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Sample records for oxygen reperfusion damage

  1. The role of xanthine oxidase in ischemia/reperfusion damage of rat liver

    Frederiks, W. M.; Bosch, K. S.

    1995-01-01

    Oxygen radicals have been proposed to be involved in the induction of liver cell damage during reperfusion after ischemia. The role of xanthine oxidase in this process and the potential of the antioxidant system have been studied in a model of in vivo ischemia of rat liver followed by 1 h

  2. Gradual reintroduction of oxygen reduces reperfusion injury in cat stomach

    Perry, M.A.; Wadhwa, S.S.

    1988-01-01

    Recent studies have shown that oxygen-derived free radicals are responsible for a major portion of ischemia-reperfusion injury in the stomach. The oxygen radicals are produced during perfusion when oxygen delivery to the tissue increases. In the present study the authors investigate the effect on mucosal injury of regulating the rate of reintroduction of oxygen to the stomach after ischemia. Local gastric ischemia was achieved by reducing celiac artery pressure to 30 mmHg for 1 h. Ischemic injury was assessed by measuring the loss of 51 Cr-labeled red blood cells across the gastric mucosa. Mucosal blood loss was negligible before and during the ischemia period but increased during reperfusion. When blood flow to the stomach was gradually returned to normal after ischemia, the mucosal blood loss was reduced. If the stomach was vascularly perfused with low Po 2 blood for 1 h after ischemia before being returned to normal arterial perfusion, the mucosal blood loss was also reduced. When the stomach was made hypoxemic for 1 h rather than ischemic by perfusing the vasculature with low Po 2 blood then reperfused with normoxic blood, there was very little mucosal bleeding. The data indicate that gastric mucosal bleeding after ischemia is reduced if the tissue is returned slowly to a normal Po 2 . These findings support the concept that reperfusion injury is due largely to the production of oxygen radicals. The low level of injury produced by hypoxemia indicates that hypoxia per se makes only a minor contribution to reperfusion injury in the stomach

  3. Dynamic mechanisms of cardiac oxygenation during brief ischemia and reperfusion

    Parsons, W.J.; Rembert, J.C.; Bauman, R.P.; Greenfield, J.C. Jr.; Piantadosi, C.A.

    1990-01-01

    Myocardial oxygenation may be altered markedly by changes in tissue blood flow. During brief ischemia and reperfusion produced by transient occlusion of the left anterior descending artery in 10 open-chest dogs, changes in the oxygenation of tissue hemoglobin (Hb) plus myoglobin (Mb) and the oxidation-reduction (redox) state of mitochondrial cytochrome aa3 were monitored continuously using near-infrared spectroscopy. The nondestructive optical technique indicated that coronary occlusion produced an abrupt drop in tissue oxygen stores (tHb02 + Mb02), tissue blood volume (tBV), and the oxidation level of cytochrome aa3. Changes in the cytochrome oxidation state were related inversely to transmural collateral blood flow within the ischemic region (r = 0.77) measured with radiolabeled microspheres. Furthermore, there was a direct relationship (r = 0.91) between collateral blood flow and the tissue level of desaturated Hb and Mb (tHb + Mb). Reperfusion after 2 min of ischemia led to a synchronous overshoot of baseline in coronary flow and tBV followed by supranormal increases in tHb + Mb02 and the oxidation level of cytochrome aa3. The tHb + Mb level increased transiently during reperfusion. This response correlated inversely with collateral flow during ischemia (r = 0.91). Accordingly, the time required to reach peak tHb + Mb levels was shortest in dogs with high collateral flows (r = 0.75). Thus collateral blood flow partially sustains myocardial oxygenation during coronary artery occlusion and influences tissue reoxygenation early during reperfusion

  4. Bicarbonate modulates oxidative and functional damage in ischemia-reperfusion.

    Queliconi, Bruno B; Marazzi, Thire B M; Vaz, Sandra M; Brookes, Paul S; Nehrke, Keith; Augusto, Ohara; Kowaltowski, Alicia J

    2013-02-01

    The carbon dioxide/bicarbonate (CO(2)/HCO(3)(-)) pair is the main biological pH buffer. However, its influence on biological processes, and in particular redox processes, is still poorly explored. Here we study the effect of CO(2)/HCO(3)(-) on ischemic injury in three distinct models (cardiac HL-1 cells, perfused rat heart, and Caenorhabditis elegans). We found that, although various concentrations of CO(2)/HCO(3)(-) do not affect function under basal conditions, ischemia-reperfusion or similar insults in the presence of higher CO(2)/HCO(3)(-) resulted in greater functional loss associated with higher oxidative damage in all models. Because the effect of CO(2)/HCO(3)(-) was observed in all models tested, we believe this buffer is an important determinant of oxidative damage after ischemia-reperfusion. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Antiarrhythmic effect of tamoxifen on the vulnerability induced by hyperthyroidism to heart ischemia/reperfusion damage.

    Pavón, Natalia; Hernández-Esquivel, Luz; Buelna-Chontal, Mabel; Chávez, Edmundo

    2014-09-01

    Hyperthyroidism, known to have deleterious effects on heart function, and is associated with an enhanced metabolic state, implying an increased production of reactive oxygen species. Tamoxifen is a selective antagonist of estrogen receptors. These receptors make the hyperthyroid heart more susceptible to ischemia/reperfusion. Tamoxifen is also well-known as an antioxidant. The aim of the present study was to explore the possible protective effect of tamoxifen on heart function in hyperthyroid rats. Rats were injected daily with 3,5,3'-triiodothyronine at 2mg/kg body weight during 5 days to induce hyperthyroidism. One group was treated with 10mg/kg tamoxifen and another was not. The protective effect of the drug on heart rhythm was analyzed after 5 min of coronary occlusion followed by 5 min reperfusion. In hyperthyroid rats not treated with tamoxifen, ECG tracings showed post-reperfusion arrhythmias, and heart mitochondria isolated from the ventricular free wall lost the ability to accumulate and retain matrix Ca(2+) and to form a high electric gradient. Both of these adverse effects were avoided with tamoxifen treatment. Hyperthyroidism-induced oxidative stress caused inhibition of cis-aconitase and disruption of mitochondrial DNA, effects which were also avoided by tamoxifen treatment. The current results support the idea that tamoxifen inhibits the hypersensitivity of hyperthyroid rat myocardium to reperfusion damage, probably because its antioxidant activity inhibits the mitochondrial permeability transition. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Receptor for advanced glycation end products involved in lung ischemia reperfusion injury in cardiopulmonary bypass attenuated by controlled oxygen reperfusion in a canine model.

    Rong, Jian; Ye, Sheng; Liang, Meng-ya; Chen, Guang-xian; Liu, Hai; Zhang, Jin-Xin; Wu, Zhong-kai

    2013-01-01

    Controlled oxygen reperfusion could protect the lung against ischemia-reperfusion injury in cardiopulmonary bypass (CPB) by downregulating high mobility group box 1 (HMGB1), a high affinity receptor of HMGB1. This study investigated the effect of controlled oxygen reperfusion on receptor for advanced glycation end products (RAGE) expression and its downstream effects on lung ischemia-reperfusion injury. Fourteen canines received CPB with 60 minutes of aortic clamping and cardioplegic arrest followed by 90 minutes of reperfusion. Animals were randomized to receive 80% FiO2 during the entire procedure (control group) or to a test group receiving a controlled oxygen reperfusion protocol. Pathologic changes in lung tissues, RAGE expression, serum interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) were evaluated. The lung pathologic scores after 25 and 90 minutes of reperfusion were significantly lower in the test group compared with the control group (p RAGE expression, TNF-α, and IL-6 were downregulated by controlled oxygen treatment (p RAGE might be involved in the lung ischemia-reperfusion injury in canine model of CPB, which was downregulated by controlled oxygen reperfusion.

  7. Neuroprotective role of nanoencapsulated quercetin in combating ischemia-reperfusion induced neuronal damage in young and aged rats.

    Aparajita Ghosh

    Full Text Available Cerebral stroke is the leading cause of death and permanent disability among elderly people. In both humans and animals, cerebral ischemia damages the nerve cells in vulnerable regions of the brain, viz., hippocampus, cerebral cortex, cerebellum, and hypothalamus. The present study was conducted to evaluate the therapeutic efficacy of nanoencapsulated quercetin (QC in combating ischemia-reperfusion-induced neuronal damage in young and aged Swiss Albino rats. Cerebral ischemia was induced by occlusion of the common carotid arteries of both young and aged rats followed by reperfusion. Nanoencapsulated quercetin (2.7 mg/kg b wt was administered to both groups of animals via oral gavage two hours prior to ischemic insults as well as post-operation till day 3. Cerebral ischemia and 30 min consecutive reperfusion caused a substantial increase in lipid peroxidation, decreased antioxidant enzyme activities and tissue osmolality in different brain regions of both groups of animals. It also decreased mitochondrial membrane microviscosity and increased reactive oxygen species (ROS generation in different brain regions of young and aged rats. Among the brain regions studied, the hippocampus appeared to be the worst affected region showing increased upregulation of iNOS and caspase-3 activity with decreased neuronal count in the CA1 and CA3 subfields of both young and aged rats. Furthermore, three days of continuous reperfusion after ischemia caused massive damage to neuronal cells. However, it was observed that oral treatment of nanoencapsulated quercetin (2.7 mg/kg b wt resulted in downregulation of iNOS and caspase-3 activities and improved neuronal count in the hippocampal subfields even 3 days after reperfusion. Moreover, the nanoformulation imparted a significant level of protection in the antioxidant status in different brain regions, thus contributing to a better understanding of the given pathophysiological processes causing ischemic neuronal damage.

  8. DRAM1 Protects Neuroblastoma Cells from Oxygen-Glucose Deprivation/Reperfusion-Induced Injury via Autophagy

    Mengqiang Yu

    2014-10-01

    Full Text Available DNA damage-regulated autophagy modulator protein 1 (DRAM1, a multi-pass membrane lysosomal protein, is reportedly a tumor protein p53 (TP53 target gene involved in autophagy. During cerebral ischemia/reperfusion (I/R injury, DRAM1 protein expression is increased, and autophagy is activated. However, the functional significance of DRAM1 and the relationship between DRAM1 and autophagy in brain I/R remains uncertain. The aim of this study is to investigate whether DRAM1 mediates autophagy activation in cerebral I/R injury and to explore its possible effects and mechanisms. We adopt the oxygen-glucose deprivation and reperfusion (OGD/R Neuro-2a cell model to mimic cerebral I/R conditions in vitro, and RNA interference is used to knock down DRAM1 expression in this model. Cell viability assay is performed using the LIVE/DEAD viability/cytotoxicity kit. Cell phenotypic changes are analyzed through Western blot assays. Autophagy flux is monitored through the tandem red fluorescent protein–Green fluorescent protein–microtubule associated protein 1 light chain 3 (RFP–GFP–LC3 construct. The expression levels of DRAM1 and microtubule associated protein 1 light chain 3II/I (LC3II/I are strongly up-regulated in Neuro-2a cells after OGD/R treatment and peaked at the 12 h reperfusion time point. The autophagy-specific inhibitor 3-Methyladenine (3-MA inhibits the expression of DRAM1 and LC3II/I and exacerbates OGD/R-induced cell injury. Furthermore, DRAM1 knockdown aggravates OGD/R-induced cell injury and significantly blocks autophagy through decreasing autophagosome-lysosome fusion. In conclusion, our data demonstrate that DRAM1 knockdown in Neuro-2a cells inhibits autophagy by blocking autophagosome-lysosome fusion and exacerbated OGD/R-induced cell injury. Thus, DRAM1 might constitute a new therapeutic target for I/R diseases.

  9. The effects of deformation, ischemia, and reperfusion on the development of muscle damage during prolonged loading

    Loerakker, S.; Manders, E.; Strijkers, G.J.; Nicolay, K.; Baaijens, F.P.T.; Bader, D.L.; Oomens, C.W.J.

    2011-01-01

    Deep tissue injury (DTI) is a severe form of pressure ulcer where tissue damage starts in deep tissues underneath intact skin. In the present study, the contributions of deformation, ischemia, and reperfusion to skeletal muscle damage development were examined in a rat model during a 6-h period.

  10. Effect of desferrioxamine on reperfusion damage of rat heart ...

    1990-09-01

    Sep 1, 1990 ... ... deferrioxamine on rat heart mitochondrial oxidative phosphorylation after normothermic ischemic cardiac arrest and of reperfusion. Res Commun Chem Pathol Pharmacol 1988;. 62: 419-434. IL Sordahl LA, Johnson C, Blailock ZR. Schwartz A. The mitochondrion. Mechods Phannacol1971; 1: 247-286.

  11. Prevention of reperfusion lung injury by lidocaine in isolated rat lung ventilated with higher oxygen levels.

    Das K

    2003-01-01

    Full Text Available BACKGROUND: Lidocaine, an antiarrhythmic drug has been shown to be effective against post-ischaemic reperfusion injury in heart. However, its effect on pulmonary reperfusion injury has not been investigated. AIMS: We investigated the effects of lidocaine on a postischaemic reperfused rat lung model. MATERIALS AND METHODS: Lungs were isolated and perfused at constant flow with Krebs-Henseilet buffer containing 4% bovine serum albumin, and ventilated with 95% oxygen mixed with 5% CO2. Lungs were subjected to ischaemia by stopping perfusion for 60 minutes followed by reperfusion for 10 minutes. Ischaemia was induced in normothermic conditions. RESULTS: Postischaemic reperfusion caused significant (p < 0.0001 higher wet-to-dry lung weight ratio, pulmonary arterial pressure and peak airway pressure compared to control lungs. Lidocaine, at a dose of 5mg/Kg b.w. was found to significantly (p < 0.0001 attenuate the increase in the wet-to-dry lung weight ratio, pulmonary arterial pressure and peak airway pressure observed in post-ischaemic lungs. CONCLUSION: Lidocaine is effective in preventing post-ischaemic reperfusion injury in isolated, perfused rat lung.

  12. Platelets Orchestrate Remote Tissue Damage After Mesenteric Ischemia-Reperfusion

    2012-02-02

    Platelet Depletion Two days before I/R injury, mice received a single intraperitoneal injection of a titred affinity purified endotoxin-free rabbit...Egan R, Chen J, le Lucca JJ, Juang YT, Tsokos GC. IL-17 producing CD4 T cells mediate accelerated ischemia/reperfusion- induced injury in...activation in rheumatoid arthritis. Clin Rheumatol 26: 768–771, 2007. 77. Wang Y, Li Y, le Lucca SL, Simovic M, Tsokos GC, le Lucca JJ. Decay accelerating

  13. Noscapine protects OLN-93 oligodendrocytes from ischemia-reperfusion damage: Calcium and nitric oxide involvement.

    Nadjafi, S; Ebrahimi, S-A; Rahbar-Roshandel, N

    2015-12-01

    This study was carried out to evaluate the effects of noscapine, a benzylisoquinoline alkaloid from opium poppy, on oligodendrocyte during ischemia/reperfusion-induced excitotoxic injury. Changes in intracellular calcium levels due to chemical ischemia and nitric oxide (NO) production during ischemia/reperfusion were evaluated as the hallmarks of ischemia-derived excitotoxic event. OLN-93 cell line (a permanent immature rat oligodendrocyte) was used as a model of oligodendrocyte. 30- or 60-minute-oxygen-glucose deprivation/24 hours reperfusion were used to induce excitotoxicity. MTT (3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) assay was used to evaluate cell viability. Ratiometric fluorescence microscopy using Ca(2+)-sensitive indicator Fura-2/AM was utilized to assess intracellular calcium levels. NO production was evaluated by Griess method. Noscapine (4 μM) significantly attenuated intracellular Ca(2+) elevation (P < 0.001). Also, noscapine significantly decreased NO production during a 30-minute oxygen-glucose deprivation/reperfusion (P < 0.01). The inhibitory effect of noscapine (4 μM) on intracellular Ca(2+) was greater than ionotropic glutamate receptors antagonists. Noscapine is protective against ischemia/reperfusion-induced excitotoxic injury in OLN-93 oligodendrocyte. This protective effect seems to be related to attenuation of intracellular Ca(2+) overload and NO production.

  14. Cardioprotective properties of citicoline against hyperthyroidism-induced reperfusion damage in rat hearts.

    Hernández-Esquivel, Luz; Pavón, Natalia; Buelna-Chontal, Mabel; González-Pacheco, Héctor; Belmont, Javier; Chávez, Edmundo

    2015-06-01

    Hyperthyroidism represents an increased risk factor for cardiovascular morbidity, especially when the heart is subjected to an ischemia/reperfusion process. The aim of this study was to explore the possible protective effect of the nucleotide citicoline on the susceptibility of hyperthyroid rat hearts to undergo reperfusion-induced damage, which is associated with mitochondrial dysfunction. Hence, we analyzed the protective effect of citicoline on the electrical behavior and on the mitochondrial function in rat hearts. Hyperthyroidism was established after a daily i.p. injection of triiodothyronine (at 2 mg/kg of body weight) during 5 days. Thereafter, citicoline was administered i.p. (at 125 mg/kg of body weight) for 5 days. In hyperthyroid rat hearts, citicoline protected against reperfusion-induced ventricular arrhythmias. Moreover, citicoline maintained the accumulation of mitochondrial Ca(2+), allowing mitochondria to reach a high transmembrane electric gradient that protected against the release of cytochrome c. It also preserved the activity of the enzyme aconitase that inhibited the release of cytokines. The protection also included the inhibition of oxidative stress-induced mDNA disruption. We conclude that citicoline protects against the reperfusion damage that is found in the hyperthyroid myocardium. This effect might be due to its inhibitory action on the permeability transition in mitochondria.

  15. The effects of deformation, ischemia, and reperfusion on the development of muscle damage during prolonged loading.

    Loerakker, S; Manders, E; Strijkers, G J; Nicolay, K; Baaijens, F P T; Bader, D L; Oomens, C W J

    2011-10-01

    Deep tissue injury (DTI) is a severe form of pressure ulcer where tissue damage starts in deep tissues underneath intact skin. In the present study, the contributions of deformation, ischemia, and reperfusion to skeletal muscle damage development were examined in a rat model during a 6-h period. Magnetic resonance imaging (MRI) was used to study perfusion (contrast-enhanced MRI) and tissue integrity (T2-weighted MRI). The levels of tissue deformation were estimated using finite element models. Complete ischemia caused a gradual homogeneous increase in T2 (∼20% during the 6-h period). The effect of reperfusion on T2 was highly variable, depending on the anatomical location. In experiments involving deformation, inevitably associated with partial ischemia, a variable T2 increase (17-66% during the 6-h period) was observed reflecting the significant variation in deformation (with two-dimensional strain energies of 0.60-1.51 J/mm) and ischemia (50.8-99.8% of the leg) between experiments. These results imply that deformation, ischemia, and reperfusion all contribute to the damage process during prolonged loading, although their importance varies with time. The critical deformation threshold and period of ischemia that cause muscle damage will certainly vary between individuals. These variations are related to intrinsic factors, such as pathological state, which partly explain the individual susceptibility to the development of DTI and highlight the need for regular assessments of individual subjects.

  16. Early spontaneous intermittent myocardial reperfusion during acute myocardial infarction is associated with augmented thrombogenic activity and less myocardial damage

    Haider, A.W.; Andreotti, F.; Hackett, D.R.; Tousoulis, D.; Kluft, C.; Maseri, A.; Davies, G.J.

    1995-01-01

    Objectives. This study investigated the influence of early spontaneous intermittent reperfusion on the extent of myocardial damage and its relation to endogenous hemostatic activity, Background. In the early phase of acute myocardial infarction coronary occlusion is often intermittent, even before

  17. Variable Ventilation Improved Respiratory System Mechanics and Ameliorated Pulmonary Damage in a Rat Model of Lung Ischemia-Reperfusion.

