplant lung function in Lewis rat lungs. Thirty rats were divided into 6 groups (n = 5). Groups 1 and 4 received 5 x 10(9) PFU of Ad5E1RSVhIL-10, groups 2 and 5 received 5 x 10(9) PFU of Ad5BGL2 ("empty" vector), and groups 3 and 6 received 3% sucrose (diluent). After 24 hr of in vivo transfection, lungs were stored at 4 degrees C (cold ischemic time, CIT) for 6 hr (groups 1-3) or 24 hr (groups 4-6) before transplantation. After 2 hr of reperfusion, lung function was assessed by oxygenation (FIO2, 1.0), airway pressure (AwP), and wet-to-dry (W/D) weight ratios. Rat tumor necrosis factor alpha (rTNF-alpha), interferon gamma (IFN-gamma), IL-10, and hIL-10 were measured in graft tissue and recipient plasma by ELISA and detected by immunohistochemistry (IHC). Partial pressure of oxygen (PaO2) levels in the hIL-10 group (6 hr of CIT) were higher than in empty vector and diluent groups (PaO2, 530 +/- 23 vs. 387 +/- 31 and 439 +/- 27 mmHg, respectively, p < 0.05). IL-10 rats after 24 hr of CIT showed higher PaO2 levels (260 +/- 29 mmHg) than empty vector (96 +/- 24 mmHg) or diluent (133 +/- 10 mmHg) lungs (p < 0.05). AwP and W/D ratios were reduced in hIL10 lungs (p < 0.05) compared with the other groups. rTNF-alpha and INF-gamma were reduced in tissue and plasma in groups 1 and 4 (p < 0.05). rIL-10 was reduced in the tissue of hIL-10 lungs (p < 0.05). IHC showed equal distribution of cytokines in tissue and abundant transgene expression in large and small airway epithelium in hIL-10 lungs.

Topics: Adenoviridae; Animals; Enzyme-Linked Immunosorbent Assay; Gene Transfer Techniques; Genetic Therapy; Immunohistochemistry; Interferon-gamma; Interleukin-10; Lung; Lung Transplantation; Male; Oxygen; Peroxidase; Random Allocation; Rats; Rats, Inbred Lew; Reperfusion Injury; Time Factors; Trachea; Transfection; Tumor Necrosis Factor-alpha

Substitution of the nitric oxide- (NO-) pathway improves early graft function following lung transplantation. We previously demonstrated that 8-Br-cGMP (second messenger of NO) to the flush solution and tetrahydrobiopterin (BH4, coenzyme of NO synthase) given as additive during reperfusion improve post-transplant graft function. In the present study, the combined treatment with 8-Br-cGMP and BH4 was evaluated.. Unilateral left lung transplantation was performed in weight matched outbred pigs (24-31 kg). In group I, grafts were preserved for 30 h (n=5). 8-Br-cGMP (1mg/kg) was added to the flush solution (Perfadex, 1.5l, 1 degrees C) and BH4 (10mg/kg/h) was given to the recipient for 5h after reperfusion. In group II, lungs were transplanted after a preservation time of 30 h (n=3) and prostaglandin E(1) (250 g) was given into the pulmonary artery (PA) prior to flush. In all recipients 1h after reperfusion the contralateral right PA and bronchus were ligated to assess graft function only. Survival time after reperfusion, extravascular lung water index (EVLWI), hemodynamic variables, and gas exchange (PaO(2)) were assessed during a 12h observation period.. All recipients in group I survived the 12h assessment, whereas none of the group II animals survived more than 4h after reperfusion with a rapid increase of EVLWI up to 24.8+/-6.7 ml/kg. In contrast, in group I EVLWI reached up to 8.9+/-1.5 ml/kg and returned to nearly normal levels at 12h (6.1+/-0.8 ml/kg). In two animals of group I the gas exchange deteriorated slightly. The other three animals showed normal arterial oxygenation over the entire observation time.. Our data indicate that the combined substitution of the NO pathway during preservation and reperfusion reduces ischemia/reperfusion injury substantially and that this treatment even allows lung transplantation after 30 h preservation in this model.

Topics: Animals; Biopterins; Cell Movement; Coenzymes; Cyclic GMP; Extravascular Lung Water; Graft Survival; Hemodynamics; Infusions, Intravenous; Lipid Peroxidation; Lung; Lung Transplantation; Neutrophils; Nitric Oxide Synthase; Organ Preservation; Organ Preservation Solutions; Peroxidase; Pulmonary Gas Exchange; Reperfusion Injury; Swine; Thiobarbituric Acid Reactive Substances; Time Factors

Treatment with hyperbaric O2 (HBO) ameliorates ischemia-reperfusion (I/R) injury. Since tumor necrosis factor-alpha (TNF-alpha) plays an important role in I/R injury, we hypothesized that the effect of HBO in I/R injury may be due to its ability to inhibit TNF-alpha production. In this study, one group of rats received HBO during 60 min of ischemia (HBO group, n = 9), while control rats endured the same procedure but did not receive HBO (non-HBO, n = 9). A group of sham-operated control rats (SHAM, n = 6) underwent laparotomy without occlusion of the artery and HBO treatment. Intestinal I/R led to an increase in serum TNF-alpha concentration to [mean (SEM)] 165 (32) pg/ml (P < 0.01 vs SHAM rats). HBO attenuated this increase [34 (9) pg/ml; P<0.05 vs non-HBO group]. Intestinal I/R also resulted in a marked increase in lung myeloperoxidase content [0.62 (0.04) U/g vs 0.17 (0.02) U/g of SHAM rats, P<0.01]. HBO suppressed this increase [0.40 (0.04) U/g, P<0.05 vs non-HBO rats]. HBO ameliorated the injury to the intestine and lung. The number of neutrophils sequestered in the lung was reduced in HBO rats compared to non-HBO rats [6.4 (0.9) neutrophils/per oil field and 10.9 (2) neutrophils/per oil field, respectively; P < 0.05]. These findings demonstrate that HBO inhibits TNF-alpha production during intestinal I/R, and this reduced TNF-alpha production may be attributed to the beneficial effects of HBO.

Topics: Acute Disease; Animals; Hyperbaric Oxygenation; Intestines; Lung; Male; Microvilli; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Specific Pathogen-Free Organisms; Tumor Necrosis Factor-alpha

This study investigates the role of neutrophils in ischemia-induced aspermatogenesis in the mouse. Previous studies in the rat have demonstrated that ischemia-inducing testicular torsion followed by torsion repair and reperfusion resulted in germ cell-specific apoptosis. This was correlated with an increase in neutrophil adhesion to subtunical venules, an increase in reactive oxygen species, and increased expression of several apoptosis-associated molecules. In the present investigation, wild-type C57BL/6 mice were subjected to various degrees and duration of testicular torsion. A torsion of 720 degrees for 2 h caused disruption of the seminiferous epithelium and significantly reduced testis weight and daily sperm production. An immunohistochemical method specific for apoptotic nuclei indicated that these effects were due to germ cell-specific apoptosis. An increase in myeloperoxidase (MPO) activity and an increase in the number of neutrophils adhering to testicular subtunical venules after torsion repair/reperfusion demonstrated an increase in neutrophil recruitment to the testis. In contrast, E-selectin knockout mice and wild-type mice rendered neutropenic showed a significant decrease in neutrophil recruitment as evidenced by MPO activity and microscopic examination of subtunical venules. Importantly, germ cell-specific apoptosis was also reduced. Thus, germ cell-specific apoptosis is observed after ischemia/reperfusion of the murine testis, and this apoptosis is directly linked to the recruitment of neutrophils to subtunical venules. Endothelial cell adhesion molecules, particularly E-selectin, play an important role in mediating this pathology.

Topics: Animals; Apoptosis; Cell Adhesion; E-Selectin; Immunohistochemistry; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutropenia; Neutrophils; Organ Size; Peroxidase; Reactive Oxygen Species; Reperfusion Injury; Seminiferous Epithelium; Testicular Diseases; Testis; Torsion Abnormality

Despite the current interest in thrombolytic therapy for acute stroke, ischemia-reperfusion injury remains a potentially hazardous complication. The complement system is thought to play a major role in initiating some of the inflammatory events occurring in the reperfusion injury. This study was conducted to explore the effect of C 1 esterase inhibitor (C 1 INH) on the reperfusion injury in rat middle cerebral artery (MCA) occlusion-reperfusion model.. Twenty-nine male Wistar rats were used. Intraluminal MCA occlusion was performed for 60 minutes. Just before the reperfusion, C 1 INH(50 IU/kg, C 1 INH group, n = 15) or saline (control group, n = 14) was administrated. Forty-eight hours after the reperfusion, infarct volume and myeloperoxidase(MPO) activity of the brain were evaluated.. Infarct volume and MPO activity were significantly smaller in the C 1 INH group(86.5 +/- 76.8 mm3, 0.38 +/- 0.30 U/g) than in control group(179 +/- 92.8 mm3, 1.37 +/- 0.46 U/g) (p < 0.01).. The results of this study provided the first evidence that C 1 INH reduced polymorphonuclear leukocytes(PMN) accumulation and reperfusion damage in the brain.

Topics: Animals; Brain Ischemia; Complement C1 Inactivator Proteins; Male; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Recent evidence strongly suggests that endothelins (ETs) play an important role in the regulation of blood-brain barrier (BBB) functions. The aim of the present study was to evaluate the role of ETs on edema formation and BBB permeability change after cerebral ischemia/reperfusion.. We examined the brain tissue ET-1 content and evaluated the time and dose response of the therapeutic effects of the specific ET type A receptor (ET(A)) antagonist, S-0139, on brain edema formation, development of infarction, and disruption of BBB after 1 hour of middle cerebral artery occlusion (MCAO) in rats.. After 1-hour MCAO and reperfusion, the brain ET-1 content did not change during the first 3 hours, increased at 6 hours, and rose almost continuously over 48 hours in the ischemic region as well as in the ischemic rim. Rats infused with S-0139 (0.03 to 1.0 mg/kg per hour) during reperfusion showed dose-dependent and significant attenuation of the increase in brain water content 24 hours after reperfusion. When the infusion of S-0139 was begun after 10 minutes and 1 hour of reperfusion, the brain edema formation and infarct size were significantly attenuated. Furthermore, posttreatment with S-0139 significantly attenuated the increased Evans blue dye-quantified albumin extravasation and improved the mortality of animals after cerebral ischemia/reperfusion.. Our data demonstrate that infusion with S-0139, an ET(A) antagonist, results in significant reduction of brain injury and plasma extravasation after transient MCAO. Thus, ETs may contribute to cerebral ischemia/reperfusion injury at least partly by increasing the BBB permeability via ET(A)s.

Topics: Animals; Blood-Brain Barrier; Brain; Brain Chemistry; Brain Edema; Caffeic Acids; Disease Models, Animal; Dose-Response Relationship, Drug; Endothelin Receptor Antagonists; Endothelin-1; Endothelins; Infarction, Middle Cerebral Artery; Ischemic Attack, Transient; Male; Neuroprotective Agents; Oleanolic Acid; Peroxidase; Rats; Rats, Wistar; Receptor, Endothelin A; Reperfusion Injury; Survival Rate; Time Factors; Water

Oxidative stress after ischemia/reperfusion of cardiac allografts leads to cytokine production. Bcl-2, an inhibitor of apoptosis, also has strong antioxidant properties. Caspase-3 is known to cleave bcl-2. This study tests the hypothesis that bcl-2 is downregulated while tumor necrosis factor-alpha (TNF-alpha) levels increase after cardiac transplantation. Furthermore, the use of caspase-3 inhibition was investigated as a strategy for preserving myocardial bcl-2 and mitochondrial cytochrome c after transplantation.. PVG-to-ACI rat heterotopic cardiac transplantations were performed in 4 groups designed with 30 minutes' ischemia and 4 or 8 hours of reperfusion (n=4 per group). Treatment consisted of DEVD-CHO 500 microgram IP per animal to donor and recipient 2 hours before transplantation and 250 microgram IC into allograft. Controls were treated with saline. Grafts were analyzed by reverse transcription-polymerase chain reaction for bcl-2 mRNA, by ELISA for TNF-alpha, for myeloperoxidase activity, and by Western blot for cytochrome c. In untreated groups, bcl-2 mRNA decreased significantly over time, whereas TNF-alpha increased significantly at 4 hours (P=0.003) and returned to baseline after 8 hours' reperfusion (P=NS compared with normal hearts). Treatment with caspase-3 inhibitor showed significant upregulation of bcl-2 mRNA expression after 4 and 8 hours of reperfusion (P<0.001 versus control), with a concomitant decrease in TNF-alpha to baseline levels. Myeloperoxidase activity in all groups was no different from that of normal hearts. Mitochondrial cytochrome c release increased in both control and treatment groups.. Bcl-2 is actively downregulated and TNF-alpha is upregulated in this model of cardiac allograft ischemia/reperfusion. Furthermore, the caspase-3 pathway is linked to this process, and blockade of caspase-3 can ameliorate reperfusion injury by upregulating bcl-2 and inhibiting TNF-alpha without affecting cytochrome c release.

Topics: Animals; Caspase 3; Caspase Inhibitors; Caspases; Cytochrome c Group; Enzyme Activation; Enzyme Inhibitors; Heart Transplantation; Male; Mitochondria; Myocardium; Oligopeptides; Oxidative Stress; Peroxidase; Proto-Oncogene Proteins c-bcl-2; Rats; Rats, Inbred Strains; Reperfusion Injury; RNA, Messenger; Transplantation, Homologous; Tumor Necrosis Factor-alpha; Up-Regulation

Interleukin-1 (IL-1) plays a role in mediating acute inflammation during ischemia-reperfusion (I/R) injury in the heart, which leads to both necrosis and apoptosis of cardiomyocytes. IL-1 receptor antagonist (IL-1ra) is known to inhibit the effects of IL-1alpha and IL-1beta, resulting in attenuated inflammatory injury, and to protect cells from IL-1beta-induced apoptosis in vitro. We hypothesized that IL-1ra overexpression would provide cardioprotection by reducing inflammation-mediated myocardial damage including apoptosis after I/R injury in vivo.. Rat hearts were transfected with human secreted-type IL-1ra gene by intracoronary infusion of Hemagglutinating Virus of Japan liposome and were heterotopically transplanted. IL-1ra overexpression in these hearts was confirmed by enzyme immunoassay and immunohistochemistry. Myocardial tolerance of the transplanted heart was evaluated with the use of a novel system in which the heart, existing within the recipient's abdomen, was given 30 minutes of ischemia by left coronary artery occlusion and 24 hours of reperfusion. Consequently, infarct size was decreased in IL-1ra-transfected hearts compared with control-transfected ones (26.9+/-3.2% versus 46.2+/-3.0%, P=0.001), corresponding to lower myocardial myeloperoxidase activity (2.20+/-0.69 versus 6.82+/-1.19 U/g wet wt, P<0.001) and decreased neutrophil infiltration in histological study. Terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling and DNA-laddering studies demonstrated that cardiomyocyte apoptosis was attenuated in IL-1ra-transfected hearts (21.4+/-3.3 versus 41.4+/-3.4%, P=0.002), correlating with reduced post I/R upregulation of Bax, Bak, and caspase-3.. IL-1ra introduced by gene transfection protected myocardium from I/R injury by attenuating the inflammatory response, which was associated with decreased apoptosis. This suggests a potentially important role of IL-1/IL-1ra in myocardial I/R injury and the value of IL-1ra-gene therapy for myocardial preservation.

Topics: Animals; Apoptosis; Disease Models, Animal; Gene Expression; Heart Transplantation; Humans; In Vitro Techniques; Inflammation; Interleukin 1 Receptor Antagonist Protein; Liposomes; Male; Myocardial Infarction; Myocardium; Peroxidase; Rats; Rats, Inbred Lew; Reperfusion Injury; Respirovirus; Sialoglycoproteins; Transfection

The effects of estrogen and ovariectomy on indexes of muscle damage after 2 h of complete hindlimb ischemia and 2 h of reperfusion were investigated in female Sprague-Dawley rats. The rats were assigned to one of three experimental groups: ovariectomized with a 17beta-estradiol pellet implant (OE), ovariectomized with a placebo pellet implant (OP), or control with intact ovaries (R). It was hypothesized that following ischemia-reperfusion (I/R), muscle damage indexes [serum creatine kinase (CK) activity, calpain-like activity, inflammatory cell infiltration, and markers of lipid peroxidation (thiobarbituric-reactive substances)] would be lower in the OE and R rats compared with the OP rats due to the protective effects of estrogen. Serum CK activity following I/R was greater (P < 0.01) in the R rats vs. OP rats and similar in the OP and OE rats. Calpain-like activity was greatest in the R rats (P < 0.01) and similar in the OP and OE rats. Neutrophil infiltration was assessed using the myeloperoxidase (MPO) assay and immunohistochemical staining for CD43-positive (CD43+) cells. MPO activity was lower (P < 0.05) in the OE rats compared with any other group and similar in the OP and R rats. The number of CD43+ cells was greater (P < 0.01) in the OP rats compared with the OE and R rats and similar in the OE and R rats. The OE rats had lower (P < 0.05) thiobarbituric-reactive substance content following I/R compared with the R and OP rats. Indexes of muscle damage were consistently attenuated in the OE rats but not in the R rats. A 10-fold difference in serum estrogen content may mediate this. Surprisingly, serum CK activity and muscle calpain-like activity were lower (P < 0.05) in the OP rats compared with the R rats. Increases in serum insulin-like growth factor-1 content (P < 0.05) due to ovariectomy were hypothesized to account for this finding. Thus both ovariectomy and estrogen supplementation have differential effects on indexes of I/R muscle damage.

Topics: Animals; Antigens, CD; Calpain; Creatine Kinase; Estrogens; Female; Glycogen; Hindlimb; Insulin-Like Growth Factor I; Lactic Acid; Leukosialin; Lipid Peroxidation; Muscle, Skeletal; Neutrophil Infiltration; Ovariectomy; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sialoglycoproteins; Thiobarbituric Acid Reactive Substances

Hepatic ischemia/reperfusion (I/R) results in tumor necrosis factor (TNF) release. Kupffer cells (KC) are one source of this TNF. This study investigates the effects of hepatic I/R combined with lipopolysaccharide (LPS) on the lung and liver injury that follow hepatic I/R and on hepatic release of TNF, epithelial neutrophil activating protein (ENA-78), and macrophage inflammatory protein-2 (MIP-2). The effects of these experimental conditions on TNF production by primary rat KC in vitro were also investigated. Rats were subjected to hepatic I/R alone, hepatic I/R + LPS, sham laparotomy alone, or sham laparotomy + LPS and pulmonary MPO, pulmonary microvascular permeability, hepatic neutrophil influx, hepatic injury, and hepatic TNF, ENA-78, and MIP-2 production were measured. These experiments demonstrated that hepatic I/R in conjunction with LPS results in a more severe lung and liver injury and increased hepatic TNF, ENA-78, and MIP-2 release. The effects of these experimental conditions on rat KC TNF production demonstrated that hepatic I/R + LPS results in a more significant release of TNF as compared to LPS alone or I/R alone. Hepatic I/R plus LPS results in a more severe lung and liver injury and is likely secondary to a more significant and prolonged release of TNF by KC. This may provide a mechanism for development of multiple organ system failure in some patients undergoing hepatic resection, hepatic transplantation, complex vascular operations, or in the setting of hypovolemic shock. Portal endotoxemia related to mesenteric venous congestion or other systemic insults may have a significant impact on post-operative complications and recovery in the setting of a local or global hepatic I/R injury.

Topics: Animals; Cells, Cultured; Chemokine CXCL2; Chemokine CXCL5; Chemokines; Chemokines, CXC; Interleukin-8; Ischemia; Kupffer Cells; Lipopolysaccharides; Liver; Lung; Lung Injury; Male; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

Even with excellent operative techniques, prolonged ischemic periods may cause unwanted results because of a complex mechanism called reperfusion injury. Various pharmacological and immunological agents have been used to prevent this type of injury. Another known way to diminish reperfusion injury is the gradual reperfusion of the ischemic tissues. In this study, the effect of a gradual increase in blood flow on ischemia-reperfusion injury of the skeletal muscle was investigated. The right hind limbs of 15 rats were partially amputated, leaving the femoral vessels intact. Preischemic femoral arterial blood flow was measured by using a transonic small-animal blood flowmeter (T106) in all animals. The rats were divided into three groups: Group I consisted of control rats; no ischemia was induced. Group II was the conventional clamp release group. Clamps were applied to the femoral vessels to induce 150 minutes of ischemia. The clamps were then released immediately and postischemic blood flow was measured. Group III was the gradual clamp release group. After 150 minutes of ischemia, clamps were released gradually at a rate so that the blood flow velocity would reach one fourth the mean preischemic value at 30 seconds, one half at 60 seconds, three fourths at 90 seconds, and would reach its preischemic value at 120 seconds. Total clamp release was allowed when blood flow was less than 1.5 fold of the preischemic values. Postoperatively the soleus muscles were evaluated histopathologically, and malonyldialdehyde and myeloperoxidase levels were measured. The mean preischemic blood flow was 13.6 +/- 2.24 ml per kilogram per minute in all groups. In the conventional release group, postischemic flow reached four to five fold its preischemic values (61.06 ml per kilogram per minute). Histopathology revealed more tissue damage in the conventional release group. Malondialdehyde and myeloperoxidase levels were also significantly lower in the gradual release group. Depending on histological and biochemical findings, a gradual increase in blood flow was demonstrated to reduce the intensity of ischemia-reperfusion injury in the soleus muscle of this animal model.

Topics: Animals; Blood Flow Velocity; Femoral Artery; Male; Malondialdehyde; Muscle, Skeletal; Oxygen; Oxygen Consumption; Peroxidase; Random Allocation; Rats; Rats, Sprague-Dawley; Reperfusion Injury

P-selectin-dependent leukocyte-endothelial cell adhesion has been implicated in the pathogenesis of ischemia/reperfusion (I/R) injury in several vascular beds, including the gut. Because platelet-endothelial (P/E) cell adhesion also occurs in postischemic venules, the possibility exists that the expression of P-selectin on the surface of platelets that are adherent to venular endothelial cells may mediate the leukocyte recruitment elicited by I/R. P-selectin expression [dual radiolabeled monoclonal antibody (MAb) technique] and neutrophil accumulation [myeloperoxidase (MPO) activity] were measured in the postischemic small intestine of untreated rats and rats treated with either antiplatelet serum (APS) or MAbs directed against either P-selectin, GPIIb/IIIa, or fibrinogen. The increases in P-selectin expression and tissue MPO normally elicited by I/R were significantly attenuated in the different treatment groups, suggesting that I/R-induced neutrophil recruitment is a platelet-dependent, P-selectin-mediated process. Intravital microscopy was then employed to examine this process relative to leukocyte-endothelial cell adhesion in postischemic rat mesenteric venules. The recruitment of adherent and emigrated leukocytes after I/R was attenuated by pretreatment with a MAb against, either P-selectin, GPIIb/IIIa, or fibrinogen, as well as an Arg-Gly-Asp peptide. Whereas thrombocytopenia greatly blunted leukocyte emigration, it did not alter the leukocyte adherence response to I/R. These findings suggest that platelet-associated P-selectin contributes to the accumulation of leukocytes in postischemic tissue via a mechanism that alters transendothelial leukocyte migration.

Topics: Animals; Antibodies; Antibodies, Monoclonal; Blood Platelets; Cell Adhesion; Chemotaxis, Leukocyte; Fibrinogen; Immunoglobulin Fab Fragments; Leukocytes; Male; Mesenteric Arteries; Mesenteric Vascular Occlusion; Mesenteric Veins; Oligopeptides; P-Selectin; Peroxidase; Platelet Glycoprotein GPIIb-IIIa Complex; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Splanchnic Circulation

The objective of this study was to examine whether a decrease in neutrophil-mediated tissue injury using Fucoidin, a nontoxic neutrophil rolling inhibitor, would improve flap survival in an island flap model after ischemia-reperfusion. Myeloperoxidase activity (an indirect index of tissue neutrophil count) and malondialdehyde (an indicator of lipid peroxidation), the degree of neutrophil infiltration by direct counting, and macroscopic flap survival were assessed in the flap after arterial ischemia-reperfusion. Epigastric island skin flaps were elevated in 56 rats. The first group of 21 rats was subjected to 6 hours of arterial ischemia. The second group of 21 rats was subjected to 10 hours of arterial ischemia, and the rest of the rats were used as nonischemic controls (sham flaps). For inhibiting neutrophil rolling, a nontoxic polysaccharide agent-Fucoidin-was used. Each ischemic group was divided further into three subgroups: Subgroup I (control rats) received saline, subgroup II received 10 mg per kilogram Fucoidin, and subgroup III received 25 mg per kilogram Fucoidin before reperfusion. The results were evaluated as tissue neutrophil counts, tissue malondialdehyde content, tissue myeloperoxidase activity, and flap survival. Neutrophil counts and tissue myeloperoxidase activity were decreased significantly (p <0.001) in subgroup III, but lipid peroxidation by means of tissue malondialdehyde content was not affected by Fucoidin administration. The authors conclude that administration of Fucoidin before reperfusion can limit tissue injury apparently by inhibiting neutrophil rolling in a dose-dependent manner.