    Soluri-Martins, André; Moraes, Lillian; Santos, Raquel S; Santos, Cintia L; Huhle, Robert; Capelozzi, Vera L; Pelosi, Paolo; Silva, Pedro L; de Abreu, Marcelo Gama; Rocco, Patricia R M

    2017-01-01

    Lung ischemia-reperfusion injury remains a major complication after lung transplantation. Variable ventilation (VV) has been shown to improve respiratory function and reduce pulmonary histological damage compared to protective volume-controlled ventilation (VCV) in different models of lung injury induced by endotoxin, surfactant depletion by saline lavage, and hydrochloric acid. However, no study has compared the biological impact of VV vs. VCV in lung ischemia-reperfusion injury, which has a complex pathophysiology different from that of other experimental models. Thirty-six animals were randomly assigned to one of two groups: (1) ischemia-reperfusion (IR), in which the left pulmonary hilum was completely occluded and released after 30 min; and (2) Sham, in which animals underwent the same surgical manipulation but without hilar clamping. Immediately after surgery, the left (IR-injured) and right (contralateral) lungs from 6 animals per group were removed, and served as non-ventilated group (NV) for molecular biology analysis. IR and Sham groups were further randomized to one of two ventilation strategies: VCV ( n = 6/group) [tidal volume (V T ) = 6 mL/kg, positive end-expiratory pressure (PEEP) = 2 cmH 2 O, fraction of inspired oxygen (FiO 2 ) = 0.4]; or VV, which was applied on a breath-to-breath basis as a sequence of randomly generated V T values ( n = 1200; mean V T = 6 mL/kg), with a 30% coefficient of variation. After 5 min of ventilation and at the end of a 2-h period (Final), respiratory system mechanics and arterial blood gases were measured. At Final, lungs were removed for histological and molecular biology analyses. Respiratory system elastance and alveolar collapse were lower in VCV than VV (mean ± SD, VCV 3.6 ± 1.3 cmH 2 0/ml and 2.0 ± 0.8 cmH 2 0/ml, p = 0.005; median [interquartile range], VCV 20.4% [7.9-33.1] and VV 5.4% [3.1-8.8], p = 0.04, respectively). In left lungs of IR animals, VCV increased the expression of interleukin-6 and

  18. Variable Ventilation Improved Respiratory System Mechanics and Ameliorated Pulmonary Damage in a Rat Model of Lung Ischemia-Reperfusion

    Patricia R. M. Rocco

    2017-05-01

    Full Text Available Lung ischemia-reperfusion injury remains a major complication after lung transplantation. Variable ventilation (VV has been shown to improve respiratory function and reduce pulmonary histological damage compared to protective volume-controlled ventilation (VCV in different models of lung injury induced by endotoxin, surfactant depletion by saline lavage, and hydrochloric acid. However, no study has compared the biological impact of VV vs. VCV in lung ischemia-reperfusion injury, which has a complex pathophysiology different from that of other experimental models. Thirty-six animals were randomly assigned to one of two groups: (1 ischemia-reperfusion (IR, in which the left pulmonary hilum was completely occluded and released after 30 min; and (2 Sham, in which animals underwent the same surgical manipulation but without hilar clamping. Immediately after surgery, the left (IR-injured and right (contralateral lungs from 6 animals per group were removed, and served as non-ventilated group (NV for molecular biology analysis. IR and Sham groups were further randomized to one of two ventilation strategies: VCV (n = 6/group [tidal volume (VT = 6 mL/kg, positive end-expiratory pressure (PEEP = 2 cmH2O, fraction of inspired oxygen (FiO2 = 0.4]; or VV, which was applied on a breath-to-breath basis as a sequence of randomly generated VT values (n = 1200; mean VT = 6 mL/kg, with a 30% coefficient of variation. After 5 min of ventilation and at the end of a 2-h period (Final, respiratory system mechanics and arterial blood gases were measured. At Final, lungs were removed for histological and molecular biology analyses. Respiratory system elastance and alveolar collapse were lower in VCV than VV (mean ± SD, VCV 3.6 ± 1.3 cmH20/ml and 2.0 ± 0.8 cmH20/ml, p = 0.005; median [interquartile range], VCV 20.4% [7.9–33.1] and VV 5.4% [3.1–8.8], p = 0.04, respectively. In left lungs of IR animals, VCV increased the expression of interleukin-6 and intercellular

  19. Protective Effect of Alpha Lipoic Acid on Rat Sciatic Nerve Ischemia Reperfusion Damage

    Ozan Turamanlar

    2015-06-01

    Full Text Available Background: Alpha lipoic acid is a potent antioxidant that plays numerous roles in human health. This study examined the effect of ALA on rat sciatic nerve ischemia reperfusion damage. Aims: Protective effect of alpha lipoic acid (ALA on sciatic nerve following ischemia-reperfusion in rats was investigated by using light microscopy and biochemical methods. Provided that the protective effect of ALA on sciatic nerve is proven, we think the damage to the sciatic nerve that has already occurred or might occur in patients for various reasons maybe prevented or stopped by giving ALA in convenient doses. Study Design: Animal experiment. Methods: Forty-two adult male Sprague-Dawley rats (250-300 grams were used in this study. Rats were randomly divided into six groups including one control (Group 1, one sham (Group 2, two ischemia-reperfusion (Groups 3 and 4 and two treatment groups (Groups5 and 6. Doses of 60 and 100 mg/kg ALA were given (Group 5 and 6 intra peritoneally twice, 1 and 24 hours before the ischemia to each treatment group. Ischemia was carried out the abdominal aorta starting from the distal part of the renal vein for two hours followed by reperfusion for three hours. In immunohistochemical methods, fibronectin immunoreactivity was analyzed. For biochemical analyses, the tissues were taken in eppendorf microtubes and superoxide dismutase (SOD and glutathione peroxidase (GSHPx enzyme activities as well as malondialdehyde (MDA and nitricoxide (NO levels were measured. Results: Fibronectin was observed to have increased significantly in the ischemia group; on the other hand, it was observed to have decreased in parallel to the doses in the ALA groups. Biochemical studies showed that SOD and GSHPx declined with ischemia-reperfusion, but the activities of these enzymes were increased in the treatment groups in parallel with the dose. It was found that increased MDA levels with ischemia-reperfusion were decreased in parallel with ALA dose

  20. Dietary broccoli sprouts protect against myocardial oxidative damage and cell death during ischemia-reperfusion.

    Akhlaghi, Masoumeh; Bandy, Brian

    2010-09-01

    Cruciferous vegetables are known for antioxidant and anti-carcinogenic effects. In the current study we asked whether dietary broccoli sprouts can protect the heart from ischemia-reperfusion. Rats were fed either control diet (sham and control groups) or a diet mixed with 2% dried broccoli sprouts for 10 days. After 10 days the isolated hearts were subjected to ischemia for 20 min and reperfusion for 2 h, and evaluated for cell death, oxidative damage, and Nrf2-regulated phase 2 enzyme activities. Broccoli sprouts feeding inhibited markers of necrosis (lactate dehydrogenase release) and apoptosis (caspase-3 activity) by 78-86%, and decreased indices of oxidative stress (thiobarbituric acid reactive substances and aconitase inactivation) by 82-116%. While broccoli sprouts increased total glutathione and activities of the phase 2 enzymes glutamate cysteine ligase and quinone reductase in liver, they did not affect these in ischemic-reperfused heart. While the mechanism is not clear, the results show that a relatively short dietary treatment with broccoli sprouts can strongly protect the heart against oxidative stress and cell death caused by ischemia-reperfusion.

  1. [Identification of early irreversible damage area in a rat model of cerebral ischemia and reperfusion].

    Liu, S; Guo, Y

    2000-02-01

    To observe the early neuron ischemic damage in focal cerebral ischemia/reperfusion with histostaining methods of argyrophil III (AG III), Toludine blue(TB), and H&E, and to make out the 'separating line' between the areas of reversible and irreversible early ischemic damage. Forty-two male Wistar rats were randomly divided into the following groups: pseudo-surgical, blank-control, O2R0(occluded for 2 hours and reperfused for 0 hour), O2R0.5, O2R2, O2R4, O2R24. There were 6 rats in each group. Rats in experimental groups were suffered focal cerebral ischemia/reperfusion through a nylon suture method. After a special processor for tissue manage, the brain were coronal sectioned and stained with H&E, TB, and AG III. The area where dark neurons dwell in (ischemic core) were calculated with image analysis system. The success rate of ischemic model for this experiment is 90%. After being stained with argyrophil III method, normal neurons appear yellow or pale brown, which is hardly distinguished from the pale brown background. The ischemic neuron stained black, and has collapsed body and "corkscrew-like" axon or dentries, which were broken to some extent. The neuropil in the dark neurons dwelt area appears gray or pale black, which is apparently different from the pale brown neighborhood area. The distribution of dark neurons in cortex varies according to different layers, and has a character of columnar form. The dark neurons present as early as 2 hours ischemia without reperfusion with AG III method. AG III stain could selectively display early ischemic neurons, the area dwelt by dark neurons represent early ischemic core. Dark neuron is possibly the irreversibly damaged neuron. Identification of dark neurons could be helpful in the discrimination between early ischemic center and penumbra.

  2. Effects of acetylpuerarin on hippocampal neurons and intracellular free calcium subjected to oxygen-glucose deprivation/reperfusion in primary culture.

    Liu, Rui; Wei, Xin-bing; Zhang, Xiu-Mei

    2007-05-25

    This study was undertaken to find out the effects of acetylpuerarin on hippocampal neurons and intracellular free calcium in primary culture subjected to oxygen-glucose deprivation/reperfusion. According to different reperfusion time (1 h, 6 h, 12 h, 24 h), three concentrations (1.6 micromol l(-1), 0.4 micromol l(-1), 0.1 micromol l(-1)) of acetylpuerarin, and MK-801 (10 micromol l(-1)), a positive control drug, neurons were randomly divided into 21 groups. Each group was observed by inverted phase contrast microscope; neuron viability was measured by the reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT); intracellular Ca(2+) was observed by Fura-2/AM ester through fluorospectrophotometer. The injured neurons were protected and degeneration and necrosis were alleviated in treatment groups of acetylpuerarin and MK-801. Acetylpuerarin increased the neuron viability at high, middle and low concentrations. Fluorescence detection results showed that the calcium concentration in the group treated with acetylpuerarin and MK-801 was lowered in each reperfusion time. Our results demonstrated that acetylpuerarin could protect the hippocampal neurons from ischemia-reperfusion injury in rats by alleviating the morphological damage, increasing neuron viability and decreasing calcium concentration in neuron.

  3. Effect of Nigella sativa on ischemia-reperfusion induced rat kidney damage

    Shahrzad Havakhah

    2015-12-01

    Full Text Available Objective(s:There are a few previously reported studies about the effect of Nigella sativa oil on renal ischemia-reperfusion injury (IRI. The aim of the present study was to test the hypothesis whether pre- or post-treatment with N. sativa hydroalcoholic extract (NSE would reduce tissue injury and oxidative damages in a clinically relevant rat model of renal IRI.    Materials and Methods: IRI was induced by clamping of bilateral renal arteries for 40 min fallowed by reperfusion for 180 min. NSE was prepared in a Soxhlet extractor and administrated with doses of 150 mg/kg or 300 mg/kg at 1 hr before ischemia induction (P-150 and 300 or at the beginning of reperfusion phase (T-150 and 300, via jugular catheter intravenously. The kidneys were then removed and subjected to biochemical analysis, comet assay or histopathological examination. Results: The kidneys of untreated IRI rats had a higher histopathological score (P

  4. Selective Cannabinoid 2 Receptor Stimulation Reduces Tubular Epithelial Cell Damage after Renal Ischemia-Reperfusion Injury.

    Pressly, Jeffrey D; Mustafa, Suni M; Adibi, Ammaar H; Alghamdi, Sahar; Pandey, Pankaj; Roy, Kuldeep K; Doerksen, Robert J; Moore, Bob M; Park, Frank

    2018-02-01

    Ischemia-reperfusion injury (IRI) is a common cause of acute kidney injury (AKI), which is an increasing problem in the clinic and has been associated with elevated rates of mortality. Therapies to treat AKI are currently not available, so identification of new targets that can be modulated to ameliorate renal damage upon diagnosis of AKI is essential. In this study, a novel cannabinoid receptor 2 (CB2) agonist, SMM-295 [3'-methyl-4-(2-(thiophen-2-yl)propan-2-yl)biphenyl-2,6-diol], was designed, synthesized, and tested in vitro and in silico. Molecular docking of SMM-295 into a CB2 active-state homology model showed that SMM-295 interacts well with key amino acids to stabilize the active state. In human embryonic kidney 293 cells, SMM-295 was capable of reducing cAMP production with 66-fold selectivity for CB2 versus cannabinoid receptor 1 and dose-dependently increased mitogen-activated protein kinase and Akt phosphorylation. In vivo testing of the CB2 agonist was performed using a mouse model of bilateral IRI, which is a common model to mimic human AKI, where SMM-295 was immediately administered upon reperfusion of the kidneys after the ischemia episode. Histologic damage assessment 48 hours after reperfusion demonstrated reduced tubular damage in the presence of SMM-295. This was consistent with reduced plasma markers of renal dysfunction (i.e., creatinine and neutrophil gelatinase-associated lipocalin) in SMM-295-treated mice. Mechanistically, kidneys treated with SMM-295 were shown to have elevated activation of Akt with reduced terminal deoxynucleotidyl transferase-mediated digoxigenin-deoxyuridine nick-end labeling (TUNEL)-positive cells compared with vehicle-treated kidneys after IRI. These data suggest that selective CB2 receptor activation could be a potential therapeutic target in the treatment of AKI. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

  5. Laser Speckle Imaging of Rat Pial Microvasculature during Hypoperfusion-Reperfusion Damage

    Teresa Mastantuono

    2017-09-01

    Full Text Available The present study was aimed to in vivo assess the blood flow oscillatory patterns in rat pial microvessels during 30 min bilateral common carotid artery occlusion (BCCAO and 60 min reperfusion by laser speckle imaging (LSI. Pial microcirculation was visualized by fluorescence microscopy. The blood flow oscillations of single microvessels were recorded by LSI; spectral analysis was performed by Wavelet transform. Under baseline conditions, arterioles and venules were characterized by blood flow oscillations in the frequency ranges 0.005–0.0095 Hz, 0.0095–0.021 Hz, 0.021–0.052 Hz, 0.052–0.150 Hz and 0.150–0.500 Hz. Arterioles showed oscillations with the highest spectral density when compared with venules. Moreover, the frequency components in the ranges 0.052–0.150 Hz and 0.150–0.500 were predominant in the arteriolar total power spectrum; while, the frequency component in the range 0.150–0.500 Hz showed the highest spectral density in venules. After 30 min BCCAO, the arteriolar spectral density decreased compared to baseline; moreover, the arteriolar frequency component in the range 0.052–0.150 Hz significantly decreased in percent spectral density, while the frequency component in the range 0.150–0.500 Hz significantly increased in percent spectral density. However, an increase in arteriolar spectral density was detected at 60 min reperfusion compared to BCCAO values; consequently, an increase in percent spectral density of the frequency component in the range 0.052–0.150 Hz was observed, while the percent spectral density of the frequency component in the range 0.150–0.500 Hz significantly decreased. The remaining frequency components did not significantly change during hypoperfusion and reperfusion. The changes in blood flow during hypoperfusion/reperfusion caused tissue damage in the cortex and striatum of all animals. In conclusion, our data demonstrate that the frequency component in the range 0.052–0.150 Hz

  6. Mesenchymal stem cells increase antioxidant capacity in intestinal ischemia/reperfusion damage.

    Inan, M; Bakar, E; Cerkezkayabekir, A; Sanal, F; Ulucam, E; Subaşı, C; Karaöz, E

    2017-07-01

    Mesenchymal stem cells (MSCs) may have beneficial effects in reversing intestinal damage resulting from circulatory disorders. The hypothesis of this study is that MSCs increase antioxidant capacity of small bowel tissue following intestinal ischemia reperfusion (I/R) damage. A total of 100 rats were used for the control group and three experimental groups, as follows: the sham control, local MSC, and systemic MSC groups. Each group consisted of 10 animals on days 1, 4, and 7 of the experiment. Ischemia was established by clamping the superior mesenteric artery (SMA) for 45min; following this, reperfusion was carried out for 1, 4, and 7days in all groups. In the local and systemic groups, MSCs were administered intravenously and locally just after the ischemia, and they were investigated after 1, 4, and 7days. The superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (Gpx) activities, as well as malondialdehyde (MDA) and total protein levels, were measured. Histopathological analysis was performed using light and electron microscopy. The indicators of proliferation from the effects of anti- and pro-inflammatory cytokines were evaluated using immunohistochemistry. MDA was increased (Pcytokines interleukin-1β (IL1β), transforming growth factor-β1 (TGFβ1), tumor necrosis factor-α (TNFα), IL6, MIP2, and MPO decreased (Pcytokines EP3 and IL1ra increased (poxygen radicals, suppression of pro-inflammatory cytokines, and increasing the expression of anti-inflammatory cytokines. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. The protective effects of tadalafil on renal damage following ischemia reperfusion injury in rats

    Bulent Erol

    2015-09-01

    Full Text Available Ischemia-reperfusion injury can cause renal damage, and phosphodiesterase inhibitors are reported to regulate antioxidant activity. We investigated the prevention of renal damage using tadalafil after renal ischemia reperfusion (I/R injury in rats. A total of 21 adult male Wistar albino rats were randomly divided into three groups of seven, including Group 1-control, Group 2-I/R, and Group 3-tadalafil + I/R group (I/R-T group received tadalafil intraperitoneally at 30 minutes before ischemia. Inducible nitric oxide synthase, endothelial nitric oxide synthase, malondialdehyde, and total antioxidant capacity levels were evaluated, and histopathological changes and apoptosis in the groups were examined. Tadalafil decreased malondialdehyde levels in the I/R group and increased the total antioxidant capacity level. Histopathological and immunohistochemical findings revealed that tadalafil decreased renal injury scores and the ratios of injured cells, as measured through apoptotic protease activating factor 1, inducible nitric oxide synthase, and endothelial nitric oxide synthase levels. We suggest that tadalafil has protective effects against I/R-related renal tissue injury.

  8. Dexmedetomidine protects from post-myocardial ischaemia reperfusion lung damage in diabetic rats

    Kip, Gülay; Çelik, Ali; Bilge, Mustafa; Alkan, Metin; Kiraz, Hasan Ali; Özer, Abdullah; Şıvgın, Volkan; Erdem, Özlem; Arslan, Mustafa; Kavutçu, Mustafa

    2015-01-01

    Objective Diabetic complications and lipid peroxidation are known to have a close association. Lipid peroxidation commonly occurs at sites exposed to ischaemia, but distant organs and tissues also get damaged during ischaemia/reperfusion (I/R). Some of these targets are vital organs, such as the lung, liver, and kidney; the lung is the most frequently affected. The aim of our study was to investigate the effects of dexmedetomidine on I/R damage in lung tissue and on the oxidant/anti-oxidant system in diabetic rats. Material and methods Diabetes was induced with streptozotocin (55 mg/kg) in 18 Wistar Albino rats, which were then randomly divided into three groups (diabetes control (DC), diabetes plus ischaemia-reperfusion (DIR), and diabetes plus dexmedetomidine-ischaemia/reperfusion (DIRD)) after the effects of diabetes were clearly evident. The rats underwent a left thoracotomy and then ischaemia was produced in the myocardium muscle by a left anterior descending artery ligation for 30 min in the DIR and DIRD groups. I/R was performed for 120 min. The DIRD group received a single intraperitoneal dose of dexmedetomidine (100 µg/kg); the DIR group received no dexmedetomidine. Group DC was evaluated as the diabetic control group and also included six rats (C group) in which diabetes was not induced. These mice underwent only left thoracotomy and were closed without undergoing myocardial ischaemia. Histopathological changes, activities of catalase (CAT) and glutathione-S-transferase anti-oxidant enzymes, and malondialdehyde (MDA) levels were evaluated in the lung tissues of all rats. Results Neutrophil infiltration/aggregation was higher in the DIR group than in the C, DC, and DIRD groups (p=0.001, p=0.013, and p=0.042, respectively). The lung injury score was significantly higher in the DIR group than in the C and DC groups (p<0.0001 and p=0.024, respectively). The levels of MDA were significantly higher in the DIR group than in the C and DIRD groups. CAT activity

  9. Dexmedetomidine protects from post-myocardial ischaemia reperfusion lung damage in diabetic rats

    Gülay Kip

    2015-09-01

    Full Text Available Objective: Diabetic complications and lipid peroxidation are known to have a close association. Lipid peroxidation commonly occurs at sites exposed to ischaemia, but distant organs and tissues also get damaged during ischaemia/reperfusion (I/R. Some of these targets are vital organs, such as the lung, liver, and kidney; the lung is the most frequently affected. The aim of our study was to investigate the effects of dexmedetomidine on I/R damage in lung tissue and on the oxidant/anti-oxidant system in diabetic rats. Material and methods: Diabetes was induced with streptozotocin (55 mg/kg in 18 Wistar Albino rats, which were then randomly divided into three groups (diabetes control (DC, diabetes plus ischaemia-reperfusion (DIR, and diabetes plus dexmedetomidine-ischaemia/reperfusion (DIRD after the effects of diabetes were clearly evident. The rats underwent a left thoracotomy and then ischaemia was produced in the myocardium muscle by a left anterior descending artery ligation for 30 min in the DIR and DIRD groups. I/R was performed for 120 min. The DIRD group received a single intraperitoneal dose of dexmedetomidine (100 µg/kg; the DIR group received no dexmedetomidine. Group DC was evaluated as the diabetic control group and also included six rats (C group in which diabetes was not induced. These mice underwent only left thoracotomy and were closed without undergoing myocardial ischaemia. Histopathological changes, activities of catalase (CAT and glutathione-S-transferase anti-oxidant enzymes, and malondialdehyde (MDA levels were evaluated in the lung tissues of all rats. Results: Neutrophil infiltration/aggregation was higher in the DIR group than in the C, DC, and DIRD groups (p=0.001, p=0.013, and p=0.042, respectively. The lung injury score was significantly higher in the DIR group than in the C and DC groups (p<0.0001 and p=0.024, respectively. The levels of MDA were significantly higher in the DIR group than in the C and DIRD groups. CAT

  10. L-NIL prevents renal microvascular hypoxia and increase of renal oxygen consumption after ischemia-reperfusion in rats

    Legrand, Matthieu; Almac, Emre; Mik, Egbert G.; Johannes, Tanja; Kandil, Asli; Bezemer, Rick; Payen, Didier; Ince, Can

    2009-01-01

    Legrand M, Almac E, Mik EG, Johannes T, Kandil A, Bezemer R, Payen D, Ince C. L-NIL prevents renal microvascular hypoxia and increase of renal oxygen consumption after ischemia-reperfusion in rats. Am J Physiol Renal Physiol 296: F1109-F1117, 2009. First published February 18, 2009;

  11. Hepatic ischemia-reperfusion injury: roles of Ca2+ and other intracellular mediators of impaired bile flow and hepatocyte damage.

    Nieuwenhuijs, Vincent B; De Bruijn, Menno T; Padbury, Robert T A; Barritt, Gregory J

    2006-06-01

    Liver resection and liver transplantation have been successful in the treatment of liver tumors and end-stage liver disease. This success has led to an expansion in the pool of patients potentially treatable by liver surgery and, in the case of transplantation, to a shortage of liver donors. At present, there are significant numbers of potential candidates for liver resection and liver donation who have fatty livers, are aged, or have livers damaged by chemotherapy. All of these are at high risk for ischemic reperfusion (IR) injury. The aims of this review are to assess current knowledge of the clinical effectiveness of ischemic preconditioning and intermittent ischemia in reducing IR damage in liver surgery; to evaluate the use of bile flow as a sensitive indicator of IR liver damage; and to analyze the molecular mechanisms, especially intracellular Ca2+, involved in IR injury and ischemic preconditioning. It is concluded that bile flow is a sensitive indicator of IR injury. Together with reactive oxygen species (ROS) and other extracellular and intracellular signaling molecules, intracellular Ca2+ in hepatocytes plays a key role in the normal regulation of bile flow and in IR-induced injury and cell death. Ischemic preconditioning is an effective strategy to reduce IR injury but there is considerable scope for improvement, especially in patients with fatty and aged livers. The development of effective new strategies to reduce IR injury will depend on improved understanding of the molecular mechanisms involved, especially by gaining a better perspective of the relative importance of the various intrahepatocyte signaling pathways involved.

  12. Hypothermic oxygenated machine perfusion reduces bile duct reperfusion injury after transplantation of donation after circulatory death livers

    van Rijn, Rianne; van Leeuwen, Otto B.; Matton, Alix P. M.; Burlage, Laura C.; Wiersema‐Buist, Janneke; van den Heuvel, Marius C.; de Kleine, Ruben H. J.; de Boer, Marieke T.; Gouw, Annette S. H.

    2018-01-01

    Dual hypothermic oxygenated machine perfusion (DHOPE) of the liver has been advocated as a method to reduce ischemia/reperfusion injury (IRI). This study aimed to determine whether DHOPE reduces IRI of the bile ducts in donation after circulatory death (DCD) liver transplantation. In a recently performed phase 1 trial, 10 DCD livers were preserved with DHOPE after static cold storage (SCS; http://www.trialregister.nl NTR4493). Bile duct biopsies were obtained at the end of SCS (before DHOPE; baseline) and after graft reperfusion in the recipient. Histological severity of biliary injury was graded according to an established semiquantitative grading system. Twenty liver transplantations using DCD livers not preserved with DHOPE served as controls. Baseline characteristics and the degree of bile duct injury at baseline (end of SCS) were similar between both groups. In controls, the degree of stroma necrosis (P = 0.002) and injury of the deep peribiliary glands (PBG; P = 0.02) increased after reperfusion compared with baseline. In contrast, in DHOPE‐preserved livers, the degree of bile duct injury did not increase after reperfusion. Moreover, there was less injury of deep PBG (P = 0.04) after reperfusion in the DHOPE group compared with controls. In conclusion, this study suggests that DHOPE reduces IRI of bile ducts after DCD liver transplantation. Liver Transplantation 24 655–664 2018 AASLD. PMID:29369470

  13. Free Radical Damage in Ischemia-Reperfusion Injury: An Obstacle in Acute Ischemic Stroke after Revascularization Therapy

    Ming-Shuo Sun

    2018-01-01

    Full Text Available Acute ischemic stroke is a common cause of morbidity and mortality worldwide. Thrombolysis with recombinant tissue plasminogen activator and endovascular thrombectomy are the main revascularization therapies for acute ischemic stroke. However, ischemia-reperfusion injury after revascularization therapy can result in worsening outcomes. Among all possible pathological mechanisms of ischemia-reperfusion injury, free radical damage (mainly oxidative/nitrosative stress injury has been found to play a key role in the process. Free radicals lead to protein dysfunction, DNA damage, and lipid peroxidation, resulting in cell death. Additionally, free radical damage has a strong connection with inducing hemorrhagic transformation and cerebral edema, which are the major complications of revascularization therapy, and mainly influencing neurological outcomes due to the disruption of the blood-brain barrier. In order to get a better clinical prognosis, more and more studies focus on the pharmaceutical and nonpharmaceutical neuroprotective therapies against free radical damage. This review discusses the pathological mechanisms of free radicals in ischemia-reperfusion injury and adjunctive neuroprotective therapies combined with revascularization therapy against free radical damage.

  14. Chymase mediates injury and mitochondrial damage in cardiomyocytes during acute ischemia/reperfusion in the dog.

    Zheng, Junying; Wei, Chih-Chang; Hase, Naoki; Shi, Ke; Killingsworth, Cheryl R; Litovsky, Silvio H; Powell, Pamela C; Kobayashi, Tsunefumi; Ferrario, Carlos M; Rab, Andras; Aban, Inmaculada; Collawn, James F; Dell'Italia, Louis J

    2014-01-01

    Cardiac ischemia and reperfusion (I/R) injury occurs because the acute increase in oxidative/inflammatory stress during reperfusion culminates in the death of cardiomyocytes. Currently, there is no drug utilized clinically that attenuates I/R injury in patients. Previous studies have demonstrated degranulation of mast cell contents into the interstitium after I/R. Using a dog model of I/R, we tested the role of chymase, a mast cell protease, in cardiomyocyte injury using a specific oral chymase inhibitor (CI). 15 adult mongrel dogs had left anterior descending artery occlusion for 60 min and reperfusion for 100 minutes. 9 dogs received vehicle and 6 were pretreated with a specific CI. In vivo cardiac microdialysis demonstrated a 3-fold increase in interstitial fluid chymase activity in I/R region that was significantly decreased by CI. CI pretreatment significantly attenuated loss of laminin, focal adhesion complex disruption, and release of troponin I into the circulation. Microarray analysis identified an I/R induced 17-fold increase in nuclear receptor subfamily 4A1 (NR4A1) and significantly decreased by CI. NR4A1 normally resides in the nucleus but can induce cell death on migration to the cytoplasm. I/R caused significant increase in NR4A1 protein expression and cytoplasmic translocation, and mitochondrial degradation, which were decreased by CI. Immunohistochemistry also revealed a high concentration of chymase within cardiomyocytes after I/R. In vitro, chymase added to culture HL-1 cardiomyocytes entered the cytoplasm and nucleus in a dynamin-dependent fashion, and promoted cytoplasmic translocation of NR4A1 protein. shRNA knockdown of NR4A1 on pre-treatment of HL-1 cells with CI significantly decreased chymase-induced cell death and mitochondrial damage. These results suggest that the beneficial effects of an orally active CI during I/R are mediated in the cardiac interstitium as well as within the cardiomyocyte due to a heretofore-unrecognized chymase

  15. Chymase mediates injury and mitochondrial damage in cardiomyocytes during acute ischemia/reperfusion in the dog.

    Junying Zheng

    Full Text Available Cardiac ischemia and reperfusion (I/R injury occurs because the acute increase in oxidative/inflammatory stress during reperfusion culminates in the death of cardiomyocytes. Currently, there is no drug utilized clinically that attenuates I/R injury in patients. Previous studies have demonstrated degranulation of mast cell contents into the interstitium after I/R. Using a dog model of I/R, we tested the role of chymase, a mast cell protease, in cardiomyocyte injury using a specific oral chymase inhibitor (CI. 15 adult mongrel dogs had left anterior descending artery occlusion for 60 min and reperfusion for 100 minutes. 9 dogs received vehicle and 6 were pretreated with a specific CI. In vivo cardiac microdialysis demonstrated a 3-fold increase in interstitial fluid chymase activity in I/R region that was significantly decreased by CI. CI pretreatment significantly attenuated loss of laminin, focal adhesion complex disruption, and release of troponin I into the circulation. Microarray analysis identified an I/R induced 17-fold increase in nuclear receptor subfamily 4A1 (NR4A1 and significantly decreased by CI. NR4A1 normally resides in the nucleus but can induce cell death on migration to the cytoplasm. I/R caused significant increase in NR4A1 protein expression and cytoplasmic translocation, and mitochondrial degradation, which were decreased by CI. Immunohistochemistry also revealed a high concentration of chymase within cardiomyocytes after I/R. In vitro, chymase added to culture HL-1 cardiomyocytes entered the cytoplasm and nucleus in a dynamin-dependent fashion, and promoted cytoplasmic translocation of NR4A1 protein. shRNA knockdown of NR4A1 on pre-treatment of HL-1 cells with CI significantly decreased chymase-induced cell death and mitochondrial damage. These results suggest that the beneficial effects of an orally active CI during I/R are mediated in the cardiac interstitium as well as within the cardiomyocyte due to a heretofore

  16. X-ray phase-contrast tomography of renal ischemia-reperfusion damage.

    Astrid Velroyen

    Full Text Available The aim of the study was to investigate microstructural changes occurring in unilateral renal ischemia-reperfusion injury in a murine animal model using synchrotron radiation.The effects of renal ischemia-reperfusion were investigated in a murine animal model of unilateral ischemia. Kidney samples were harvested on day 18. Grating-Based Phase-Contrast Imaging (GB-PCI of the paraffin-embedded kidney samples was performed at a Synchrotron Radiation Facility (beam energy of 19 keV. To obtain phase information, a two-grating Talbot interferometer was used applying the phase stepping technique. The imaging system provided an effective pixel size of 7.5 µm. The resulting attenuation and differential phase projections were tomographically reconstructed using filtered back-projection. Semi-automated segmentation and volumetry and correlation to histopathology were performed.GB-PCI provided good discrimination of the cortex, outer and inner medulla in non-ischemic control kidneys. Post-ischemic kidneys showed a reduced compartmental differentiation, particularly of the outer stripe of the outer medulla, which could not be differentiated from the inner stripe. Compared to the contralateral kidney, after ischemia a volume loss was detected, while the inner medulla mainly retained its volume (ratio 0.94. Post-ischemic kidneys exhibited severe tissue damage as evidenced by tubular atrophy and dilatation, moderate inflammatory infiltration, loss of brush borders and tubular protein cylinders.In conclusion GB-PCI with synchrotron radiation allows for non-destructive microstructural assessment of parenchymal kidney disease and vessel architecture. If translation to lab-based approaches generates sufficient density resolution, and with a time-optimized image analysis protocol, GB-PCI may ultimately serve as a non-invasive, non-enhanced alternative for imaging of pathological changes of the kidney.

  17. Neuroprotective effects of oxysophocarpine on neonatal rat primary cultured hippocampal neurons injured by oxygen-glucose deprivation and reperfusion.

    Zhu, Qing-Luan; Li, Yu-Xiang; Zhou, Ru; Ma, Ning-Tian; Chang, Ren-Yuan; Wang, Teng-Fei; Zhang, Yi; Chen, Xiao-Ping; Hao, Yin-Ju; Jin, Shao-Ju; Ma, Lin; Du, Juan; Sun, Tao; Yu, Jian-Qiang

    2014-08-01

    Oxysophocarpine (OSC), a quinolizidine alkaloid extracted from leguminous plants of the genus Robinia, is traditionally used for various diseases including neuronal disorders. This study investigated the protective effects of OSC on neonatal rat primary-cultured hippocampal neurons were injured by oxygen-glucose deprivation and reperfusion (OGD/RP). Cultured hippocampal neurons were exposed to OGD for 2 h followed by a 24 h RP. OSC (1, 2, and 5 μmol/L) and nimodipine (Nim) (12 μmol/L) were added to the culture after OGD but before RP. The cultures of the control group were not exposed to OGD/RP. MTT and LDH assay were used to evaluate the protective effects of OSC. The concentration of intracellular-free calcium [Ca(2+)]i and mitochondrial membrane potential (MMP) were determined to evaluate the degree of neuronal damage. Morphologic changes of neurons following OGD/RP were observed with a microscope. The expression of caspase-3 and caspase-12 mRNA was examined by real-time quantitative PCR. The IC50 of OSC was found to be 100 μmol/L. Treatment with OSC (1, 2, and 5 μmol/L) attenuated neuronal damage (p < 0.001), with evidence of increased cell viability (p < 0.001) and decreased cell morphologic impairment. Furthermore, OSC increased MMP (p < 0.001), but it inhibited [Ca(2+)]i (p < 0.001) elevation in a dose-dependent manner at OGD/RP. OSC (5 μmol/L) also decreased the expression of caspase-3 (p < 0.05) and caspase-12 (p < 0.05). The results suggested that OSC has significant neuroprotective effects that can be attributed to inhibiting endoplasmic reticulum (ER) stress-induced apoptosis.

  18. Gadd45b prevents autophagy and apoptosis against rat cerebral neuron oxygen-glucose deprivation/reperfusion injury.

    He, Guoqian; Xu, Wenming; Tong, Linyan; Li, Shuaishuai; Su, Shiceng; Tan, Xiaodan; Li, Changqing

    2016-04-01

    Autophagic (type II) cell death has been suggested to play pathogenetic roles in cerebral ischemia. Growth arrest and DNA damage response 45b (Gadd45b) has been shown to protect against rat brain ischemia injury through inhibiting apoptosis. However, the relationship between Gadd45b and autophagy in cerebral ischemia/reperfusion (I/R) injury remains uncertain. The aim of this study is to investigate the effect of Gadd45b on autophagy. We adopt the oxygen-glucose deprivation and reperfusion (OGD/R) model of rat primary cortex neurons, and lentivirus interference used to silence Gadd45b expression. Cell viability and injury assay were performed using CCK-8 and LDH kit. Autophagy activation was monitored by expression of ATG5, LC3, Beclin-1, ATG7 and ATG3. Neuron apoptosis was monitored by expression of Bcl-2, Bax, cleaved caspase3, p53 and TUNEL assay. Neuron neurites were assayed by double immunofluorescent labeling with Tuj1 and LC3B. Here, we demonstrated that the expression of Gadd45b was strongly up-regulated at 24 h after 3 h OGD treatment. ShRNA-Gadd45b increased the expression of autophagy related proteins, aggravated OGD/R-induced neuron cell apoptosis and neurites injury. ShRNA-Gadd45b co-treatment with autophagy inhibitor 3-methyladenine (3-MA) or Wortmannin partly inhibited the ratio of LC3II/LC3I, and slightly ameliorated neuron cell apoptosis under OGD/R. Furthermore, shRNA-Gadd45b inhibited the p-p38 level involved in autophagy, but increased the p-JNK level involved in apoptosis. ShRNA-Gadd45b co-treatment with p38 inhibitor obviously induced autophagy. ShRNA-Gadd45b co-treatment with JNK inhibitor alleviated neuron cell apoptosis. In conclusion, our data suggested that Gadd45b inhibited autophagy and apoptosis under OGD/R. Gadd45b may be a common regulatory protein to control autophagy and apoptosis.

  19. Rapid reversal of human intestinal ischemia-reperfusion induced damage by shedding of injured enterocytes and reepithelialisation.

    Joep P M Derikx

    Full Text Available BACKGROUND: Intestinal ischemia-reperfusion (IR is a phenomenon related to physiological conditions (e.g. exercise, stress and to pathophysiological events (e.g. acute mesenteric ischemia, aortic surgery. Although intestinal IR has been studied extensively in animals, results remain inconclusive and data on human intestinal IR are scarce. Therefore, an experimental harmless model for human intestinal IR was developed, enabling us to clarify the sequelae of human intestinal IR for the first time. METHODS AND FINDINGS: In 30 patients undergoing pancreatico-duodenectomy we took advantage of the fact that in this procedure a variable length of jejunum is removed. Isolated jejunum (5 cm was subjected to 30 minutes ischemia followed by reperfusion. Intestinal Fatty Acid Binding Protein (I-FABP arteriovenous concentration differences across the bowel segment were measured before and after ischemia to assess epithelial cell damage. Tissue sections were collected after ischemia and at 25, 60 and 120 minutes reperfusion and stained with H&E, and for I-FABP and the apoptosis marker M30. Bonferroni's test was used to compare I-FABP differences. Mean (SEM arteriovenous concentration gradients of I-FABP across the jejunum revealed rapidly developing epithelial cell damage. I-FABP release significantly increased from 290 (46 pg/ml before ischemia towards 3,997 (554 pg/ml immediately after ischemia (p<0.001 and declined gradually to 1,143 (237 pg/ml within 1 hour reperfusion (p<0.001. Directly after ischemia the intestinal epithelial lining was microscopically normal, while subepithelial spaces appeared at the villus tip. However, after 25 minutes reperfusion, enterocyte M30 immunostaining was observed at the villus tip accompanied by shedding of mature enterocytes into the lumen and loss of I-FABP staining. Interestingly, within 60 minutes reperfusion the epithelial barrier resealed, while debris of apoptotic, shedded epithelial cells was observed in the lumen

  20. Oxidative damage following cerebral ischemia depends on reperfusion - a biochemical study in rat

    Nita, D A; Nita, V; Spulber, S

    2002-01-01

    of lipid peroxidation (LPO) and both enzymatic (superoxide dismutase - SOD, catalase - CAT, glutathione peroxidase - GPx) and non-enzymatic antioxidants activity (glutathione - GSH); and second, to try to find out how the pattern of reperfusion may influence the balance between free radical production...

  1. Ameliorating effects of traditional Chinese medicine preparation, Chinese materia medica and active compounds on ischemia/reperfusion-induced cerebral microcirculatory disturbances and neuron damage

    Sun, Kai; Fan, Jingyu; Han, Jingyan

    2015-01-01

    Ischemic stroke and ischemia/reperfusion (I/R) injury induced by thrombolytic therapy are conditions with high mortality and serious long-term physical and cognitive disabilities. They have a major impact on global public health. These disorders are associated with multiple insults to the cerebral microcirculation, including reactive oxygen species (ROS) overproduction, leukocyte adhesion and infiltration, brain blood barrier (BBB) disruption, and capillary hypoperfusion, ultimately resulting in tissue edema, hemorrhage, brain injury and delayed neuron damage. Traditional Chinese medicine (TCM) has been used in China, Korea, Japan and other Asian countries for treatment of a wide range of diseases. In China, the usage of compound TCM preparation to treat cerebrovascular diseases dates back to the Han Dynasty. Even thousands of years earlier, the medical formulary recorded many classical prescriptions for treating cerebral I/R-related diseases. This review summarizes current information and underlying mechanisms regarding the ameliorating effects of compound TCM preparation, Chinese materia medica, and active components on I/R-induced cerebral microcirculatory disturbances, brain injury and neuron damage. PMID:26579420

  2. Estudo da fração inspirada de oxigênio na isquemia-reperfusão pulmonar em ratos Study of ventilation with different inspired oxygen concentration on lung ischaemia-reperfusion injury in rats

    Rafael José Silveira

    2004-10-01

    Full Text Available OBJETIVO: Estudar o efeito das frações inspiradas de oxigênio (FiO2 a 0,21, 0,40 e 1,00 na isquemia-reperfusão pulmonar. MÉTODOS: Foram utilizados 40 ratos Wistar, distribuídos aleatoriamente em quatro grupos. O grupo I foi o controle e, nos grupos II, III e IV, os animais foram ventilados durante a isquemia-reperfusão com FiO2 a 0,21, 0,40 e 1,00 respectivamente. O modelo utilizado foi de isquemia-reperfusão normotérmica, in situ. O tempo de isquemia foi de 30 minutos e o de reperfusão, de 10 minutos. Como parâmetros de avaliação, utilizou-se a pressão arterial média sistêmica (PAM, a relação entre a pressão parcial de oxigênio e a fração inspirada de oxigênio (PO2/FiO2, a dosagem da glutationa reduzida (GSH e das substâncias reativas ao ácido tiobarbitúrico (TBARS no tecido pulmonar e a relação entre o peso pulmonar úmido e o peso pulmonar seco. RESULTADOS: Os resultados mostraram que a ventilação com FiO2 a 0,21, quando comparada à ventilação com FiO2 a 0,40 e 1,00, durante o período de isquemia-reperfusão, apresentou menor diminuição da PAM, melhor relação PO2/FiO2, maior valor na medida da GSH, menor produção das TBARS e menor formação de edema pulmonar. CONCLUSÃO: A ventilação com baixa FiO2 (0,21 mostrou melhores resultados quando comparada àquelas realizadas com FiO2 mais elevadas (0,40 e 1,00 na isquemia-reperfusão pulmonar.PURPOSE: To evaluate the FiO2 effect at 0,21, 0,40 and 1,00 on the lung ischaemia-reperfusion injury. METHODS: Forty Wistar rats were randomly allocated in 4 groups. The group I was the control one, and in groups II, III, IV rats were ventilated during the ischaemia-reperfusion at 0,21, 0,40 and 1.00 FiO2 respectively. The ischaemia time was 30 minutes and the reperfusion time was 10 minutes. The model used was normothermic ischaemia-reperfusion, in situ. As assessment parameters, the systemic average arterial pressure (PAM, the oxygen arterial partial pressure

  3. Label-free electrochemical detection of singlet oxygen protein damage

    Vargová, Veronika; Gimenez, R.E.; Černocká, Hana; Trujillo, D.C.; Tulli, F.; Zanini, V.I.P.; Paleček, Emil; Borsarelli, C.D.; Ostatná, Veronika

    2016-01-01

    Roč. 187, JAN 2016 (2016), s. 662-669 ISSN 0013-4686 R&D Projects: GA ČR GA13-00956S Institutional support: RVO:68081707 Keywords : singlet oxygen protein damage * surface-attached protein stability * mercury and carbon electrodes Subject RIV: BO - Biophysics Impact factor: 4.798, year: 2016

  4. Role of lipoxygenases and the lipoxin A(4)/annexin 1 receptor in ischemia-reperfusion-induced gastric mucosal damage in rats.

    Peskar, Brigitta M; Ehrlich, Karlheinz; Schuligoi, Rufina; Peskar, Bernhard A

    2009-01-01

    Rat gastric mucosal damage was induced by ischemia-reperfusion. The 5-lipoxygenase inhibitors MK886 and A63162, the 12-lipoxygenase inhibitor baicalein, the 15-lipoxygenase inhibitor PD146176 and the lipoxin (LX) A(4)/annexin 1 antagonist Boc1 increased mucosal damage in a dose-dependent manner. Low doses of these compounds, which have no effects on mucosal integrity, cause severe damage when combined with low doses of indomethacin, celecoxib or dexamethasone. 16,16-Dimethylprostaglandin (PG) E(2) and LXA(4) can replace each other in preventing mucosal injury induced by either cyclooxygenase or lipoxygenase inhibitors. The results suggest that not only cyclooxygenases, but also lipoxygenases have a role in limiting gastric mucosal damage during ischemia-reperfusion. Copyright 2009 S. Karger AG, Basel.