Topics: Animals; Fucose; Graft Survival; Malondialdehyde; Neutrophil Infiltration; Neutrophils; Peroxidase; Polysaccharides; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Surgical Flaps

Ischemia-reperfusion injury involves free radical generation and polymorphonuclear neutrophil chemotaxis. Trimetazidine is an anti-ischemic drug that restores the ability of the ischemic cells to produce energy and reduces the generation of oxygen-derived free radicals. We evaluated the effect of trimetazidine against ischemia-reperfusion injury after lung transplantation.. Rat single lung transplantation was performed in 3 experimental groups (n = 5): (1) the immediate transplantation group was defined as animals undergoing transplantation immediately after harvest without treatment; (2) the ischemic control group was defined as animals undergoing transplantation after 18 hours of cold (4 degrees C) ischemia without treatment; and (3) the trimetazidine-treated group was defined as animals undergoing transplantation after 18 hours of cold (4 degrees C) ischemia and donor and recipient treatment with 5 mg/kg intravenous trimetazidine 10 minutes before harvest and reperfusion, respectively. All donor lungs were flushed with low-potassium dextran-glucose solution. After 2 hours of reperfusion, oxygenation was measured, and lung tissue was frozen and assessed for adenosine triphosphate content, myeloperoxidase activity, and thiobarbituric acid-reactive substances. Peak airway pressure was recorded throughout the reperfusion period.. The trimetazidine group showed significantly higher levels of adenosine triphosphate content (1.73 +/- 0.8 pmol vs 0.72 +/- 0.2 pmol [ischemic control], P =.008), better oxygenation (238.82 +/- 113.9 mm Hg vs 89.39 +/- 14.7 mm Hg [ischemic control], P =.008), and reduced lipid peroxidation (1.28 +/- 0.1 nmol/g vs 2.09 +/- 0.4 nmol/g [ischemic control], P =.008). Adenosine triphosphate levels of the trimetazidine group were comparable with those of the immediate transplantation group (1.73 +/- 0.8 pmol vs 1.89 +/- 0.5 pmol, respectively; P =.31). Peak airway pressure and myeloperoxidase activity were comparable among groups.. Donor and recipient treatment with trimetazidine provided a significant protection of the energy status, better oxygenation, and reduced lipid peroxidation in this experimental model. Our data suggest that trimetazidine may be an important adjunct to prolong ischemic time safely and to decrease lung ischemia-reperfusion injury.

Topics: Adenosine Triphosphate; Animals; Cold Temperature; Energy Metabolism; Lipid Peroxidation; Lung; Lung Transplantation; Male; Peroxidase; Rats; Rats, Inbred F344; Reperfusion Injury; Thiobarbituric Acid Reactive Substances; Trimetazidine; Vasodilator Agents

The effect of adrenomedullin, a vasodilatory peptide on transient middle cerebral artery (MCA) occlusion was investigated in rats.. Transient MCA occlusion for 2 hours was made by using the intra-arterial suture method, followed by reperfusion.. An intravenous infusion of adrenomedullin (1 microg/kg/min) from one hour before ischemia to one hour after ischemia significantly reduced the infarct size and improved neurological deficits (p<0.05), without affecting systemic blood pressure or other physiological parameters. The infarct size was reduced with adrenomedullin by 25.4+/-12.7%, 31.3+/-5.8%, 31.6+/-6.1% respectively at the coronal level 6, 8 and 10 mm posterior from the frontal pole. Adrenomedullin also significantly inhibited the increase in myeloperoxidase (MPO) activity in the MCA area of the ischemic hemisphere after 22-hour reperfusion (control: 0.205+/-0.054 unit/g wet tissue, adrenomedullin group: 0.047+/-0.009 unit/g wet tissue, p<0.0001).. These data suggest that adrenomedullin reduces acute ischemic brain injury and one of is neuroprotective mechanisms may be derived from inhibition of the infiltration of neutrophils into the ischemic tissue.

Topics: Adrenomedullin; Animals; Brain Ischemia; Disease Models, Animal; Infarction, Middle Cerebral Artery; Ischemic Attack, Transient; Male; Neutrophils; Peptides; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Vasodilator Agents

The aim of the present study was to investigate the protective effect of the pineal secretary product melatonin in a model of splanchnic artery occlusion shock (SAO). SAO shock was induced in rats by clamping both the superior mesenteric artery and the celiac trunk for 45 min, followed thereafter by release of the clamp (reperfusion). At 60 min after reperfusion, animals were sacrificed for tissue histological examination and biochemical studies. There was a marked increase in the oxidation of dihydrorhodamine 123 to rhodamine (a marker of peroxynitrite-induced oxidative processes) in the plasma of the SAO-shocked rats after reperfusion, but not during ischemia alone. Immunohistochemical examination demonstrated a marked increase in the immunoreactivity to nitrotyrosine, an index of nitrogen species such as peroxynitrite, in the necrotic ileum in shocked rats. SAO-shocked rats developed a significant increase of tissue myeloperoxidase and malondialdehyde activity, and marked histological injury to the distal ileum. SAO shock was also associated with a significant mortality (0% survival at 2 hr after reperfusion). Reperfused ileum tissue sections from SAO-shocked rats showed positive staining for P-selectin, which was mainly localized in the vascular endothelial cells. Ileum tissue sections obtained from SAO-shocked rats with anti-intercellular adhesion molecule (ICAM-1) antibody showed a diffuse staining. Melatonin (applied at 3 mg/kg, 5 min prior to reperfusion, followed by an infusion of 3 mg/kg per hr), significantly reduced ischemia reperfusion injury in the bowel as evaluated by histological examination. This prevented the infiltration of neutrophils into the reperfused intestine, is evidenced by reduced myeloperoxidase activity and reduced lipid peroxidation. This was evaluated by malondialdehyde activity which reduced the production of peroxynitrite during reperfusion, markedly reduced the intensity and degree of P-selectin and ICAM-1 in tissue section from SAO-shocked rats and improved their survival. Taken together, our results clearly demonstrate that melatonin treatment exerts a protective effect and part of this effect may be due to inhibition of the expression of adhesion molecule and peroxynitrite-related pathways and subsequent reduction of neutrophil-mediated cellular injury.

Topics: Animals; Chemotaxis, Leukocyte; Endothelium, Vascular; Free Radical Scavengers; Ileal Diseases; Immunoenzyme Techniques; Intercellular Adhesion Molecule-1; Male; Malondialdehyde; Melatonin; Mesenteric Artery, Superior; Neutrophils; Oxidative Stress; P-Selectin; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Splanchnic Circulation; Tyrosine

To investigate the effects of intestinal ischemia and reperfusion (I/R) on the pulmonary vascular endothelium and smooth muscle.. Respiratory failure is an important cause of death and complications after intestinal I/R. Although the mechanism of respiratory failure in this setting is complex and poorly understood, recent studies of lung injury suggest that endothelial dysfunction may play a significant role.. A rat model of acute lung injury was studied after 60 minutes of superior mesenteric arterial occlusion followed by either 120 or 240 minutes of reperfusion. The pulmonary vasomotor function was examined in isolated lungs perfused at a constant flow rate.. Sixty minutes of intestinal ischemia followed by 120 or 240 minutes of reperfusion led to a significant reduction in the ability of the pulmonary vasculature to respond to angiotensin II, acetylcholine, and calcium ionophore but not to nitroglycerin. The vasoconstriction response to N(G)-nitro-L-arginine methyl ester, which is a measure of basal nitric oxide release, was diminished in the 240-minute reperfusion group. Intestinal I/R was also associated with pulmonary leukosequestration and increased pulmonary microvascular leakage.. Basal and agonist-stimulated release of nitric oxide from the pulmonary vascular endothelium and the ability of pulmonary smooth muscle to contract in response to angiotensin II were impaired by intestinal I/R. Such functional impairment in both pulmonary vascular endothelium and smooth muscle may contribute to the alveolocapillary dysfunction and pulmonary hypertension found in acute lung injury after intestinal I/R.

Topics: Animals; Capillary Permeability; Endothelium, Vascular; Intestines; Ischemia; Lung; Male; Microcirculation; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Respiratory Distress Syndrome; Vascular Resistance; Vasomotor System

Myeloperoxidase (MPO) immunohistochemistry was used to ascertain the role of polymorphonuclear leukocytes in hyperglycemia-induced accentuation of brain injury after transient ischemia. Rats received 12.5 min of normothermic global cerebral ischemia by bilateral carotid occlusion plus hypotension. Hyperglycemia was induced before ischemia by intraperitoneal dextrose administration. Quantitative MPO immunohistochemistry was performed at 24 h and 3 days postischemia. Brains of normoglycemic-ischemic animals contained almost no MPO activity. By contrast, striking numbers of MPO-positive cells were present in brains studied 24 h after hyperglycemic ischemia, both within pial and parenchymal vessels and within the parenchyma. MPO deposition tended to subside at 3 days. These results indicate that hyperglycemia triggers the early, massive deposition of neutrophils in the postischemic brain--an event that may contribute to exacerbation of injury.

Topics: Animals; Blood-Brain Barrier; Brain; Cell Adhesion; Endothelium, Vascular; Glucose; Hyperglycemia; Ischemic Attack, Transient; Male; Neutrophils; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury

Sulfatide binds to P- and L-selectin, which play important roles in the initiation of neutrophil-endothelial interactions. Sulfatide protects skin flaps from ischemia-reperfusion injury. The purpose of this study was to evaluate the augmented protection when anti-rat ICAM-1 and anti-rat LFA-1 antibodies are combined with sulfatide in the ischemia-reperfusion model of rat skin flaps. Sulfatide was administered intravenously just before elevation of the right abdominal epigastric flap, and monoclonal antibodies were injected 30 min before clamp release. The femoral artery and vein were clamped above and below the epigastric vessels for 11 h and then the clamp was released. The administration of both sulfatide and monoclonal antibodies significantly increased the flap surviving area (6.58 +/- 0.61 cm(2) versus the group with monoclonal antibodies alone, 4.43 +/- 0.32 cm(2), P = 0.01). In the untreated rats the area was 1.86 +/- 0.36 cm(2). Histological examination 24 h after reperfusion in the group treated with sulfatide and monoclonal antibodies showed only slight leukocyte invasion into the flap, and myeloperoxidase activity 24 h after reperfusion was significantly reduced. This study indicates that both sulfatide and monoclonal antibodies protect rat skin flaps from ischemia-reperfusion injury.

Topics: Animals; Antibodies, Monoclonal; Intercellular Adhesion Molecule-1; Lymphocyte Function-Associated Antigen-1; Male; Peroxidase; Rats; Rats, Inbred Lew; Reperfusion Injury; Sulfoglycosphingolipids; Surgical Flaps

Lower torso ischemia and reperfusion leads to remote organ leukosequestration and injury. We now examine the intermediary role of selectins and complement in mediating lung and liver injury after hindlimb ischemia.. Mice underwent a 2-hour bilateral tourniquet hind-limb ischemia followed by 3 hours of reperfusion.. Neutrophil depletion significantly decreased lung vascular permeability index (PI), measured by the extravasation of 125I-albumin, and liver injury as assessed by serum alanine aminotransferse levels. Lung PI and serum alanine aminotransferse levels were also reduced in mice treated with recombinant soluble P-selectin glycoprotein ligand-immunoglobulin fusion protein. Complement inhibition with soluble complement receptor type 1 decreased lung PI and serum alanine aminotransferse levels. C5-deficient mice exhibited a similar decrease in lung PI and liver injury. Lung and liver injury were restored in C5-deficient mice reconstituted with wild-type serum.. Remote organ injury after lower torso reperfusion is selectin and complement dependent.

Topics: Alanine Transaminase; Animals; Capillary Permeability; Complement C5; Complement System Proteins; Disease Models, Animal; Hindlimb; Ischemia; Liver Diseases; Lung Diseases; Male; Membrane Glycoproteins; Mice; Mice, Inbred C57BL; Mice, Inbred Strains; Multiple Organ Failure; Neutrophils; Peroxidase; Receptors, Complement; Reperfusion Injury; Selectins

Nitric oxide regulates vascular tone, inhibits platelet aggregation, and inhibits leukocyte adhesion, all of which are important modulators of ischemia-reperfusion injury. This study aimed to determine the effects of endothelial constitutive nitric oxide synthase gene transfer on ischemia-reperfusion injury in a rat lung transplant model.. In group I, donor animals were injected intravenously with 5 x 10(9) pfu of adenovirus-encoding endothelial constitutive nitric oxide synthase. Groups II and III served as controls, whereby donor animals were injected with either 5 x 10(9) pfu of adenovirus encoding beta-galactosidase or saline solution, respectively. Twenty-four hours after injection, left lungs were harvested and preserved for 18 hours at 4 degrees C, then implanted into isogeneic recipients, which were put to death 24 hours later. Recombinant endothelial constitutive nitric oxide synthase gene expression was evaluated by Western blotting and immunohistochemistry. Lung grafts were assessed by measuring arterial oxygenation, myeloperoxidase activity, and wet/dry weight ratios.. Western blotting confirmed the overexpression of endothelial constitutive nitric oxide synthase in lungs so transfected compared with controls. Twenty-four hours after reperfusion, mean arterial oxygenation was significantly improved in group I compared with group II and III controls (189.4 +/- 47.1 mm Hg vs 71.7 +/- 8.9 mm Hg and 67.8 +/- 12.2 mm Hg, P =.02, P =.01, respectively). Myeloperoxidase activity, a reflection of tissue neutrophil sequestration, was also significantly reduced in group I compared with groups II and III (0.136 +/- 0.038 DeltaOD/mg/min vs 0. 587 +/- 0.077 and 0.489 +/- 0.126 DeltaOD/mg/min, P =.001, P =.01, respectively).. Adenovirus-mediated gene transfer with endothelial constitutive nitric oxide synthase ameliorates ischemia-reperfusion injury as manifested by significantly improved oxygenation and decreased neutrophil sequestration in transplanted lung isografts. Endothelial constitutive nitric oxide synthase gene transfer may reduce acute lung dysfunction after lung transplantation.

Topics: Adenoviridae; Animals; Blotting, Western; Disease Models, Animal; Gene Expression; Gene Transfer Techniques; Genetic Vectors; Lung; Lung Transplantation; Nitric Oxide Synthase; Nitric Oxide Synthase Type III; Oxygen Consumption; Peroxidase; Rats; Rats, Inbred F344; Reperfusion Injury; Transplantation, Homologous

Controlled reperfusion with a modified solution limits pulmonary injury following ischemia. Our initial studies infused this modified reperfusate at a pressure of 40 to 50 mm Hg to insure distribution. However, perhaps a lower pressure, which is closer to the normal physiologic pressure in the lung, would improve results by decreasing sheer stress.. Fifteen adult pigs underwent 2 hours of lung ischemia by clamping the left bronchus and pulmonary artery. Five (group 1) then underwent uncontrolled reperfusion by removing the vascular clamps and allowing unmodified blood to reperfuse the lung at a pulmonary artery pressure of 20 to 30 mm Hg. The other 10 pigs underwent controlled reperfusion by mixing blood from the femoral artery with a crystalloid solution, and infusing this modified reperfusate into the ischemic lung through the pulmonary artery for 10 minutes before removing the arterial clamp. In 5 (group 2), the modified solution was infused at a pressure of 40 to 50 mm Hg, and in 5 (group 3) 20 to 30 mm Hg. Lung function was assessed 60 minutes after reperfusion and expressed as percentage of control.. Compared to uncontrolled reperfusion (group 1), controlled reperfusion at a pressure of 40 to 50 mm Hg (group 2) significantly improved postreperfusion pulmonary compliance (77% versus 86%; p<0.001 versus group 1), and arterial/alveolar ratio (a/A) ratio (27% versus 52%; p<0.001 versus group 1); as well as decreased pulmonary vascular resistance (PVR) (198% versus 154%; p<0.001 versus group 1), lung water (84.3% versus 83.5%; p<0.001 versus group 1), and myeloperoxidase (0.35 versus 0.23 optical density/min/mg protein). Reducing the pressure of the modified reperfusate to 20 to 30 mm Hg further improved postreperfusion compliance (92%+/-1%; p<0.001 versus groups 1 and 2) and a/A ratio (76%+/-1%; p<0.001 versus groups 1 and 2); and lowered PVR (133%+/-2%; p<0.001 versus groups 1 and 2), lung water (82.7%+/-0.1%; p<0.001 versus groups 1 and 2), and myeloperoxidase (0.16%+/-0.01%; p<0.001 versus groups 1 and 2).. After 2 hours of pulmonary ischemia, a severe lung injury occurs following uncontrolled reperfusion, controlled reperfusion with a modified solution reduces this reperfusion injury, and lowering the pressure of the modified reperfusate to more physiologic levels (20 to 30 mm Hg) further reduces the reperfusion injury improving pulmonary function.

Topics: Animals; Blood; Blood Pressure; Body Water; Bronchi; Constriction; Ischemia; Lung; Lung Compliance; Organ Preservation Solutions; Peroxidase; Pressure; Pulmonary Artery; Pulmonary Edema; Pulmonary Gas Exchange; Reperfusion; Reperfusion Injury; Rheology; Swine; Vascular Resistance

The literature contains investigations and discussion of the role of neutrophils and neutrophil-derived myeloperoxidase (MPO) in inflammatory processes, local ischaemia, and ischaemia-reperfusion injury models. Our aim was to determine whether the same roles existed for neutrophils and the system involving neutrophil-derived MPO in experimental subarachnoid haemorrhage (SAH) and associated ischaemia.. Forty-eight adult New Zealand white rabbits were divided into six groups of eight. The first SAH model was applied to 16 animals. Eight of these rabbits were sacrificed after 48 hours (Group 1) and the remaining eight were killed after 96 hours (Group 2). The second SAH model applied to another 16 rabbits, which were sacrificed in two groups at the above time periods, forming Groups 3 and 4, respectively. There were two groups of 8 control animals, one group per SAH model, and these rabbits were sacrificed after 48 hours. We carried out histopathological studies using haematoxylin and eosin (H&E) stain, elastin stain, MPO immunohistochemistry, and determination of basilar artery cross-sectional diameter. We also did biochemical analysis of cerebral hemisphere and brainstem specimens, measuring tissue lipid peroxidase and MPO activity. Results were compared between the groups and with their related controls.. In contrast to previous experimental findings in local ischaemia and ischaemia-reperfusion models, we found no histopathological or biochemical evidence to suggest a role for neutrophils and neutrophil-derived MPO in relation to subarachnoid haemorrhage and resultant vasospasm. Although we confirmed the successful induction of significant vasospasm and observed the clinical evidences of subsequent ischaemia, there was no notable accumulation of neutrophils or activity of neutrophil-derived MPO in the tissues studied. This suggests that the biological process induced by SAH follows a different pattern from that seen in local ischaemia and ischaemia-reperfusion injury.

Topics: Animals; Brain Ischemia; Disease Models, Animal; Neutrophils; Peroxidase; Rabbits; Reperfusion Injury; Subarachnoid Hemorrhage; Vasospasm, Intracranial

The relative contribution of xanthine oxidase (XO) and leukocytes to tissue injury after short-term ischemia is unknown. In this study, we subjected three groups of rat spinotrapezius muscles to 30-min ischemia and 1-h reperfusion: 1) ischemia-reperfusion (I/R) + 0.9% saline, 2) I/R + superoxide dismutase, and 3) I/R + oxypurinol. A fourth group served as nonischemic control. We quantified the increase in resistance (%DeltaR) caused by leukocyte-capillary plugging concurrently with myocyte uptake of propidium iodide (PI) [expressed as no. of PI spots per total volume of perfused tissue (N(PI)/V)] and performed assays to quantify XO activity, thiobarbituric acid-reactive substances (TBARS), and myeloperoxidase (MPO). Groups 2 and 3 exhibited significant decreases in N(PI)/V relative to group 1. MPO levels and TBARS were similar among all groups, and mean %DeltaR was significantly reduced in groups 2 and 3 relative to group 1. However, elevated XO was observed in groups 1 and 2 relative to group 3 and nonischemic controls. These data are consistent with the hypothesis that XO, rather than toxic species produced by plugging or venule-adherent leukocytes, is responsible for postischemic damage in this model.

Topics: Animals; Capillaries; Cell Adhesion; Cell Movement; Female; Ischemia; Leukocytes; Lipid Peroxides; Muscle, Skeletal; Oxidants; Oxypurinol; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Sodium Chloride; Superoxide Dismutase; Time Factors; Vascular Resistance; Xanthine Oxidase

Inflammatory responses and oxygen free radicals have increasingly been implicated in the development of ischemic brain injury. In some cases, an attenuation of inflammation or free-radical injury can provide tissue protection. Diphosphoryl lipid A (DPL) is a detoxified derivative of a lipopolysaccharide (endotoxin) of Salmonella minnesota strain R595, which is capable of stimulating the immune system without eliciting direct toxic effects. In this study the authors examined the influence of preconditioning with DPL on ischemia/reperfusion injury in rats.. Sprague-Dawley rats were injected intravenously with either DPL or vehicle. Twenty-four hours later, some animals were tested for superoxide dismutase (SOD) activity. Others were subjected to a 3-hour period of focal cerebral ischemia and, after a reperfusion period of 24 hours, were killed. Infarction volume, SOD activity, and myeloperoxidase (MPO) activity were assayed in the postischemic animals. Pretreatment with DPL produced significant reductions in cerebral infarction and MPO activity in the ischemic penumbra. A significant enhancement of basal SOD activity was observed 24 hours after DPL treatment (that is, before ischemia), and a further enhancement of SOD activity was seen in the ischemic penumbra 24 hours after reperfusion.. These data provide the first evidence of a neuroprotective effect of preconditioning with DPL in an in vivo model of cerebral ischemia. Although the precise mechanisms through which DPL exerts its neuroprotective influence remain to be established, an inhibition of the complex inflammatory response to ischemia and an enhancement of endogenous antioxidant activity are leading candidates.

Topics: Animals; Brain; Cerebral Infarction; Ischemic Attack, Transient; Ischemic Preconditioning; Lipid A; Male; Peroxidase; Premedication; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Reperfusion Injury; Superoxide Dismutase

to investigate endogenous pulmonary nitric oxide metabolism following infrarenal aortic cross-clamp-induced ischaemia-reperfusion injury.. groups of male Wistar rats (n=6) were subjected to 60 minutes of infrarenal aortic cross-clamping under general anaesthesia. Rats were culled after 0, 60 and 120 minutes>> reperfusion, following release of the aortic clamp. A sham-operated control group was also studied. Acute lung injury (ALI) was quantified by measuring the protein concentration in lung bronchoalveolar lavage (BAL) fluid. Pulmonary myeloperoxidase activity (MPO) was measured as an index of neutrophil infiltration and degranulation in the lung. Plasma tumour-necrosis factor-alpha (TNF-alpha) was measured as an index of the pro-inflammatory cytokine response and pulmonary nitric oxide synthase (NOS) activity was determined by measuring conversion of(3)H L-arginine to(3)H L-citrulline in tissue homogenates.. these data show significant ALI with increased pulmonary microvascular permeability and MPO activity in animals subject to 60 minutes>> ischaemia and 60 minutes or 120 minutes of reperfusion compared to control animals (p<0.01). Plasma TNF-alpha levels were significantly increased following 60 minutes of ischaemia compared to controls (p<0.01) and remained significantly increased in animals subject to reperfusion (p<0.01). Pulmonary NOS activity was significantly increased in animals subject to reperfusion (p<0.01).. the reperfusion phase of infrarenal aortic cross-clamping provokes a significant increase in pulmonary NOS metabolism. The increase in plasma TNF-alpha and MPO activity suggests that this response may be secondary to inducible NOS expression. Manipulation of this response may benefit patients at risk of acute injury following infrarenal aortic reconstruction.

Topics: Animals; Aorta, Abdominal; Bronchoalveolar Lavage Fluid; Capillary Permeability; Constriction; Lung; Male; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Time Factors; Tumor Necrosis Factor-alpha

Prevention of ischemia-reperfusion (IR) injury is crucial for successful lung transplantation. We investigated whether a nitric oxide donor, nitroglycerin (NTG), could suppress the oxidative stress of IR injury and improve pulmonary function after reperfusion in an ex vivo rat lung perfusion model. In Fresh group of animals, the lungs were flushed with perfusate, followed immediately by reperfusion, and no lung injury was observed. In NTG- and NTG+ groups of animals, the lungs were flushed with perfusate alone or perfusate containing NTG, respectively. Harvested lung and heart blocks from these latter two groups were immersed in the corresponding perfusate at 4 degrees C for 15 h, and were then reperfused for 60 min. Reperfusion induced pulmonary edema in the NTG- group, but not in the NTG+ group. Shunt fractions in NTG+ group were significantly lower than in the NTG- group throughout reperfusion. NTG had no effect on pulmonary arterial pressure or myeloperoxidase activity. In contrast, oxidative DNA damage assessed immunohistochemically with a monoclonal antibody against 8-hydroxy-2'-deoxyguanosine (8-OHdG) was significantly increased in the NTG- group, in the order alveolar epithelium > pulmonary endothelium > bronchial epithelium. NTG treatment significantly decreased staining with the anti-8-OHdG antibody in all three areas of tissue. Therefore, administration of NTG attenuates the oxidative stress of IR injury, and may improve pulmonary function after reperfusion.

Topics: Animals; Cyclic GMP; DNA Damage; Immunoenzyme Techniques; Lung; Lung Transplantation; Male; Nitroglycerin; Organ Preservation; Oxidative Stress; Peroxidase; Pulmonary Alveoli; Pulmonary Edema; Rats; Rats, Inbred Lew; Reperfusion Injury; Vasodilator Agents

We assessed a kallikrein-like amidase activity probably related to the kallikrein-kinin system, as well as the participation of leukocyte infiltration in renal ischemia and reperfusion. Male C57BL/KSJmdb mice were subjected to 20 or 60 min of ischemia and to different periods of reperfusion. A control group consisted of sham-operated mice, under similar conditions, except for ischemia induction. Kallikrein-like amidase activity, Evans blue extravasation and myeloperoxidase activity were measured in kidney homogenates, previously perfused with 0.9% NaCl. Plasma creatinine concentration increased only in the 60-min ischemic group. After 20 min of ischemia and 1 or 24 h of reperfusion, no change in kallikrein-like amidase activity or Evans blue extravasation was observed. In the mice subjected to 20 min of ischemia, edema was evident at 1 h of reperfusion, but kidney water content returned to basal levels after 24 h of reperfusion. In the 60-min ischemic group, kallikrein-like amidase activity and Evans blue extravasation showed a similar significant increase along reperfusion time. Kallikrein-like amidase activity increased from 4 nmol PNA mg protein-1 min-1 in the basal condition to 15 nmol PNA mg protein-1 min-1 at 10 h of reperfusion. For dye extravasation the concentration measured was near 200 microg of Evans blue/g dry tissue in the basal condition and 1750 microg of Evans blue/g dry tissue at 10 h of reperfusion. No variation could be detected in the control group. A significant increase from 5 to 40 units of DeltaAbs 655 nm g wet tissue-1 min-1 in the activity of the enzyme myeloperoxidase was observed in the 60-min ischemic group, when it was evaluated after 24 h of reperfusion. Histological analysis of the kidneys showed migration of polymorphonuclear leukocytes from the vascular bed to the interstitial tissue in the 60-min ischemic group after 24 h of reperfusion. We conclude that the duration of ischemia is critical for the development of damage during reperfusion and that the increase in renal cortex kallikrein-like amidase activity probably released from both the kidney and leukocytes may be responsible, at least in part, for the observed effects, probably through direct induction of increased vascular permeability.

Topics: Amidohydrolases; Animals; Capillary Permeability; Creatinine; Ischemia; Kallikreins; Kidney; Male; Mice; Mice, Inbred C57BL; Microcirculation; Peroxidase; Reperfusion Injury

Submucosal injection of endothelin (ET)-1 induces gastric ulcer. We investigated the roles of neutrophils and adhesion molecules (intercellular adhesion molecule (ICAM)-1 and CD18) in the development of ET-1-induced ulcers in rats. Ulcers were induced by submucosal injection of ET-1. Rats were injected with anti-neutrophil serum or F(ab')2 fragments of irrelevant mouse IgG2a (control), anti-ICAM-1 antibody, or anti-CD18 antibody. Ulcer tissues were subjected to measurement of myeloperoxidase (MPO) activity, ulcer size, and immunohistochemical study. Within 3 hr, arterial vasoconstriction and vascular congestion were observed at sites of ET-1 injection. By 6 hr, vascular congestion had disappeared, and ICAM-1 expression had markedly increased in venules in deep portions of the mucosa and submucosa, accompanied by an increase in the number of CD18-positive neutrophils. By 48 hr, ulcers that extended into the submucosa had developed. In controls, MPO activity gradually increased and was maximal by 6 hr. Neutrophil depletion, and immunoneutralizing of ICAM-1 and CD18 inhibited the increase in MPO activity, and decreased ulcer sizes measured at 48 hr. In conclusion, ET-1 causes ischemia-reperfusion injury, and neutrophil accumulation after reperfusion mediated by the ICAM-1-CD18 pathway may be important in the development of ET-1-induced gastric ulcer.

Topics: Animals; CD18 Antigens; Endothelin-1; Gastric Mucosa; Injections; Intercellular Adhesion Molecule-1; Male; Mice; Neutrophils; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Stomach Ulcer

Ischemia/reperfusion (I/R) injury appears to be a significant neutrophil-dependent component and may be ameliorated by blocking leukocyte-endothelial adhesion. Using a rat extensor digitorum longus (EDL) muscle model, the present study tested the hypothesis that in vivo administration of the function-blocking monoclonal antibody (mAb) LAM1-116 which recognizes L-selectin, a cell-surface adhesion receptor, could decrease I/R injury. In 46 rats, one EDL served as a normal control and the opposite EDL underwent 3 hr of ischemia followed by 3 hr of reperfusion after pretreatment with LAM1-116 mAb, control IgG, or saline. Myeloperoxidase (MPO) activity showed only a two-fold increase from normal in LAM1-116-treated I/R EDL while a 27-fold increase occurred in the IgG2a and saline groups, with a statistically significant (p < 0.001) difference. A significantly (p < 0.05) lower wet weight ratio, improved fatigue contractile force, and less neutrophil infiltration were found in LAM1-116-treated EDL, when compared to those in control IgG- or saline-treated EDL. The results indicate that blockade of L-selectin by LAM1-116 mAb can effectively reduce neutrophil infiltration in reperfused skeletal muscle, thereby decreasing tissue edema and improving muscle fatigue contractile force. These findings may be important in understanding I/R injury.

Topics: Animals; Antibodies, Monoclonal; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Immunoglobulin G; L-Selectin; Leukocyte Count; Muscle Contraction; Muscle, Skeletal; Organ Size; Peroxidase; Rats; Rats, Sprague-Dawley; Reference Values; Reperfusion Injury; Sensitivity and Specificity

Previous work has indicated that complement is a mediator of ischemia/reperfusion (I/R) injury. To investigate the components of complement responsible for this effect, we examined a model of renal I/R injury in C3-, C4-, C5-, and C6-deficient mice. We occluded the renal arteries and veins (40-58 minutes) and, after reperfusion (0-72 hours), assessed renal structural and functional injury. C3-, C5-, and C6-deficient mice were protected from renal I/R injury, whereas C4-deficient mice were not protected. C6-deficient mice treated with antibody to block C5a generation showed no additional protection from I/R injury. Reconstitution with C6 alone restored the I/R injury in C6-deficient mice. Tubular epithelial cells were the main structures damaged by complement-mediated attack, and, in contrast, the renal vessels were spared. Neutrophil infiltration and myeloperoxidase activity were reduced in C-deficient mouse kidney, but by a similar extent in C3-deficient and C6-deficient mice. We conclude that the membrane attack complex of complement (in which C5 and C6 participate) may account for the effect of complement on mouse renal I/R injury. Neither C5a-mediated neutrophil infiltration nor the classic pathway, in which C4 participates, appears to contribute to I/R injury in this model. By contrast with other organs, such as the heart, the primary effect of complement in the ischemic area is on the parenchymal cell rather than the vascular endothelial cell. The membrane attack complex of complement is a potential target for prevention of I/R injury in this model.

Topics: Animals; Complement Activation; Complement C3; Complement C4; Complement C5; Complement C6; Complement Membrane Attack Complex; Disease Models, Animal; Kidney; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophils; Peroxidase; Reperfusion Injury

Cell death following ischemia-reperfusion injury is a major concern in clinical issues such as organ transplantation and trauma. The need to identify agents with a potential for preventing such damage has assumed great importance. We have evaluated the efficacy of picroliv, a potent antioxidant derived from the plant Picrorhiza kurrooa, in protecting against hepatic ischemia-reperfusion injury in vivo. Picroliv was fed to male Sprague Dawley rats in a dose of 12 mg/kg once daily by oral gavage for 7 days prior to hepatic ischemia. Ischemia was induced by occluding the hepatic pedicel with a microaneurysm clip for 30 min and reperfusion was allowed thereafter for varying period (15-120 min) by releasing the microaneurysm clip. Picroliv pretreatment resulted in better hepatocyte glycogen preservation and reduced apoptosis. Reduction in apoptosis was associated with decreased mRNA expression of caspase-3 and Fas. Oxidant induced cellular damage as measured by tissue malondialdehyde (MDA) levels was significantly less following picroliv pretreatment. Both a reduction in neutrophil infiltration and an increased level of intracellular antioxidant enzyme superoxide dismutase possibly contributed to the reduction in tissue lipid peroxidation. Tissue inflammatory cytokines level of interleukin-1alpha (IL-1alpha) and interleukin-1beta (IL-1beta) was also lower in picroliv group. Furthermore, picroliv pretreatment resulted in enhanced proliferating cell nuclear antigen (PCNA) immunoreactivity. These studies strongly suggest picroliv to be a promising agent for ameliorating injury following ischemia-reperfusion.

Topics: Animals; Apoptosis; Caspase 1; Caspase 2; Caspases; Cinnamates; Gene Expression Regulation; Glycosides; Immunohistochemistry; Interleukin-1; Lipid Peroxidation; Liver; Liver Glycogen; Liver Regeneration; Male; Microscopy, Electron, Scanning; Peroxidase; Plant Extracts; Proliferating Cell Nuclear Antigen; Proto-Oncogene Proteins c-bcl-2; Rats; Rats, Sprague-Dawley; Reperfusion Injury; RNA, Messenger; Superoxide Dismutase; Vanillic Acid

The aim of the present study was to investigate the protective effect of the peroxynitrite decomposition catalyst 5,10,15, 20-tetrakis(2,4,6-trimethyl-3,5-disulfonatophenyl)-porphyrinato iron (III) (FeTMPS) in a model of splanchnic artery occlusion shock (SAO). SAO shock was induced in rats by clamping both the superior mesenteric artery and the celiac trunk for 45 min, followed by release of the clamp (reperfusion). At 60 min after reperfusion, animals were killed for histological examination and biochemical studies. There was a marked increase in the oxidation of dihydrorhodamine 123 to rhodamine (a marker of peroxynitrite-induced oxidative processes) in the plasma of the SAO-shocked rats after reperfusion, but not during ischemia alone. Immunohistochemical examination demonstrated a marked increase in the immunoreactivity to nitrotyrosine, an index of nitrogen species such as peroxynitrite, in the necrotic ileum in shocked rats. SAO-shocked rats developed a significant increase of tissue myeloperoxidase and malonaldehyde activity, and marked histological injury to the distal ileum. SAO shock was also associated with a significant mortality (0% survival at 2 h after reperfusion). Reperfused ileum tissue sections from SAO-shocked rats showed positive staining for P-selectin localized mainly in the vascular endothelial cells. Ileum tissue sections obtained from SAO-shocked rats and stained with antibody to ICAM-1 showed a diffuse staining. Administration of FeTMPS significantly reduced ischemia/reperfusion injury in the bowel, and reduced lipid and the production of peroxynitrite during reperfusion. Treatment with PN catalyst also markedly reduced the intensity and degree of P-selectin and ICAM-1 staining in tissue sections from SAO-shocked rats and improved survival. Our results clearly demonstrate that peroxynitrite decomposition catalysts exert a protective effect in SAO and that this effect may be due to inhibition of the expression of adhesion molecules and the tissue damage associated with peroxynitrite-related pathways.

Topics: Animals; Blood Pressure; Catalysis; Celiac Artery; Disease Models, Animal; Endothelium, Vascular; Ferric Compounds; Ileum; Intercellular Adhesion Molecule-1; Leukocyte Count; Lipid Peroxidation; Male; Malondialdehyde; Metalloporphyrins; Nitrates; Nitric Oxide; Nitrites; Oxidative Stress; P-Selectin; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Rhodamines; Splanchnic Circulation; Tyrosine

We examined whether activated protein C (APC) reduces ischemia/reperfusion (I/R)-induced renal injury by inhibiting leukocyte activation. In a rat model, intravenous administration of APC markedly reduced I/R-induced renal dysfunction and histological changes, whereas intravenous administration of dansyl glutamylglycylarginyl chloromethyl ketone-treated factor Xa (DEGR-FXa; active-site-blocked factor Xa), heparin or diisopropyl fluorophosphate-treated APC (DIP-APC; inactive derivative of ARC) had no effect. Furthermore, APC significantly inhibited the I/R-induced decrease in renal tissue blood flow and the increase in the vascular permeability, whereas neither DEGR-FXa, heparin, nor DIP-APC produced such effects. Renal I/R-induced increases in plasma levels of fibrin degradation products were significantly inhibited by APC, DEGR-FXa, and heparin. These observations suggest that APC reduces I/R-induced renal injury independently of its anticoagulant effects but in a manner dependent on its serine protease activity. Renal levels of tumor necrosis factor-alpha (TNF-alpha), rat interleukin-8, and myeloperoxidase were significantly increased after renal I/R. These increases were significantly inhibited by APC but not by DEGR-FXa, heparin, or DIP-APC. Leukocytopenia produced effects similar to those of APC. These findings strongly suggest that APC protects against I/R-induced renal injury not by inhibiting coagulation abnormalities but by inhibiting activation of leukocytes that play an important role in I/R-induced renal injury. Inhibition of leukocyte activation by APC could be explained by the inhibitory activity of TNF-alpha. (Blood. 2000;95:3781-3787)

Topics: Amino Acid Chloromethyl Ketones; Animals; Antithrombins; Cytokines; Factor Xa; Heparin; Humans; Interleukin-8; Isoflurophate; Kidney; Male; Peroxidase; Protein C; Rats; Rats, Wistar; Regional Blood Flow; Reperfusion Injury; Tumor Necrosis Factor-alpha

Complex limb trauma often involves combined arterial and venous injury, and the resultant ischaemia-reperfusion injury (IRI) causes both local and remote organ injury. This study assessed the influence of the timing of restoration of venous drainage on IRI.. Male New Zealand white rabbits (n = 36) were randomized into six groups: sham operation (group 1) and unilateral hind limb arterial and venous occlusion for 1 h followed by no reflow for 2 h (group 2), arterial and venous reflow for 2 h (group 3), arterial reflow alone for 2 h (group 4), arterial reflow alone for 1 h followed by arterial and venous (delayed) reflow for a further 1 h (group 5), and pretreatment with an enteral combination antioxidant before occlusion of both artery and vein and delayed venous reflow (group 6). Plasma hydroperoxide (HPO) and glutathione peroxidase concentration, hind limb skeletal muscle and lung tissue wet : dry weight ratios and myeloperoxidase (MPO) concentration were measured.. The plasma HPO level in the femoral vein effluent was significantly greater after delayed venous reflow (mean(s.e.m.) 2. 02(0.54) micromol/l) than in control animals (0.98(0.10) micromol/l) (P < 0.05). There was also a significantly greater tissue wet : dry weight ratio after delayed venous reflow than in controls, in skeletal muscle (mean(s.e.m.) 6.89(0.14) versus 5.34(0.54); P < 0. 05) and lung (9.20(1.14) versus 7.23(0.38); P < 0.05) tissue. Lung tissue MPO activity was significantly greater after delayed venous reflow compared with controls (3.20(0.28) versus 1.86(0.14) units/g; P < 0.005), and also in comparison to simultaneous arterial and venous reflow (2.40(0.24) units/g; P < 0.05). In the antioxidant pretreatment group there was no significant increase in plasma HPO concentration, tissue MPO level or tissue wet : dry weight ratio compared with the control group.. In combined major arterial and venous injury of the limb, delayed restoration of venous drainage leads to significantly greater local skeletal muscle injury and remote neutrophil-mediated lung injury. These results support the clinical rationale for early restoration not only of arterial inflow but also venous drainage by means of intraluminal shunts.

Topics: Animals; Constriction; Extremities; Femoral Artery; Femoral Vein; Glutathione Peroxidase; Hydrogen Peroxide; Leukocyte Count; Male; Neutrophils; Peroxidase; Rabbits; Reperfusion Injury; Time Factors

1. Nitric oxide (NO), peroxynitrite, formed from NO and superoxide anion, poly (ADP-ribole) synthetase have been implicated as mediators of neuronal damage following focal ischaemia. Here we have investigated the effects of n-acetylcysteine (NAC) treatment in Mongolian gerbils subjected to cerebral ischaemia. 2. Treatment of gerbils with NAC (20 mg kg(-1) 30 min before reperfusion and 1, 2 and 6 h after reperfusion) reduced the formation of post-ischaemic brain oedema, evaluated by water content. 3. NAC also attenuated the increase in the brain levels of malondialdehyde (MDA) and the increase in the hippocampus of myeloperoxidase (MPO) caused by cerebral ischaemia. 4. Positive staining for nitrotyrosine was found in the hippocampus in Mongolian gerbils subjected to cerebral ischaemia. Hippocampus tissue sections from Mongolian gerbils subjected to cerebral ischaemia also showed positive staining for poly (ADP-ribose) synthetase (PARS). The degree of staining for nitrotyrosine and for PARS were markedly reduced in tissue sections obtained from animals that received NAC. 5. NAC treatment increased survival and reduced hyperactivity linked to neurodegeneration induced by cerebral ischaemia and reperfusion. 6. Histological observations of the pyramidal layer of CA1 showed a reduction of neuronal loss in animals that received NAC. 7. These results show that NAC improves brain injury induced by transient cerebral ischaemia.

Topics: Acetylcysteine; Animals; Brain; Brain Edema; Brain Ischemia; Free Radical Scavengers; Gerbillinae; Male; Malondialdehyde; Motor Activity; Nitric Oxide; Peroxidase; Poly(ADP-ribose) Polymerases; Reperfusion Injury; Time Factors; Tyrosine

The generation of reactive oxygen species (ROS) contributes to the pathogenesis of renal ischemia-reperfusion injury. The aim of this study was to investigate the effects of tempol in (1) an in vivo rat model of renal ischemia/reperfusion injury and on (2) cellular injury and death of rat renal proximal tubular (PT) cells exposed to oxidant stress in the form of hydrogen peroxide (H2O2).. Male Wistar rats underwent bilateral renal pedicle clamping for 45 minutes followed by reperfusion for six hours. Tempol (30 mg/kg/h), desferrioxamine (DEF; 40 mg/kg/h), or a combination of tempol (30 mg/kg/h) and DEF (40 mg/kg/h) were administered prior to and throughout reperfusion. Plasma concentrations of urea, creatinine, Na+, gamma-glutamyl transferase (gammaGT), aspartate aminotransferase (AST), and urinary Na+ and N-acetyl-beta-D-glucosaminidase (NAG) were measured for the assessment of renal function and reperfusion injury. Kidney myeloperoxidase (MPO) activity and malondialdehyde (MDA) levels were measured for assessment of polymorphonuclear (PMN) cell infiltration and lipid peroxidation, respectively. Renal sections were used for histologic grading of renal injury and for immunohistochemical localization of nitrotyrosine and poly(ADP-ribose) synthetase (PARS). Primary cultures of rat PT cells were incubated with H2O2 (1 mmol/L for 4 h) either in the absence or presence of increasing concentrations of tempol (0.03 to 10 mmol/L), DEF (0.03 to 10 mmol/L), or a combination of tempol (3 mmol/L) or DEF (3 mmol/L). PT cell injury and death were determined by evaluating mitochondrial respiration and lactate dehydrogenase (LDH) release, respectively.. In vivo, tempol significantly reduced the increase in urea, creatinine, gammaGT, AST, NAG, and FENa produced by renal ischemia/reperfusion, suggesting an improvement in both renal function and injury. Tempol also significantly reduced kidney MPO activity and MDA levels, indicating a reduction in PMN infiltration and lipid peroxidation, respectively. Tempol reduced the histologic evidence of renal damage associated with ischemia/reperfusion and caused a substantial reduction in the staining for nitrotyrosine and PARS, suggesting reduced nitrosative and oxidative stress. In vitro, tempol significantly attenuated H2O2-mediated decrease in mitochondrial respiration and increase in LDH release from rat PT cells, indicating a reduction in cell injury and death. Both in vivo and in vitro, the beneficial actions of tempol were similar to those obtained using the Fe2+ chelator DEF. However, coadministration of DEF and tempol did not produce any additional beneficial actions against renal ischemia/reperfusion injury or against oxidative stress-mediated PT cell injury/death.. Our results suggest that the membrane-permeable radical scavenger, tempol, reduces the renal dysfunction and injury associated with ischemia/reperfusion of the kidney.

Topics: Acute Kidney Injury; Animals; Cell Membrane Permeability; Cell Separation; Cells, Cultured; Chelating Agents; Cyclic N-Oxides; Deferoxamine; Disease Models, Animal; Free Radical Scavengers; Hydrogen Peroxide; Kidney Glomerulus; Kidney Tubules, Proximal; Male; Malondialdehyde; Necrosis; Oxidants; Oxidative Stress; Peroxidase; Poly(ADP-ribose) Polymerases; Rats; Rats, Wistar; Reperfusion Injury; Spin Labels; Tyrosine

Protein kinase C (PKC) inhibitors, chelerythrine (Chel, 0.6 mg) and polymyxin B (Poly B, 1.0 mg), and PKC activators, phorbol 12-myristate 13-acetate (PMA, 0.05 mg) and 1-oleoyl-2-acetyl glycerol (OAG, 0.1 mg), were used as probes to investigate the role of PKC in mediation of ischemic preconditioning (IPC) of noncontracting pig latissimus dorsi (LD) muscles against infarction in vivo. These drugs were delivered to each LD muscle flap (8 x 12 cm) by 10 min of local intra-arterial infusion. It was observed that LD muscle flaps sustained 43 +/- 5% infarction when subjected to 4 h of global ischemia and 24 h of reperfusion. IPC with three cycles of 10 min ischemia-reperfusion reduced muscle infarction to 25 +/- 3% (P < 0.05). This anti-infarction effect of IPC was blocked by Chel (42 +/- 7%) and Poly B (37 +/- 2%) and mimicked by PMA (19 +/- 10%) and OAG (14 +/- 5%) treatments (P < 0.05), given 10 min before 4 h of ischemia. In addition, the ATP-sensitive K(+) (K(ATP)) channel antagonist sodium 5-hydroxydecanoate attenuated (P < 0.05) the anti-infarction effect of IPC (37 +/- 2%), PMA (44 +/- 17%), and OAG (46 +/- 9%). IPC, OAG, and Chel treatment alone did not affect mean arterial blood pressure or muscle blood flow assessed by 15-microm radioactive microspheres. Western blot analysis of muscle biopsies obtained before (baseline) and after IPC demonstrated seven cytosol-associated isoforms, with nPKCepsilon alone demonstrating progressive cytosol-to-membrane translocation within 10 min after the final ischemia period of IPC. Using differential fractionation, it was observed that nPKCepsilon translocated to a membrane compartment other than the sarcolemma and/or sarcoplasmic reticulum. Furthermore, IPC and preischemic OAG but not postischemic OAG treatment reduced (P < 0.05) muscle myeloperoxidase activity compared with time-matched ischemic controls during 16 h of reperfusion after 4 h of ischemia. Taken together, these observations indicate that PKC plays a central role in the anti-infarction effect of IPC in pig LD muscles, most likely through a PKC-K(ATP) channel-linked signal-transduction pathway.

Topics: Adenosine; Alkaloids; Animals; Benzophenanthridines; Biological Transport; Decanoic Acids; Diglycerides; Enzyme Inhibitors; Hydroxy Acids; Infarction; Ischemic Preconditioning; Muscle, Skeletal; Neutrophils; Peroxidase; Phenanthridines; Potassium Channel Blockers; Protein Kinase C; Regional Blood Flow; Reperfusion Injury; Swine

To examine whether adenosine reduces ischemia/reperfusion (I/R)-induced liver injury by inhibiting leukocyte activation via A(2) receptor (A(2)R) stimulation, we investigated the effects of adenosine and selective A(2A) receptor (A(2A)R) agonists (YT-146 and CGS21680C) on I/R-induced liver injury in rats. Adenosine, YT-146, and CGS21680C, in the concentration of 10(-7) to 10(-5) M, significantly inhibited neutrophil elastase release by about 30 to 40% and increased intracellular Ca(2+) concentrations in isolated neutrophils stimulated with formyl-methionyl-leucyl-phenylalanine (fMLP) in vitro. Adenosine, YT-146, and CGS21680C, in the concentration of 10(-7) to 10(-5) M, significantly inhibited tumor necrosis factor (TNF)-alpha production by monocytes stimulated with endotoxin by about 50%. Although ZM241385, a selective A(2A)R antagonist, significantly enhanced the increase in neutrophil elastase release and intracellular Ca(2+) concentrations in neutrophils stimulated with fMLP, this agent did not affect the endotoxin-induced TNF-alpha production by monocytes. Rats were subjected to liver ischemia for 60 min. Serum levels of transaminases increased after hepatic I/R, peaking at 12 h after reperfusion. The i.v. infusion of adenosine (1 and 10 mg/kg/h), YT-146 (0.1 and 1 mg/kg/h), and CGS21680C (0.1 and 1 mg/kg/h) significantly inhibited the I/R-induced increase in serum transaminase levels 12 h after reperfusion. The I/R-induced decrease in hepatic tissue blood flow was significantly prevented by adenosine and YT-146. Hepatic levels of TNF-alpha, cytokine-induced neutrophil chemoattractant (equivalent to human interleukin-8), and myeloperoxidase were significantly increased after I/R. These increases were significantly inhibited by the administration of adenosine, YT-146, and CGS21680C. Although the histological neutrophil accumulation in the liver was significantly increased after I/R as evaluated by the naphthol AS-D chloroacetate technique, the administration of adenosine, YT-146, and CGS21680C significantly inhibited this increase. These findings suggest that adenosine reduces I/R-induced liver injury both by inhibiting the synthesis of inflammatory mediators and by inhibiting neutrophil degranulation directly, probably through A(2A)R stimulation.