  5. Hsp20 Protects against Oxygen-Glucose Deprivation/Reperfusion-Induced Golgi Fragmentation and Apoptosis through Fas/FasL Pathway

    Bingwu Zhong

    2015-01-01

    Full Text Available Cerebral ischemia-reperfusion injury plays an important role in the development of tissue injury after acute ischemic stroke. Finding effective neuroprotective agents has become a priority in the treatment of ischemic stroke. The Golgi apparatus (GA is a pivotal organelle and its protection is an attractive target in the treatment of cerebral ischemia-reperfusion injury. Protective effects of Hsp20, a potential cytoprotective agent due to its chaperone-like activity and involvement in regulation of many vital processes, on GA were assessed in an ischemia-reperfusion injury model. Mouse neuroblastoma Neuro2a (N2a cells were subjected to oxygen-glucose deprivation/reperfusion (OGDR insult. OGDR induces Golgi fragmentation, apoptosis, and p115 cleavage in N2a cells. However, transfection with Hsp20 significantly attenuates OGDR-induced Golgi fragmentation and apoptosis. Hsp20 interacts with Bax, decreases FasL and Bax expression, and inhibits caspases 3 and p115 cleavage in N2a cells exposed to OGDR. Our data demonstrate that increased Hsp20 expression protects against OGDR-induced Golgi fragmentation and apoptosis, likely through interaction with Bax and subsequent amelioration of the OGDR-induced elevation in p115 cleavage via the Fas/FasL signaling pathway. This neuroprotective potential of Hsp20 against OGDR insult and the underlying mechanism will pave the way for its potential clinical application for cerebral ischemia-reperfusion related disorders.

  6. A Conformational Change in C-Reactive Protein Enhances Leukocyte Recruitment and Reactive Oxygen Species Generation in Ischemia/Reperfusion Injury

    Jan R. Thiele

    2018-04-01

    Full Text Available IntroductionC-reactive protein circulates as a pentameric protein (pCRP. pCRP is a well-established diagnostic marker as plasma levels rise in response to tissue injury and inflammation. We recently described pro-inflammatory properties of CRP, which are mediated by conformational changes from pCRP to bioactive isoforms expressing pro-inflammatory neo-epitopes [pCRP* and monomeric C-reactive protein (mCRP]. Here, we investigate the role of CRP isoforms in renal ischemia/reperfusion injury (IRI.MethodsRat kidneys in animals with and without intraperitoneally injected pCRP were subjected to IRI by the time of pCRP exposure and were subsequently analyzed for monocyte infiltration, caspase-3 expression, and tubular damage. Blood urea nitrogen (BUN was analyzed pre-ischemia and post-reperfusion. CRP effects on leukocyte recruitment were investigated via intravital imaging of rat-striated muscle IRI. Localized conformational CRP changes were analyzed by immunohistochemistry using conformation specific antibodies. 1,6-bis(phosphocholine-hexane (1,6-bisPC, which stabilizes CRP in its native pentameric form was used to validate CRP effects. Leukocyte activation was assessed by quantification of reactive oxygen species (ROS induction by CRP isoforms ex vivo and in vitro through electron spin resonance spectroscopy. Signaling pathways were analyzed by disrupting lipid rafts with nystatin and subsequent ROS detection. In order to confirm the translational relevance of our findings, biopsies of microsurgical human free tissue transfers before and after IRI were examined by immunofluorescence for CRP deposition and co-localization of CD68+ leukocytes.ResultsThe application of pCRP aggravates tissue damage in renal IRI. 1,6-bisPC reverses these effects via inhibition of the conformational change that leads to exposure of pro-inflammatory epitopes in CRP (pCRP* and mCRP. Structurally altered CRP induces leukocyte–endothelial interaction and induces ROS

  7. Edaravone prevents lung injury induced by hepatic ischemia-reperfusion.

    Uchiyama, Munehito; Tojo, Kentaro; Yazawa, Takuya; Ota, Shuhei; Goto, Takahisa; Kurahashi, Kiyoyasu

    2015-04-01

    Lung injury is a major clinical concern after hepatic ischemia-reperfusion (I/R), due to the production of reactive oxygen species in the reperfused liver. We investigated the efficacy of edaravone, a potent free-radical scavenger, for attenuating lung injury after hepatic I/R. Adult male Sprague-Dawley rats were assigned to sham + normal saline (NS), I/R + NS, or I/R + edaravone group. Rats in the I/R groups were subjected to 90 min of partial hepatic I/R. Five minutes before reperfusion, 3 mg/kg edaravone was administered to the I/R + edaravone group. After 6 h of reperfusion, we evaluated lung histopathology and wet-to-dry ratio. We also measured malondialdehyde (MDA), an indicator of oxidative stress, in the liver and the lung, as well as cytokine messenger RNA expressions in the reperfused liver and plasma cytokine concentrations. Histopathology revealed lung damages after 6 h reperfusion of partial ischemic liver. Moreover, a significant increase in lung wet-to-dry ratio was observed. MDA concentration increased in the reperfused liver, but not in the lungs. Edaravone administration attenuated the lung injury and the increase of MDA in the reperfused liver. Edaravone also suppressed the reperfusion-induced increase of interleukin-6 messenger RNA expressions in the liver and plasma interleukin-6 concentrations. Edaravone administration before reperfusion of the ischemic liver attenuates oxidative stress in the reperfused liver and the subsequent lung injury. Edaravone may be beneficial for preventing lung injury induced by hepatic I/R. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. [Protective effects of luteolin on neurons against oxygen-glucose deprivation/reperfusion injury via improving Na+/K+ -ATPase activity].

    Fang, Lumei; Zhang, Mingming; Ding, Yuemin; Fang, Yuting; Yao, Chunlei; Zhang, Xiong

    2010-04-01

    Luteolin, a flavone, has considerable neuroprotective effects by its anti-oxidative mechanism. However, it is still unclear whether luteolin can protect neurons against oxygen-glucose deprivation/reperfusion (OGD/R) induced injury. After 2 hours oxygen-glucose deprivation and 24 hours reperfusion treatment in primary cultured hippocampal neurons, the neuron viability, survival rate and apoptosis rate were evaluated by MTT assay, lactate dehydrogenase (LDH) leakage assay and Hoechst staining, respectively. The activity of Na+/K+ -ATPase was examined in cultured neurons or in the hippocampus of SD rats treated by 10 minutes global cerebral ischemia and followed 24 hours reperfusion. Treatment by OGD/R markedly reduced neuronal viability, increased LDH leakage rate and increased apoptosis rate. Application of luteolin (10-100 micromol x L(-1)) during OGD inhibited OGD/R induced neuron injury and apoptosis in a dose-dependent manner. Compared to the control group or OGP/R-treated neurons, the activity of Na+/K+ -ATPase was significantly suppressed in global ischemia/reperfusion group or OGD/R-treated neurons. Application of luteolin during ischemia or OGD preserved the Na+/K+ -ATPase activity. Furthermore, inhibition of Na+/K+ -ATPase with ouabain attenuated the protective effect afforded by luteolin. The data provide the evidence that luteolin has neuroprotective effect against OGD/R induced injury and the protective effect may be associated with its ability to improve Na+/K+ -ATPase activity after OGD/R.

  9. Cleaning of Fire Damaged Watercolor and Textiles Using Atomic Oxygen

    Rutledge, Sharon K.; Banks, Bruce A.; Chichernea, Virgil A.; Haytas, Christy A.

    2000-01-01

    A noncontact technique is described that uses atomic oxygen generated under low pressure in the presence of nitrogen to remove soot from the surface of a test watercolor panel and strips of cotton, wool and silk. The process, which involves surface oxidation, permits control of the amount of surface material removed. The effectiveness of soot removal from test panels of six basic watercolors (alizarin crimson, burnt sienna, lemon yellow, yellow ochre, cerulean blue and ultramarine blue) and strips of colored cotton, wool and silk was measured using reflectance spectroscopy. The atomic oxygen removed soot effectively from the treated areas and enabled partial recovery of charred watercolors. However, overexposure can result in removal of sizing, bleaching, and weakening of the structure. With the proper precautions, atomic oxygen treatment appears to have great potential to salvage heavily smoke damaged artworks which were previously considered unrestorable.

  10. Reno-Cerebral Reflex Activates the Renin-Angiotensin System, Promoting Oxidative Stress and Renal Damage After Ischemia-Reperfusion Injury.

    Cao, Wei; Li, Aiqing; Li, Jiawen; Wu, Chunyi; Cui, Shuang; Zhou, Zhanmei; Liu, Youhua; Wilcox, Christopher S; Hou, Fan Fan

    2017-09-01

    A kidney-brain interaction has been described in acute kidney injury, but the mechanisms are uncertain. Since we recently described a reno-cerebral reflex, we tested the hypothesis that renal ischemia-reperfusion injury (IRI) activates a sympathetic reflex that interlinks the renal and cerebral renin-angiotensin axis to promote oxidative stress and progression of the injury. Bilateral ischemia-reperfusion activated the intrarenal and cerebral, but not the circulating, renin-angiotensin system (RAS), increased sympathetic activity in the kidney and the cerebral sympathetic regulatory regions, and induced brain inflammation and kidney injury. Selective renal afferent denervation with capsaicin or renal denervation significantly attenuated IRI-induced activation of central RAS and brain inflammation. Central blockade of RAS or oxidative stress by intracerebroventricular (ICV) losartan or tempol reduced the renal ischemic injury score by 65% or 58%, respectively, and selective renal afferent denervation or reduction of sympathetic tone by ICV clonidine decreased the score by 42% or 52%, respectively (all p renal damage and dysfunction persisted after controlling blood pressure with hydralazine. This study uncovered a novel reflex pathway between ischemic kidney and the brain that sustains renal oxidative stress and local RAS activation to promote ongoing renal damage. These data suggest that the renal and cerebral renin-angiotensin axes are interlinked by a reno-cerebral sympathetic reflex that is activated by ischemia-reperfusion, which contributes to ischemia-reperfusion-induced brain inflammation and worsening of the acute renal injury. Antioxid. Redox Signal. 27, 415-432.

  11. The mechanism of Intralipid®-mediated cardioprotection complex IV inhibition by the active metabolite, palmitoylcarnitine, generates reactive oxygen species and activates reperfusion injury salvage kinases.

    Phing-How Lou

    Full Text Available Intralipid® administration at reperfusion elicits protection against myocardial ischemia-reperfusion injury. However, the underlying mechanisms are not fully understood.Sprague-Dawley rat hearts were exposed to 15 min of ischemia and 30 min of reperfusion in the absence or presence of Intralipid® 1% administered at the onset of reperfusion. In separate experiments, the reactive oxygen species (ROS scavenger N-(2-mercaptopropionyl-glycine was added either alone or with Intralipid®. Left ventricular work and activation of Akt, STAT3, and ERK1/2 were used to evaluate cardioprotection. ROS production was assessed by measuring the loss of aconitase activity and the release of hydrogen peroxide using Amplex Red. Electron transport chain complex activities and proton leak were measured by high-resolution respirometry in permeabilized cardiac fibers. Titration experiments using the fatty acid intermediates of Intralipid® palmitoyl-, oleoyl- and linoleoylcarnitine served to determine concentration-dependent inhibition of complex IV activity and mitochondrial ROS release.Intralipid® enhanced postischemic recovery and activated Akt and Erk1/2, effects that were abolished by the ROS scavenger N-(2-mercaptopropionylglycine. Palmitoylcarnitine and linoleoylcarnitine, but not oleoylcarnitine concentration-dependently inhibited complex IV. Only palmitoylcarnitine reached high tissue concentrations during early reperfusion and generated significant ROS by complex IV inhibition. Palmitoylcarnitine (1 µM, administered at reperfusion, also fully mimicked Intralipid®-mediated protection in an N-(2-mercaptopropionyl-glycine -dependent manner.Our data describe a new mechanism of postconditioning cardioprotection by the clinically available fat emulsion, Intralipid®. Protection is elicited by the fatty acid intermediate palmitoylcarnitine, and involves inhibition of complex IV, an increase in ROS production and activation of the RISK pathway.

  12. MicroRNA expression data reveals a signature of kidney damage following ischemia reperfusion injury.

    Michael D Shapiro

    Full Text Available Ischemia reperfusion injury (IRI is a leading cause of acute kidney injury, a common problem worldwide associated with significant morbidity and mortality. We have recently examined the role of microRNAs (miRs in renal IRI using expression profiling. Here we conducted mathematical analyses to determine if differential expression of miRs can be used to define a biomarker of renal IRI. Principal component analysis (PCA was combined with spherical geometry to determine whether samples that underwent renal injury as a result of IRI can be distinguished from controls based on alterations in miR expression using our data set consisting of time series measuring 571 miRs. Using PCA, we examined whether changes in miR expression in the kidney following IRI have a distinct direction when compared to controls based on the trajectory of the first three principal components (PCs for our time series. We then used Monte Carlo methods and spherical geometry to assess the statistical significance of these directions. We hypothesized that if IRI and control samples exhibit distinct directions, then miR expression can be used as a biomarker of injury. Our data reveal that the pattern of miR expression in the kidney following IRI has a distinct direction based on the trajectory of the first three PCs and can be distinguished from changes observed in sham controls. Analyses of samples from immunodeficient mice indicated that the changes in miR expression observed following IRI were lymphocyte independent, and therefore represent a kidney intrinsic response to injury. Together, these data strongly support the notion that IRI results in distinct changes in miR expression that can be used as a biomarker of injury.

  13. Propofol prevents autophagic cell death following oxygen and glucose deprivation in PC12 cells and cerebral ischemia-reperfusion injury in rats.

    Derong Cui

    Full Text Available Propofol exerts protective effects on neuronal cells, in part through the inhibition of programmed cell death. Autophagic cell death is a type of programmed cell death that plays elusive roles in controlling neuronal damage and metabolic homeostasis. We therefore studied whether propofol could attenuate the formation of autophagosomes, and if so, whether the inhibition of autophagic cell death mediates the neuroprotective effects observed with propofol.The cell model was established by depriving the cells of oxygen and glucose (OGD for 6 hours, and the rat model of ischemia was introduced by a transient two-vessel occlusion for 10 minutes. Transmission electron microscopy (TEM revealed that the formation of autophagosomes and autolysosomes in both neuronal PC12 cells and pyramidal rat hippocampal neurons after respective OGD and ischemia/reperfusion (I/R insults. A western blot analysis revealed that the autophagy-related proteins, such as microtubule-associated protein 1 light chain 3 (LC3-II, Beclin-1 and class III PI3K, were also increased accordingly, but cytoprotective Bcl-2 protein was decreased. The negative effects of OGD and I/R, including the formation of autophagosomes and autolysosomes, the increase in LC3-II, Beclin-1 and class III PI3K expression and the decline in Bcl-2 production were all inhibited by propofol and specific inhibitors of autophagy, such as 3-methyladenine (3-MA, LY294002 and Bafilomycin A1 (Baf,. Furthermore, in vitro OGD cultures and in vivo I/R rats showed an increase in cell survival following the administration of propofol, as assessed by an MTT assay or histochemical analyses.Our data suggest that propofol can markedly attenuate autophagic processes via the decreased expression of autophagy-related proteins in vitro and in vivo. This inhibition improves cell survival, which provides a novel explanation for the pleiotropic effects of propofol that benefit the nervous system.

  14. RP105 Protects Against Apoptosis in Ischemia/Reperfusion-Induced Myocardial Damage in Rats by Suppressing TLR4-Mediated Signaling Pathways

    Jun Yang

    2015-07-01

    Full Text Available Background: Myocardial apoptosis is heavily implicated in the myocardial damage caused by ischemia-reperfusion (I/R. Toll-like receptor 4 (TLR4 is a potent inducer of these apoptotic cascades. In contrast, the radioprotective 105 kDa protein (RP105 is a specific negative regulator of TLR4 signaling pathways. However, the precise mechanisms by which RP105 inhibits myocardium apoptosis via TLR4-associated pathways during I/R is not fully understood. Methods: We utilized a rat model of myocardial ischemic reperfusion injury (MIRI. Animals were pre-treated with Ad-EGFP adenovirus, Ad-EGFP-RP105 adenovirus, saline, or nothing (sham. After three days, rats underwent a 30min left anterior descending coronary artery occlusion and a 4h reperfusion. Mycardial tissue was assessed by immunohistochemistry, TUNEL-staining, Western blot, quantitative RT-PCR, and a morphometric assay. Results: RP105 overexpression resulted in a reduction in infarct size, fewer TUNEL-positive cardiomyocytes, and a reduction in mitochondrial-associated apoptosis cascade activity. Further, RP105 overexpression repressed I/R-induced myocardial injury by attenuating myocardial apoptosis. This was mediated by inhibiting TLR4 activation and the phosphorylation of P38MAPK and the downstream transcription factor AP-1. Conclusion: RP105 overexpression leads to the de-activation of TLR4, P38MAPK, and AP-1 signaling pathways, and subsequently represses apoptotic cascades and ensuing damage of myocardial ischemic reperfusion. These findings may become the basis of a novel therapeutic approach for reducing of cardiac damage caused by MIRI.

  15. Involvement of Rho-kinase in cold ischemia-reperfusion injury after liver transplantation in rats.

    Shiotani, Satoko; Shimada, Mitsuo; Suehiro, Taketoshi; Soejima, Yuji; Yosizumi, Tomoharu; Shimokawa, Hiroaki; Maehara, Yoshihiko

    2004-08-15

    Reperfusion of ischemic tissues is known to cause the generation of reactive oxygen species (ROS) with resultant tissue damage. However, the sources of ROS in reperfused tissues are not fully characterized. We hypothesized that the small GTPase Rho and its target effector Rho-kinase/ROK/ROCK are involved in the oxidative burst in reperfused tissue with resultant reperfusion injury. In an in vivo rat model of liver transplantation using cold ischemia for 12 hr followed by reperfusion, a specific Rho-kinase inhibitor, fasudil (30 mg/kg), was administered orally 1 hr before the transplantation. Fasudil suppressed the ischemia-reperfusion (I/R)-induced generation of ROS after reperfusion (P<0.01) and also suppressed the release of inflammatory cytokines (tumor necrosis factor-alpha, interleukin-1beta) 3 hr after reperfusion, resulting in a significant reduction of I/R-induced hepatocellular injury (P<0.05), necrosis, apoptosis (P<0.01), and neutrophil infiltration (P<0.0001) 12 hr after reperfusion. All animals receiving a graft without fasudil died within 3 days, whereas 40% of those receiving fasudil survived (P<0.001). The present study demonstrates that Rho-kinase-mediated production of ROS and inflammatory cytokines are substantially involved in the pathogenesis of hepatocellular necrosis and apoptosis induced by cold I/R in vivo and that Rho-kinase may be regarded as a novel therapeutic target for the disorder.

  16. 17β-Estradiol prevents cell death and mitochondrial dysfunction by estrogen receptor-dependent mechanism in astrocytes following oxygen-glucose deprivation/reperfusion

    Guo, Jiabin; Duckles, Sue P.; Weiss, John H.; Li, Xuejun; Krause, Diana N.

    2012-01-01

    17β-estradiol (E2) has been shown to protect against ischemic brain injury, yet its targets and the mechanisms are unclear. E2 may exert multiple regulatory actions on astrocytes that may greatly contribute to its ability to protect the brain. Mitochondria are recognized to play central roles in the development of injury during ischemia. Increasing evidence indicates that mitochondrial mechanisms are critically involved in E2-mediated protection. In this study, the effect of E2 and the role of mitochondria were evaluated in primary cultures of astrocytes subjected to an ischemia-like condition of oxygen-glucose deprivation (OGD)/reperfusion. We showed that E2 treatment significantly protects against OGD/reperfusion-induced cell death as determined by cell viability, apoptosis and lactate dehydrogenase leakage. The protective effects of E2 on astrocytic survival were blocked by an estrogen receptor (ER) antagonist (ICI 182,780), and were mimicked by an estrogen receptor (ER) agonist selective for ERα (PPT), but not by an ER agonist selective for ERβ (DPN). OGD/reperfusion provoked mitochondria dysfunction as manifested by an increase of cellular reactive oxygen species production, loss of mitochondrial membrane potential and depletion of ATP. E2 pretreatment significantly inhibited OGD/reperfusion-induced mitochondrial dysfunction, and this effect was also blocked by ICI 182,780. Therefore, we concluded that E2 provides direct protection to astrocytes from ischemic injury by an ER-dependent mechanism, highlighting an important role for ERα. Estrogen protects against mitochondria dysfunction at the early phase of ischemic injury. However, overall implications for protection against brain ischemia and its complex sequelae await further exploration. PMID:22554613

  17. 17β-Estradiol prevents cell death and mitochondrial dysfunction by an estrogen receptor-dependent mechanism in astrocytes after oxygen-glucose deprivation/reperfusion.