Topics: Adenosine; Alkynes; Animals; Calcium; Cells, Cultured; Chemokine CXCL1; Chemokines, CXC; Chemotactic Factors; Growth Substances; Humans; Intercellular Signaling Peptides and Proteins; Ischemia; Leukocyte Elastase; Lipopolysaccharides; Liver; Male; Monocytes; Neutrophil Activation; Peroxidase; Phenethylamines; Purinergic P1 Receptor Agonists; Purinergic P1 Receptor Antagonists; Rats; Rats, Wistar; Receptor, Adenosine A2A; Reperfusion Injury; Triazines; Triazoles; Tumor Necrosis Factor-alpha

L-selectin plays an important role in the early phase of PMNs recruitment in the hepatic microvasculature following liver ischemia and reperfusion (I/R). Leukocyte cytokine chemoattractants (chemokines) cause polymorphonuclear neutrophil (PMN) activation in I/R injury. In this study, we examined the role of L-selectin in the production of chemokines in the liver and lung inflammatory response following 90 min of warm ischemia.. Thirty-six C57BL/6 mice were subjected to partial liver ischemia for a period of 90 min. Three groups of animals were included (n = 12 per group)-sham group, ischemic control, and the ischemic group receiving monoclonal antibody against L-selectin. We evaluated at 3 h: liver injury measurements, serum chemokines (MIP-2 and MIP-1alpha), liver and lung tissue myeloperoxidase (MPO), and liver and lung histology. Statistical analysis included ANOVA, Student-Newman-Keuls', and Kruskal-Wallis multiple comparison Z-value tests.. The ischemic group treated with anti-L-selectin showed significant decreases in liver enzyme levels and a marked decrease in serum MIP-2 (P < 0.05) when compared to ischemic controls. No reduction in serum MIP-1alpha was noted; however, neutrophil infiltration was significantly ameliorated in the liver and in the lung, as reflected by decreased MPO levels (P < 0.05). Improved histopathological features were observed in the anti-L-selectin-treated group compared to ischemic controls in the liver and the lung.. Our study suggests an important role for L-selectin in the pathogenesis of liver I/R and the production of chemokines. Anti-L-selectin treatment resulted in improved liver function, decreased neutrophil infiltration, and decreased MIP-2 chemokine response.

Topics: Animals; Chemokine CCL3; Chemokine CCL4; Chemokine CXCL2; Ischemia; L-Selectin; Liver; Macrophage Inflammatory Proteins; Mice; Mice, Inbred C57BL; Monokines; Peroxidase; Reperfusion Injury

The purpose of this study was to compare protective effects of AMP579 and adenosine (Ado) at reperfusion (R) on inhibition of polymorphonuclear neutrophil (PMN) activation, PMN-mediated injury to coronary artery endothelium, and final infarct size.. In anesthetized dogs, 1 h of left anterior descending coronary artery occlusion was followed by 24 h R and drugs were administered at R. Control (n=8, saline control), AMPI (n=7, AMP579, 50 microg/kg i.v. bolus followed by 3 microg/kg/min for 2 h), AMPII (n=7, AMP579, 50 microg/kg i.v. bolus), AMPIII (n=7, AMP579, 3 microg/kg/min i.v. for 2 h), and Ado (n=7, adenosine, 140 microg/kg/min i.v. for 2 h).. AMP579 in vitro directly inhibited superoxide radical (O(-)(2)) generation (nM/5x10(6) PMNs) from PMNs dose-dependently (from 17+/-1* at 10 nM to 2+/-0.2* at 10 microM vs. activated 30+/-2). However, inhibition of O(-)(2) generation by Ado at each concentration was significantly less than for AMP579. The IC(50) value for AMP579 (0.09+/-0.02 microM) on O(-)(2) generation was significantly less than that of Ado (3.9+/-1. 1 microM). Adherence of unstimulated PMN to postischemic coronary artery endothelium (PMNs/mm(2)) was attenuated in AMPI and AMPIII vs. Control (60+/-3* and 58+/-3* vs. Control 110+/-4), while Ado partially attenuated PMN adherence (98+/-3*). Accordingly, endothelial-dependent vascular relaxation was significantly greater in AMPI and AMPIII vs. Ado. At 24 h R, myocardial blood flow (MBF, ml/min/g) in the area at risk (AAR), confirmed by colored microspheres, in AMPI and AMPIII was significantly improved (0.8+/-0. 1* and 0.7+/-0.1* vs. Control 0.3+/-0.04). Infarct size (IS, TTC staining) in AMPI and AMPIII was significantly reduced from 38+/-3% in Control to 21+/-4%* and 22+/-3%*, respectively, confirmed by lower plasma creatine kinase activity (I.U./g protein) in these two groups (27+/-6* and 32+/-2* vs. 49+/-3). Cardiac myeloperoxidase activity (MPO, Abs/min) in the AAR was significantly reduced in AMPI and AMPIII vs. Control (36+/-11* and 35+/-10* vs. 89+/-10). However, changes in MBF, IS and MPO were not significantly altered by Ado.. These data suggest that continuous infusion of AMP579 at R is more potent than adenosine in attenuating R injury, and AMP579-induced cardioprotection involves inhibition of PMN-induced vascular and myocardial tissue injury. *P<0.05 vs. Control.

Topics: Adenosine; Analysis of Variance; Animals; Cell Adhesion; Cells, Cultured; Creatine Kinase; Dogs; Dose-Response Relationship, Drug; Endothelium, Vascular; Female; Imidazoles; Male; Myocardial Reperfusion Injury; Myocardium; Neutrophils; Peroxidase; Pyridines; Random Allocation; Receptors, Purinergic P1; Regional Blood Flow; Reperfusion Injury; Superoxides; Time Factors; Water

Peroxynitrite-mediated DNA strand breaks trigger poly (ADP-ribose) synthetase (PARS) activation, resulting in intracellular energetic failure and organ dysfunction. We investigated the role of PARS activation on the inflammatory and functional response of the intestine to mesenteric ischemia-reperfusion injury. Anesthetized rats exposed to 15 min occlusion of the superior mesenteric artery showed an increased mucosal PARS activity (ex vivo incorporation of radiolabelled NAD+ in gut mucosal scrapings) as soon as 10 min after reperfusion. During the first 30 min of reperfusion, significant mucosal damage developed, as well as mucosal hyperpermeability to a 4000 MW fluorescent dextran (FD4). These alterations were significantly reduced by treatment with the NO synthase inhibitor L-NMA, which blocks the production of peroxynitrite, as well as with the PARS inhibitors 3-aminobenzamide and nicotinamide, whereas they were markedly enhanced by the glutathione depletor L-buthionine-(S,R)-sulfoximine. Also, PARS inhibition significantly reduced ileal neutrophil infiltration (myeloperoxidase activity) at 3 h reperfusion. In a second set of experiments, the effects of 15 or 30 min ischemia followed by 3 h reperfusion were evaluated in PARS knockout and wild-type mice. Significant protection against histological damage, neutrophil infiltration, and mucosal barrier failure (evaluated by the mucosal-to-serosal FD4 clearance of everted ileal sacs incubated ex vivo) was noted in PARS knockout mice, who also showed reduced alterations in remote organs, as shown by lesser lipid peroxidation (malondialdehyde formation) and neutrophil infiltration in the lung and liver. In conclusion, PARS plays a crucial role in mediating intestinal injury and dysfunction in the early and late phases of mesenteric reperfusion. Pharmacological inhibition of PARS may be a novel approach to protect tissues from reperfusion-related damage.

Topics: Animals; Arterial Occlusive Diseases; Chemotaxis, Leukocyte; DNA Damage; Energy Metabolism; Enzyme Induction; Enzyme Inhibitors; Ileum; Intestinal Mucosa; Ischemia; Lipid Peroxidation; Liver; Lung; Male; Mesenteric Artery, Superior; Mesentery; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophil Infiltration; Neutrophils; Nitrates; Nitric Oxide Synthase; omega-N-Methylarginine; Oxidative Stress; Peroxidase; Poly(ADP-ribose) Polymerases; Rats; Rats, Wistar; Reperfusion Injury

The aim of the present study was to investigate the effects of tempol, a membrane-permeable radical scavenger, in rats subjected to splanchnic artery occlusion shock (SAO). Rats subjected to SAO developed a significant decrease in mean arterial blood pressure, a significant increase in tissue myeloperoxidase activity, and a marked injury to the distal ileum. SAO shock resulted in 100% mortality at 2 h after reperfusion. At 60 min after reperfusion, a marked increase in the immunoreactivity to nitrotyrosine and to poly (ADP-ribose) synthetase was observed in the necrotic ileum of rats with SAO. Staining of sections of the ileum obtained from SAO-shocked rats with anti-intercellular adhesion molecule (ICAM-1) and anti-P-selectin antibodies resulted in diffuse staining. Tempol (30 mg/kg bolus injection 5 min prior to reperfusion, followed by an infusion of 30 mg/kg/h intravenously) attenuated 1) the infiltration of the reperfused intestine with neutrophils, 2) the lipid peroxidation, 3) the production of peroxynitrite, 4) the degree of P-selectin and ICAM-1 staining in tissue sections from SAO-shocked rats, 5) histological signs of bowel injury, and 6) mortality at 2 h after reperfusion. Taken together, our results clearly demonstrate that the intracellular radical scavenger tempol reduces the intestinal injury of rats subjected SAO shock.

Topics: Animals; Arterial Occlusive Diseases; Celiac Artery; Cell Membrane Permeability; Constriction; Cyclic N-Oxides; Drug Evaluation, Preclinical; Enzyme Induction; Free Radical Scavengers; Ileum; Intercellular Adhesion Molecule-1; Lipid Peroxidation; Male; Malondialdehyde; Mesenteric Artery, Superior; Nitrates; P-Selectin; Peroxidase; Poly(ADP-ribose) Polymerases; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Spin Labels; Splanchnic Circulation

A central role for nuclear factor-kappaB (NF-kappaB) in the induction of lung inflammatory injury is emerging. We hypothesized that NF-kappaB is a critical early regulator of the inflammatory response in lung ischemia-reperfusion injury, and inhibition of NF-kappaB activation reduces this injury and improves pulmonary graft function. With use of a porcine transplantation model, left lungs were harvested and stored in cold Euro-Collins preservation solution for 6 h before transplantation. Activation of NF-kappaB occurred 30 min and 1 h after transplant and declined to near baseline levels after 4 h. Pyrrolidine dithiocarbamate (PDTC), a potent inhibitor of NF-kappaB, given to the lung graft during organ preservation (40 mmol/l) effectively inhibited NF-kappaB activation and significantly improved lung function. Compared with control lungs 4 h after transplant, PDTC-treated lungs displayed significantly higher oxygenation, lower PCO(2), reduced mean pulmonary arterial pressure, and reduced edema and cellular infiltration. These results demonstrate that NF-kappaB is rapidly activated and is associated with poor pulmonary graft function in transplant reperfusion injury, and targeting of NF-kappaB may be a promising therapy to reduce this injury and improve lung function.

Topics: Animals; DNA; Female; I-kappa B Proteins; Lung; Lung Transplantation; Male; NF-kappa B; Peroxidase; Postoperative Complications; Pulmonary Circulation; Pulmonary Edema; Pyrrolidines; Reperfusion Injury; Swine; Thiocarbamates

Ischemia-reperfusion injury after lung transplantation involves the generation of free radicals. Captopril has been shown to be protective in models of ischemia-reperfusion injury in other organs by acting as a free radical scavenger. The purpose of this study was to assess the protective effects of captopril against ischemia-reperfusion injury and to evaluate the ability of captopril to scavenge free radicals and inhibit neutrophil activation in an experimental model of lung transplantation.. A rat single-lung transplant model was used. Donor lungs were flushed and preserved in low-potassium dextran-glucose solution with (n = 5) and without captopril (500 micromol/L; n = 5) for 18 hours at 4 degrees C and then transplanted and reperfused for 2 hours. At the conclusion of the 2-hour reperfusion period, arterial blood gases, blood pressure, and peak airway pressure were measured. Lung tissue biopsy specimens were obtained for assessment of wet/dry weight ratios, histology, and neutrophil sequestration (myeloperoxidase activity). Lipid peroxidation (F(2)-isoprostane assay) was analyzed from plasma samples and tissue lysates.. The addition of captopril to the lung preservation solution significantly improved postreperfusion PO (2) (312 +/- 63.3 mm Hg vs 202 +/- 21.1 mm Hg; P =.006), peak airway pressure (11.4 +/- 1.1 cm H(2)O vs 15.6 +/- 1.5 cm H(2)O; P =.001), and wet/dry weight ratio (4.9 +/- 0.4 vs 15.8 +/- 10.9; P =.008). Blood pressures did not differ significantly between groups. No significant differences were seen in myeloperoxidase activity or F(2)-isoprostane levels.. The use of captopril in the preservation solution ameliorates ischemia-reperfusion injury in transplanted lungs after an extended cold preservation period. The mechanisms by which captopril is protective remain elusive but do not appear to include inhibition of neutrophil sequestration or lipid peroxidation. This novel approach to ischemia-reperfusion injury may lead to improved lung function after transplantation and provide further insight into the pathogenesis of acute lung injury.

Topics: Angiotensin-Converting Enzyme Inhibitors; Animals; Blood Pressure; Captopril; Dextrans; Dinoprost; F2-Isoprostanes; Free Radical Scavengers; Glucose; Lung; Lung Transplantation; Male; Neutrophil Activation; Organ Preservation; Oxygen; Peroxidase; Rats; Rats, Inbred Lew; Reperfusion Injury; Systole

Splanchnic artery occlusion shock (SAO) causes an enhanced formation of reactive oxygen species (ROS), which contribute to the pathophysiology of shock. Here we have investigated the effects of n-acetylcysteine (NAC), a free radical scavenger, in rats subjected to SAO shock.. Treatment of rats with NAC (applied at 20 mg/kg, 5 min prior to reperfusion, followed by an infusion of 20 mg/kg/h) attenuated the mean arterial blood and the migration of polymorphonuclear cells (PMNs) caused by SAO-shock. NAC also attenuated the ileum injury (histology) as well as the increase in the tissue levels of myeloperoxidase (MPO) and malondialdehyde (MDA) caused by SAO shock in the ileum. There was a marked increase in the oxidation of dihydrorhodamine 123 to rhodamine in the plasma of the SAO-shocked rats after reperfusion. Immunohistochemical analysis for nitrotyrosine and for poly(ADP-ribose) synthetase (PARS) revealed a positive staining in ileum from SAO-shocked rats. The degree of staining for nitrotyrosine and PARS were markedly reduced in tissue sections obtained from SAO-shocked rats which had received NAC. Reperfused ileum tissue sections from SAO-shocked rats showed positive staining for P-selectin, which was mainly localised in the vascular endothelial cells. Ileum tissue section obtained from SAO-shocked rats with anti-intercellular adhesion molecule (ICAM-1) antibody showed a diffuse staining. NAC treatment markedly reduced the intensity and degree of P-selectin and ICAM-1 in tissue section from SAO-shocked rats. In addition, in ex vivo studies in aortic rings from shocked rats, we found reduced contractions to noradrenaline and reduced responsiveness to a relaxant effect to acetylcholine (vascular hyporeactivity and endothelial dysfunction, respectively). NAC treatment improved contractile responsiveness to noradrenaline, enhanced the endothelium-dependent relaxations and significantly improved survival.. Taken together, our results clearly demonstrate that NAC treatment exert a protective effect and part of this effect may be due to inhibition of the expression of adhesion molecule and peroxynitrite-related pathways and subsequent reduction of neutrophil-mediated cellular injury.

Topics: Acetylcholine; Acetylcysteine; Analysis of Variance; Animals; Aorta; Fluorescent Antibody Technique, Indirect; Free Radical Scavengers; Ileum; In Vitro Techniques; Intercellular Adhesion Molecule-1; Leukocyte Count; Lipid Peroxidation; Male; Malondialdehyde; Nitrates; Nitrites; P-Selectin; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Splenic Artery; Tyrosine; Vasodilation

There is evidence that the excessive generation of reactive-oxygen radicals contributes to the brain injury associated with transient, cerebral ischemia. This study investigates the effects of tempol, a small, water-soluble molecule, that crosses biological membranes, on the brain injury caused by bilateral occlusion and reperfusion of both common carotid arteries in the gerbil (BCO). Treatment of gerbils with tempol (30 mg/kg i.p. at 30 min prior to reperfusion and at 1 and 6 h after the onset of reperfusion) reduced the formation of post-ischemic brain oedema. Tempol also attenuated the increase in the cerebral levels of malondialdehyde (MDA) and the hippocampal levels of myeloperoxidase (MPO) caused by cerebral ischemia and reperfusion. The immunohistochemical analysis of the hippocampal region of brains subjected to ischemia-reperfusion exhibited positive staining for nitrotyrosine (an indicator of the generation of peroxynitrite) and poly(ADP-ribose) synthetase (PARS) (an indicator of the activation of this nuclear enzyme secondary to single strand breaks in DNA). In gerbils subjected to BCO, which were treated with tempol, the degree of staining for nitrotyrosine and PARS was markedly reduced. Tempol increased survival and reduced the hyperactivity (secondary to the ischemia-induced neurodegeneration) caused by cerebral ischemia and reperfusion. The loss of neurons from the pyramidal layer of the CA1 region caused by ischemia and reperfusion was also attenuated by treatment of gerbils with tempol. This is the first evidence that the membrane-permeable, radical scavenger tempol reduces the cerebral injury caused by transient, cerebral ischemia in vivo.

Topics: Animals; Arterial Occlusive Diseases; Brain; Brain Edema; Cerebral Arteries; Cyclic N-Oxides; Free Radical Scavengers; Gerbillinae; Hippocampus; Lipid Peroxides; Male; Malondialdehyde; Motor Activity; Neutrophil Infiltration; Nitrates; Nitrites; Peroxidase; Poly(ADP-ribose) Polymerases; Reperfusion Injury; Spin Labels; Survival Analysis; Tyrosine

Reperfusion of ischemic vascular beds may lead to recruitment and activation of leukocytes, release of mediators of the inflammatory process and further injury to the affected vascular bed and to remote sites. Neutrophils appear to play a major role in the pathophysiology of reperfusion injury. Amongst inflammatory mediators shown to activate neutrophils and induce their recruitment in vivo, much interest has been placed on the role of leukotriene (LT)B(4). Here, we have assessed the effects of the BLT receptor antagonist (+)-1-(3S, 4R)-[3-(4-phenyl-benzyl)-4-hydroxy-chroman-7-yl]-cyclopentane carboxylic acid (CP 105,696) in a model of neutrophil-dependent ischemia and reperfusion injury in the rat. The superior mesenteric artery was isolated and ischemia was induced by its total occlusion for 30 min. After 30 min of reperfusion, injury was assessed by evaluating the extravasation of Evans blue, an index of vascular permeability, and the levels of myeloperoxidase, an index of neutrophil accumulation, in the intestine, mesentery and lung. The neutrophil-dependence of the local (intestine and mesentery) and remote (lung) injury was confirmed by using fucoidin, a selectin blocker, and WT-3, an anti-CD18 monoclonal antibody. Post-ischemic treatment with CP 105,696 dose-dependently inhibited vascular permeability and neutrophil accumulation in the intestine and mesentery. CP 105,696 also blocked the vascular permeability changes, but not neutrophil accumulation, in the lungs after reperfusion injury. Virtually identical results were obtained with another BLT receptor antagonist, 1-(5-ethyl-2-hydroxy-4-(6-methyl-6-(1H-tetrazol-5-yl)-heptoxy++ +)-phenyl )ethanone (LY255283). Our results suggest that post-ischemic treatment with BLT receptor antagonists may inhibit local and remote ischemia and reperfusion injury by blocking both the accumulation and/or activation of neutrophils.

Topics: Animals; Antibodies, Monoclonal; Benzopyrans; Capillary Permeability; Carboxylic Acids; CD18 Antigens; Disease Models, Animal; Dose-Response Relationship, Drug; Evans Blue; Intestinal Mucosa; Intestines; Leukotriene Antagonists; Lung; Male; Mesenteric Artery, Superior; Mesentery; Neutrophils; Peroxidase; Polysaccharides; Rats; Rats, Wistar; Receptors, Leukotriene B4; Reperfusion Injury; Tetrazoles

Alterations in nitric oxide synthesis, endothelial adhesivity and pulmonary hemodynamics are investigated in an animal model of lung ischemia-reperfusion.. Two sets of rats, each containing seven animals, were either subjected to unilateral pulmonary ischemia and reperfusion (Study Group) or underwent the same surgical procedure without ischemia (Control Group). Pulmonary artery pressure (PAP), pulmonary blood flow (PBF) trend, NOS-2, intercellular adhesion molecule-1 (ICAM-1), myeloperoxidase (MPO) and cGMP expression of the reperfused lung tissue and, final paO(2) were compared between the two groups.. ICAM-1 expression was increased (369+/-114 vs. 115+/-65; P=0.02), NOS-2 expression and tissue cGMP levels were decreased (377+/-44 vs. 452+/-54; P=0.03 and 7.8+/-3.5 vs. 9.4+/-2.3 pmol/ml; P=0.03, respectively) and MPO activity was increased (2.7+/-0.9-3.5+/-0.8; P=0.03) in the reperfused lungs. Pulmonary artery pressure was 15+/-7 mmHg in the Control Group vs. 22+/-16 mmHg in the Study Group (P=0.04) at the 30th min of reperfusion. Pulmonary blood flow was greater in the Study Group at the beginning of reperfusion (9.5+/-4.1 vs. 7.1+/-3.1 ml/min at the 30th min) but considerably reduced thereafter (3.2+/-1. 4 vs. 6.2+/-2.1 at the 60th minute and 2.9+/-1.6 vs. 5.8+/-1.9 at the 120th min). At the end of the experiment, paO(2) was 95+/-30 in the Control Group vs. 71+/-32 in the Study Group (P=0.03).. These data establish that nitric oxide synthesis was suppressed after reperfusion. Pulmonary blood flow was first increased and then reduced. A parallel increase in MPO and ICAM-1 indicated proinflammatory reaction. Decreased tissue cGMP level was consistent with the suppressed NOS-2 production. Organ function was negatively influenced as represented by the decreased oxygenation, probably due to no-reflow phenomenon.

Topics: Animals; Biomarkers; Blood Flow Velocity; Blotting, Western; Cell Adhesion; Cyclic GMP; Endothelium, Vascular; Intercellular Adhesion Molecule-1; Leukocytes; Lung; Male; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxidase; Pulmonary Circulation; Pulmonary Wedge Pressure; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Leukocyte adhesion/infiltration in response to renal ischaemia/reperfusion (I/R) injury is a well-known but poorly understood phenomenon. The identification, kinetics, and exact role of these inflammatory cells in I/R injury and regeneration are still matters of debate.. Uninephrectomized rats were submitted to 60 min renal ischaemia by clamping of renal vessels.. Severe acute renal failure was observed, with maximum functional impairment on day 2. By 12 h after the ischaemic event, up to 80% of proximal tubular cells in the outer stripe of outer medulla (OSOM) were already severely damaged. Proliferation (proliferating cell nuclear antigen (PCNA) staining) started after 24 h, reaching maximum activity on day 3. Regeneration of tubular morphology started on the 3rd day, and after 10 days 50% of tubules had regenerated completely. Interstitial leukocytes (OX-1 immunohistochemical staining) were already prominent at day 1, thereafter gradually increasing with time. The so-called neutrophil-specific identification methods (myeloperoxidase (MPO), chloroacetate esterase, mAb HIS-48) proved to be non-specific, since they also stained for macrophages, as demonstrated by flow cytometry and the combination of these stainings with the macrophage-specific ED-1 staining. MPO activity was already significantly increased at 1 h post-I/R (439+/-34%, P<0.005), reaching its maximum activity after 12 h of I/R (1159+/-138%, P<0.0005), declining thereafter. On the other hand, neutrophil presence investigated by H&E staining revealed only a few neutrophils in glomeruli, medullary rays, and OSOM at 24 h after the ischaemic event (4.7+/-4.2 cells/mm(2) vs controls=2.3+/-2.0 cells/mm(2) (n.s.)), and remained unchanged over the next 10 days. In contrast, significant monocyte/macrophage adhesion/infiltration (ED-1 staining) occurred at the OSOM at 24 h post-ischaemia (at 24 h, 120+/-46 cells/mm(2) vs. sham=18+/-4 cells/mm(2) (P<0.05)), became prominent at day 5 (1034+/-161 cells/mm(2) vs sham=18+/-18 cells/mm(2) (P<0.05)), and almost disappeared after 10 days. CD4(+) cells (W3/25) gradually increased from day 5, reaching a maximum at day 10. A few CD8(+) cells (OX-8) were apparent from days 3 until 10, but no B-cells (OX-33) were observed.. After severe warm I/R renal injury, a pronounced acute tubular necrosis occurs during the first 12-24 h in the absence of a marked cellular infiltrate, but with an important renal MPO activity, reflecting the activation of the adhering inflammatory cells (polymorphonuclear cells (PMNs) and mainly monocytes/macrophages). Only later at the time and site (OSOM) of regeneration a sequential accumulation of monocytes/macrophages and T cells becomes prominent, in contrast with the low number of neutrophils found in the kidney during the 10-day post-ischaemic period. The non-specificity of the so-called neutrophil-specific identification methods (MPO activity, naphthol AS-D chloroacetate esterase, or mAb HIS-48 staining), cross-reacting with monocytes/macrophages, explains the controversy in literature concerning the number of PMNs in post-ischaemic injury.

Topics: Animals; Blood Cells; Extracellular Space; Ischemia; Kidney; Kidney Medulla; Kinetics; Leukocytes; Macrophages; Male; Monocytes; Peroxidase; Proliferating Cell Nuclear Antigen; Rats; Rats, Inbred Lew; Regeneration; Renal Circulation; Reperfusion Injury; Staining and Labeling

Carvedilol, a selective alpha(1) and non-selective beta-adrenoceptor antagonist and antioxidant, has been shown to provide significant cardiac protection in animal models of myocardial ischemia. To further explore the mechanisms contributing to the efficacy of carvedilol cardioprotection, the effects of carvedilol on hemodynamic variables, infarct size and myeloperoxidase activity (an index of neutrophil accumulation) were compared with a beta(1) selective adrenoceptor antagonist, bisoprolol. Carvedilol (1 mg/kg) or bisoprolol (1 mg/kg) was given intravenously 5 min before reperfusion. In vehicle-treated rabbits, ischemia (45 min) and reperfusion (240 min) resulted in significant increases in left ventricular end diastolic pressure, large myocardial infarction (64.7+/-2.6% of area-at-risk) and a marked increase in myeloperoxidase activity (64+/-14 U/g protein in area-at-risk). Carvedilol treatment resulted in sustained reduction of the pressure-rate-index and significantly smaller infarcts (30+/-2.9, P<0.01 vs. vehicle) as well as decreased myeloperoxidase activity (26+/-11 U/g protein in area-at-risk, P<0.01 vs. vehicle). Administration of bisoprolol at 1 mg/kg resulted in a pressure-rate-index comparable to that of carvedilol and also decreased infarct size (48.4+/-2.5%, P<0.001 vs. vehicle, P<0.05 vs. carvedilol), although to a significantly lesser extent than that observed with carvedilol. Treatment with bisoprolol failed to reduce myeloperoxidase activity in the ischemic myocardial tissue. In addition, carvedilol, but not bisoprolol, markedly decreased cardiac membrane lipid peroxidation measured by thiobarbituric acid formation. Taken together, this study suggests that the superior cardioprotection of carvedilol over bisoprolol is possibly the result of carvedilol's antioxidant and anti-neutrophil effects, not its hemodynamic properties.

Topics: Adrenergic beta-Agonists; Adrenergic beta-Antagonists; Animals; Antioxidants; Bisoprolol; Carbazoles; Cardiovascular Agents; Carvedilol; Creatine Kinase; Disease Models, Animal; Dose-Response Relationship, Drug; Heart Rate; Isoproterenol; Lipid Peroxidation; Male; Membrane Lipids; Myocardial Ischemia; Myocardium; Peroxidase; Propanolamines; Rabbits; Reperfusion Injury; Ventricular Pressure

The objective of this study was to examine the feasibility of human interleukin 10 gene transfer into rat lung isografts and to investigate the effect of gene transfer on subsequent ischemia-reperfusion injury.. Male F344 rats were divided into 4 groups and underwent left lung isotransplantation. Twenty-four hours before harvest, 5 x 10E9 pfu (group I, n = 6) or 1 x 10E10 pfu (group II, n = 7) of AdRSVhIL-10 was intravenously administered to donor rats. In group I-C (n = 6) and group II-C (n = 6), serving as controls, 5 x 10E9 pfu and 1 x 10E10 pfu of AdCMVLacZ were administered, respectively. Grafts were preserved for 18 hours at 4 degrees C before implantation and assessed 24 hours after reperfusion. Transgene expression of human interleukin 10 was assessed by both reverse transcriptase-polymerase chain reaction and immunohistochemistry. Graft inducible nitric oxide synthase, tumor necrosis factor alpha, intercellular adhesion molecule-1, growth-regulated gene product/cytokine-induced neutrophil chemoattractant-1, and monocyte chemotactic protein-1 mRNA expression were assessed by reverse transcriptase-polymerase chain reaction. Isograft gas exchange, exhaled nitric oxide, and myeloperoxidase activity were also analyzed.. Dose-dependent transgene expression was detected by reverse transcriptase-polymerase chain reaction and immunohistochemistry. Arterial PO (2) in groups I (164.72 +/- 85.3 mm Hg) and II (153.19 +/- 113 mm Hg) was significantly higher than in groups I-C (82.37 +/- 19.1 mm Hg) and II-C (77.95 +/- 33.4 mm Hg) (P =.022 and P =.031, respectively). Arterial PCO (2) in group I (33.40 +/- 6.80 mm Hg) was significantly lower than in group I-C (51.23 +/- 11.9 mm Hg) (P =.0096). Myeloperoxidase activity in group II (0.083 +/- 0.031 DeltaOD. min(-1). mg(-1)) was significantly lower than in group II-C (0.117 +/- 0.028 DeltaOD. min(-1). mg(-1)) (P =.044). The inducible nitric oxide synthase mRNA expression in group II (0.627 +/- 0.28) was significantly lower than in group II-C (1.125 +/- 0.63) (P =. 039).. Adenovirus-mediated human interleukin 10 gene transfer in vivo into lung isografts ameliorates subsequent ischemia-reperfusion injury. This results in improved graft gas exchange, reduced neutrophil sequestration, and down-regulation of graft inducible nitric oxide synthase mRNA expression.

Topics: Adenoviridae; Analysis of Variance; Animals; Down-Regulation; Feasibility Studies; Gene Expression; Gene Transfer Techniques; Genetic Vectors; Humans; Immunohistochemistry; Interleukin-10; Lung; Lung Transplantation; Male; Nitric Oxide Synthase; Peroxidase; Rats; Rats, Inbred F344; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger

We sought to determine the mechanisms responsible for the reduced renal tissue injury by agonists of A(2A) adenosine receptors (A(2A)-ARs) in models of ischemia-reperfusion (I/R) injury. DWH-146e, a selective A(2A)-AR agonist, was administered subcutaneously to Sprague-Dawley rats and C57BL/6 mice via osmotic minipumps, and animals were subjected to I/R. I/R led to an increase in plasma creatinine and kidney neutrophil infiltration. Infusion of DWH-146e at 10 ng. kg(-1). min(-1) produced a 70% reduction in plasma creatinine as well as a decrease in neutrophil density in outer medulla and cortex and myeloperoxidase activity in the reperfused kidney. Myeloperoxidase activity in kidney correlated with the degree of renal injury. P-selectin and intercellular adhesion molecule 1 (ICAM-1) immunoreactivity were most prominent in endothelial cells of peritubular capillaries and interlobular arteries of cortex and outer and inner medulla of vehicle-treated mice whose kidneys were subjected to I/R. DWH-146e treatment led to a pronounced decrease in P-selectin- and ICAM-1-like immunoreactivity. These data are consistent with our hypothesis that A(2A)-AR agonists limit I/R injury due to an inhibitory effect on neutrophil adhesion.

Topics: Acute Kidney Injury; Animals; Cell Adhesion; Cell Count; Creatinine; Cytoprotection; Disease Models, Animal; Injections, Subcutaneous; Intercellular Adhesion Molecule-1; Kidney; Male; Mice; Mice, Inbred C57BL; Neutrophil Infiltration; P-Selectin; Peroxidase; Purinergic P1 Receptor Agonists; Rats; Rats, Sprague-Dawley; Receptor, Adenosine A2A; Receptors, Purinergic P1; Reperfusion Injury

Recent studies have demonstrated that melatonin is a scavenger of oxyradicals and peroxynitrite and an inhibitor of nitric oxide (NO) production. NO, peroxynitrite (formed from NO and superoxide anion), and poly (ADP-Ribose) synthetase (PARS) have been implicated as mediators of neuronal damage following focal ischemia. In the present study, we have investigated the effects of melatonin treatment in Mongolian gerbils subjected to cerebral ischemia. Treatment of gerbils with melatonin (10 mg kg(-1), 30 min before reperfusion and 1, 2, and 6 hr after reperfusion) reduced the formation of post-ischemic brain edema, evaluated by water content. Melatonin also attenuated the increase in the brain levels malondialdehyde (MDA) and the increase in the hippocampus of myeloperoxidase (MPO) caused by cerebral ischemia. Positive staining for nitrotyrosine was found in the hippocampus of Mongolian gerbils subjected to cerebral ischemia. Hippocampus tissue sections, from Mongolian gerbils subjected to cerebral ischemia, also showed positive staining for PARS. The degrees of staining for nitrotyrosine and for PARS were markedly reduced in tissue sections obtained from animals that received melatonin. Melatonin treatment increased survival and reduced hyperactivity linked to neurodegeneration induced by cerebral ischemia and reperfusion. Histological observations of the pyramidal layer of CA-1 showed a reduction of neuronal loss in animals that received melatonin. These results show that melatonin improves brain injury induced by transient cerebral ischemia.

Topics: Animals; Brain; Brain Edema; Brain Ischemia; Enzyme-Linked Immunosorbent Assay; Free Radical Scavengers; Gerbillinae; Immunoenzyme Techniques; Male; Malondialdehyde; Melatonin; Motor Activity; Nitrates; Nitrites; Oxidative Stress; Peroxidase; Poly(ADP-ribose) Polymerases; Reperfusion Injury; Tyrosine

Lipid microbubbles used for perfusion imaging with ultrasound are retained within inflamed tissue because of complement-mediated attachment to leukocytes within venules. We hypothesized that incorporation of phosphatidylserine (PS) into the microbubble shell may enhance these interactions by amplifying complement activation and thereby allow ultrasound imaging of inflammation.. In 6 mice, intravital microscopy of tissue necrosis factor-alpha-treated cremaster muscle was performed to assess the microvascular behavior of fluorescein-labeled lipid microbubbles with and without PS in the shell. Ten minutes after intravenous injection, microbubble attachment to leukocytes within inflamed venules was greater for PS-containing than for standard lipid microbubbles (20+/-4 versus 10+/-3 per 20 optical fields, P<0.05). The ultrasound signal from retained microbubbles was assessed in the kidneys of 6 mice undergoing renal ischemia-reperfusion injury and in 6 control kidneys. The signal from retained microbubbles in control kidneys was low (<2.5 video intensity units) for both agents. After ischemia-reperfusion, the signal from retained microbubbles was 2-fold higher for PS-containing than for standard lipid microbubbles (18+/-6 versus 8+/-2 video intensity units, P<0.05). An excellent relation was found between the ultrasound signal from retained microbubbles and the degree of renal inflammation, assessed by tissue myeloperoxidase activity.. -We conclude that noninvasive assessment of inflammation is possible by ultrasound imaging of microbubbles targeted to activated leukocytes by the presence of PS in the lipid shell.

Topics: Animals; Blood Flow Velocity; Flow Cytometry; Inflammation; Kidney; Kidney Diseases; Leukocytes; Mice; Mice, Inbred C57BL; Neutrophil Infiltration; Peroxidase; Phosphatidylserines; Reperfusion Injury; Ultrasonography

The role of nitric oxide in the ischemic injury of the kidney is still controversial. The aim of this study was to reevaluate the beneficial effect of exogenous nitric oxide and define its effects as regulator of gene p53 expression and apoptosis in the ischemic renal injury.. Sprague-Dawley rats were subjected to 75 min of renal warm ischemia and contralateral nephrectomy. The animals were divided into six groups (n=6 per group): Two sham groups at 4 and 24 hr, two ischemic control (IC) at same times and two treated groups (Na-NP), studied at same intervals, where sodium nitroprusside (5 mg/kg) was given 15 min before reperfusion. The parameters evaluated included: serum creatinine, blood urea nitrogen, neutrophil infiltration determined by myeloperoxidase, gene p53 expression determined by reverse transcriptase polymerase chain reaction, apoptosis determined by peroxidase in situ technique and light histology.. There were significant improvements in serum creatinine and blood urea nitrogen at 24 hr in the NA-NP group when compared with the IC group (P<0.05). Myeloperoxidase levels were higher in the IC when evaluated against the Na-NP groups. Na-NP exhibited a downregulating effect in the expression of gene p53 when compared to the IC group. Apoptosis was more evident in the IC group and had moderately increased histological damage when compared to the Na-NP group.. Nitric oxide demonstrated a protective effect in the ischemic injury of the kidney and exerted an antiapoptotic action dowregulating the expression of gene p53.

Topics: Animals; Apoptosis; Gene Expression; Genes, p53; Kidney; Male; Nitric Oxide; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Prolonged periods of hepatic ischemia are associated with hepatocellular injury and distant organ dysfunction in experimental models. Neutrophils (PMN) and tumor necrosis factor (TNF)-alpha have been implicated, mostly because of their local deleterious effects on the hepatocyte after hepatic ischemia and reperfusion (I/R) injury. We hypothesize that topical hepatic hypothermia (THH) reduces ischemia and reperfusion-induced hepatic necrosis, PMN infiltration, TNF-alpha release, and consequent acute pulmonary injury.. Sprague-Dawley rats (250 to 300g) were evenly divided into three groups: 90 minutes of normothermic (37 degrees C) partial hepatic ischemia (normothermic I/R), 90 minutes of hypothermic (25 degrees C) partial hepatic ischemia (hypothermic I/R), and sham laparotomy (without ischemia). There were six animals in each experimental group per time point unless otherwise specified. Hepatic necrosis and PMN infiltration were evaluated and scored on hematoxylin and eosin-stained liver specimens 12 hours after reperfusion. Serum TNF-alpha levels were determined by ELISA at 0 minutes, 15 minutes, 30 minutes, 1 hour, and 12 hours postreperfusion. Pulmonary PMN infiltration and vascular permeability were measured by myeloperoxidase activity and Evans blue dye extravasation, respectively, to quantitate pulmonary injury 12 hours after reperfusion.. Normothermic I/R results in a significant increase in TNF-alpha at 15 and 30 minutes (p < 0.005), PMN infiltration (p < 0.001), and hepatic necrosis (p < 0.001), compared with sham. Institution of THH reduced peak serum TNF-alpha levels by 54% at 15 minutes (p < 0.005) and by 73% at 30 minutes (p < 0.001) postreperfusion compared with normothermic I/R. Similarly, hepatic PMN infiltration and necrosis at 12 hours were reduced by 60% (p < 0.05) and 47% (p < 0.05), respectively. Myeloperoxidase activity and Evans blue extravasation (measures of acute lung injury) were reduced by 42% and 39%, respectively, with institution of THH compared with animals undergoing normothermic I/R (p < 0.001).. These results demonstrate that THH protects the liver from ischemia and reperfusion-induced necrosis and PMN infiltration. In addition, THH reduces the serum levels of TNF-alpha and associated pulmonary injury. These data suggest that the ischemic liver is a potential source of inflammatory mediators associated with hepatic ischemia and reperfusion-induced pulmonary injury.

Topics: Analysis of Variance; Animals; Capillary Permeability; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Hypothermia, Induced; Liver; Male; Necrosis; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Respiratory Distress Syndrome; Severity of Illness Index; Time Factors; Tumor Necrosis Factor-alpha

To evaluate the degree of neutrophil infiltration into ischemic tissue after transient focal cerebral ischemia, and to examine the effects of chiral 3-n-butylphthalide (NBP) on this inflammatory process.. After a 24-h reperfusion following transient cerebral ischemia, two different techniques, histologic analysis and modified myeloperoxidase (MPO)-quantification method, were utilized to identify the infiltration of neutrophils into cerebral tissue following ischemia. The expression of intercellular adhesion molecule-1 (ICAM-1) and tumor necrosis factor-alpha(TNF-alpha) in the ischemic zone were observed by immunohistochemistry, Western blot, and in situ hybridization techniques.. In cerebral cortex area perfused by middle cerebral artery (MCA), MPO activity was greatly increased after 24 h of reperfusion in the vehicle group, and it correlated well with the infiltration of neutrophils. Administration of dl-, d-, and l-NBP (20 mg.kg-1) partially inhibited both the increase in MPO activity and the appearance of neutrophils in ischemia-reperfusion sites. Up-regulation of ICAM-1 was also observed on the microvessel endothelium in the ischemic territory. In addition, chiral NBP markedly blunted ICAM-1 expression, and decreased the number of TNF-alpha blue purple-positive neurons induced by ischemia-reperfusion injury.. The results indicate that the increase in neutrophils infiltration into the infarct site implicated postischemic brain injury, and NBP was effective in protecting the ischemic sites following ischemic insult.

Topics: Animals; Benzofurans; Brain Ischemia; Cerebral Cortex; Infarction, Middle Cerebral Artery; Inflammation; Intercellular Adhesion Molecule-1; Leukocyte Count; Male; Neuroprotective Agents; Neutrophils; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; RNA, Messenger; Tumor Necrosis Factor-alpha

A rat model of reversible occlusion of the middle cerebral artery was developed to assess the role of neutrophils and prophylactic hyperbaric oxygen (HBO2) on cerebral injury. Blood flow to the ipsilateral caudate putamen nucleus was reduced by approximately 50% during 2 h of arterial occlusion, but unaffected on the contralateral side. Neutrophil accumulation in brain was documented as myeloperoxidase concentration, which was elevated in both ipsilateral and contralateral cerebral hemispheres at 1 and 46 h after occlusion/reperfusion. HBO2 administered before ischemia at 2.8 atm abs for 45 min, as well as antibody-induced neutropenia, reduced neutrophil accumulation, functional neurologic deficits, and cerebral infarct volume. These data demonstrate that one mechanism for benefit of HBO2 is related to its ability to ameliorate post-ischemic injury by inhibiting neutrophil sequestration. This mechanism should be taken into consideration when choosing partial pressures of oxygen for investigational clinical protocols.

Topics: Analysis of Variance; Animals; Cell Movement; Cerebrovascular Circulation; Hyperbaric Oxygenation; Infarction, Middle Cerebral Artery; Male; Models, Animal; Neutropenia; Neutrophils; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Time Factors

Endothelium dysfunction with severe pulmonary hypertension may occur after total cardiopulmonary bypass (CPB) in infants as a result of a widespread inflammatory response. The aim of this study was to separate out the effects of lung ischemia-reperfusion from membrane oxygenator-induced activation of leukocytes on the function and viability of the pulmonary and systemic endothelia in neonatal piglets submitted to 90-min total CPB followed by 60-min reperfusion or in sham animals. Hemodynamics, gas exchange, endothelial-dependent relaxation in pulmonary and femoral arteries, and lung and skeletal muscle myeloperoxidase activity were assessed before, during, and after CPB, i.e., after reperfusion. Pulmonary and aortic endothelial cells and circulating leukocytes were harvested to assess reperfusion-induced changes in endothelial cells' viability and proliferation, and leukocyte-endothelial cell adhesion and cytotoxicity. Gas exchange worsened after reperfusion with pulmonary hypertension, increase in lung but not skeletal myeloperoxidase, and reduction of endothelial-dependent relaxation in pulmonary but not femoral arteries. After reperfusion, viabilities of pulmonary and aortic endothelial cells were reduced to 50%, endothelial cell growths were faster in pulmonary arteries than aorta, and leukocyte-pulmonary endothelial cell adhesion and cytotoxicity increased. These results suggest that in total CPB lung ischemia-reperfusion aggravates the inflammatory response and predisposes the lung endothelium to leukocyte-mediated injury.

Topics: Animals; Animals, Newborn; Aorta; Cardiopulmonary Bypass; Cell Division; Cell Survival; Cells, Cultured; Endothelium, Vascular; Femoral Artery; Hypertension, Pulmonary; Muscle, Skeletal; Neutrophils; Peroxidase; Pulmonary Artery; Reperfusion Injury; Swine; Vasodilation

Tumor necrosis factor alpha (TNF-alpha) has been shown to play a role in pulmonary injury after lower-extremity ischemia/reperfusion (I/R). However, its role in direct skeletal muscle injury is poorly understood. The hypothesis that endogenous TNF production contributes to skeletal muscle injury after hindlimb I/R in rats was tested.. Juvenile male Sprague-Dawley rats underwent 4 hours of bilateral hindlimb ischemia and 4 hours of reperfusion (IR) or sham operation (SHAM). A subset was treated with a soluble TNF receptor I construct (STNFRI, 10 mg/kg) 1 hour before ischemia (PRE) or at reperfusion (POST). Direct skeletal muscle injury (SMII) and muscle endothelial capillary permeability (MPI) were quantified by means of Tc99 pyrophosphate and I125 albumin uptake. Pulmonary neutrophil infiltration and hepatocellular injury were assessed by means of myeloperoxidase content (MPO) and aspartate aminotransferase (AST) concentrations, respectively. Serum TNF bioactivity was measured with the WEHI bioassay.. Hindlimb I/R (IR vs SHAM) resulted in a significant (P <.05) increase in the SMII (0.52 +/- 0.06 vs 0.07 +/- 0.01) and MPI (0.35 +/-.04 vs 0.06 +/- 0.01). Pretreatment with STNFRI (PRE vs IR) significantly ameliorated both SMII (0.30 +/- 0.05 vs 0.52 +/- 0.06) and MPI (0.23 +/- 0.02 vs 0.35 +/- 0.04), whereas treatment at reperfusion (POST vs IR) had no effect. Hindlimb I/R (IR vs SHAM) resulted in both significant pulmonary neutrophil infiltration (MPO 16.4 +/- 1.06 U/g vs 11.3 +/- 1.4 U/g) and hepatocellular injury (AST 286 +/- 45 U/mL vs 108 +/- 30 U/mL), but neither was inhibited by pretreatment with STNFRI before ischemia. Detectable levels of TNF were measured during ischemia in a significantly higher percentage of the IR group compared with SHAM (9 of 12 vs 3 of 12), and the maximal TNF values were also significantly greater (51.1 +/- 12.6 pg/mL vs 5.5 +/- 2.9 pg/mL). No TNF was detected in any treatment group during reperfusion nor after administration of the STNFRI.. Acute hindlimb IR initiates a systemic TNF response during the ischemic period that is partly responsible for the associated skeletal muscle injury.

Topics: Animals; Aspartate Aminotransferases; Capillary Permeability; Hindlimb; Liver; Lung; Male; Muscle, Skeletal; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

Although administration of the sialyl Lewis(x) oligosaccharide may reduce myocardial injury after ischemia-reperfusion, its effect on coronary and cerebral microvascular regulation and its clinical application during cardiac operation have not been examined.. Pigs were placed on normothermic cardiopulmonary bypass after 30 minutes of left anterior descending coronary artery occlusion. The hearts were then arrested with cold high potassium cardioplegia. After 1 hour the cross-clamp was removed and the pigs were weaned from cardiopulmonary bypass and perfused for an additional 1 hour. CY-1503 (a sodium salt of the sialyl Lewis(x) oligosaccharide, n = 6) was administered before reperfusion. Six other pigs received saline vehicle. Endothelium-dependent relaxation of precontracted coronary and brain arterioles (70 to 180 microm) to adenosine 5'-diphosphate and endothelium-independent relaxation to sodium nitroprusside were studied in vitro with videomicroscopy. Control values were obtained from uninstrumented pigs. Myeloperoxidase activity in the myocardium and brain was measured to quantify neutrophil infiltration. Cardiac function and perfusion were assessed by left ventricular systolic pressure, maximum rate of increase of left ventricular pressure, left anterior descending coronary artery blood flow and percent segmental shortening, and cerebral vascular resistance, internal carotid artery blood flow, and the constitutively expressed and inducible isoform of nitric oxide synthase mRNA were measured.. The impaired myocardial contractile function after ischemia and cardioplegia was not improved by administration of CY-1503. The reduced endothelium-dependent relaxation responses of coronary and brain arterioles during ischemia followed by cardioplegia and cardiopulmonary bypass were improved with CY-1503, but the altered pattern of organ perfusion was not improved. Myeloperoxidase activity was increased in the heart after ischemia-cardioplegia and in the brain after cardiopulmonary bypass. CY-1503 reduced myeloperoxidase activity in both the myocardium and in the brain. Expressions of myocardial inducible isoform or constitutively expressed nitric oxide synthase were not altered in the heart.. Although the sialyl Lewis(x) oligosaccharide does reduce neutrophil infiltration and endothelial injury in the coronary and cerebral microcirculation after cardiopulmonary bypass, it does not have significant beneficial acute effects on organ perfusion or function in the myocardium or brain.