    Guo, Jiabin; Duckles, Sue P; Weiss, John H; Li, Xuejun; Krause, Diana N

    17β-Estradiol (E2) has been shown to protect against ischemic brain injury, yet its targets and the mechanisms are unclear. E2 may exert multiple regulatory actions on astrocytes that may greatly contribute to its ability to protect the brain. Mitochondria are recognized as playing central roles in the development of injury during ischemia. Increasing evidence indicates that mitochondrial mechanisms are critically involved in E2-mediated protection. In this study, the effects of E2 and the role of mitochondria were evaluated in primary cultures of astrocytes subjected to an ischemia-like condition of oxygen-glucose deprivation (OGD)/reperfusion. We showed that E2 treatment significantly protects against OGD/reperfusion-induced cell death as determined by cell viability, apoptosis, and lactate dehydrogenase leakage. The protective effects of E2 on astrocytic survival were blocked by an estrogen receptor (ER) antagonist (ICI-182,780) and were mimicked by an ER agonist selective for ERα (PPT), but not by an ER agonist selective for ERβ (DPN). OGD/reperfusion provoked mitochondrial dysfunction as manifested by an increase in cellular reactive oxygen species production, loss of mitochondrial membrane potential, and depletion of ATP. E2 pretreatment significantly inhibited OGD/reperfusion-induced mitochondrial dysfunction, and this effect was also blocked by ICI-182,780. Therefore, we conclude that E2 provides direct protection to astrocytes from ischemic injury by an ER-dependent mechanism, highlighting an important role for ERα. Estrogen protects against mitochondrial dysfunction at the early phase of ischemic injury. However, overall implications for protection against brain ischemia and its complex sequelae await further exploration. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. Sympathetic nerve damage and restoration after ischemia-reperfusion injury as assessed by {sup 11}C-hydroxyephedrine

    Werner, Rudolf A.; Higuchi, Takahiro [University of Wuerzburg, Department of Nuclear Medicine, Wuerzburg (Germany); University of Wuerzburg, Comprehensive Heart Failure Center, Wuerzburg (Germany); Maya, Yoshifumi [University of Wuerzburg, Department of Nuclear Medicine, Wuerzburg (Germany); Nihon Medi-Physics Co., Ltd., Research Centre, Chiba (Japan); Rischpler, Christoph [Technische Universitaet Muenchen, Department of Nuclear Medicine, Klinikum rechts der Isar, Muenchen (Germany); Javadi, Mehrbod S. [Johns Hopkins University, Division of Nuclear Medicine, Russell H. Morgan Department of Radiology, Baltimore, MD (United States); Fukushima, Kazuhito [Hyogo College of Medicine, Department of Radiology, Hyogo (Japan); Lapa, Constantin [University of Wuerzburg, Department of Nuclear Medicine, Wuerzburg (Germany); Herrmann, Ken [University of Wuerzburg, Department of Nuclear Medicine, Wuerzburg (Germany); David Geffen School of Medicine at UCLA, Department of Molecular and Medical Pharmacology, Los Angeles, CA (United States)

    2016-02-15

    An altered state of the cardiac sympathetic nerves is an important prognostic factor in patients with coronary artery disease. The aim of this study was to investigate regional sympathetic nerve damage and restoration utilizing a rat model of myocardial transient ischemia and a catecholamine analog PET tracer, {sup 11}C-hydroxyephedrine ({sup 11}C-HED). Transient myocardial ischemia was induced by coronary occlusion for 20 min and reperfusion in male Wistar rats. Dual-tracer autoradiography was performed subacutely (7 days) and chronically (2 months) after ischemia, and in control rats without ischemia using {sup 11}C-HED as a marker of sympathetic innervation and {sup 201}TI for perfusion. Additional serial in vivo cardiac {sup 11}C-HED and {sup 18}F-FDG PET scans were performed in the subacute and chronic phases after ischemia. After transient ischemia, the {sup 11}C-HED uptake defect areas in both the subacute and chronic phases were clearly larger than the perfusion defect areas in the midventricular wall. The subacute {sup 11}C-HED uptake defect showed a transmural pattern, whereas uptake recovered in the subepicardial portion in the chronic phase. Tyrosine hydroxylase antibody nerve staining confirmed regional denervation corresponding to areas of decreased {sup 11}C-HED uptake. Serial in vivo PET imaging visualized reductions in the area of the {sup 11}C-HED uptake defects in the chronic phase consistent with autoradiography and histology. Higher susceptibility of sympathetic neurons compared to myocytes was confirmed by a larger {sup 11}C-HED defect with a corresponding histologically identified region of denervation. Furthermore, partial reinnervation was observed in the chronic phase as shown by recovery of subepicardial {sup 11}C-HED uptake. (orig.)

  19. Review on herbal medicine on brain ischemia and reperfusion

    Nahid Jivad

    2015-10-01

    Cerebral ischemia and reperfusion is known to induce the generation of reactive oxygen species that can lead to oxidative damage of proteins, membrane lipids and nucleic acids. A decrease in tissue antioxidant capacity, an increase in lipid peroxidation as well as an increase in lipid peroxidation inhibitors have been demonstrated in several models of brain ischemia. This paper reviews the number of commonly used types of herbal medicines effective for the treatment of stroke. The aim of this paper was to review evidences from controlled studies in order to discuss whether herbal medicine can be helpful in the treatment of brain ischemia and reperfusion.

  20. The role of platelet factor 4 in local and remote tissue damage in a mouse model of mesenteric ischemia/reperfusion injury.

    Peter H Lapchak

    Full Text Available The robust inflammatory response that occurs during ischemia reperfusion (IR injury recruits factors from both the innate and adaptive immune systems. However the contribution of platelets and their products such as Platelet Factor 4 (PF4; CXCL4, during the pathogenesis of IR injury has not been thoroughly investigated. We show that a deficiency in PF4 protects mice from local and remote tissue damage after 30 minutes of mesenteric ischemia and 3 hours of reperfusion in PF4-/- mice compared to control B6 mice. This protection was independent from Ig or complement deposition in the tissues. However, neutrophil and monocyte infiltration were decreased in the lungs of PF4-/- mice compared with B6 control mice. Platelet-depleted B6 mice transfused with platelets from PF4-/- mice displayed reduced tissue damage compared with controls. In contrast, transfusion of B6 platelets into platelet depleted PF4-/- mice reconstituted damage in both intestine and lung tissues. We also show that PF4 may modulate the release of IgA. Interestingly, we show that PF4 expression on intestinal epithelial cells is increased after IR at both the mRNA and protein levels. In conclusion, these findings demonstrate that may PF4 represent an important mediator of local and remote tissue damage.

  1. Label-free electrochemical detection of singlet oxygen protein damage

    Vargová, Veronika; Giménez, Rodrigo E.; Černocká, Hana; Trujillo, Diana Chito; Tulli, Fiorella; Zanini, Verónica I. Paz; Paleček, Emil; Borsarelli, Claudio D.; Ostatná, Veronika

    2016-01-01

    Oxidative damage of proteins results in changes of their structures and functions. In this work, the singlet oxygen ( 1 O 2 )-mediated oxidation of bovine serum albumin (BSA) and urease by blue-light photosensitization of the tris(2,2′-bipyridine)ruthenium(II) cation [Ru(bpy) 3 ] 2+ was studied by square wave voltammetry at glassy carbon electrode and by constant current chronopotentiometry at mercury electrode. Small changes in voltammetric oxidation Tyr and Trp peaks did not indicate significant changes in the BSA structure after photo-oxidation at carbon electrode. On the other hand chronopotentiometric peak H of BSA at HMDE increased during blue-light photosensitization, indicating that photo-oxidized BSA was more susceptible to the electric field-induced denaturation than non-oxidized native BSA. Similar results were obtained for urease, where enzymatic activity was also evaluated. The present results show the capability of label- and reagent-free electrochemical methods to detect oxidative changes in proteins. We believe that these methods will become important tools for detection of various protein damages.

  2. Renal transplantation induces mitochondrial uncoupling, increased kidney oxygen consumption, and decreased kidney oxygen tension

    Papazova, Diana A.; Friederich-Persson, Malou; Joles, Jaap A.; Verhaar, Marianne C.

    2015-01-01

    Hypoxia is an acknowledged pathway to renal injury and ischemia-reperfusion (I/R) and is known to reduce renal oxygen tension (PO2). We hypothesized that renal I/R increases oxidative damage and induces mitochondrial uncoupling, resulting in increased oxygen consumption and hence kidney

  3. Real-time monitoring of nitric oxide (NO) and pO2 levels under ischemic conditions associated with small bowel ischemia/reperfusion injury using selective electrodes for NO and oxygen molecules.

    Watanabe, T; Owada, S; Kobayashi, H; Ishiuchi, A; Nakano, H; Asakuta, T; Shimamura, T; Asano, T; Koizumi, S; Jinnouchi, Y; Katayama, M; Kamibayasi, M; Murakami, E; Otsubo, T

    2007-12-01

    The present study demonstrated the feasibility of monitoring nitric oxide (NO) and pO2 levels under ischemic conditions associated with small bowel ischemia/reperfusion (I/R) injury through the use of selective electrodes for NO and oxygen molecules. NO levels gradually increased during ischemia. When reperfusion was started, the NO level decreased suddenly and returned to pre-ischemia values within 10 minutes. After clamping, pO2 decreased rapidly. When reperfusion was started, pO2 increased suddenly, returning to pre-ischemia values within 10 minutes. We concluded that it is feasible to monitor NO and pO2 levels under ischemic conditions of small bowel I/R injury through the use of electrodes selective for NO and oxygen molecules.

  4. Passive targeting of lipid-based nanoparticles to mouse cardiac ischemia-reperfusion injury

    Geelen, T.; Paulis, L.E.M.; Coolen, B.F.; Nicolay, K.; Strijkers, G.J.

    2013-01-01

    Reperfusion therapy is commonly applied after a myocardial infarction. Reperfusion, however, causes secondary damage. An emerging approach for treatment of ischemia-reperfusion (IR) injury involves the delivery of therapeutic nanoparticles to the myocardium to promote cell survival and

  5. Oxidative Stress and Lung Ischemia-Reperfusion Injury

    Renata Salatti Ferrari

    2015-01-01

    Full Text Available Ischemia-reperfusion (IR injury is directly related to the formation of reactive oxygen species (ROS, endothelial cell injury, increased vascular permeability, and the activation of neutrophils and platelets, cytokines, and the complement system. Several studies have confirmed the destructiveness of the toxic oxygen metabolites produced and their role in the pathophysiology of different processes, such as oxygen poisoning, inflammation, and ischemic injury. Due to the different degrees of tissue damage resulting from the process of ischemia and subsequent reperfusion, several studies in animal models have focused on the prevention of IR injury and methods of lung protection. Lung IR injury has clinical relevance in the setting of lung transplantation and cardiopulmonary bypass, for which the consequences of IR injury may be devastating in critically ill patients.

  6. High-Dose Polymerized Hemoglobin Fails to Alleviate Cardiac Ischemia/Reperfusion Injury due to Induction of Oxidative Damage in Coronary Artery.

    Yang, Qian; Wu, Wei; Li, Qian; Chen, Chan; Zhou, Ronghua; Qiu, Yanhua; Luo, Ming; Tan, Zhaoxia; Li, Shen; Chen, Gang; Zhou, Wentao; Liu, Jiaxin; Yang, Chengmin; Liu, Jin; Li, Tao

    2015-01-01

    Objective. Ischemia/reperfusion (I/R) injury is an unavoidable event for patients in cardiac surgery under cardiopulmonary bypass (CPB). This study was designed to investigate whether glutaraldehyde-polymerized human placenta hemoglobin (PolyPHb), a hemoglobin-based oxygen carrier (HBOC), can protect heart against CPB-induced I/R injury or not and to elucidate the underlying mechanism. Methods and Results. A standard dog CPB model with 2-hour cardiac arrest and 2-hour reperfusion was established. The results demonstrated that a low-dose PolyPHb (0.1%, w/v) provided a significant protection on the I/R heart, whereas the high-dose PolyPHb (3%, w/v) did not exhibit cardioprotective effect, as evidenced by the impaired cardiac function, decreased myocardial oxygen utilization, and elevated enzymes release and pathological changes. Further study indicated that exposure of isolated coronary arteries or human umbilical vein endothelial cells (HUVECs) to a high-dose PolyPHb caused impaired endothelium-dependent relaxation, which was companied with increased reactive oxygen species (ROS) production, reduced superoxide dismutase (SOD) activity, and elevated malonaldehyde (MDA) formation. Consistent with the increased oxidative stress, the NAD(P)H oxidase activity and subunits expression, including gp91(phox), p47(phox), p67(phox), and Nox1, were greatly upregulated. Conclusion. The high-dose PolyPHb fails to protect heart from CPB-induced I/R injury, which was due to overproduction of NAD(P)H oxidase-induced ROS and resultant endothelial dysfunction.

  7. High-Dose Polymerized Hemoglobin Fails to Alleviate Cardiac Ischemia/Reperfusion Injury due to Induction of Oxidative Damage in Coronary Artery

    Qian Yang

    2015-01-01

    Full Text Available Objective. Ischemia/reperfusion (I/R injury is an unavoidable event for patients in cardiac surgery under cardiopulmonary bypass (CPB. This study was designed to investigate whether glutaraldehyde-polymerized human placenta hemoglobin (PolyPHb, a hemoglobin-based oxygen carrier (HBOC, can protect heart against CPB-induced I/R injury or not and to elucidate the underlying mechanism. Methods and Results. A standard dog CPB model with 2-hour cardiac arrest and 2-hour reperfusion was established. The results demonstrated that a low-dose PolyPHb (0.1%, w/v provided a significant protection on the I/R heart, whereas the high-dose PolyPHb (3%, w/v did not exhibit cardioprotective effect, as evidenced by the impaired cardiac function, decreased myocardial oxygen utilization, and elevated enzymes release and pathological changes. Further study indicated that exposure of isolated coronary arteries or human umbilical vein endothelial cells (HUVECs to a high-dose PolyPHb caused impaired endothelium-dependent relaxation, which was companied with increased reactive oxygen species (ROS production, reduced superoxide dismutase (SOD activity, and elevated malonaldehyde (MDA formation. Consistent with the increased oxidative stress, the NAD(PH oxidase activity and subunits expression, including gp91phox, p47phox, p67phox, and Nox1, were greatly upregulated. Conclusion. The high-dose PolyPHb fails to protect heart from CPB-induced I/R injury, which was due to overproduction of NAD(PH oxidase-induced ROS and resultant endothelial dysfunction.

  8. Mild hypothermia protects hippocampal neurons against oxygen-glucose deprivation/reperfusion-induced injury by improving lysosomal function and autophagic flux.

    Zhou, Tianen; Liang, Lian; Liang, Yanran; Yu, Tao; Zeng, Chaotao; Jiang, Longyuan

    2017-09-15

    Mild hypothermia has been proven to be useful to treat brain ischemia/reperfusion injury. However, the underlying mechanisms have not yet been fully elucidated. The present study was undertaken to determine whether mild hypothermia protects hippocampal neurons against oxygen-glucose deprivation/reperfusion(OGD/R)-induced injury via improving lysosomal function and autophagic flux. The results showed that OGD/R induced the occurrence of autophagy, while the acidic environment inside the lysosomes was altered. The autophagic flux assay with RFP-GFP tf-LC3 was impeded in hippocampal neurons after OGD/R. Mild hypothermia recovered the lysosomal acidic fluorescence and the lysosomal marker protein expression of LAMP2, which decreased after OGD/R.Furthermore, we found that mild hypothermia up-regulated autophagic flux and promoted the fusion of autophagosomes and lysosomes in hippocampal neurons following OGD/R injury, but could be reversed by treatment with chloroquine, which acts as a lysosome inhibitor. We also found that mild hypothermia improved mitochondrial autophagy in hippocampal neurons following OGD/R injury. Finally,we found that chloroquine blocked the protective effects of mild hypothermia against OGD/R-induced cell death and injury. Taken together, the present study indicates that mild hypothermia protects hippocampal neurons against OGD/R-induced injury by improving lysosomal function and autophagic flux. Copyright © 2017. Published by Elsevier Inc.

  9. The Effects of α-Lipoic Acid against Testicular Ischemia-Reperfusion Injury in Rats

    Seda Ozbal

    2012-01-01

    Full Text Available Testicular torsion is one of the urologic emergencies occurring frequently in neonatal and adolescent period. Testis is sensitive to ischemia-reperfusion injury, and, therefore, ischemia and consecutive reperfusion cause an enhanced formation of reactive oxygen species that result in testicular cell damage and apoptosis. α-lipoic acid is a free radical scavenger and a biological antioxidant. It is widely used in the prevention of oxidative stress and cellular damage. We aimed to investigate the protective effect of α-lipoic acid on testicular damage in rats subjected to testicular ischemia-reperfusion injury. 35 rats were randomly divided into 5 groups: control, sham operated, ischemia, ischemia-reperfusion, and ischemia-reperfusion +lipoic acid groups, 2 h torsion and 2 h detorsion of the testis were performed. Testicular cell damage was examined by H-E staining. TUNEL and active caspase-3 immunostaining were used to detect germ cell apoptosis. GPx , SOD activity, and MDA levels were evaluated. Histological evaluation showed that α-lipoic acid pretreatment reduced testicular cell damage and decreased TUNEL and caspase-3-positive cells. Additionally, α-lipoic acid administration decreased the GPx and SOD activity and increased the MDA levels. The present results suggest that LA is a potentially beneficial agent in protecting testicular I/R in rats.

  10. Singlet oxygen-mediated damage to proteins and its consequences

    Davies, Michael Jonathan

    2003-01-01

    by the transfer of energy to ground state (triplet) molecular oxygen by either protein-bound, or other, chromophores. Singlet oxygen can also be generated by a range of other enzymatic and non-enzymatic reactions including processes mediated by heme proteins, lipoxygenases, and activated leukocytes, as well...... the absorption of UV radiation by the protein, or bound chromophore groups, thereby generating excited states (singlet or triplets) or radicals via photo-ionisation. The second major process involves indirect oxidation of the protein via the formation and subsequent reactions of singlet oxygen generated...... as radical termination reactions. This paper reviews the data available on singlet oxygen-mediated protein oxidation and concentrates primarily on the mechanisms by which this excited state species brings about changes to both the side-chains and backbone of amino acids, peptides, and proteins. Recent work...

  11. Antioxidant Action of Mangrove Polyphenols against Gastric Damage Induced by Absolute Ethanol and Ischemia-Reperfusion in the Rat

    Felipe Meira de-Faria

    2012-01-01

    Full Text Available 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 adittion, 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.

  12. Oxygen-charged HTK-F6H8 emulsion reduces ischemia-reperfusion injury in kidneys from brain-dead pigs.

    Asif, Sana; Sedigh, Amir; Nordström, Johan; Brandhorst, Heide; Jorns, Carl; Lorant, Tomas; Larsson, Erik; Magnusson, Peetra U; Nowak, Greg; Theisinger, Sonja; Hoeger, Simone; Wennberg, Lars; Korsgren, Olle; Brandhorst, Daniel

    2012-12-01

    Prolonged cold ischemia is frequently associated with a greater risk of delayed graft function and enhanced graft failure. We hypothesized that media, combining a high oxygen-dissolving capacity with specific qualities of organ preservation solutions, would be more efficient in reducing immediate ischemia-reperfusion injury from organs stored long term compared with standard preservation media. Kidneys retrieved from brain-dead pigs were flushed using either cold histidine-tryptophan-ketoglutarate (HTK) or oxygen-precharged emulsion composed of 75% HTK and 25% perfluorohexyloctane. After 18 h of cold ischemia the kidneys were transplanted into allogeneic recipients and assessed for adenosine triphosphate content, morphology, and expression of genes related to hypoxia, environmental stress, inflammation, and apoptosis. Compared with HTK-flushed kidneys, organs preserved using oxygen-precharged HTK-perfluorohexyloctane emulsion had increased elevated adenosine triphosphate content and a significantly lower gene expression of hypoxia inducible factor-1α, vascular endothelial growth factor, interleukin-1α, tumor necrosis factor-α, interferon-α, JNK-1, p38, cytochrome-c, Bax, caspase-8, and caspase-3 at all time points assessed. In contrast, the mRNA expression of Bcl-2 was significantly increased. The present study has demonstrated that in brain-dead pigs the perfusion of kidneys with oxygen-precharged HTK-perfluorohexyloctane emulsion results in significantly reduced inflammation, hypoxic injury, and apoptosis and cellular integrity and energy content are well maintained. Histologic examination revealed less tubular, vascular, and glomerular changes in the emulsion-perfused tissue compared with the HTK-perfused counterparts. The concept of perfusing organs with oxygen-precharged emulsion based on organ preservation media represents an efficient alternative for improved organ preservation. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Mathematical Modeling of Ischemia-Reperfusion Injury and Postconditioning Therapy.

    Fong, D; Cummings, L J

    2017-11-01

    Reperfusion (restoration of blood flow) after a period of ischemia (interruption of blood flow) can paradoxically place tissues at risk of further injury: so-called ischemia-reperfusion injury or IR injury. Recent studies have shown that postconditioning (intermittent periods of further ischemia applied during reperfusion) can reduce IR injury. We develop a mathematical model to describe the reperfusion and postconditioning process following an ischemic insult, treating the blood vessel as a two-dimensional channel, lined with a monolayer of endothelial cells that interact (respiration and mechanotransduction) with the blood flow. We investigate how postconditioning affects the total cell density within the endothelial layer, by varying the frequency of the pulsatile flow and the oxygen concentration at the inflow boundary. We find that, in the scenarios we consider, the pulsatile flow should be of high frequency to minimize cellular damage, while oxygen concentration at the inflow boundary should be held constant, or subject to only low-frequency variations, to maximize cell proliferation.

  14. Utility of Cardiac Magnetic Resonance to assess association between admission hyperglycemia and myocardial damage in patients with reperfused ST-Segment Elevation Myocardial Infarction

    Wolf Jean-Eric

    2008-01-01

    Full Text Available Abstract Aims to investigate the association between admission hyperglycemia and myocardial damage in patients with ST-segment elevation myocardial infarction (STEMI using Cardiac Magnetic Resonance (CMR. Methods We analyzed 113 patients with STEMI treated with successful primary percutaneous coronary intervention. Admission hyperglycemia was defined as a glucose level ≥ 7.8 mmol/l. Contrast-enhanced CMR was performed between 3 and 7 days after reperfusion to evaluate left ventricular function and perfusion data after injection of gadolinium-DTPA. First-pass images (FP, providing assessment of microvascular obstruction and Late Gadolinium Enhanced images (DE, reflecting the extent of infarction, were investigated and the extent of transmural tissue damage was determined by visual scores. Results Patients with a supramedian FP and DE scores more frequently had left anterior descending culprit artery (p = 0.02 and 1c (p = 0.01 and 0.04, peak plasma Creatine Kinase (p In a multivariate model, admission hyperglycemia remains independently associated with increased FP and DE scores. Conclusion Our results show the existence of a strong relationship between glucose metabolism impairment and myocardial damage in patients with STEMI. Further studies are needed to show if aggressive glucose control improves myocardial perfusion, which could be assessed using CMR.

  15. Peculiarities of reaction of HIF-1α protein of the hippocampus neurons in rats with experimental diabetes mellitus in the dynamics of ischemic-reperfusion damage of the brain

    T. M. Boychuk

    2016-12-01

    Higher State Educational Establishment of Ukraine “Bukovinian State medical University”, Chernivtsi, Ukraine   Abstract Introduction. The role of the transcriptional factor Hif-1α in pathogenesis of hypoxic damages and diabetes mellitus (DM is proved, although molecular mechanisms underlying the basis of this factor dysfunction in association with DM with ischemic-reperfusion damage of the brain remain unknown. Objective. The objective of this investigation was to study the content of Hif-1α protein in the hippocampus neurons of rats with experimental DM in the dynamics of ischemic-reperfusion damage of the brain. Results. In rats without DM 20 minute ischemia with one hour reperfusion increases the content of Hif-1α protein in all the fields of the hippocampus. On the 12th day of ischemic-reperfusion period in the hippocampus CA2-CA4 fields the values of certain examined indices of the activity of Hif-1α transcriptional factor continue to increase, and in СА1field they normalize or approach to the values of animals in the control group.  In rats with DM during early post-ischemic period there are no changes of Hif-1α protein content in CA1 field, in CA2 field there are signs of its reduced activity, in CA3 field they are limited by the reaction of one index, in CA4 field they are of a similar character with those of the control rats under experimental conditions.  On the 12th day of ischemic-reperfusion period in CA1 field all the indices of activity of Hif-1α transcriptional factor increase exceeding corresponding indices by absolute values in animals of the control group under the same experimental conditions, in СА2 and СА3 fields changes of the examined parameters are limited as compared to the same ones in animals from the control group, in CA4 field values that were increased in the control group decrease. Conclusions. Diabetes mellitus restricts reaction of Hif-1α protein on ischemia-reperfusion inn the neurons of СА1-СА3 fields in

  16. Attenuation of ischemia/reperfusion-induced inhibition of the rapid component of delayed rectifier potassium current by Isosteviol through scavenging reactive oxygen species.

    Yin, Chunxia; Chen, Yaoxu; Wu, Huanlin; Xu, Danping; Tan, Wen

    2017-12-01

    Isosteviol has been demonstrated to play a protective role during ischemia reperfusion (I/R) myocardial infarction. However, the underlying electrophysiological mechanisms of isosteviol are still unknown. Our previous study showed that the rapid component of the delayed rectifier potassium channel (I Kr ) plays an important role in the prolongation of I/R-induced QT interval-related arrhythmia. This study aimed to investigate whether isosteviol could attenuate I/R-induced prolongation of the action potential duration (APD) along with inhibition of I Kr , and we aimed to clarify the electrophysiological mechanism of isosteviol to determine its cardioprotective effects in guinea pigs. We observed that the APD 90 were 298.5±41.6ms in control, 528.6±56.7ms during I/R, and reduced to 327.8±40.5ms after 10μmol/L of isosteviol treatment. The I Kr currents were 1.44±0.06 pA·pF -1 in the control group, 0.50±0.07pA·pF -1 during I/R, and recovered to 1.20±0.12pA·pF -1 after 10μmol/L of isoteviol treatment. Moreover, isosteviol reduced the over-production of reactive oxygen species (ROS) during I/R. Importantly, isosteviol does not affect the I Kr and human ether-a-go-go-related gene currents of normal cardiomyocytes. It attenuated the I/R-induced inhibition of I Kr due to reduced over-production of ROS. Furthermore, isosteviol is safe and has no cardiotoxicity, and it might be beneficial for coronary reperfusion therapy. Copyright © 2017. Published by Elsevier B.V.

  17. Early intervention with human albumin to reduce the tissue plasminogen activator-mediated blood-brain barrier permeability damaged by delayed reperfusion: an experimental study in rats

    Lu Haitao; Zhao Jungong; Li Minghua; Li Yongdong; Zhang Peilei

    2011-01-01

    Objective: To clarify whether early use of high-dose human albumin can reduce the permeability of blood-brain barrier (BBB) damaged by delayed thrombolysis or not, and, in tun, reduce the vasogenic brain edema. Methods: A total of 138 male SD rats weighing 320-380 grams were randomly divided into 4 groups: sham operation group (n=3), control group (n=45), albumin group (n=45) and albumin+rt-PA group (n=45). According to the reperfusion time after the onset of middle cerebral artery occlusion (MCAO), each group, except sham operation group, was divided into three subgroups of 2 h, 3 h and 4 h with 15 rats in each subgroup. Rats in albumin group and albumin+rt-PA group received an intravenous infusion of 20% human albumin (2.5 g/kg) 2 hours after the onset of MCAO, and rats in albumin+rt-PA group received an intravenous infusion of rt-PA (10 mg/kg) at all points of reperfusion time via the rat's femoral vein immediately after the reperfusion. All rats were sacrificed 24 hours after MCAO, the infarct volume of the brain was determined with TTC dye method, the leakage extent of BBB was quantitatively estimated by using Evans blue method, and the matrix metalloproteinase-9 (MMP-9) expression was assessed with immunohistochemistry technique. Results: Early intervention with the use of high-dose human albumin could significantly improve the neurological score at 24 h. In MCAO 3 h albumin group, MCAO 4 h albumin group and MCAO 3 h albumin+rt-PA group, neurological score was significantly better than that in the control group (P 0.05). The volume of the infarct tissue was also significantly smaller in all the treated groups with high-dose human albumin groups (P<0.05) when compared with the control group. The infarct volume of the MCAO 4 h in albumin group and albumin+rt-PA group was reduced by 23% and by 17.3%, respectively. Cerebral hemorrhage transformation occurred in two rats of MCAO 4 h control group, in one rat of MCAO 4 h albumin group and in one rat of MCAO 4 h

  18. [Study on three kinds of gasoline oxygenates-induced DNA damage in mice fibroblasts].

    Song, Chonglin; Zhang, Zhifu; Chen, Xue; Zhang, Yanfeng; Wang, Chunhua; Liu, Keming

    2002-10-01

    To study DNA damage of three kinds of gasoline oxygenates. Single cell gel electrophoresis assay(Comet assay) was used to detect the damage effects of three gasoline oxygenates[methyl tertiary butyl ether(MTBE), ethanol anhydrous(EA) and dimethyl carbonate(DMC)] on DNA in L-929 mice fibroblasts. In certain concentation(37.500-150.000 mg/ml), MTBE could directly cause DNA damage of L-929 mice fibroblasts. There was obvious dose-effect relationship, i.e. when the concentration of MTBE was increased from 9.375 to 150.000 mg/ml, the comet rate also increased from 4% to 85%, and the length of comet tail changed correspondingly. The results of EA and DMC were negative. Under the condition of this experiment(150.000 mg/ml), MTBE could directly cause DNA damage while the effect of EA and DMC on DNA damage was not found.

  19. Neuroprotective effects of orientin on oxygen-glucose deprivation/reperfusion-induced cell injury in primary culture of rat cortical neurons.

    Tian, Tian; Zeng, Junan; Zhao, Guangyu; Zhao, Wenjing; Gao, Songyi; Liu, Li

    2018-01-01

    Orientin (luteolin-8-C-glucoside) is a phenolic compound found abundantly in millet, juice, and peel of passion fruit and has been shown to have antioxidant properties. In the present study, we explored the effects of orientin on oxygen-glucose deprivation/reperfusion (OGD/RP)-induced cell injury in primary culture of rat cortical neurons using an in vitro model of neonatal ischemic brain injury. The reduced cell viability and elevated lactate dehydrogenase leakage were observed after OGD/RP exposure, which were then reversed by orientin (10, 20, and 30 µM) pretreatment in a dose-dependent manner. Additionally, OGD/RP treatment resulted in significant oxidative stress, accompanied by enhanced intracellular reactive oxygen species (ROS) generation, and obvious depletion in the activities of intracellular Mn-superoxide dismutase, catalase, and glutathione peroxidase antioxidases. However, these effects were dose dependently restored by orientin pretreatment. We also found that orientin pretreatment dose dependently suppressed [Ca 2+ ] i increase and mitochondrial membrane potential dissipation caused by OGD/RP in primary culture of rat cortical neurons. Western blot analysis showed that OGD/RP exposure induced a distinct decrease of Bcl-2 protein and a marked elevation of Bax, caspase-3, and cleaved caspase-3 proteins; whereas these effects were dose dependently reversed by orientin incubation. Both the caspase-3 activity and the apoptosis rate were increased under OGD/RP treatment, but was then dose dependently down-regulated by orientin (10, 20, and 30 µM) incubation. Moreover, orientin pretreatment dose dependently inhibited OGD/RP-induced phosphorylation of JNK and ERK1/2. Notably, JNK inhibitor SP600125 and ERK1/2 inhibitor PD98059 also dramatically attenuated OGD/RP-induced cell viability loss and ROS generation, and further, orientin failed to protect cortical neurons with the interference of JNK activator anisomycin or ERK1/2 activator FGF-2. Taken

  20. A novel vitamin E derivative (TMG) protects against gastric mucosal damage induced by ischemia and reperfusion in rats.

    Ichikawa, Hiroshi; Yoshida, Norimasa; Takano, Hiroshisa; Ishikawa, Takeshi; Handa, Osamu; Takagi, Tomohisa; Naito, Yuji; Murase, Hironobu; Yoshikawa, Toshikazu

    2003-01-01

    The aim of the present study was to investigate the antioxidative effects of water-soluble vitamin E derivative, 2-(alpha-D-glucopyranosyl)methyl-2,5,7,8-tetramethylchroman-6-ol (TMG), on ischemia-reperfusion (I/R) -induced gastric mucosal injury in rats. Gastric ischemia was induced by applying a small clamp to the celiac artery and reoxygenation was produced by removal of the clamp. The area of gastric mucosal erosion, the concentration of thiobarbituric acid-reactive substances, and the myeloperoxidase activity in gastric mucosa significantly increased in I/R groups compared with those of sham-operated groups. These increases were significantly inhibited by pretreatment with TMG. The contents of both mucosal TNF-alpha and CINC-2beta in I/R groups were also increased compared with the levels of those in sham-operated groups. These increases of the inflammatory cytokines were significantly inhibited by the treatment with TMG. It is concluded that TMG inhibited lipid peroxidation and reduced development of the gastric mucosal inflammation induced by I/R in rats.

  1. Post-irradiation modification of oxygen-dependent and independent damage by catalase in barley seeds

    Sah, N.K.; Kesavan, P.C.

    1987-01-01

    If H 2 O 2 is one of the major mediators of the 'oxygen effect' in biological systems then catalase, which enzymically decomposes H 2 O 2 should have a significant influence on radiation damage, particularly under oxygenated conditions. The post-irradiation (300 Gy gamma rays) effect of catalase was, therefore, assessed on barley seeds of about 4% moisture content under oxygenated and oxygen-free conditions at varying temperatures. Catalase affords concentration-dependent radioprotection under oxygenated condition at both 25 0 C and 4 0 C. The level of protection at 4 0 C is less than at 25 0 C. This is obviously due to a decrease in catalase activity at low temperature. Under oxygen-free conditions, catalase enhances radiation damage at 4 0 C while at 25 0 C it it has no effect. This has been substantiated by data on the frequency of chromosomal aberrations and on peroxidase activity. Sodium azide, a catalase inhibitor, was found to eliminate the radioprotective action of catalase. The study supports the view that the 'oxygen effect' is mediated largely through peroxides in irradiated biological systems. However, the observations made particularly at 4 0 C under oxygen-free condition seem to involve physicochemical reactions. (author)

  2. The neuroprotective effect of hyperbaric oxygen treatment on laser-induced retinal damage in rats

    Vishnevskia-Dai, Victoria; Belokopytov, Mark; Dubinsky, Galina; Nachum, Gal; Avni, Isaac; Belkin, Michael; Rosner, Mordechai

    2005-04-01

    Retinal damage induced by mechanical trauma, ischemia or laser photocoagulation increases considerably by secondary degeneration processes. The spread of damage may be ameliorated by neuroprotection that is aimed at reducing the extent of the secondary degeneration and promote healing processes. Hyperbaric oxygen (HBO) treatment consists of inspiration of oxygen at higher than one absolute atmospheric pressure. Improved neural function was observed in patients with acute brain trauma or ischemia treated with HBO. This study was designed to evaluate the neuroprotective effect of hyperbaric oxygen (HBO) on laser induced retinal damage in a rat model. Standard argon laser lesions were created in 25 pigmented rats divided into three groups: Ten rats were treated immediately after the irradiation with HBO three times during the first 24 hr followed by 12 consecutive daily treatments. Five rats received a shorter treatment regimen of 10 consecutive HBO treatments. The control group (10 rats) underwent the laser damage with no additional treatment. The retinal lesions were evaluated 20 days after the injury. All outcome measures were improved by the longer HBO treatment (Ptreatment was less effective, showing an increase only in nuclei density at the central area of lesion (Pretinal damage in a rat model. In the range of HBO exposures studied, longer exposure provides more neuroprotection. These results encourage further evaluation of the potential therapeutic use of hyperbaric oxygen in diseases and injuries of the retina.

  3. Lycium barbarum polysaccharides reduce neuronal damage, blood-retinal barrier disruption and oxidative stress in retinal ischemia/reperfusion injury.

    Suk-Yee Li

    Full Text Available Neuronal cell death, glial cell activation, retinal swelling and oxidative injury are complications in retinal ischemia/reperfusion (I/R injuries. Lycium barbarum polysaccharides (LBP, extracts from the wolfberries, are good for "eye health" according to Chinese medicine. The aim of our present study is to explore the use of LBP in retinal I/R injury. Retinal I/R injury was induced by surgical occlusion of the internal carotid artery. Prior to induction of ischemia, mice were treated orally with either vehicle (PBS or LBP (1 mg/kg once a day for 1 week. Paraffin-embedded retinal sections were prepared. Viable cells were counted; apoptosis was assessed using TUNEL assay. Expression levels of glial fibrillary acidic protein (GFAP, aquaporin-4 (AQP4, poly(ADP-ribose (PAR and nitrotyrosine (NT were investigated by immunohistochemistry. The integrity of blood-retinal barrier (BRB was examined by IgG extravasations. Apoptosis and decreased viable cell count were found in the ganglion cell layer (GCL and the inner nuclear layer (INL of the vehicle-treated I/R retina. Additionally, increased retinal thickness, GFAP activation, AQP4 up-regulation, IgG extravasations and PAR expression levels were observed in the vehicle-treated I/R retina. Many of these changes were diminished or abolished in the LBP-treated I/R retina. Pre-treatment with LBP for 1 week effectively protected the retina from neuronal death, apoptosis, glial cell activation, aquaporin water channel up-regulation, disruption of BRB and oxidative stress. The present study suggests that LBP may have a neuroprotective role to play in ocular diseases for which I/R is a feature.

  4. Impact of oxygen concentration on yields of DNA damages caused by ionizing radiation

    Štěpán, Václav; Davídková, Marie

    2008-01-01

    Roč. 101, 012015 (2008), s. 1-4 ISSN 1742-6588. [Radiation Damage in Biomolecular Systems, RADAM'07. Dublin, 19.06.2007-22.06.2007] R&D Projects: GA ČR(CZ) GD202/05/H031; GA ČR GA202/05/2728 Institutional research plan: CEZ:AV0Z10480505 Keywords : radiation damage to DNA * oxygen concentration * theoretical modeling Subject RIV: BO - Biophysics

  5. Evaluation of Connexin 43 Redistribution and Endocytosis in Astrocytes Subjected to Ischemia/Reperfusion or Oxygen-Glucose Deprivation and Reoxygenation

    Hongyan Xie

    2017-01-01

    Full Text Available Connexin 43 (Cx43 is the major component protein in astrocytic gap junction communication. Recent studies have shown the cellular processes of gap junction internalization and degradation, but many details remain unknown. This study investigated the distribution of Cx43 and its mechanism after ischemic insult. Astrocyte culture system and a model of ischemia/reperfusion (IR or oxygen-glucose deprivation and reoxygenation (OGDR were established. Cx43 distribution was observed by laser scanning confocal microscopy under different cultivation conditions. Western blot and RT-PCR assays were applied to quantify Cx43 and MAPRE1 (microtubule-associated protein RP/EB family member 1 expression at different time points. The total number of Cx43 was unchanged in the normal and IR/OGDR groups, but Cx43 particles in the cytoplasm of the IR/OGDR group were significantly greater than that of the normal group. Particles in the cytoplasm were significantly fewer after endocytosis was blocked by dynasore. There was no difference among the groups at each time point regarding protein or gene expression of MAPRE1. We concluded that internalization of Cx43 into the cytoplasm occurred during ischemia, which was partially mediated through endocytosis, not by the change of Cx43 quantity. Moreover, internalization was not related to microtubule transport.

  6. Influence of oxygen at high pressure on the induction of damage in barley seeds by gamma radiation

    Donaldson, E.; Nilan, R.A.; Konzak, C.F.

    1978-01-01

    The influence of oxygen pressure prior to, during, and after irradiation on the induction of radiation damage was investigated using Himalaya (C.I. 620) barley seeds. Seeds were adjusted to water contents of 2 to 14% and then irradiated with 60 Co gamma rays in vacuo or under various oxygen tensions. After irradiation, the seeds were rehydrated at approximately 0 0 C in water continuously bubbled with oxygen or nitrogen. Biological effects of the treatments were recorded as M 1 seedling injury. Seeds irradiated in oxygen pressure sustained two or three times more damage than those irradiated in vacuo followed by rehydrating in oxygenated water. Greater damage occurred when seeds were (a) exposed to oxygen pressure and the pressure released before irradiation, (b) irradiated under oxygen pressure, or (c) irradiated in vacuo and then exposed to oxygen pressure than when irradiated in vacuo and rehydrated in oxygenated water. These results suggest that seeds can be saturated with oxygen before irradiation and also that the radiation-induced sites (presumably free radicals) which react with the oxygen are somewhat stable in very dry seeds. That the reaction probably occurs before the seeds are rehydrated was demonstrated by the failure to remove the effect of oxygen pressure between high oxygen pressure treatment and irradiation. The results indicate that placing the seeds under oxygen pressure may increase the rate and extent of the reactions occurring during post-radiation storage of seeds in the presence of oxygen. The increase in damage associated with aerobic rehydration is partially lost during aerobic storage and is largely pre-empted when seeds are placed under oxygen pressure. The decrease in damage associated with aerobic rehydration is accompanied by an increase in damage occurring with anaerobic rehydration, suggesting that the reaction which leads to damage was initiated before rehydration and to the same oxygen sensitive sites

  7. KLF5 overexpression attenuates cardiomyocyte inflammation induced by oxygen-glucose deprivation/reperfusion through the PPARγ/PGC-1α/TNF-α signaling pathway.

    Li, Yang; Li, Jian; Hou, Zhiwen; Yu, Yang; Yu, Bo

    2016-12-01

    The primary physiological function of Krüppel-like zinc-finger transcription factor (KLF5) is the regulation of cardiovascular remodeling. Vascular remodeling is closely related to the amelioration of various ischemic diseases. However, the underlying correlation of KLF5 and ischemia is not clear. In this study, we aim to investigate the role of KLF5 in myocardial ischemia reperfusion (IR) injury and the potential mechanisms involved. Cultured H9C2 cells were subjected to oxygen-glucose deprivation/reperfusion (OGD/Rep) to mimic myocardial IR injury in vivo. Expressions of KLF5 and PPARγ were distinctly inhibited, and PGC-1α expression was activated at 24h after myocardial OGD/Rep injury. After myocardial OGD/Rep injury, we found that KLF5 overexpression down-regulated levels of TNF-α, IL-1β, IL-6 and IL-8. Through the analysis of lactate dehydrogenase (LDH) release, we demonstrate that KLF5 overexpression reduced the release of OGD/Rep-induced LDH. KLF5 overexpression significantly enhanced cell activity and decreased cell apoptosis during OGD/Rep injury. Compared with the OGD/Rep group, cells overexpressing KLF5 showed anti-apoptotic effects, such as decreased expression of Bax and cleaved caspase-3 as well as increased Bcl-2 expression. KLF5 overexpression activated PPARγ, a protein involved in OGD/Rep injury, and increased levels of PGC-1α, while TNF-α expression was remarkably inhibited. In addition, GW9662, a PPARγ receptor antagonist, reversed the expression of PPARγ/PGC-1α/TNF-α and cell activity induced by KLF5 overexpression. The effects of KLF5 overexpression on PPARγ/PGC-1α/TNF-α and cell activity were abolished by co-treatment with GW9662. Taken together, these results suggest that KLF5 can efficiently alleviate OGD/Rep-induced myocardial injury, perhaps through regulation of the PPARγ/PGC-1α/TNF-α pathway. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  8. Oxygen effect on mutagenic ionizing radiation damage in Bacillus subtilis spores of DNA polymerase I-proficient and -deficient strains

    Tanooka, H.

    1980-01-01

    The nature of mutagenic ionizing radiation damage modified by the presence of oxygen or water was examined by comparing mutagenic with lethal expression of the damage in Bacillus subtilis spores irradiated with 6-MeV electrons. No specific difference was recognized between oxygen-dependent and -independent damages or between polA + -dependent and -independent damages with this system. The induced mutation frequency for His + mutation per lethal hit was 4.7 x 10 -5 for all tested cases

  9. Partridgeberry polyphenols protect rat primary cortical neurons from oxygen-glucose deprivation-reperfusion-induced injury via suppression of inflammatory adipokines and regulation of HIF-1α and PPARγ.

    Bhullar, Khushwant S; Rupasinghe, H P Vasantha

    2016-07-01

    The aim of this study was to investigate the neuroprotective ability of partridgeberry polyphenols in rat primary cortical neurons against oxygen-glucose deprivation/reperfusion (OGD/R) injury in vitro and explore the underlying therapeutic mechanism(s). The OGD/R injury was induced in rat primary cortical neurons by incubation with deoxygenated glucose-free medium in a hypoxia chamber. The strongest activity in this regard was exhibited by partridgeberry-derived PPF2 and PPF3, i.e. the flavan-3-ol- and flavonol-rich polyphenol fractions of partridgeberry (P ≤ 0.05). Moreover, partridgeberry polyphenol pre-treatment reduced the membrane damage in primary neurons, as measured by the lactose dehydrogenase (LDH) release assay (P ≤ 0.05). Furthermore, PPF2 and PPF3 pre-treatment (100 µg ml(-1)) for 24 hours, before OGD/R, resulted in the strongest suppression of interleukin (IL)-6 and tumor necrosis factor-α induction by OGD/R injury, compared with the control group (P ≤ 0.05). Additionally, the protein levels of hypoxia-inducible factor (HIF-1α) and PPARγ, quantified by ELISA presented a significant modulation following PPFs treatment (100 µg ml(-1)), favorably toward neuroprotection, compared with the respective controls after OGD/R injury in vitro (P ≤ 0.05). In summary, partridgeberry polyphenols at concentrations of 1-100 µg ml(-1), significantly induced a decline in OGD/R injury-triggered apoptosis in vitro, suppressed the inflammatory biomarkers in primary neurons, and modulated the activity of HIF-1α and proliferator-activated receptor gamma (PPARγ) following hypoxic injury.