Topics: Animals; Brain; Cardiopulmonary Bypass; Endothelium, Vascular; Female; Hemodynamics; Leukocytes, Mononuclear; Male; Microcirculation; Myocardial Contraction; Myocardial Reperfusion Injury; Myocardium; Neutrophils; Oligosaccharides; Peroxidase; Reperfusion Injury; Swine; Vasodilation

We investigated the effect of antithrombin III on 60 min warm intestinal ischemia-reperfusion (IR) injury in rats. Sprague-Dawley rats, weighing 220-250 g, were divided into three groups: group 1 sham-operated group (no IR injury, n = 8), group 2 ischemic control group (control, Ringer's lactate infused, n = 8), group 3 Antithrombin III treated group (250 U/kg before ischemia, n = 8). Intestinal ischemia was induced in rats by occluding the superior mesenteric artery for 60 min. Malondialdehyde (MDA) levels, myeloperoxidase activity (MPO) and mucosal damage were investigated after 120 min reperfusion. Elevated MDA levels and MPO activity and severe histopathological damage were observed in the control group compared with the sham group (P < 0.05). Decreased MDA levels and MPO activity and less histopathological damage were detected in group 3 compared with the control group (P < 0.05). Accumulation of lipid peroxidation products and neutrophils in mucosal tissues were significantly inhibited by antithrombin III treatment. We conclude that treatment with antithrombin III before intestinal ischemia prevents histological damage in rats.

Topics: Animals; Antithrombin III; Intestinal Mucosa; Intestines; Lipid Peroxidation; Male; Malondialdehyde; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Time Factors

The protective effects of heat-shock protein (hsp) in rat small intestinal warm ischemia-reperfusion (I/R) injury are poorly understood.. Hsp-73 expression was induced in rat small intestine with use of sodium arsenite injected (6 mg/kg) through a catheter cannulated into the left common carotid artery 24 hours before ischemia (group 1). In the control group an equal volume of phosphate-buffered saline solution was injected (group 2). To block the induction of hsp-73 expression, sodium arsenate and quercetin (5 mg/kg) were injected (group 3).. The mean peak plasma levels of tumor necrosis factor-alpha and cytokine-induced neutrophil chemoattractant after reperfusion were lower in group 1 than in group 2. The tissue myeloperoxidase activity after reperfusion was lower in group 1 than in group 2. The mean peak plasma level of interleukin-10 after reperfusion was higher in group 1 than in group 2. The induction of hsp-73 expression reduced the synthesis of nitric oxide and the magnitude of the small intestinal warm I/R injury. The results in group 3 were similar to those in group 2.. Hsp-73 protects against small intestinal warm I/R injury by inhibiting the synthesis of inflammatory cytokines and the activation of neutrophils and by accelerating the synthesis of anti-inflammatory cytokines.

Topics: Animals; Arsenites; Blotting, Western; Chemokines, CXC; Chemotactic Factors; Dose-Response Relationship, Drug; Enzyme Inhibitors; Enzyme-Linked Immunosorbent Assay; Growth Inhibitors; Growth Substances; Heat-Shock Proteins; Hot Temperature; Intercellular Signaling Peptides and Proteins; Interleukin-10; Intestinal Mucosa; Intestine, Small; Male; Nitric Oxide; Peroxidase; Quercetin; Rats; Rats, Inbred Lew; Reperfusion Injury; Sodium Compounds; Tumor Necrosis Factor-alpha

We recently demonstrated that heat stress induction of heat shock protein 70 (HSP70) in donor animals before harvest decreases posttransplant ischemia-reperfusion injury in preserved rat lung isografts. The purpose of this study was to investigate the feasibility of HSP70 gene transfection into rat lung isografts using an adenoviral vector, and to study the effects of gene expression on subsequent ischemia-reperfusion injury.. In preliminary studies to determine the optimal titer, animals were injected with various titers of adenovirus-HSP70 (saline, 5 x 10(9), 1 x 10(10), and 2 x 10(10) plaque forming units [pfu]) and sacrificed 5 days after injection. To determine the optimal exposure time, animals were sacrificed at different times (0, 6, 24, and 72 hours) after intravenous injection of adenovirus-HSP70. In a subsequent series of transplant experiments, donors were allocated to three groups according to transfection strategy. Group 1 (n = 8) donors received 5 x 10(9) pfu adenovirus-HSP70 intravenously, group 2 (n = 7) donors received 5 x 10(9) pfu adenovirus-beta-galactosidase (as a virus control), and group 3 (n = 7) donors received saline and served as a negative control. Twenty-four hours after treatment all grafts were harvested and stored for 18 hours before orthotopic left lung transplantation. Twenty-four hours after implantation animals were sacrificed for assessment. The expression of HSP70 was assessed by Western blot analysis.. In preliminary studies, HSP70 was detectable even at low titers (5 x 10(9) pfu) of adenovirus-HSP70, and was detectable at low levels as early as 6 hours after intravenous administration. Heat shock protein 70 expression was maximal at 24 hours. In transplant experiments, Western blot analysis showed that overexpression of HSP70 occurred in the HSP70-transfected lungs. The mean arterial oxygenation 24 hours after reperfusion in group 1 was superior in comparison with other groups (p < 0.05). Wet to dry weight ratio (p < 0.05) and myeloperoxidase activity (p < 0.05) were also significantly less in group 1 grafts compared with the other groups.. This study demonstrates that in vivo, donor adenovirus-mediated gene transfer of HSP70 decreases subsequent ischemia-reperfusion injury in rat lung isografts.

Topics: Adenoviridae; Animals; Blotting, Western; Feasibility Studies; Gene Expression; Genetic Vectors; HSP70 Heat-Shock Proteins; HSP90 Heat-Shock Proteins; Lung Transplantation; Male; Peroxidase; Rats; Rats, Inbred F344; Reperfusion Injury; Transfection; Transplantation, Isogeneic

There is evidence that lung ischemia reperfusion injury is a result of the activation of components of the inflammatory cascade. However, the role of neutrophils in lung reperfusion injury continues to be a source of controversy.. Using an isolated, whole blood-perfused, ventilated rabbit lung model, we sought to characterize the pattern of reperfusion injury and investigate the contribution of neutrophils to this injury. Donor rabbits underwent lung harvest after pulmonary arterial prostaglandin E1 injection and Euro-Collins preservation solution flush. Group I lungs (n = 8) were immediately reperfused without ischemic storage. Group II lungs (n = 8) were stored for 18 h at 4 degrees C before reperfusion. Group III lungs (n = 10) underwent 18 h of ischemic storage and were reperfused with whole blood that was first passed through a leukocyte-depleting filter. All lungs were reperfused for 2 h.. Arterial oxygenation in group III progressively improved, and was significantly higher than that of group II after 2 h of reperfusion (272.58+/-58.97 vs 53.58+/-5.34 mm Hg, p = 0.01). Both pulmonary artery pressure and pulmonary vascular resistance were significantly reduced in group III when compared with group II (27.85+/-1.45 vs 44.15+/-4.77 mm Hg, p = 0.002; and 30,867+/-2,323 vs 52,775+/-6,386 dynes x sec x cm(-5), p = 0.003, respectively). Microvascular permeability in group III lungs was reduced to 73.98+/-6.15 compared with 117.16+/-12.78 ng Evans blue dye/g tissue in group II (p = 0.005). Group III myeloperoxidase activity was 56.92+/-6.31 deltaOD/g/min compared with 102.84+/-10.41 delta0d/g/min in group II (p = 0.002).. Leukocyte depletion of the blood reperfusate protects against microvascular permeability and significantly improves pulmonary graft function. The neutrophil plays a major role in amplifying lung injury later during reperfusion, and this lung ischemia reperfusion injury may be reversed through the interruption of the inflammatory cascade and the interference with neutrophil infiltration.

Topics: Animals; Disease Models, Animal; Female; In Vitro Techniques; Lung Transplantation; Male; Neutrophils; Peroxidase; Postoperative Complications; Rabbits; Reperfusion Injury

Trimetazidine (TMZ), a potent antioxidant agent, has been used to protect the myocardium, liver and kidney from ischemia reperfusion (IR) injury. We investigated the effect of TMZ, a cellular anti-ischemic agent and a free radical scavenger, on 60 min of warm intestinal IR injury in rats. Sprague-Dawley rats were divided into three groups: a sham-operated group (no IR injury, n = 8), an ischemic control group (control, n = 8), and a TMZ-treated group (3 mg/kg, n = 8). Malondialdehyde (MDA) levels, myeloperoxidase (MPO) activity, and mucosal damage were investigated after 120 min of reperfusion. MDA levels and MPO activity were more elevated and histopathological damage more severe in the control group than in the sham group (P < 0.05). MDA levels and MPO activity were lower and there was less histopathological damage in the TMZ group than in the control group (P < 0.05). Accumulation of lipid peroxidation products and neutrophils in mucosal tissues were significantly inhibited by TMZ treatment. We conclude that pretreatment of rats with TMZ before intestinal ischemia attenuates but does not prevent, histological damage.

Topics: Animals; Antioxidants; Free Radical Scavengers; Ileum; Intestinal Mucosa; Male; Malondialdehyde; Mesenteric Artery, Superior; Mesenteric Veins; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Time Factors; Trimetazidine

To find out whether plasma concentrations of protein carbonyl (a specific marker of oxidative damage of proteins) are increased during intestinal ischaemia-reperfusion and whether they are correlated with von Willebrand's factor (vWF, a marker of endothelial injury) or myeloperoxidase (a marker of neutrophil activation).. Randomised experimental study.. University department of surgery, New Zealand.. Thirty anaesthetised adult Wistar rats.. The sham operated group (n = 10) had laparotomy and isolation of the superior mesenteric artery without clamping. The ischaemia-reperfusion group (IR, n = 10) had the superior mesenteric artery clamped for 1 hour and reperfusion for 15 minutes. The control group (n = 10) had direct puncture of the heart to sample blood.. Plasma concentrations of protein carbonyl, vWF, and myeloperoxidase.. Plasma protein carbonyl concentrations were significantly higher in the IR group than in the sham group (p < 0.02, Mann-Whitney test, median (range) 0.187 (0.141-0.242) compared with 0.144 (0.121-0.185) nmol/mg) and in the control group (p < 0.01, Mann-Whitney test, median (range) 0.187 (0.141-0.242) compared with 0.136 (0.108-0.175) nmol/mg). There was a significant correlation between protein carbonyl and vWF concentrations (r = 0.54, F = 10.9, p < 0.003, linear regression) but not with those of myeloperoxidase.. Intestinal ischaemia-reperfusion caused an increase in the plasma protein carbonyl concentration, which is possibly produced by endothelial cells.

Topics: Animals; Blood Proteins; Intestine, Small; Male; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Time Factors; von Willebrand Factor

This study was designed to determine whether oxygen-derived free radicals play a role in the pathogenesis of gastric mucosal lesions produced by haemorrhagic shock and reperfusion experimental model in the rat. Ranitidine (H2-receptor blocker) in different doses, allopurinol, an inhibitor of xanthine oxidase and SOD (superoxide dysmutase) pre-treatment were used against haemorrhagic shock and reperfusion induced gastric mucosal lesions. Altogether 67 rats were divided into seven different groups. The area of gastric mucosal lesions was measured, the activity of endogenous peroxidase was examined histochemically and histological grading was made. Evans blue was used to demonstrate the improved permeability of gastric mucosal membranes. Ranitidine, in high dose, allopurinol and superoxide dysmutase significantly protected against haemorrhagic shock-induced gastric mucosal lesions, against improved membrane permeability and peroxidation.

Topics: Allopurinol; Animals; Free Radical Scavengers; Free Radicals; Gastric Mucosa; Histamine H2 Antagonists; Histocytochemistry; Male; Peroxidase; Ranitidine; Rats; Rats, Wistar; Reperfusion Injury; Shock; Shock, Hemorrhagic; Superoxide Dismutase; Xanthine Oxidase

to evaluate vitamin C supplementation in the prevention of ischaemia-reperfusion (I-R) induced acute lung injury.. Sprague-Dawley rats (n =6/group) were randomised into Control, I-R and I-R pretreated with vitamin C (3.3 g over 5 days). Ischaemia-reperfusion injury was induced by 30 minutes infrarenal aortic cross-clamping and 120 minutes reperfusion.. pulmonary microvascular injury was measured by broncho-alveolar lavage protein concentration, pulmonary neutrophil infiltration by tissue myeloperoxidase activity and bronchoalveolar lavage neutrophil counts. In a second experiment (n =5/group) neutrophil respiratory burst activity was measured in Control and vitamin C groups.. ischaemia-reperfusion resulted in a significant increase in both microvascular leakage and pulmonary neutrophil infiltration as measured by bronchoalveolar lavage protein concentration and pulmonary myeloperoxidase activity respectively. Pretreatment with vitamin C significantly attenuated both microvascular leakage and neutrophil infiltration. Neutrophil respiratory burst activity was significantly reduced in the vitamin C group (13.02 m.c.f.+/-0.3) compared with Control (19.04 m.c.f.+/-1. 9),p <0.02.. these data suggest that oral vitamin C therapy protects against ischaemia-reperfusion-induced acute lung injury, possibly by attenuating neutrophil respiratory burst activity.

Topics: Animals; Ascorbic Acid; Bronchoalveolar Lavage Fluid; Lung; Male; Microcirculation; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Respiratory Burst

The present study was designed to investigate the role of cardiac mast cells in the cardioprotective effect of norepinephrine-induced preconditioning. Isolated rat heart was subjected to 30 min of global ischemia followed by 30 min of reperfusion. Both ischemic and norepinephrine (100 microM) preconditioning markedly reduced ischemia-reperfusion-induced release of lactate dehydrogenose (LDH) in the coronary effluent and the incidence of ventricular premature beats (VPBs) and ventricular tachycardia/fibrillation (VT/VF) during the reperfusion phase. Ischemic and norepinephrine preconditioning also significantly reduced ischemia-reperfusion-induced release of mast cell peroxidase (MPO), a marker of mast cell degranulation. However, MPO release increased immediately after ischemic or norepinephrine preconditioning. Histological study with ruthenium red (0.005%) staining confirmed cardiac mast cell degranulation in ischemic and norepinephrine preconditioned isolated rat hearts. These findings tentatively suggest that pharmacological preconditioning with norepinephrine produces a cardioprotective and antiarrhythmic effect similar to ischemic preconditioning through degranulation of resident cardiac mast cells.

Topics: Animals; Arrhythmias, Cardiac; Cell Degranulation; Electrocardiography; Female; In Vitro Techniques; Ischemic Preconditioning, Myocardial; L-Lactate Dehydrogenase; Mast Cells; Myocardium; Norepinephrine; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Ruthenium Red; Ventricular Premature Complexes

Prolonged ischaemia followed by reperfusion (I/R) of skeletal muscle results in significant tissue injury. Ischaemic preconditioning (IPC), achieved by repeated brief periods of I/R before prolonged ischaemia or adenosine pretreatment, can prevent I/R injury in cardiac muscle. The aim of this study was to ascertain in a rodent model if damage to skeletal muscle due to global hindlimb tourniquet-induced I/R could be similarly attenuated.. Anaesthetized rats were randomized (n = 6-10 per group) to five groups: sham-operated controls; I/R (4 h of ischaemia, 2 h of reperfusion); IPC (three cycles of 10 min of ischaemia/10 min of reperfusion) alone; IPC immediately preceding I/R; or adenosine 1000 microg/kg immediately before I/R. At the end of reperfusion, biopsies were taken from the left gastrocnemius muscle for measurement of myeloperoxidase (MPO) and reduced glutathione (GSH). Before ischaemia and at the end of reperfusion, blood samples were taken for measurement of nitric oxide metabolites, tumour necrosis factor (TNF) alpha and macrophage inflammatory protein (MIP) 2.. IPC before I/R resulted in lower levels of MPO (P < 0.001) and TNF-alpha (P = 0.004), and higher levels of GSH (P < 0.001) and nitric oxide metabolites (P = 0.002) than I/R alone. Adenosine had effects comparable to IPC pretreatment (P < 0.001 for MPO, P = 0.002 for GSH, P = 0.02 for nitric oxide metabolites and P = 0.001 for TNF-alpha). There was no difference in the blood pressure or the MIP-2 concentration among the groups.. IPC or pretreatment with adenosine ameliorates the I/R injury of skeletal muscle.

Topics: Adenosine; Animals; Blood Pressure; Cardiovascular Agents; Chemokine CXCL2; Glutathione; Ischemic Preconditioning; Male; Monokines; Muscle, Skeletal; Nitric Oxide; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Tumor Necrosis Factor-alpha

Platelet activating factor (PAF) is an inflammatory mediator that participates in neutrophil activation and adhesion to the endothelial cells. The PAF-antagonist (L-659.989) improves survival in myocutaneous flaps after ischaemia-reperfusion injury. To establish whether PAF antagonism improves survival in a pure skin flap, we subjected bilateral porcine buttock skin flaps (n = 14) to eight hours of ischaemia and 18 hours of reperfusion. L-659.989 or saline were given by local intra-arterial bolus infusion five minutes before reperfusion. There was no improvement in flap survival. Neutrophil accumulation as indicated by myeloperoxidase activity was increased in both groups compared with control tissue that had not been operated on (p < 0.01). There was no difference between treatment groups. Although it protected myocutaneous flaps, PAF antagonism did not protect pure skin flaps from ischaemia-reperfusion injury. A possible explanation is differences in flow-patterns that do not allow otherwise effective drugs to enter the area at risk, and so inhibit them from exerting a beneficial effect.

Topics: Animals; Female; Furans; Neutrophil Activation; Peroxidase; Platelet Activating Factor; Reperfusion Injury; Surgical Flaps; Swine

Recent studies suggest that horses requiring surgical correction of strangulating intestinal obstruction may develop post operative complications as a result of ischaemia/reperfusion injury. Therefore, the mucosal and serosal margins of resected small intestine from 9 horses with small intestinal strangulating lesions were examined for evidence of ischaemia/reperfusion injury. Severe mucosal injury and marked elevations in myeloperoxidase activity were detected at ileal resection margins (n = 4), whereas the mucosa from proximal jejunal (n = 9) and distal jejunal (n = 5) resection margins was normal. However, the serosa from jejunal resection margins had evidence of haemorrhage and oedema, and the proximal jejunal serosa had significantly increased numbers of neutrophils. Histological injury in ileal stumps is indicative of the inability fully to resect the ileum in horses with distal small intestinal strangulations. One of 4 horses subjected to ileal resection was subjected to euthanasia and found to have a necrotic ileal stump. Evidence of serosal injury and neutrophil infiltration in the proximal jejunal resection margins may predispose horses to post operative adhesions. Four of 8 horses discharged from the hospital suffered from recurrent colic in the post operative period.

Topics: Anastomosis, Surgical; Animals; Follow-Up Studies; Horse Diseases; Horses; Intestinal Mucosa; Intestinal Obstruction; Intestine, Small; Lipid Peroxidation; Peroxidase; Reperfusion Injury

While necrosis is known as a major mechanism for the loss of viability of skeletal muscle following ischaemia and reperfusion, much less is known of the role of apoptosis. In this study rat hind limbs were subjected to 2 h of tourniquet ischaemia, then reperfused for either 0, 0.25, 0.5, 1, 3, 8, 16 or 24 h (n = 6 per group). Mean viability of muscle, assessed by tetrazolium dye reduction, after 2 h ischaemia and 24 h reperfusion was 17%. Histological examination revealed disrupted, necrotic muscle fibres from 30 min to 24 h reperfusion. Apoptotic nuclei were identified by haematoxylin staining and TUNEL, terminal deoxynucleotidyl transferase mediated dUTP nick end labelling. No TUNEL-positive cells were observed at the end of the ischaemic period, but a small number of TUNEL-positive endothelial and smooth muscle cells were found at 30 min reperfusion, with a progressive increase in their number up to 24 h reperfusion. Apoptotic neutrophils were detected after 8-24 h reperfusion. At no stage was apoptosis seen in the nuclei of skeletal muscle fibres. It appears that apoptosis plays no role in the death of muscle fibres after ischaemia-reperfusion injury to skeletal muscle.

Topics: Animals; Apoptosis; Female; Glutathione; In Situ Nick-End Labeling; Male; Muscle, Skeletal; Necrosis; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

The effects of recombinant soluble P-selectin glycoprotein ligand-1 (rsPSGL.Ig) were studied after 120 min of splanchnic artery occlusion and 120 min of reperfusion (SAO/R). SAO/R rats administered a low-affinity mutant form of rsPSGL.Ig exhibited signs of severe circulatory collapse with marked hypotension, a survival time of only 37+/-16 min, and significant increases in intestinal myeloperoxidase (MPO) activity (P<0.01). In addition, SAO/R rats given rsPSGL.Ig low-affinity mutant showed severe endothelial dysfunction characterized by a blunted vasorelaxation to the endothelium-dependent vasodilator acetylcholine in comparison to sham-operated controls (30+/-9% vs. 97+/-3%). Administration of rsPSGL.Ig (0.5 mg/kg) significantly improved mean arterial blood pressure and increased survival time to 107+/-13 min (P <0.01). rsPSGL.Ig treatment also resulted in a significant attenuation in both intestinal MPO activity as well as the SAO/R-induced decline in endothelium-dependent vasorelaxation of superior mesenteric artery rings (P<0.01). In addition, rsPSGL.Ig attenuated in vitro neutrophil adherence to thrombin-stimulated superior mesenteric artery endothelium to a comparable degree as a P-selectin monoclonal antibody. These data suggest that rsPSGL.Ig provides beneficial effects by preserving endothelial function and attenuating neutrophil-endothelial cell interactions in the splanchnic circulation following ischemia-reperfusion.

Topics: Acute Disease; Animals; Blood Pressure; Cell Adhesion; In Vitro Techniques; Intestines; Ligands; Male; Membrane Glycoproteins; P-Selectin; Peroxidase; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Reperfusion Injury; Solubility; Splanchnic Circulation; Survival Rate

Ischemia/reperfusion injury is a commonly occurring event with severe pathologic consequences. Reperfusion initiates both the local and systematic damage in part through rapid oxygen generation. The glutathione system is a major mechanism of reducing this oxidative stress. If this system can be maintained or augmented during this stress then less damage may occur. Glutamine provides the source of glutamate to this system and has been shown to preserve total glutathione levels after injury/ischemia to both hepatic and gut models. To test this effect, we looked at glutamine and its role in ischemia/reperfusion injury in a rat hind limb model.. Fifty male HSD/Holtzman rats weighing 350-400 g were randomized to receive glutamine (3% sol) or normal saline via intraperitoneal injections. The groups were then subjected to 2 hours of ischemia to their hind limbs using the Tourni-Cot method. Animals were then randomized to reperfusion groups of 30 minutes, 2 hours, and 4 hours. Muscle tissue assays were performed for lipid peroxidation (LPO), total glutathione (GSH), and myeloperoxidase (MPO). Peripheral blood was analyzed for creatinephosphokinase levels (CPK).. Animals that received glutamine showed a general trend of less lipid peroxidation products than the normal saline groups. In animals that received glutamine and underwent 2 hours of ischemia and reperfusion times of 0 minutes, 30 minutes, and 2 hours, there were significantly less percent changes in lipid peroxidation products from controls (4.6% vs 48.2%, P <0.05), (18.9% vs 123%, P <0.05), (12.6% vs 115%, P <0.05). A general trend upward was noted in CPK levels in both groups. In animals receiving 2 hours of ischemia and 30 minutes of reperfusion, there was a significantly greater level of creatinephosphokinase (CPK) calculated as percent change from control in the normal saline group as compared with the glutamine group (209.2% vs 92.7%). Myeloperoxidase assay of muscle tissue revealed a progressive increase as the reperfusion times grew. In animals receiving 2 hours of ischemia and 30 minutes of reperfusion, the normal saline group had a significantly larger percent increase from controls than the group that received glutamine (1126.4% vs 108%, P <0.05). Also, in those animals receiving 4 hours of reperfusion, the normal saline group had a significantly higher percent increase in MPO content than the glutamine group (6245% vs 108%, P <0.05). Total glutathione levels decreased rapidly as reperfusion occurred in both the normal saline and glutamine groups. No significant difference between the groups was noted.. Total glutathione levels during reperfusion were not significantly different in the groups receiving glutamine versus normal saline. Glutamine may provide an initial protective effect on reperfusion injury after moderate reperfusion times in the hind limb model as defined by CPK and LPO levels. Glutamine may blunt neutrophil recruitment after longer reperfusion times (4 hours) in the ischemic hind limb. Total glutathione levels decreased significantly after moderate levels of ischemia (2 hours) and reperfusion (30 minutes, 2 hours).