  10. Activation of the Nrf2/HO-1 Antioxidant Pathway Contributes to the Protective Effects of Lycium Barbarum Polysaccharides in the Rodent Retina after Ischemia-Reperfusion-Induced Damage

    Chang, Raymond Chuen-Chung; So, Kwok-Fai; Brecha, Nicholas C.; Pu, Mingliang

    2014-01-01

    Lycium barbarum polysaccharides (LBP), extracts from the wolfberries, are protective to retina after ischemia-reperfusion (I/R). The antioxidant response element (ARE)–mediated antioxidant pathway plays an important role in maintaining the redox status of the retina. Heme oxygenase-1 (HO-1), combined with potent AREs in its promoter, is a highly effective therapeutic target for the protection against neurodegenerative diseases, including I/R-induced retinal damage. The aim of our present study was to investigate whether the protective effect of LBP after I/R damage was mediated via activation of the Nrf2/HO-1-antioxidant pathway in the retina. Retinal I/R was induced by an increase in intraocular pressure to 130 mm Hg for 60 minutes. Prior to the induction of ischemia, rats were orally treated with either vehicle (PBS) or LBP (1 mg/kg) once a day for 1 week. For specific experiments, zinc protoporphyrin (ZnPP, 20 mg/kg), an HO-1 inhibitor, was intraperitoneally administered at 24 h prior to ischemia. The protective effects of LBP were evaluated by quantifying ganglion cell and amacrine cell survival, and by measuring cell apoptosis in the retinal layers. In addition, HO-1 expression was examined using Western blotting and immunofluorescence analyses. Cytosolic and nuclear Nrf2 was measured using immunofluorescent staining. LBP treatment significantly increased Nrf2 nuclear accumulation and HO-1 expression in the retina after I/R injury. Increased apoptosis and a decrease in the number of viable cells were observed in the ganglion cell layer (GCL) and inner nuclear layer (INL) in the I/R retina, which were reversed by LBP treatment. The HO-1 inhibitor, ZnPP, diminished the LBP treatment-induced protective effects in the retina after I/R. Taken together, these results suggested that LBP partially exerted its beneficial neuroprotective effects via the activation of Nrf2 and an increase in HO-1 protein expression. PMID:24400114

  11. Reduction of skin damage from transcutaneous oxygen electrodes using a spray on dressing.

    Evans, N J; Rutter, N

    1986-09-01

    A spray on, copolymer acrylic dressing (Op-Site) was used to limit the skin damage caused by a transcutaneous oxygen electrode and its adhesive ring. Two identical electrodes were applied to the abdominal skin of 10 preterm infants, one on untreated skin, the other after application of Op-Site. It was found that Op-Site prevented the epidermal damage (as measured by transepidermal water loss) that occurs when the adhesive ring is removed from untreated skin. It did not interfere with transcutaneous oxygen measurements; absolute values and response times were unchanged. Op-Site is therefore useful in preventing the skin trauma that occurs when transcutaneous oxygen monitoring is being performed in preterm infants below 30 weeks' gestation in the first week of life. Care must be taken, however, to prevent a build up of Op-Site--it should be applied as a single layer, allowed to dry, and removed after use.

  12. Protective effect of Kombucha tea on brain damage induced by transient cerebral ischemia and reperfusion in rat

    Najmeh Kabiri

    2016-09-01

    Full Text Available The aim of study was to investigate the potential neuroprotective effects of Kombucha on cerebral damage induced by ischemia in rats (n=99. Cerebral infarct volume in the ischemic rats received Kombucha solution showed no significance alteration. However, the permeability of blood-brain barrier significantly decreased in both ischemic rats received 15 mg/kg Kombucha tea and Sham group. In addition, brain water content in the ischemic groups treated with Kombucha solution was significantly higher than the Sham group, although right hemispheres in all of the treated groups illustrated higher brain water content than the left ones. Brain anti-oxidant capacity elevated in the ischemic rats treated with Kombucha and in the Sham group. Brain and plasma malondialdehyde concentrations significantly decreased in both of the ischemic groups injected with Kombucha. The findings suggest that Kombucha tea could be useful for the prevention of cerebral damage.

  13. Cellular defense against singlet oxygen-induced oxidative damage by cytosolic NADP+-dependent isocitrate dehydrogenase.

    Kim, Sun Yee; Park, Jeen-Woo

    2003-03-01

    Singlet oxygen (1O2) is a highly reactive form of molecular oxygen that may harm living systems by oxidizing critical cellular macromolecules. Recently, we have shown that NADP+-dependent isocitrate dehydrogenase is involved in the supply of NADPH needed for GSH production against cellular oxidative damage. In this study, we investigated the role of cytosolic form of NADP+-dependent isocitrate dehydrogenase (IDPc) against singlet oxygen-induced cytotoxicity by comparing the relative degree of cellular responses in three different NIH3T3 cells with stable transfection with the cDNA for mouse IDPc in sense and antisense orientations, where IDPc activities were 2.3-fold higher and 39% lower, respectively, than that in the parental cells carrying the vector alone. Upon exposure to singlet oxygen generated from photoactivated dye, the cells with low levels of IDPc became more sensitive to cell killing. Lipid peroxidation, protein oxidation, oxidative DNA damage and intracellular peroxide generation were higher in the cell-line expressing the lower level of IDPc. However, the cells with the highly over-expressed IDPc exhibited enhanced resistance against singlet oxygen, compared to the control cells. The data indicate that IDPc plays an important role in cellular defense against singlet oxygen-induced oxidative injury.

  14. Protective effect of Kombucha tea on brain damage induced by transient cerebral ischemia and reperfusion in rat

    Najmeh Kabiri; Mahbubeh Setorki

    2016-01-01

    The aim of study was to investigate the potential neuroprotective effects of Kombucha on cerebral damage induced by ischemia in rats (n=99). Cerebral infarct volume in the ischemic rats received Kombucha solution showed no significance alteration. However, the permeability of blood-brain barrier significantly decreased in both ischemic rats received 15 mg/kg Kombucha tea and Sham group. In addition, brain water content in the ischemic groups treated with Kombucha solution was significantly hi...

  15. Global brain ischemia and reperfusion.

    White, B C; Grossman, L I; O'Neil, B J; DeGracia, D J; Neumar, R W; Rafols, J A; Krause, G S

    1996-05-01

    Brain damage accompanying cardiac arrest and resuscitation is frequent and devastating. Neurons in the hippocampus CA1 and CA4 zones and cortical layers III and V are selectively vulnerable to death after injury by ischemia and reperfusion. Ultrastructural evidence indicates that most of the structural damage is associated with reperfusion, during which the vulnerable neurons develop disaggregation of polyribosomes, peroxidative damage to unsaturated fatty acids in the plasma membrane, and prominent alterations in the structure of the Golgi apparatus that is responsible for membrane assembly. Reperfusion is also associated with vulnerable neurons with prominent production of messenger RNAs for stress proteins and for the proteins of the activator protein-1 complex, but these vulnerable neurons fail to efficiently translate these messages into the proteins. The inhibition of protein synthesis during reperfusion involves alteration of translation initiation factors, specifically serine phosphorylation of the alpha-subunit of eukaryotic initiation factor-2 (elF-2 alpha). Growth factors--in particular, insulin--have the potential to reverse phosphorylation of elF-2 alpha, promote effective translation of the mRNA transcripts generated in response to ischemia and reperfusion, enhance neuronal defenses against radicals, and stimulate lipid synthesis and membrane repair. There is now substantial evidence that the insulin-class growth factors have neuron-sparing effects against damage by radicals and ischemia and reperfusion. This new knowledge may provide a fundamental basis for a rational approach to "cerebral resuscitation" that will allow substantial amelioration of the often dismal neurologic outcome now associated with resuscitation from cardiac arrest.

  16. Two-photon imaging during prolonged middle cerebral artery occlusion in mice reveals recovery of dendritic structure after reperfusion.

    Li, Ping; Murphy, Timothy H

    2008-11-12

    Filament occlusion of the middle cerebral artery (MCA) is a well accepted animal model of focal ischemia. Advantages of the model are relatively long occlusion times and a large penumbra region that simulates aspects of human stroke. Here, we use two-photon and confocal microscopy in combination with regional measurement of blood flow using laser speckle to assess the spatial relationship between the borders of the MCA ischemic territory and loss of dendrite structure, as well as the effect of reperfusion on dendritic damage in adult YFP (yellow fluorescent protein) and GFP (green fluorescent protein) C57BL/6 transgenic mice with fluorescent (predominantly layer 5) neurons. By examining the spatial extent of dendritic damage, we determined that 60 min of MCA occlusion produced a core with severe structural damage that did not recover after reperfusion (begins approximately 3.8 mm lateral to midline), a reversibly damaged area up to 0.6 mm medial to the core that recovered after reperfusion (penumbra), and a relatively structurally intact area ( approximately 1 mm wide; medial penumbra) with hypoperfusion. Loss of structure was preceded by a single ischemic depolarization 122.1 +/- 10.2 s after occlusion onset. Reperfusion of animals after 60 min of ischemia was not associated with exacerbation of damage (reperfusion injury) and resulted in a significant restoration of blebbed dendritic structure, but only within approximately 0.6 mm lateral of the dendritic damage structural border. In summary, we find that recovery of dendritic structure can occur after reperfusion after even 60 min of ischemia, but is likely restricted to a relatively small penumbra region with partial blood flow or oxygenation.

  17. Protection against Oxygen-Glucose Deprivation/Reperfusion Injury in Cortical Neurons by Combining Omega-3 Polyunsaturated Acid with Lyciumbarbarum Polysaccharide.

    Shi, Zhe; Wu, Di; Yao, Jian-Ping; Yao, Xiaoli; Huang, Zhijian; Li, Peng; Wan, Jian-Bo; He, Chengwei; Su, Huanxing

    2016-01-13

    Ischemic stroke, characterized by the disturbance of the blood supply to the brain, is a severe worldwide health threat with high mortality and morbidity. However, there is no effective pharmacotherapy for ischemic injury. Currently, combined treatment is highly recommended for this devastating injury. In the present study, we investigated neuroprotective effects of the combination of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) and Lyciumbarbarum polysaccharide (LBP) on cortical neurons using an in vitro ischemic model. Our study demonstrated that treatment with docosahexaenoic acid (DHA), a major component of the ω-3 PUFAs family, significantly inhibited the increase of intracellular Ca(2+) in cultured wild type (WT) cortical neurons subjected to oxygen-glucose deprivation/reperfusion (OGD/R) injury and promoted their survival compared with the vehicle-treated control. The protective effects were further confirmed in cultured neurons with high endogenous ω-3 PUFAs that were isolated from fat-1 mice, in that a higher survival rate was found in fat-1 neurons compared with wild-type neurons after OGD/R injury. Our study also found that treatment with LBP (50 mg/L) activated Trk-B signaling in cortical neurons and significantly attenuated OGD/R-induced cell apoptosis compared with the control. Notably, both combining LBP treatment with ω-3 PUFAs administration to WT neurons and adding LBP to fat-1 neurons showed enhanced effects on protecting cortical neurons against OGD/R injury via concurrently regulating the intracellular calcium overload and neurotrophic pathway. The results of the study suggest that ω-3 PUFAs and LBP are promising candidates for combined pharmacotherapy for ischemic stroke.

  18. Protective effect of Mangifera indica L. extract (Vimang) on the injury associated with hepatic ischaemia reperfusion.

    Sánchez, Gregorio Martínez; Rodríguez H, María A; Giuliani, Attilia; Núñez Sellés, Alberto J; Rodríguez, Niurka Pons; León Fernández, Olga Sonia; Re, L

    2003-03-01

    The effect of Mangifera indica L. extract (Vimang) on treatment of injury associated with hepatic ischaemia/reperfusion was tested. Vimang protects from the oxidative damage induced by oxygen-based free radicals as shown in several in vitro test systems conducted. The ability of Vimang to reduce liver damage was investigated in rats undergoing right-lobe blood fl ow occlusion for 45 min followed by 45 min of reperfusion. The ischaemia/reperfusion model leads to an increase of transaminase (ALT and AST), membrane lipid peroxidation, tissue neutrophil in filtration, DNA fragmentation, loss of protein -SH groups, cytosolic Ca2+ overload and a decrease of catalase activity. Oral administration of Vimang (50, 110 and 250 mg/kg, b.w.) 7 days before reperfusion, reduced transaminase levels and DNA fragmentation in a dose dependent manner (p Vimang also restored the cytosolic Ca2+ levels and inhibited polymorphonuclear migration at a dose of 250 mg/kg b.w., improved the oxidation of total and non protein sulfhydryl groups and prevented modification in catalase activity, uric acid and lipid peroxidation markers (p Vimang could be a useful new natural drug for preventing oxidative damage during hepatic injury associated with free radical generation. Copyright 2003 John Wiley & Sons, Ltd.

  19. Reduction of skin damage from transcutaneous oxygen electrodes using a spray on dressing.

    Evans, N J; Rutter, N

    1986-01-01

    A spray on, copolymer acrylic dressing (Op-Site) was used to limit the skin damage caused by a transcutaneous oxygen electrode and its adhesive ring. Two identical electrodes were applied to the abdominal skin of 10 preterm infants, one on untreated skin, the other after application of Op-Site. It was found that Op-Site prevented the epidermal damage (as measured by transepidermal water loss) that occurs when the adhesive ring is removed from untreated skin. It did not interfere with transcut...

  20. Inhibition of microRNA-153 protects neurons against ischemia/reperfusion injury in an oxygen-glucose deprivation and reoxygenation cellular model by regulating Nrf2/HO-1 signaling.

    Ji, Qiong; Gao, Jianbo; Zheng, Yan; Liu, Xueli; Zhou, Qiangqiang; Shi, Canxia; Yao, Meng; Chen, Xia

    2017-07-01

    MicroRNAs are emerging as critical regulators in cerebral ischemia/reperfusion injury; however, their exact roles remain poorly understood. miR-153 is reported to be a neuron-related miRNA involved in neuroprotection. In this study, we aimed to investigate the precise role of miR-153 in regulating neuron survival during cerebral ischemia/reperfusion injury using an oxygen-glucose deprivation and reoxygenation (OGD/R) cellular model. We found that miR-153 was significantly upregulated in neurons subjected to OGD/R treatment. Inhibition of miR-153 significantly attenuated OGD/R-induced injury and oxidative stress in neurons. Nuclear factor erythroid 2-related factor 2 (Nrf2) was identified as a target gene of miR-153. Inhibition of miR-153 significantly promoted the expression of Nrf2 and heme oxygenase-1 (HO-1). However, silencing of Nrf2 significantly blocked the protective effects of miR-153 inhibition. Our study indicates that the inhibition of miR-153 protects neurons against OGD/R-induced injury by regulating Nrf2/HO-1 signaling and suggests a potential therapeutic target for cerebral ischemia/reperfusion injury. © 2017 Wiley Periodicals, Inc.

  1. Autophagy and Liver Ischemia-Reperfusion Injury

    Raffaele Cursio

    2015-01-01

    Full Text Available Liver ischemia-reperfusion (I-R injury occurs during liver resection, liver transplantation, and hemorrhagic shock. The main mode of liver cell death after warm and/or cold liver I-R is necrosis, but other modes of cell death, as apoptosis and autophagy, are also involved. Autophagy is an intracellular self-digesting pathway responsible for removal of long-lived proteins, damaged organelles, and malformed proteins during biosynthesis by lysosomes. Autophagy is found in normal and diseased liver. Although depending on the type of ischemia, warm and/or cold, the dynamic process of liver I-R results mainly in adenosine triphosphate depletion and in production of reactive oxygen species (ROS, leads to both, a local ischemic insult and an acute inflammatory-mediated reperfusion injury, and results finally in cell death. This process can induce liver dysfunction and can increase patient morbidity and mortality after liver surgery and hemorrhagic shock. Whether autophagy protects from or promotes liver injury following warm and/or cold I-R remains to be elucidated. The present review aims to summarize the current knowledge in liver I-R injury focusing on both the beneficial and the detrimental effects of liver autophagy following warm and/or cold liver I-R.

  2. Characterization of photoactivated singlet oxygen damage in single-molecule optical trap experiments.

    Landry, Markita P; McCall, Patrick M; Qi, Zhi; Chemla, Yann R

    2009-10-21

    Optical traps or "tweezers" use high-power, near-infrared laser beams to manipulate and apply forces to biological systems, ranging from individual molecules to cells. Although previous studies have established that optical tweezers induce photodamage in live cells, the effects of trap irradiation have yet to be examined in vitro, at the single-molecule level. In this study, we investigate trap-induced damage in a simple system consisting of DNA molecules tethered between optically trapped polystyrene microspheres. We show that exposure to the trapping light affects the lifetime of the tethers, the efficiency with which they can be formed, and their structure. Moreover, we establish that these irreversible effects are caused by oxidative damage from singlet oxygen. This reactive state of molecular oxygen is generated locally by the optical traps in the presence of a sensitizer, which we identify as the trapped polystyrene microspheres. Trap-induced oxidative damage can be reduced greatly by working under anaerobic conditions, using additives that quench singlet oxygen, or trapping microspheres lacking the sensitizers necessary for singlet state photoexcitation. Our findings are relevant to a broad range of trap-based single-molecule experiments-the most common biological application of optical tweezers-and may guide the development of more robust experimental protocols.

  3. Radiosensitization of mammalian cells by misonidazole and oxygen: DNA damage exposed by Micrococcus luteus enzymes

    Skov, K.A.; Palcic, B.; Skarsgard, L.D.

    1979-01-01

    When misonidazole is present during irradiation of hypoxic mammalian cells, an enhancement of single-strand breaks (SSB) in DNA is observed. Oxygen also enhances SSB, presumably in a manner similar to that of misonidazole. The dose-modifying factor (DMF) for 15 mM misonidazole was found to be 3.4, compared to an oxygen enhancement ratio (OER) of 3.5. Another class of DNA damage, namely, sites exposed by an extract of Micrococcus luteus, was examined. Radiation-induced M. luteus extract-sensitive sites (MLS) were also found to be enhanced by the presence of misonidazole or molecular oxygen. The DMF for this damage by 15 mM misonidazole was 1.6 while the OER was 2.5. The ratio of MLS to SSB is approximately 1.25 under hypoxia, 0.9 in the presence of oxygen, and 0.6 in the presence of 15 mM misonidazole under hypoxic conditions. Incubation with misonidazole under conditions which are toxic to mammalian cells (37 0 C, hypoxia), and which result in many SSB, produces no detectable lesions sensitive to the M. luteus extract

  4. EGFR mediates astragaloside IV-induced Nrf2 activation to protect cortical neurons against in vitro ischemia/reperfusion damages

    Gu, Da-min; Lu, Pei-Hua; Zhang, Ke; Wang, Xiang; Sun, Min; Chen, Guo-Qian; Wang, Qiong

    2015-01-01

    In this study, we tested the potential role of astragaloside IV (AS-IV) against oxygen and glucose deprivation/re-oxygenation (OGD/R)-induced damages in murine cortical neurons, and studied the associated signaling mechanisms. AS-IV exerted significant neuroprotective effects against OGD/R by reducing reactive oxygen species (ROS) accumulation, thereby attenuating oxidative stress and neuronal cell death. We found that AS-IV treatment in cortical neurons resulted in NF-E2-related factor 2 (Nrf2) signaling activation, evidenced by Nrf2 Ser-40 phosphorylation, and its nuclear localization, as well as transcription of antioxidant-responsive element (ARE)-regulated genes: heme oxygenase-1 (HO-1), NAD(P)H:quinone oxidoreductase 1 (NQO-1) and sulphiredoxin 1 (SRXN-1). Knockdown of Nrf2 through lentiviral shRNAs prevented AS-IV-induced ARE genes transcription, and abolished its anti-oxidant and neuroprotective activities. Further, we discovered that AS-IV stimulated heparin-binding-epidermal growth factor (HB-EGF) release to trans-activate epidermal growth factor receptor (EGFR) in cortical neurons. Blockage or silencing EGFR prevented Nrf2 activation by AS-IV, thus inhibiting AS-IV-mediated anti-oxidant and neuroprotective activities against OGD/R. In summary, AS-IV protects cortical neurons against OGD/R damages through activating of EGFR-Nrf2 signaling. - Highlights: • Pre-treatment of astragaloside IV (AS-IV) protects murine cortical neurons from OGD/R. • AS-IV activates Nrf2-ARE signaling in murine cortical neurons. • Nrf2 is required for AS-IV-mediated anti-oxidant and neuroprotective activities. • AS-IV stimulates HB-EGF release to trans-activate EGFR in murine cortical neurons. • EGFR mediates AS-IV-induced Nrf2 activation and neuroprotection against OGD/R

  5. EGFR mediates astragaloside IV-induced Nrf2 activation to protect cortical neurons against in vitro ischemia/reperfusion damages

    Gu, Da-min [Department of Anesthesiology, Affiliated Yixing People' s Hospital, Jiangsu University, Yixing (China); Lu, Pei-Hua, E-mail: lphty1_1@163.com [Department of Medical Oncology, Wuxi People' s Hospital Affiliated to Nanjing Medical University, Wuxi (China); Zhang, Ke; Wang, Xiang [Department of Anesthesiology, Affiliated Yixing People' s Hospital, Jiangsu University, Yixing (China); Sun, Min [Department of General Surgery, Affiliated Yixing People' s Hospital, Jiangsu University, Yixing (China); Chen, Guo-Qian [Department of Clinical Laboratory, Wuxi People' s Hospital Affiliated to Nanjing Medical University, Wuxi (China); Wang, Qiong, E-mail: WangQiongprof1@126.com [Department of Clinical Laboratory, Wuxi People' s Hospital Affiliated to Nanjing Medical University, Wuxi (China)

    2015-02-13

    In this study, we tested the potential role of astragaloside IV (AS-IV) against oxygen and glucose deprivation/re-oxygenation (OGD/R)-induced damages in murine cortical neurons, and studied the associated signaling mechanisms. AS-IV exerted significant neuroprotective effects against OGD/R by reducing reactive oxygen species (ROS) accumulation, thereby attenuating oxidative stress and neuronal cell death. We found that AS-IV treatment in cortical neurons resulted in NF-E2-related factor 2 (Nrf2) signaling activation, evidenced by Nrf2 Ser-40 phosphorylation, and its nuclear localization, as well as transcription of antioxidant-responsive element (ARE)-regulated genes: heme oxygenase-1 (HO-1), NAD(P)H:quinone oxidoreductase 1 (NQO-1) and sulphiredoxin 1 (SRXN-1). Knockdown of Nrf2 through lentiviral shRNAs prevented AS-IV-induced ARE genes transcription, and abolished its anti-oxidant and neuroprotective activities. Further, we discovered that AS-IV stimulated heparin-binding-epidermal growth factor (HB-EGF) release to trans-activate epidermal growth factor receptor (EGFR) in cortical neurons. Blockage or silencing EGFR prevented Nrf2 activation by AS-IV, thus inhibiting AS-IV-mediated anti-oxidant and neuroprotective activities against OGD/R. In summary, AS-IV protects cortical neurons against OGD/R damages through activating of EGFR-Nrf2 signaling. - Highlights: • Pre-treatment of astragaloside IV (AS-IV) protects murine cortical neurons from OGD/R. • AS-IV activates Nrf2-ARE signaling in murine cortical neurons. • Nrf2 is required for AS-IV-mediated anti-oxidant and neuroprotective activities. • AS-IV stimulates HB-EGF release to trans-activate EGFR in murine cortical neurons. • EGFR mediates AS-IV-induced Nrf2 activation and neuroprotection against OGD/R.