Topics: Animals; Creatine Kinase; Disease Models, Animal; Glutamic Acid; Glutamine; Glutathione; Hindlimb; Injections, Intraperitoneal; Ischemia; Lipid Peroxidation; Male; Muscle, Skeletal; Neutrophils; Oxidative Stress; Peroxidase; Protective Agents; Random Allocation; Rats; Rats, Inbred Strains; Reperfusion Injury; Single-Blind Method; Time Factors

Ischemia followed by reperfusion leads to severe organ injury and dysfunction. Inflammation is considered to be the most important cause of tissue injury in organs subjected to ischemia. The mechanism that triggers inflammation and organ injury after ischemia remains to be elucidated, although different causes have been postulated. We investigated the role of apoptosis in the induction of inflammation and organ damage after renal ischemia. Using a murine model, we demonstrate a relationship between apoptosis and subsequent inflammation. At the time of reperfusion, administration of the antiapoptotic agents IGF-1 and ZVAD-fmk (a caspase inactivator) prevented the early onset of not only renal apoptosis, but also inflammation and tissue injury. Conversely, when the antiapoptotic agents were administered after onset of apoptosis, these protective effects were completely abrogated. The presence of apoptosis was directly correlated with posttranslational processing of the endothelial monocyte-activating polypeptide II (EMAP-II), which may explain apoptosis-induced influx and sequestration of leukocytes in the reperfused kidney. These results strongly suggest that apoptosis is a crucial event that can initiate reperfusion-induced inflammation and subsequent tissue injury. The newly described pathophysiological insights provide important opportunities to effectively prevent clinical manifestations of reperfusion injury in the kidney, and potentially in other organs.

Topics: Amino Acid Chloromethyl Ketones; Animals; Apoptosis; Blood Urea Nitrogen; Caspases; Chemotaxis, Leukocyte; Cysteine Proteinase Inhibitors; Cytokines; Depression, Chemical; Drug Administration Schedule; Epidermal Growth Factor; Humans; In Situ Nick-End Labeling; Insulin-Like Growth Factor I; Ischemia; Kidney; Male; Mice; Neoplasm Proteins; Nephritis; Peroxidase; Protein Processing, Post-Translational; Recombinant Proteins; Reperfusion Injury; RNA-Binding Proteins

We used IL-6 knock-out (KO) mice to evaluate a possible role for IL-6 in the pathogenesis of splanchnic artery occlusion shock (SAO). SAO shock was induced by clamping both the superior mesenteric artery and the celiac trunk, followed by release of the clamp. There was a marked increase in the peroxynitrite formation in the plasma of the SAO-shocked IL-6 wild-type (WT) mice after reperfusion. Immunohistochemical examination demonstrated a marked increase in the immunoreactivity to nitrotyrosine in the necrotic ileum in shocked IL-6 WT mice. SAO-shocked WT mice developed a significant increase of tissue myeloperoxidase (MPO) and malondialdehyde (MDA) activity and marked histological injury to the distal ileum. SAO shock was also associated with a significant mortality (0% survival). Reperfused ileum tissue sections from SAO-shocked WT mice showed positive staining for P-selectin. Little specific staining was observed in sham-WT mice. Staining of ileum tissue obtained from sham-operated WT mice with anti-ICAM-1 antibody showed weak but diffuse staining, demonstrating that ICAM-1 is constitutively expressed. However, after SAO shock the staining intensity increased substantially in the ileum section from WT mice. Intensity and degree of P-selectin and ICAM-1 were markedly reduced in tissue section from SAO-shocked IL-6 KO mice. SAO-shocked IL-6 KO mice also show significant reduction of neutrophil infiltration into the reperfused intestine, as evidenced by reduced MPO activity, improved histological status of the reperfused tissues, reduced peroxynitrite formation, reduced MDA levels, and improved survival. In vivo treatment with anti-IL-6 significantly prevents the inflammatory process. Our results clearly demonstrate that IL-6 plays an important role in ischemia and reperfusion injury and allows the hypothesis that inhibition of IL-6 may represent a novel and possible strategy. Part of this effect may be due to inhibition of the expression of adhesion molecules and subsequent reduction of neutrophil-mediated cellular injury.

Topics: Animals; Antibodies, Monoclonal; Arterial Occlusive Diseases; Celiac Artery; Constriction; Cytokines; Ileum; Immunity, Innate; Intercellular Adhesion Molecule-1; Interleukin-6; Ischemia; Leukocyte Count; Lipid Peroxidation; Malondialdehyde; Mesenteric Artery, Superior; Mice; Mice, Knockout; Neutrophils; Nitrates; Nitric Oxide; P-Selectin; Peroxidase; Reperfusion Injury; Shock; Splanchnic Circulation; Tyrosine

Topics: Acetylcysteine; Adenosine Triphosphate; Allopurinol; Animals; Glutathione; Heart; Intestine, Small; Ischemia; Liver; Lung; Malondialdehyde; Mesenteric Arteries; Multiple Organ Failure; Myocardium; Oxidative Stress; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Somatostatin

Topics: Adenosine Triphosphate; Animals; Glutathione; Intestine, Small; Ischemia; Malondialdehyde; Mesenteric Artery, Superior; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Somatostatin

Hepatic ischemia/reperfusion injury is initiated by the activation of Kupffer cells and their subsequent release of proinflammatory mediators, including tumor necrosis factor-alpha (TNFalpha). These mediators stimulate a cascade of events including up-regulation of CXC chemokines and vascular endothelial adhesion molecules, leading to hepatic neutrophil recruitment and tissue injury. Interleukin-13 (IL-13) is a cytokine that has been shown to suppress macrophage production of proinflammatory mediators. The objective of the current study was to determine whether IL-13 could regulate the liver inflammatory injury induced by ischemia and reperfusion. C57BL/6 mice underwent 90 minutes of partial hepatic ischemia followed by reperfusion with or without intravenous administration of recombinant murine IL-13. Hepatic ischemia/reperfusion increased expression of TNFalpha and macrophage inflammatory protein-2 (MIP-2), leading to hepatic neutrophil recruitment, hepatocellular injury, and liver edema. Administration of IL-13 reduced the production of TNFalpha and MIP-2 mRNA and protein. IL-13 suppressed liver neutrophil recruitment by up to 72% and hepatocellular injury and liver edema were each reduced by >60%. Administration of IL-13 had no effect on liver NFkappaB activation, but greatly increased the activation of STAT6. The data suggest that the hepatoprotective effects of IL-13 may be a result of STAT6 activation.

Topics: Animals; Chemokine CXCL2; Interleukin-13; Liver; Male; Mice; Mice, Inbred C57BL; Monokines; Neutrophils; NF-kappa B; Peroxidase; Recombinant Proteins; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; STAT6 Transcription Factor; Time Factors; Trans-Activators; Tumor Necrosis Factor-alpha

Platelet-activating factor (PAF), cytokines, proteases, and other factors are probably involved in the development of gut barrier dysfunction following intestinal ischemia and reperfusion (I/R), although the act underlying pathophysiological mechanisms has not yet been fully clarified. The aim of the present study was to clarify the relationship of intestinal barrier integrity to systemic levels of interleukin-1beta, interleukin-6, and protease inhibitor levels and local leukocyte accumulation in a rat model of intestinal ischemia for 40 min followed by 3 or 12 h reperfusion, with or without treatment with a PAF inhibitor.. Myeloperoxidase (MPO) content in the small intestinal mucosa, serum levels of interleukin-1beta and -6, and plasma protease inhibitors, and intestinal endothelial and epithelial permeability were assessed, with or without treatment with the PAF antagonist lexipafant.. Intestinal I/R resulted in intestinal barrier dysfunction with pronounced plasma leakage to the intestinal lumen, the leakage being aggravated following a longer reperfusion period. Proteolytic plasma activity was evident by low levels of the plasma protease inhibitors measured. MPO content increased significantly after I/R, as did serum levels of interleukin-1beta and -6, without difference between the two periods of reperfusion. Treatment with the PAF inhibitor lexipafant partly, though not fully, restored the changes caused by I/R.. PAF seems to be involved in the release of cytokines, such as interleukin-1 and -6, consumption of protease inhibitors, and impaired intestinal barrier integrity seen following intestinal I/R. Treatment with a PAF antagonist was effective in restoring the changes caused by intestinal I/R, though not reaching complete normal levels.

Topics: Animals; Interleukin-1; Interleukin-6; Intestinal Mucosa; Intestines; Ischemia; Male; Mesenteric Arteries; Permeability; Peroxidase; Platelet Activating Factor; Protease Inhibitors; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Ischemia-reperfusion injury, a common source of renal dysfunction in adults, is associated with tubular epithelial cell damage. Since fibroblast growth factors (FGF) attenuated tissue injury after transient myocardial ischemia, we hypothesized that acidic fibroblast growth factor (aFGF; FGF-1) would attenuate renal ischemia-reperfusion injury. We studied the effects of FGF-1 in a rat model of acute renal failure induced by bilateral renal ischemia (60 min) and 1, 2 or 7 days reperfusion. After FGF-1 administration at the onset of renal reperfusion, there was less functional impairment of the kidneys. The histological changes were not as severe as in controls. Increases in serum creatinine and blood urea nitrogen 24 h after reperfusion were attenuated by 35% (p< 0.01) and by 53% (p< 0.001), respectively, in FGF-1-treated animals compared to vehicle-treated rats. The ischemia/reperfusion-induced increase in tissue myeloperoxidase, a marker of neutrophil infiltration, was mitigated (67% reduction, p< 0.05) with FGF-1 treatment. As shown by histology, neutrophil infiltration and tubular cell necrosis in medulla were less pronounced (p< 0.0001 and p< 0.05, respectively) in animals receiving FGF-1. Furthermore, ischemia-induced apoptosis, prevalent in tubular cells of the cortex, was also attenuated by FGF-1-treatment (83% reduction, p< 0.0001). Pretreatment of animals with Nw-nitro-L-arginine (L-NNA), an inhibitor of nitric oxide synthase, abolished the attenuating effects of FGF-1 on neutrophil infiltration, suggesting that nitric oxide might participate in the anti-inflammatory effects of FGF-1 in this experimental design. Our data support a role for FGF-1 in attenuation of renal damage or failure after ischemia-reperfusion injury of the kidney, in part at least by inhibition of neutrophil infiltration.

Topics: Animals; Apoptosis; Fibroblast Growth Factor 1; Fibroblast Growth Factor 2; Ischemia; Kidney; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury

Pathophysiologic changes of posttransplant lung ischemia/reperfusion injury are mediated by redundant cellular and humoral mechanisms. We investigated the protective effect of combined administration of platelet activating factor (PAF) and endothelin (ET) antagonists after prolonged ischemia in a small animal lung transplantation model.. Orthotopic left lung transplantation was performed after 20 hours cold ischemia in male Fischer (F344) rats weighing 200-250 g. Group I served as control. In Group II, donors received 1 mg/kg body weight of the endothelin antagonist TAK-044, and recipients 2 mg/kg. Group III was treated with the PAF antagonist TCV-309 (donor: 50 microg/kg; recipient: 100 microg/kg) (Takeda Chemicals Ltd.). Group IV received a combined treatment with both substances at the same dosage. Twenty-four hours after reperfusion, the native contralateral lung was occluded to assess gas exchange of the graft only, and 5 minutes later the thoracic aorta was punctured for arterial blood gas analysis (n = 5). In other animals (n = 5), lung tissue was frozen 24 hours after reperfusion and assessed for myeloperoxidase activity (MPO) and thiobarbituric acid reactive substances.. Combined inhibition of PAF and ET-1 at the receptor level resulted in significantly improved graft function as compared to controls (Group I), and to groups treated with either TAK-044 or TCV-309. This was determined by a higher arterial oxygen content (112 +/- 9 mmHg, p = .00061 vs control, 48 +/- 5 mmHg), reduced MPO activity (0.35 +/- 0.02 deltaOD/mg/min, p = .000002 vs control, 1.1 +/- 0.1 deltaOD/mg/min) and reduced lipid peroxidation (59.5 +/- 2.5 pmol/g, p = .011 vs control, 78.5 +/- 4.1 pmol/g). The improvement of arterial oxygen (Group II 77 +/- 10 mmHg, p = .027 vs control; Group III 84 +/- 8 mmHg, p = .0081 vs control) and reduction of MPO activity (Group II 0.85 +/- 0.061 deltaOD/mg/min, p = .017; Group III 0.92 +/- 0.079 deltaOD/mg/min, p = .058) in groups treated with either a PAF antagonist or an ET antagonist was significantly less than in Group IV.. Combined donor and recipient treatment with an ET antagonist and a PAF antagonist results in superior posttransplant graft function 24 hours after reperfusion, suggesting a synergistic role of ET-1 and PAF in the mediation of reperfusion injury in this model. Single treatment with either of the antagonists revealed only a slight improvement compared to untreated controls.

Topics: Animals; Drug Therapy, Combination; Endothelin Receptor Antagonists; Isoquinolines; Lipid Peroxidation; Lung; Lung Transplantation; Male; Oxygen; Peptides, Cyclic; Peroxidase; Platelet Activating Factor; Pyridinium Compounds; Rats; Rats, Inbred F344; Reperfusion Injury; Tetrahydroisoquinolines; Thiobarbituric Acid Reactive Substances

Substitution of the nitric oxide (NO) pathway reduces ischemia/reperfusion injury after lung transplantation. 8-Br-cGMP is a membrane-permeable analogue of cGMP, the second messenger of NO. In this study, we evaluated the effect of administration of 8-Br-cGMP in the flush solution on early graft function.. Unilateral left lung transplantation was performed in 10 weight-matched pairs of outbred pigs (24 to 31 kg). Donor lungs were flushed with 1.5 L cold (1 degree C) low potassium dextrane (LPD) solution and preserved for 20 hours. In group I (n = 5), 8-Br-cGMP (1 mg/kg) was added to the flush solution. In group II (n = 5), 8 microg/kg prostaglandin E1 (PGE1) was injected into the pulmonary artery (PA) before flush. One hour after reperfusion, the recipients' contralateral right PA and bronchus were ligated to assess graft function only. cGMP levels in the PA and pulmonary vein were measured. Extravascular lung water index (EVLWI), pulmonary vascular resistance, mean PA pressure, and gas exchange (PaO2) were assessed during a 5-hour observation period. Lipid peroxidation (thiobarbituric acid-reactive substance) and neutrophil migration to the allograft (myeloperoxidase activity) were measured at the end of the assessment.. In group I, a significant reduction of EVLWI (group I, 6.7 +/- 1.0 mL/kg vs group II, 10.1 +/- 0.6 ml/kg after 2 hours of reperfusion; p = 0.022), TBARS (group I, 65.6 +/- 10.0 pmol/g vs group II, 120.8 +/- 7.2 pmol/g, p = 0.0039), and MPO activity (group I, 0.8 +/- 0.1 change in optical density, (deltaOD)/mg/min vs group II, 1.7 +/- 0.3 deltaOD/mg/min, p = 0.036) was noted in comparison with group II. PaO2 levels tended to be higher in cGMP-treated animals, but the changes were not significant. Hemodynamic parameters did not differ between groups.. In this large animal model of lung allograft ischemia/reperfusion injury, 8-Br-cGMP as additive to the flush solution improves posttransplant lung edema, lipid peroxidation, and neutrophil migration to the allograft. This effect is not attributable to improved flush by vasodilation, as we compared 8-Br-cGMP with PGE1 given before flush in control animals.

Topics: Alprostadil; Animals; Cyclic GMP; Hemodynamics; Lung; Lung Transplantation; Neutrophils; Organ Preservation; Organ Preservation Solutions; Peroxidase; Pulmonary Gas Exchange; Reperfusion Injury; Swine; Vascular Resistance

The objective of this study was to investigate the effects of the micronized purified flavonoid fraction Daflon 500 mg (90% diosmin and 10% hesperidin) on I/R-induced microvascular leukocyte-endothelium interaction and leakage of the high molecular weight plasma tracer FITC-dextran (relative molecular mass, 150 kd) as assessed in the striated skin muscle of the dorsal skin fold chamber model in the hamster. Intravital fluorescence microscopy was used for analysis of microvascular perfusion, leukocyte-endothelium interaction, and macromolecular leakage of FITC-dextran 150 kd in the striated skin muscle of the hamster. A tourniquet ischemia of 4 hours' duration was induced followed by reperfusion. Animals were treated with an oral administration of Daflon 500 mg (n = six) or its vehicle (5% Arabic gum solution, n = six) for 8 days at a daily dose of 30 mg/kg body weight. Measurements in the microcirculation were made before the 8-day feeding protocol before induction of ischemia and at 0.5, 2, and 24 hours of reperfusion. In the absence of I/R, no differences in microvascular perfusion, leukocyte-endothelium interaction, and macromolecular leakage were found in Daflon 500 mg and vehicle-treated control animals before and after administration of the drugs. Induction of ischemia and reperfusion, however, elicited a significant increase in venular leukocyte rolling and sticking in vehicle-treated animals, which was accompanied by enhancement of leakage of FITC-dextran 150 kd into the perivascular tissue. Treatment with Daflon 500 mg had no effect on postischemic leukocyte rolling and sticking, and macromolecular leakage of FITC-dextran 150 kd from arterioles and postcapillary venules was significantly reduced. These data indicate that Daflon 500 mg preserves the endothelial barrier function of striated skin muscle arterioles and venules after I/R, which appears to be independent of an action on postischemic intravascular leukocyte rolling and sticking.

Topics: Animals; Cell Adhesion; Cricetinae; Diosmin; Disease Models, Animal; Endothelium, Vascular; Ischemia; Leukocytes; Male; Mesocricetus; Microcirculation; Muscle, Skeletal; Peroxidase; Reperfusion Injury; Skin

The adenosine-A2A receptor on the neutrophil is responsible for several anti-inflammatory actions. We hypothesized that DWH-146e, a selective adenosine-A2A agonist, would reduce lung reperfusion injury following transplantation.. We used an isolated, whole blood-perfused, ventilated rabbit lung model. Donor rabbits underwent lung harvest after pulmonary arterial PGE1 injection and Euro-Collins preservation solution flush, and lungs were preserved for 18 hours at 4 degrees C. Group I lungs (n = 9) served as control subjects. Group II lungs (n = 9) were reperfused with whole blood that was first passed through a leukocyte-depleting filter. In group III (n = 9), DWH-146e was added to the blood reperfusate (25 microg/kg) immediately before reperfusion and was administered throughout the reperfusion period (1 microg/kg/min). All lungs were reperfused for 30 minutes.. Arterial oxygenation in group II and group III was significantly higher than that of group I after 30 minutes of reperfusion (514.27 +/- 35.80 and 461.12 +/- 43.77 vs 91.41 +/- 20.58 mm Hg, p < .001). Pulmonary vascular resistance was significantly reduced in group III (22,783 +/- 357 dynes x s x cm(-5)) compared to both group II and group I (31,057 +/- 1743 and 36,911 +/- 2173 dynes x s x cm(-5), p < .001). Airway compliance was improved in groups II and III when compared to group I (1.68 +/- 0.08 and 1.68 +/- 0.05 vs 1.36 +/- 0.13, p = .03). Microvascular permeability in group III was reduced to 106.82 +/- 17.09 compared with 165.70 +/- 21.83 ng Evans blue dye per gram of tissue in group I (p = .05). Group III myeloperoxidase activity was 39.88 +/- 4.87 compared with 88.70 +/- 18.69 deltaOD/g/min in group I (p = .03); group II myeloperoxidase activity was 56.06 +/- 7.46.. DWH-146e reduced lung neutrophil sequestration and dramatically improved pulmonary graft function. Neutrophils are important components of the inflammatory cascade of reperfusion injury and their source may include both the circulating blood and the lung graft itself. Selective adenosine-A2A activation interrupts the neutrophil-mediated inflammatory response and reduces lung reperfusion injury following transplantation.

Topics: Adenosine; Analysis of Variance; Animals; Female; Lung; Lung Transplantation; Male; Neutrophils; Peroxidase; Purinergic P1 Receptor Agonists; Rabbits; Random Allocation; Receptors, Purinergic P1; Reperfusion; Reperfusion Injury; Tissue and Organ Harvesting

Hepatic ischemia and reperfusion cause local and remote organ injury. This injury culminates from an integrated cascade of proinflammatory cytokines, chemokines, and adhesion molecules, many of which are regulated by the transcription factor nuclear factor-kappaB (NF-kappaB). The anti-inflammatory cytokine interleukin-10 (IL-10) has been shown to have inhibitory effects on NF-kappaB. The objective of the current study was to determine whether IL-10 could suppress pulmonary NF-kappaB activation and ensuing lung injury induced by hepatic ischemia-reperfusion. C57BL/6 mice underwent partial hepatic ischemia with or without intravenous administration of IL-10. Hepatic ischemia-reperfusion resulted in pulmonary NF-kappaB activation, increased mRNA expression of tumor necrosis factor-alpha (TNF-alpha), and macrophage inflammatory protein-2 (MIP-2), as well as increased pulmonary neutrophil accumulation and lung edema. Administration of IL-10 suppressed lung NF-kappaB activation, reduced TNF-alpha and MIP-2 mRNA expression, and decreased pulmonary neutrophil recruitment and lung injury. The data suggest that IL-10 protects against hepatic ischemia and reperfusion-induced lung injury by inhibiting lung NF-kappaB activation and the resulting pulmonary production of proinflammatory mediators.

Topics: Animals; Chemokine CXCL2; Gene Expression; Hepatopulmonary Syndrome; Interleukin-10; Liver; Liver Diseases; Male; Mice; Mice, Inbred C57BL; Monokines; Neutrophils; NF-kappa B; Peroxidase; Pneumonia; Pulmonary Edema; Reperfusion Injury; RNA, Messenger; Tumor Necrosis Factor-alpha

This study evaluates whether preconditioning could modulate the injurious effects of tumor necrosis factor (TNF) on liver and lung following hepatic ischemia-reperfusion (I/R) by inhibiting hepatic postischemic TNF release. The inhibition of hepatic TNF release from Kupffer cells with gadolinium chloride (GdCl(3)) previous to ischemia maintained TNF at control levels, attenuating the increases in transaminases, vascular permeability, and edema associated with hepatic I/R injury. TNF addition reverted this beneficial effect, indicating the implication of the TNF released mainly from Kupffer cells in hepatic I/R injury. Preconditioning prevented hepatic TNF increases, thus attenuating the liver injury, while TNF addition abolished the benefits of preconditioning. Inhibition of nitric oxide (NO) synthesis abolished the effect of preconditioning, whereas GdCl(3) addition avoided the injurious effect of NO inhibition. In addition, NO administration before I/R offered similar results to those found in preconditioning, while TNF addition abolished the benefits of NO. Thus, the effect of preconditioning on TNF release after hepatic I/R is mediated by NO. Inhibition of hepatic TNF release from Kupffer cells with GdCl(3) prevented both the increase in plasma TNF and the injurious effect in lung seen after hepatic I/R, and these effects were reverted with TNF addition. Preconditioning resulting in reduced hepatic TNF levels prevented the systemic TNF release, thus reducing the lung damage following hepatic I/R. However, TNF addition abolished the protective effect of preconditioning on lung injury. These findings indicate that preconditioning attenuates hepatic postischemic TNF release from Kupffer cells, thus probably reducing the liver and lung injury following hepatic I/R, and that this effect of preconditioning is mediated by NO.

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Capillary Permeability; Edema; Enzyme Inhibitors; Gadolinium; Ischemic Preconditioning; Kupffer Cells; Liver; Lung; Male; Necrosis; Neutrophil Infiltration; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Donors; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Tumor Necrosis Factor-alpha

To assess the effects of gabexate mesilate (FOY), a protease inhibitor, on a canine model of pulmonary ischemia-reperfusion injury. FOY has been applied clinically to treat acute pancreatitis and disseminated intravascular coagulation (DIC) and has been found to suppress some leukocyte-mediated tissue injuries in both in vitro and in vivo studies.. Comparison of four experimental groups: group 1 (untreated control, n = 8), unilateral (left) pulmonary ischemia due to perfusion and ventilation obstruction followed by reperfusion, without receiving any specific treatment; group 2 (negative control, sham operation, n = 8), left pulmonary hilar dissection without ischemia; group 3 (FOY posttreatment, n = 8), FOY treatment during the reperfusion stage only; and group 4 (FOY pretreatment, n = 8), FOY treatment before ischemia and then continued during reperfusion.. University animal laboratory.. Heart-worm-free mongrel dogs (12 to 15 kg body wt) were anesthetized with pentobarbital and mechanically ventilated.. Lung ischemia was made by snaring the left pulmonary artery and veins and clamping the bronchus with peribronchial tissue for 90 min followed by reperfusion for 18 h. Animals of the two treatment groups received a 1 mg/kg bolus of FOY at the beginning of reperfusion, with infusion of 2 mg/kg/h of FOY continuously starting 30 min before ischemia (group 4) or after reperfusion (group 3). During this study the following were measured: hemodynamics and aerodynamics, blood gas, bronchoalveolar lavage (BAL) fluid neutrophil percentage and protein concentration, lung wet to dry weight ratio (W/D ratio), myeloperoxidase (MPO) activity of the lung tissue, alveolar neutrophil infiltration, and degree of injury.. This model of lung ischemia-reperfusion induced significant pulmonary hypertension, increased pulmonary vascular resistance, decreased pulmonary dynamic compliance and arterial hypoxemia, increased BAL fluid total protein amount and neutrophil percentage, and increased alveolar neutrophil infiltration, histological injury score, and lung tissue MPO assay (group 1). Animals of the sham operation (negative control, group 2) showed only minimal changes in the above parameters. Treatment with FOY significantly attenuated the injury by decreasing the lung W/D ratio, alveolar neutrophil infiltration, histological injury score, lung tissue MPO assay, BAL fluid neutrophil percentage, and protein amount. Pretreatment with FOY (group 4) attenuated the injury to a significantly greater degree than it did when administered at the reperfusion stage only (group 3), which was reflected by the above-mentioned parameters, and as well significantly improved gas exchange function. FOY treatment was found to have little effect in altering hemodynamics and aerodynamics at most time points in this model of lung injury.. FOY can attenuate the ischemia-reperfusion-induced acute lung injury in dogs by ameliorating the degree of alveolar membrane permeability change, neutrophil aggregation, and activation. FOY treatment starting before ischemia attenuated this injury to a significantly higher degree than its use after ischemia. However, the effect of FOY may be partial because it cannot alter the hemodynamics or aerodynamics as prominently as other parameters in this type of lung injury. Concomitant use of FOY with other agents will have additive or synergic effects in preventing lung ischemia-reperfusion injury.

Topics: Animals; Bronchoalveolar Lavage Fluid; Dogs; Gabexate; Hemodynamics; Ischemia; Lung; Neutrophils; Peroxidase; Reperfusion Injury; Respiratory Distress Syndrome; Serine Proteinase Inhibitors

The effect of pretreatment with FTY720 (2-amino-2-[2-(4-octylphenyl)ethyl]-1,3-propanediol hydrochloride) or cyclosporin, or both, on neutrophil-mediated injury has been examined by use of a rat model of transient clamping of hepatic flow. Pretreatment with FTY720 alone or with cyclosporin induced a marked reduction of circulatory lymphocytes, whereas the use of these drugs in combination was very effective at suppressing the elevation of the number of peripheral polymorphonuclear neutrophils (PMN) after reperfusion. Pretreatment with cyclosporin, with or without FTY720, significantly reduced hepatic damage, whereas FTY720 alone tended to prolong hepatic damage. Pretreatment of cyclosporin alone, but not in combination with FTY720, significantly reduced the accumulation of PMN and led to lower myeloperoxidase levels in the damaged liver. In conclusion, pretreatment with cyclosporin, with or without FTY720, reduced hepatic damage after warm ischaemia-reperfusion, whereas pretreatment with FTY720 alone tended to prolong this damage.

Topics: Animals; Cyclosporine; Fingolimod Hydrochloride; Immunosuppressive Agents; Leukocyte Count; Leukocytes, Mononuclear; Liver; Male; Neutrophil Activation; Peroxidase; Propylene Glycols; Rats; Rats, Wistar; Reperfusion Injury; Sphingosine; Transaminases; Tumor Necrosis Factor-alpha

1 Reactive oxygen species have been demonstrated to play a critical role in post-ischaemic tissue injury. The present experiment was designed to evaluate the effects of SB 211475, a hydroxylated metabolite of the new beta-adrenoceptor antagonist, carvedilol, on rat splanchnic ischaemia (SI, 60 min) and reperfusion(R)-induced shock and tissue injury. 2 Administration of SB 211475 two min before R attenuated SI/R injury in a dose-dependent manner. At doses of 0.5 mg kg(-1) and 1.0 mg kg(-1), SB 211475 exerted significant anti-shock and endothelial protective effects, characterized by prolonged survival times, increased survival rates, attenuated increases in tissue myeloperoxidase activity and haematocrits, and preserved endothelium-dependent vasorelaxation. 3 Administration of 1 mg kg(-1) carvedilol attenuated shock-induced tissue injury and endothelial dysfunction. However, administration of 0.5 mg kg(-1) carvedilol had no protective effects on post-ischaemic tissue injury. 4 Previous studies have shown that SB 211475 has virtually no beta-blocking activity but possesses more potent antioxidant activity than carvedilol. In the present study, SB 211475 exerted more potent protective effects than the parent compound, suggesting that this metabolite of carvedilol is superior to carvedilol with regard to its protection against post-ischaemia tissue injury.

Topics: Adrenergic beta-Antagonists; Animals; Antioxidants; Blood Pressure; Carbazoles; Carvedilol; Endothelium, Vascular; In Vitro Techniques; Ischemia; Male; Mesenteric Artery, Superior; Muscle Relaxation; Muscle, Smooth, Vascular; Peroxidase; Propanolamines; Rats; Rats, Sprague-Dawley; Reperfusion Injury

The purpose of this study was to determine whether depletion of circulating neutrophils, using an antineutrophil monoclonal antibody (RP3), would attenuate ischemia/reperfusion injury in rat skeletal muscle. A 3- and 5-hr period of ischemia was induced unilaterally into the hindlimbs of rats; the isolated limbs were then reperfused for 24 hr after ischemia. The gastrocnemius muscle was then removed, and blood was taken simultaneously. The hematologic parameters were measured, muscle neutrophil sequestration was assessed by myeloperoxidase (MPO) activity, free radical production was evaluated by the tissue lipid peroxides (LPO) levels, muscle viability was assessed by tissue levels of adenosine triphosphate (ATP) and creatine phosphate (PCr) levels, and muscle wet/dry weights were determined. Treatment with RP3 selectively and sufficiently depleted the circulating neutrophil population, markedly reduced MPO, and significantly attenuated LPO and the tissue water content after both 3- and 5-hr of ischemia. After 3 hr of ischemia, ATP and PCr levels were significantly increased by neutrophil depletion; however, after 5 hr of ischemia, the same effect was not demonstrated. These results suggest that neutrophil depletion after 3 hr of ischemia restrains free radical production and edema formation, and also attenuates skeletal muscle ischemia reperfusion injury; however, after 5 hr of ischemia, ischemic damage was so severe, that neutrophil depletion did not reduce ischemia reperfusion injury.

Topics: Adenine Nucleotides; Animals; Antibodies, Monoclonal; Hindlimb; Ischemia; Lipid Peroxidation; Male; Muscle, Skeletal; Neutrophils; Peroxidase; Rats; Rats, Inbred Strains; Reperfusion Injury

Splanchnic artery occlusion (SAO) results in a severe form of circulatory shock in which oxygen-derived free radicals play an important role. L-Propionyl carnitine (LPC), an endogenous ester that plays a crucial role in cellular fatty acid oxidation and metabolism, has been shown to exert a protective effect in myocardial ischemia/reperfusion injury. Our purpose was to investigate the effects of LPC in an SAO model of ischemia/reperfusion injury. Pentobarbital-anesthetized rats were subjected to 60 min of SAO followed by 120 min of reperfusion. An intravenous bolus of LPC (200 microg/kg) administered 2 min before reperfusion prolonged survival time (116+/-4 vs. 81+/-3 min in 1 mL/kg .9% NaCl vehicle, p < .01), increased survival rate (88 vs. 13.6%, p < .01), and attenuated the percent increase in hematocrits (27+/4% vs. 43+/-3%, p < .05), and the increases in tissue myeloperoxidase activity (1.76+/-.4 U/100 mg vs. 3.79+/-.2 U/100 mg, p < .05). In addition, LPC increased mean arterial blood pressures at 60 min (p < .05), 80 min (p < .05), 100 min (p < .05), and 120 min (p < .05) postreperfusion. Moreover, LPC markedly attenuated splanchnic artery endothelial dysfunction induced by SAO ischemia/reperfusion injury (maximal vasorelaxation to ACh, 74+/-2.7% vs. 57+/-1.9% in vehicle, p < .01). In this murine SAO model of ischemia/reperfusion injury, LPC affords significant protection that may be achieved through inhibiting leukocyte infiltration into intestinal tissue and preserving endothelial function, thereby decreasing microvascular permeability and maintaining tissue perfusion.

Topics: Animals; Blood Pressure; Carnitine; Endothelium, Vascular; Fatty Acids; Intestines; Male; Mesenteric Arteries; Mesenteric Vascular Occlusion; Neutrophils; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Shock; Splanchnic Circulation; Survival Rate; Time Factors

Because the lungs receive their blood supply from both the pulmonary and bronchial systems, chronic pulmonary artery obstruction does not necessarily result in severe ischemia. Ischemia-reperfusion (IR) lung injury may therefore be attenuated after long-term pulmonary artery obstruction. To test this hypothesis, isolated left lungs of pigs were reperfused two days (acute IR group) or 5 wk (chronic IR group) after left pulmonary artery ligation and compared to those of sham-operated animals. The severity of IR-lung injury after 60 min ex vivo reperfusion of the left lung was assessed based on lung histology and measurements of filtration coefficient (Kfc), pulmonary arterial resistance (Rpa), and lung myeloperoxidase (MPO) activity. Marked bronchial circulation hypertrophy was seen in the chronic IR group. Hemorrhagic alveolar edema was found in all acute IR lungs but not in sham or chronic IR lungs. Compared with the sham-operated controls, Kfc and Rpa increased two-fold and threefold, and MPO 1.5-fold and twofold in the chronic and acute IR groups, respectively. In conclusion, IR-induced lung injury was markedly reduced when it occurred 5 wk after pulmonary artery ligation, probably because the systemic blood supply to the lung had time to develop, limiting ischemia.

Topics: Animals; Capillary Permeability; In Vitro Techniques; Leukocyte Count; Ligation; Lung; Neutrophils; Peroxidase; Pulmonary Artery; Pulmonary Circulation; Reperfusion Injury; Swine; Time Factors; Vascular Resistance

The authors' goal was to determine the effects of specific binding and blockade of P- and E-selectins by a soluble P-selectin glycoprotein ligand-1 (PSGL-1) in rat models of hepatic in vivo warm ischemia and ex vivo cold ischemia. The authors also sought to determine the effect of selectin blockade on isograft survival in a syngeneic rat orthotopic liver transplant model.. Ischemia/reperfusion (I/R) injury is a major factor in poor graft function after liver transplantation, which may profoundly influence early graft function and late changes. It is hypothesized that I/R injury leads to the upregulation of P-selectin, which is then rapidly translocated to endothelial cell surfaces within 5 minutes of reperfusion of the liver, initiating steps leading to tethering of polymorphonuclear neutrophil leukocytes to the vascular intima. Local production by leukocytes of interleukin-1, tumor necrosis factor-alpha, or both induces P-selectin expression on the endothelium and continues the cascade of events, which increases cell adherence and infiltration of the organ.. To examine directly the effects of selectins in a warm hepatic I/R injury model, 100 microg of PSGL-1 or saline was given through the portal vein at the time of total hepatic inflow occlusion. The effects of PSGL-1 in cold ischemia were assessed using an isolated perfused rat liver after 6 hours of 4 degrees C storage in University of Wisconsin (UW) solution, with or without the instillation of PSGL-1 before the storage. To evaluate the effect of selectin blockade on liver transplant survival, syngeneic orthotopic liver transplants were performed between inbred male Sprague-Dawley rats after 24 hours of cold ischemic storage in UW solution. A separate group of animals received two doses of 100 microg of PSGL-1 through the portal vein before storage and before reperfusion of the transplanted liver. Recipient survival was assessed at 7 days, and the Kaplan-Meier product limit estimate method was used for univariate calculations of time-dependent recipient survival events.. In an in vivo warm rat liver ischemia model, perfusion with PSGL-1 afforded considerable protection from I/R injury, as demonstrated by decreased transaminase release, reduced histologic hepatocyte damage, and suppressed neutrophil infiltration, versus controls (p < 0.05). When cold stored livers were reperfused, PSGL-1 reduced the degree of hepatocyte transaminase release, reduced neutrophil infiltration, and decreased histologic hepatocyte damage (p < 0.05 vs. UW-only controls). On reperfusion, livers treated with PSGL-1 demonstrated increased portal vein blood flow and bile production (p < 0.05 vs. UW-only controls). In addition, 90% of the rats receiving liver isografts stored in UW solution supplemented with PSGL-1 survived 7 days versus 50% of those whose transplanted syngeneic livers had been stored in UW alone (p < 0.05).. Selectins play an important role in I/R injury of the liver. Early modulation of the interaction between P-selectin and its ligand decreases hepatocyte injury, neutrophil adhesion, and subsequent migration in both warm and cold rat liver ischemia models. In addition, the use of PSGL-1 before ischemic storage and before transplantation prevents hepatic injury, as documented by a significant increase in liver isograft survival. These findings have important clinical ramifications: early inhibition of alloantigen-independent mechanisms during the I/R damage may influence both short- and long-term survival of liver allografts.

Topics: Animals; Aspartate Aminotransferases; Cell Adhesion; Ligands; Liver Diseases; Liver Transplantation; Male; Membrane Glycoproteins; Mucins; P-Selectin; Peroxidase; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Solubility; Up-Regulation

Ischemia/reperfusion injury (IRI) after free tissue transfer of the small intestine results in transmural tissue damage. This study examined the effects of IRI on the jejunum. Wistar rats served either as controls (N=10) or underwent clamping of the infrarenal aorta for 1 hour followed by 1 hour of reperfusion (N=10). Both ischemia and reperfusion reduced the protein and deoxyribonucleic acid content of the jejunal mucosa (p < 0.05). Myeloperoxidase activity in the jejunal mucosa remained relatively low. The expression of leukocyte function-associated antigen 1 and intercellular adhesion molecule 1 (ICAM-1) on the surface of mucosal cells was not altered significantly by the ischemic insult, but was reduced after the period of reperfusion (p < 0.05). This coincided with an increase in messenger ribonucleic acid (mRNA) for ICAM-1 within isolated mucosal cells (p < 0.05). The specific activity of glutaminase in isolated jejunal mucosal cells was diminished after ischemia and reperfusion (p < 0.05), and this was not associated with an appreciable change in glutaminase mRNA expression. These results have identified some molecular mechanisms underlying IRI of the small intestine that are possible candidates for therapeutic intervention.

Topics: Animals; Immunoenzyme Techniques; Immunohistochemistry; Intercellular Adhesion Molecule-1; Intestinal Mucosa; Jejunum; Lymphocyte Function-Associated Antigen-1; Peroxidase; Rats; Rats, Wistar; Reperfusion Injury; Up-Regulation

A short period of warm ischemia during lung allograft implantation is inevitable. We studied the effect of 2 h of warm ischemia before implantation after 18 h of cold preservation on reperfusion edema and pulmonary hemodynamics in a large animal model.. Left lung transplantation was performed in ten weight-matched pigs (25-31 kg). Donor lungs were flushed with 1.5 l cold (1 degree C) LPD solution and preserved for 20 h. In Group I (n = 5) the grafts were preserved for 20 h at 1 degree C and topically cooled with ice slush during implantation until reperfusion. In Group II (n = 5) lungs were stored at 1 degree C for 18 h followed by 2 h preservation at room temperature (20 degrees C). Topical cooling was not used during implantation. At 1 h after reperfusion the recipient contralateral right pulmonary artery and bronchus were ligated to assess graft function only. Extravascular lung water index (EVLWI), intrathoracic blood volume (ITBV), mean pulmonary artery pressure (PAP) and cardiac output (CO) were assessed during a 4 h observation period. Quantitative myeloperoxidase (MPO) activity and thiobarbituric acid-reactive substance (TBARS) levels as an indicator for lipid peroxidation were determined in allograft tissue samples taken 5 h after reperfusion.. In Group II a tendency to improved pulmonary vascular resistance and cardiac output was noted. Surprisingly, lung edema, assessed by EVLWI, did not increase in animals with warm ischemia. Even a tendency to a reduced EVLWI was noted. However, differences between groups did not reach statistical significance. Gas exchange did not differ statistically significant between groups.. Our results indicate that a short period of warm ischemia before reperfusion does not lead to increased pulmonary edema. In animals with a short period of warm ischemia before reperfusion, even a tendency to reduced posttransplant lung reperfusion injury was noted. In this model, topical graft cooling during lung implantation did not improve posttransplant graft function.

Topics: Animals; Lung Transplantation; Organ Preservation; Peroxidase; Reperfusion Injury; Swine; Temperature; Thiobarbituric Acid Reactive Substances; Time Factors; Transplantation, Homologous

Increased production of oxygen free radicals and infiltration of neutrophils into tissue subjected to ischemia-reperfusion have emphasized that neutrophils play a direct role in the development of injury. The present study was designed to elucidate the effect of FK506, a new immunosuppressive drug, on 11 hours of complete ischemia and reperfusion of the inguinal island skin flaps in rats. Group 1 (n = 10) control animals underwent ischemia and reperfusion and no treatment. Group 2 (n = 10) animals received FK 506 0.3 mg/kg/day, and group 3 (n = 9) animals received 0.5 mg/kg/day intramuscularly for 3 days before the ischemia. The effect of the drug was evaluated by measuring flap survival and tissue malondialdehyde content and myeloperoxidase activity and also by histopathologic examination of the skin specimens taken at the 1st and 24th hour after reperfusion. The survival of flaps controlled for 7 days was found to be significantly improved in group 2 (65.0 +/- 10.93 percent) and group 3 (93 +/- 6.25 percent) when compared with the control group (14 +/- 10.12 percent) (p < 0.04 and p < 0.0001). The tissue contents of malondialdehyde and activities of myeloperoxidase were significantly lower in groups 2 and 3 than in the control group. Three days of pretreatment with FK506 significantly reduced neutrophil infiltration in groups treated with either of the doses. These results showed that neutrophils play an important role in island flap survival associated with ischemia-reperfusion injury. Increased neutrophil infiltration was found related with increased levels of malondialdehyde and myeloperoxidase. Flap necrosis and the increase in malondialdehyde, myeloperoxidase, and neutrophil infiltration were improved by FK506 pretreatment, a neutrophil modulating agent.

Topics: Animals; Free Radicals; Graft Survival; Groin; Immunosuppressive Agents; Injections, Intramuscular; Ischemia; Leukocyte Count; Male; Malondialdehyde; Neutrophil Activation; Neutrophils; Peroxidase; Rats; Rats, Wistar; Reactive Oxygen Species; Reperfusion Injury; Skin; Skin Transplantation; Surgical Flaps; Tacrolimus

Vasoactive intestinal peptide (VIP) has been reported to have some properties that provide protection from lung injury. Furthermore, its protective effect in cold storage of donor lungs has been confirmed. We examined its effect and the timing of administration in an in vivo rat lung transplantation model.. All lungs were flushed with low-potassium dextran-1% glucose solution, and orthotopic left lung transplantations were performed. Rats were divided into four groups (n = 6). Group I received no preservation or storage. Groups II, III, and IV grafts were stored for 18 hours at 4 degrees C. Group II received no VIP. Group III received VIP (0.1 g/ml) via the flush solution. Group IV recipients received VIP (3 microg/kg) intravenously just after reperfusion. Twenty-four hours after transplantation, the right main pulmonary artery and right main bronchus were ligated, and the rats were ventilated with 100% O2 for 5 minutes. Mean pulmonary arterial pressure, peak airway pressure, blood gas analysis, serum lipid peroxide level, tissue myeloperoxidase activity, and wet-dry weight ratio were measured.. The partial O2 tension values of groups III and IV were better than group II (groups II, III, and IV: 147.4 +/- 71.4, 402.1 +/- 64.8, 373.4 +/- 81.0 mm Hg; p < 0.05). Peak airway pressure was lower in groups III and IV than in group II (groups II, III, and IV: 19.7 +/- 0.8, 16.7 +/- 0.9. and 16.3 +/- 1.0 mm Hg; p < 0.05). Mean pulmonary arterial pressure in group III was lower than group II (groups II and III: 36.3 +/- 3.0 and 22.1 +/- 2.2 mm Hg; p < 0.01). Wet-dry weight ratio in group III was lower than in groups II and IV (group II, III, and IV: 5.2 +/- 0.2, 4.4 +/- 0.2, and 5.2 +/- 0.3; II vs III; p < 0.05, III vs IV; p < 0.01). Serum lipid peroxide levels in groups III and IV were significantly lower (groups II, III, and IV: 2.643 +/- 0.913, 0.455 +/- 0.147, and 0.325 +/- 0.124 nmol/ml; p < 0.01).. VIP ameliorates reperfusion injury in an in vivo rat lung transplantation model. Either administration of VIP via the flush solution or systemically just after reperfusion was associated with improved pulmonary function.

Topics: Airway Resistance; Animals; Blood Pressure; Lung; Lung Transplantation; Male; Organ Preservation; Oxygen; Peroxidase; Pulmonary Artery; Rats; Rats, Inbred F344; Reperfusion Injury; Thiobarbituric Acid Reactive Substances; Vasoactive Intestinal Peptide

NPC18915, a member of new antiinflammatory agent called nactins (neutrophil activation inhibitors), has been shown to reduce reperfusion injury in rat lung transplantation at high dosage. In vitro studies have demonstrated effectiveness of this compound even at low dosage. We hypothesized that this compound ameliorates lung ischemia reperfusion injury even at low dosage levels if administration is optimally timed. The aim of this study was to determine the efficacy and the best timing for administration of low-dose NPC18915.. Forty syngeneic rat left lung transplantations were performed. All isografts were flushed with low-potassium dextran-1% glucose solution 20 ml and preserved for 18 hours at 4 degrees C. Animals were divided into four groups. Group I animals (n = 10) served as control subjects. In groups II (n = 10), III (n = 10), and IV (n = 10), NPC18915 (0.04 mg) was added to the flush solution and was administered intravenously (0.4 mg/kg) immediately before reperfusion (group II) and 60 minutes (group III) and 120 minutes (group IV) after reperfusion. Pulmonary function was assessed 24 hours after reperfusion.. In group III, oxygenation improved in comparison to group I (247.2 +/- 59.8 versus 76.6 +/- 16.0 mm Hg, p < 0.002). Wet-to-dry weight ratio and graft myeloperoxidase activity were significantly improved (group III versus group I, 6.02 +/- 0.21 versus 7.19 +/- 0.41, p = 0.013) (group III versus group I, 0.093 +/- 0.019 versus 0.207 +/- 0.023 delta optical density/min/mg, p < 0.002). There were no significant differences in CD11b expression.. These data suggest that delayed administration of NPC18915, 60 minutes after reperfusion, dramatically improves pulmonary graft function.

Topics: Animals; Benzoates; Benzofurans; Flow Cytometry; Lung; Lung Transplantation; Macrophage-1 Antigen; Neutrophils; Organ Preservation; Oxygen; Peroxidase; Rats; Rats, Inbred F344; Reperfusion Injury

Soluble complement receptor type 1 inhibits complement activation by blocking C3 and C5 convertases of the classical and alternative pathways. We evaluated the effect of soluble complement receptor type 1 on lung allograft reperfusion injury.. Left lung transplantation was performed in 13 weight-matched pigs (25 to 31 kg) after prolonged preservation (20 hours at 1 degree C). One hour after reperfusion the recipient contralateral right lung was excluded to assess graft function only. Complement activity and C3a levels were measured after reperfusion and at the end of the assessment. Extravascular lung water index, intrathoracic blood volume, and cardiac output were assessed during a 5-hour observation period. Gas exchange and hemodynamics were monitored. At the end of the 5-hour assessment period, myeloperoxidase assay and bronchoalveolar lavage were performed to assess neutrophil migration, and C5b-9 (membrane attack complex) deposits in the allograft were detected by immunohistochemistry. Two groups were studied. In group II (n = 6) recipient animals were treated with soluble complement receptor type 1 (15 mg/kg) 15 minutes before reperfusion. Group I (n = 7) served as the control group.. Serum complement activity was completely inhibited in group II. In contrast to group I, C5b-9 complexes were not detected in group II allograft tissue samples. C3a was reduced to normal levels in group II (p = 0.00005). Extravascular lung water index was higher in group I animals throughout the assessment period (p = 0.035). No significant difference in allograft myeloperoxidase activity (p = 0.10) and polymorphonuclear leukocyte count of the bronchoalveolar lavage fluid (p = 0.057) was detected.. Inhibition of the complement system by soluble complement receptor type 1 blocks local complement activation in the allograft and reduces posttransplantation reperfusion edema but does not improve hemodynamic parameters.

Topics: Animals; Chemotaxis, Leukocyte; Complement Activation; Complement System Proteins; Dogs; Extravascular Lung Water; Hemodynamics; Immunohistochemistry; Lung Transplantation; Neutrophils; Peroxidase; Pulmonary Edema; Receptors, Complement; Recombinant Proteins; Reperfusion Injury; Swine; Transplantation, Homologous