  6. The role of calcium in modulating the reactivity of the smooth muscle cells during ischemia/reperfusion. Part 2

    Katarzyna Szadujkis-Szadurska

    2010-04-01

    Full Text Available Background:Damage of transplanted organs during reperfusion is still a problem that prompts the search for new drugs able to diminish the risk of graft rejection. The aim of this study was to examine the influence of antioxidant system on the contraction of arteries induced by angiotensin II during ischemia/reperfusion and to determine the role of intracellular and extracellular calcium ions under these conditions.Material/Methods:The experiments were performed on male Wistar rats’ tail arteries. The effects of angiotensin II on vascular tone were examined after ischemia/reperfusion in the presence of catalase or aminotriazole. To determine the role of intracellular and extracellular Ca[sup]2 [/sup], the experiments were performed in Ca[sup]2 [/sup]-free PSS and PSS.Results:Angiotensin II increased perfusion pressure in both Ca[sup]2 [/sup]-free PSS and PSS. After ischemia, the reactions induced by angiotensin II were lower, while after reperfusion they were higher. In the presence of catalase the effects induced by angiotensin II were lower and in the presence of aminotriazole higher.Conclusions:Ischemia inhibits and reperfusion augments the perfusion pressure induced by angiotensin II. The results confirm the vasoprotective effect of catalase and the destructive influence of aminotriazole in modulating the reactions of vascular smooth muscle cells to ANG II after ischemia/reperfusion. These results suggest that the antioxidant system plays a role in modulating the reactions induced by angiotensin II after ischemia/reperfusion and that reperfusion disturbs the balance between antioxidants and the production of reactive oxygen species.

  7. Atomic Oxygen Treatment as a Method of Recovering Smoke Damaged Paintings

    Rutledge, Sharon K.; Banks, Bruce A.; Forkapa, Mark; Stueber, Thomas; Sechkar, Edward; Malinowski, Kevin

    1998-01-01

    Smoke damage, as a result of a fire, can be difficult to remove from some types of painting media without causing swelling, leaching or pigment movement or removal. A non-contact technique has been developed which can remove soot from the surface of a painting by use of a gently flowing gas containing atomic oxygen. The atomic oxygen chemically reacts with the soot on the surface creating gasses such as carbon monoxide and carbon dioxide which can be removed through the use of an exhaust system. The reaction is limited to the surface so that the process can be timed to stop when the paint layer is reached. Atomic oxygen is a primary component of the low Earth orbital environment, but can be generated on Earth through various methods. This paper will discuss the results of atomic oxygen treatment of soot exposed acrylic gesso, ink on paper, and a varnished oil painting. Reflectance measurements were used to characterize the surfaces before and after treatment.

  8. Damage induced by high energy multiply charged oxygen ions in oxide coated silicon

    Dhole, S.D. [Department of Physics, University of Pune, Pune 411 007 (India)]. E-mail: sanjay@physics.unipune.ernet.in; Dahiwale, S.S. [Department of Physics, University of Pune, Pune 411 007 (India); Kulkarni, V.R. [Department of Physics, University of Pune, Pune 411 007 (India); Bogle, K.A. [Department of Physics, University of Pune, Pune 411 007 (India); Shinde, N.S. [Ecotopia Science Institute, Division of Energy Science, Nagoya University, Nagoya (Japan); Bhoraskar, V.N. [Department of Physics, University of Pune, Pune 411 007 (India)

    2006-03-15

    P-type oxide coated silicon samples of resistivity 120 {omega} cm were irradiated with 60 MeV oxygen ions of fixed charge states 4{sup +}, 5{sup +}, 6{sup +} and 7{sup +} at an equal fluence of, {phi}, {approx}10{sup 13} ions/cm{sup 2}. The induced damage was estimated by Hall voltage, Hall coefficient, carrier concentration and lifetime of minority carriers. The results indicate that Hall voltage (V {sub H}) and Hall coefficient (R {sub H}) increases, while carrier concentration (n) decreases with the charge state of impinging oxygen ions. The V {sub H} increases from 22 mV to 76.5 mV at typical current of 0.5 mA, R {sub H} from 0.42 x 10{sup 5} cm{sup 3}/C to 2.16 x 10{sup 5} cm{sup 3}/C and n decreases from 9 x 10{sup 13} cm{sup -3} to 2.88 x 10{sup 13} cm{sup -3} for the different charge states. This fact is an evidence that the oxygen ions with an individual fixed charge state passing through very thin 40 A layer of silicon dioxide, induces significant damage at the SiO{sub 2}-Si interface through the mechanism of electronic stopping power. The lifetime of minority charge carriers, {tau} (bulk property), remains constant at around 6 {mu}s for all the charge states of the 60 MeV energy oxygen ion irradiated samples at a constant fluence of, {phi}, 10{sup 13} ions/cm{sup 2}.

  9. Atomic Oxygen Treatment as a Method of Recovering Smoke Damaged Paintings. Revised

    Rutledge, Sharon K.; Banks, Bruce A.; Forkapa, Mark; Stueber, Thomas; Sechkar, Edward; Malinowski, Kevin

    1999-01-01

    A noncontact technique is described that uses atomic oxygen, generated under low pressure in the presence of nitrogen, to remove soot and charred varnish from the surface of a painting. The process, which involves surface oxidation, permits control of the amount of surface material removed. The effectiveness of the process was evaluated by reflectance measurements from selected areas made during the removal of soot from acrylic gesso, ink on paper, and varnished oil paint substrates. For the latter substrate, treatment also involved the removal of damaged varnish and paint binder from the surface.

  10. Renal ischemia reperfusion causes brain hippocampus oxidative ...

    Background: The acute kidney injury (AKI) may do damage to remote organs. Objective of the study is to investigate effect of seaweed extract (SE) on brain oxidative damage in kidney ischemia/reperfusion rats. Material and Methods: Animals were randomly divided into five groups. SE pre-fed to rats. Results: Kidney I/R ...

  11. Melatonin Protective Effects against Liver Ischemia/Reperfusion Injury

    Abbas Khonakdar-Tarsi

    2016-02-01

    Full Text Available Hepatic ischemia-reperfusion (I/R is a common phenomenon during liver surgery, transplantation, infection and trauma which results in damage and necrosis of the hepatic tissue through different pathways. Mechanisms involved in I/R damage are very intricate and cover several aspects. Several factors are involved in I/R-induced damages; briefly, decrease in sinusoidal perfusion and ATP generation because of low or no O2 supply, increase in production of reactive oxygen species (ROS and inflammatory factors and destruction of parenchymal cells resulted by these molecules are of the main causes of liver tissue injury during reperfusion. Melatonin’s antioxidant effect, and regulatory roles in the expression of different genes in the I/R insulted liver have been investigated by several studies. Melatonin and its metabolites are of the powerful direct scavengers of free radicals and ROS, so it can directly protect liver cell impairment from oxidative stress following I/R. In addition, this bioactive molecule up-regulates anti-oxidant enzyme genes like superoxide dismutase (SOD, glutathione peroxidase (GSH-Px and catalase (CAT. Tumor necrosis factors (TNF-α and interleukin-1 (IL-1, as potent pro-inflammatory factors, are generated in huge amounts during reperfusion. Melatonin is able to alleviate TNF-α generation and has hepatoprotective effect during I/R. It reduces the production of pro-inflammatory cytokines and chemokines via reducing the binding of NF-κB to DNA. Imbalance between vasodilators (nitric oxide, NO and vasoconstrictors (endothelin, ET during I/R was shown to be the primary cause of liver microcirculation disturbance. Melatonin helps maintaining the stability of liver circulation and reduces hepatic injury during I/R through preventing alteration of the normal balance between ET and NO. The aim of this review was to explore the mechanisms of liver I/R injuries and the protective effects of melatonin against them.

  12. Furfural induces reactive oxygen species accumulation and cellular damage in Saccharomyces cerevisiae

    Slininger Patricia J

    2010-01-01

    Full Text Available Abstract Background Biofuels offer a viable alternative to petroleum-based fuel. However, current methods are not sufficient and the technology required in order to use lignocellulosic biomass as a fermentation substrate faces several challenges. One challenge is the need for a robust fermentative microorganism that can tolerate the inhibitors present during lignocellulosic fermentation. These inhibitors include the furan aldehyde, furfural, which is released as a byproduct of pentose dehydration during the weak acid pretreatment of lignocellulose. In order to survive in the presence of furfural, yeast cells need not only to reduce furfural to the less toxic furan methanol, but also to protect themselves and repair any damage caused by the furfural. Since furfural tolerance in yeast requires a functional pentose phosphate pathway (PPP, and the PPP is associated with reactive oxygen species (ROS tolerance, we decided to investigate whether or not furfural induces ROS and its related cellular damage in yeast. Results We demonstrated that furfural induces the accumulation of ROS in Saccharomyces cerevisiae. In addition, furfural was shown to cause cellular damage that is consistent with ROS accumulation in cells which includes damage to mitochondria and vacuole membranes, the actin cytoskeleton and nuclear chromatin. The furfural-induced damage is less severe when yeast are grown in a furfural concentration (25 mM that allows for eventual growth after an extended lag compared to a concentration of furfural (50 mM that prevents growth. Conclusion These data suggest that when yeast cells encounter the inhibitor furfural, they not only need to reduce furfural into furan methanol but also to protect themselves from the cellular effects of furfural and repair any damage caused. The reduced cellular damage seen at 25 mM furfural compared to 50 mM furfural may be linked to the observation that at 25 mM furfural yeast were able to exit the furfural

  13. RC-3095, a Selective Gastrin-Releasing Peptide Receptor Antagonist, Does Not Protect the Lungs in an Experimental Model of Lung Ischemia-Reperfusion Injury

    Vera L. Oliveira-Freitas

    2015-01-01

    Full Text Available RC-3095, a selective GRPR antagonist, has been shown to have anti-inflammatory properties in different models of inflammation. However, its protective effect on lungs submitted to lung ischemia-reperfusion injury has not been addressed before. Then, we administrated RC-3095 intravenously before and after lung reperfusion using an animal model of lung ischemia-reperfusion injury (LIRI by clamping the pulmonary hilum. Twenty Wistar rats were subjected to an experimental model in four groups: SHAM, ischemia-reperfusion (IR, RC-Pre, and RC-Post. The final mean arterial pressure significantly decreased in IR and RC-Pre compared to their values before reperfusion (P<0.001. The RC-Post group showed significant decrease of partial pressure of arterial oxygen at the end of the observation when compared to baseline (P=0.005. Caspase-9 activity was significantly higher in the RC-Post as compared to the other groups (P<0.013. No significant differences were observed in eNOS activity among the groups. The groups RC-Pre and RC-Post did not show any significant decrease in IL-1β (P=0.159 and TNF-α (P=0.260, as compared to IR. The histological score showed no significant differences among the groups. In conclusion, RC-3095 does not demonstrate a protective effect in our LIRI model. Additionally, its use after reperfusion seems to potentiate cell damage, stimulating apoptosis.

  14. Improvement of oxygen supply by an artificial carrier in combination with normobaric oxygenation decreases the volume of tissue hypoxia and tissue damage from transient focal cerebral ischemia

    Seiffge, David J.; Lapina, Natalia E.; Tsagogiorgas, Charalambos; Theisinger, Bastian; Henning, Robert H.; Schilling, Lothar

    Tissue hypoxia may play an important role in the development of ischemic brain damage. In the present study we investigated in a rat model of transient focal brain ischemia the neuroprotective effects of increasing the blood oxygen transport capacity by applying a semifluorinated alkane

  15. Dexrazoxane Shows No Protective Effect in the Acute Phase of Reperfusion during Myocardial Infarction in Pigs.

    Kamat, Pranitha; Vandenberghe, Stijn; Christen, Stephan; Bongoni, Anjan K; Meier, Bernhard; Rieben, Robert; Khattab, Ahmed A

    2016-01-01

    Calcium and iron overload participate in the mechanisms of ischemia/reperfusion (I/R) injury during myocardial infarction (MI). Calcium overload induces cardiomyocyte death by hypercontraction, while iron catalyses generation of reactive oxygen species (ROS). We therefore hypothesized that dexrazoxane, an intracellular metal chelator, would attenuate I/R injury. MI was induced in pigs by occlusion of the left anterior descending artery for 1 hour followed by 2 hours reperfusion. Thirty minutes before reperfusion either 5 mg/ml dexrazoxane (n = 5) or saline (n = 5) was infused intravenously. Myocardial necrosis as percentage of the area at ischemic risk was found to be similar in both groups (77.2 ± 18% for dexrazoxane and 76.4 ± 14% for saline group) as determined by triphenyl tetrazolium chloride staining of the ischemic myocardium. Also, serum levels of troponin-I were similar in both groups. A conductance catheter was used to measure left ventricular pressure and volume at all times. Markers for tissue damage due to ROS (HNE), endothelial cell activation (CD31) and inflammation (IgG, C3b/c, C5b9, MCP-1) were assessed on tissue and/or in serum. No significant differences were observed between the groups for the parameters analyzed. To conclude, in this clinically relevant model of early reperfusion after acute myocardial ischemia, dexrazoxane lacked attenuating effects on I/R injury as shown by the measured parameters.

  16. Dexrazoxane Shows No Protective Effect in the Acute Phase of Reperfusion during Myocardial Infarction in Pigs.

    Pranitha Kamat

    Full Text Available Calcium and iron overload participate in the mechanisms of ischemia/reperfusion (I/R injury during myocardial infarction (MI. Calcium overload induces cardiomyocyte death by hypercontraction, while iron catalyses generation of reactive oxygen species (ROS. We therefore hypothesized that dexrazoxane, an intracellular metal chelator, would attenuate I/R injury. MI was induced in pigs by occlusion of the left anterior descending artery for 1 hour followed by 2 hours reperfusion. Thirty minutes before reperfusion either 5 mg/ml dexrazoxane (n = 5 or saline (n = 5 was infused intravenously. Myocardial necrosis as percentage of the area at ischemic risk was found to be similar in both groups (77.2 ± 18% for dexrazoxane and 76.4 ± 14% for saline group as determined by triphenyl tetrazolium chloride staining of the ischemic myocardium. Also, serum levels of troponin-I were similar in both groups. A conductance catheter was used to measure left ventricular pressure and volume at all times. Markers for tissue damage due to ROS (HNE, endothelial cell activation (CD31 and inflammation (IgG, C3b/c, C5b9, MCP-1 were assessed on tissue and/or in serum. No significant differences were observed between the groups for the parameters analyzed. To conclude, in this clinically relevant model of early reperfusion after acute myocardial ischemia, dexrazoxane lacked attenuating effects on I/R injury as shown by the measured parameters.

  17. Comparison of the Protective Effects of Erythropoietin and Melatonin on Renal Ischemia-Reperfusion Injury.

    Banaei, Shokofeh; Ahmadiasl, Nasser; Alihemmati, Alireza

    2016-07-01

    Renal ischemia-reperfusion (IR) contributes to the development of acute renal failure (ARF). Oxygen free radicals are considered to be the principal components involved in the pathophysiological tissue alterations observed during renal IR. In this study, we compared the effects of melatonin (MEL) and erythropoietin (EPO), both known antioxidant and anti-inflammatory agents, on IR-induced renal injury in rats. Wistar albino rats were unilaterally nephrectomized and then subjected to 45 minutes of renal pedicle occlusion followed by 24 hours of reperfusion. MEL (10 mg/kg, i.p) and EPO (5000 U/kg, i.p) were administered prior to the onset of ischemia. After 24 hours of reperfusion and following decapitation, blood samples were collected for the determination of the hemoglobin (Hb) and hematocrit (Hct) levels. Additionally, renal samples were taken for histological evaluation. Ischemia-reperfusion significantly decreased the observed Hb and Hct values. The histopathological findings in the IR group confirmed that there was an increase in the hyaline cast and thickening of the Bowman capsule basement membrane. Treatment with EPO or MEL significantly increased the Hb and Hct values. In the MEL + IR group, the histopathological changes were lower than those found in the EPO + IR group. Treatment with EPO and MEL had a beneficial effect on renal IR injury. The results may also indicate that MEL protects against morphological damage better than EPO in renal IR injury.

  18. Atomic Oxygen Treatment Technique for Removal of Smoke Damage from Paintings

    Rutledge, S. K.; Banks, B. A.

    1997-01-01

    Soot deposits that can accumulate on surfaces of a painting during a fire can be difficult to clean from some types of paintings without damaging the underlying paint layers. A non-contact technique has been developed which can remove the soot by allowing a gas containing atomic oxygen to flow over the surface and chemically react with the soot to form carbon monoxide and carbon dioxide. The reaction is limited to the surface, so the underlying paint is not touched. The process can be controlled so that the cleaning can be stopped once the paint surface is reached. This paper describes the smoke exposure and cleaning of untreated canvas, acrylic gesso, and sections of an oil painting using this technique. The samples were characterized by optical microscopy and reflectance spectroscopy.

  19. The effects of sulforaphane on the liver and remote organ damage in hepatic ischemia-reperfusion model formed with pringle maneuver in rats.

    Oguz, Abdullah; Kapan, Murat; Kaplan, Ibrahim; Alabalik, Ulas; Ulger, Burak Veli; Uslukaya, Omer; Turkoglu, Ahmet; Polat, Yilmaz

    2015-06-01

    The purpose of this study was to investigate the effect of Sulforaphane on ischemia/ reperfusion (IR) injury of the liver and distant organs resulting from liver blood flow arrest. Fourty Wistar rats were assigned into four groups, each included 10 rats were used. Group I as only laparatomy, Group II laparatomy and Sulforaphane application, Group III hepatic IR; and Group IV as hepatic IR and Sulforaphane application group. Animals were subjected to liver ischemia for 30 min and then reperfusion is started. 5 mg/kg Sulforaphane was applied via oral lavage 15 minutes before initiating the experimental study. Blood samples were taken from the animals for biochemical analysis at 60th minutes of the experiment in the first and second groups; 30 minutes after beginning reperfusion in the third and forth groups. Simultaneously, liver, lung and kidney tissues were sampled for biochemical and histopathological examinations. The administration of sulforaphane significantly reduced the serum TOA and liver TOA levels, increased the serum TAC and liver TAC levels and also decreased The OSI and liver OSI levels. In the histopathologic examination, the injury was reduced by the administration of sulforaphane. Administration of sulforaphane did not lead to any significant changes in any parameter including histopathological parameters in both the kidney and the lung. Sulforaphane reduced the liver oxidative stress from I/R injury. A histological injury in liver was reduced by sulforaphane administration. However, there were no significant effects of sulforaphane on the remote organ injuries induced by IR. Copyright © 2015 IJS Publishing Group Limited. Published by Elsevier Ltd. All rights reserved.

  20. Regulation of radiation protective agents on cell damage induced by reactive oxygen species

    Kim, Jeong Hee; Lee, Si Eun; Ju, Eun Mi; Gao, Eu Feng [Kyung Hee University, Seoul (Korea)

    2002-04-01

    In this study, we developed candidates of new radio-protective agents and elucidated the regulation mechanism of these candidates on cell damage induced by reactive oxygen species. The methanol extracts and ethylacetate fractions of NP-1, NP-5, NP-7, NP-11, NP-12 and NP-14 showed higher radical scavenging activity. The extracts of NP-7, NP-12 and NP-14 showed strong protective effect against oxidative damage induced by UV and H{sub 2}O{sub 2}. The most of samples enhanced SOD, CAT and GPX activity in V79-4 cells. The protective effect of samples on H{sub 2}O{sub 2}-induced apoptosis was observed with microscope and flow cytometer. Cells exposed to H{sub 2}O{sub 2} exhibit distinct morphological features of programmed cell death, such as nuclear fragmentation and increase in the percentage of cells with a sub-G1 DNA content. However, cells which was pretreated with samples significantly reduced the characteristics of apoptotic cells. Their morphological observation and DNA profiles were similar to those of the control cells. NP-14 which had excellent antioxidant activity restored G2/M arrest induced by oxidative stress. These data suggested that natural medicinal plants protected H{sub 2}O{sub 2}-induced apoptosis. 42 refs., 29 figs., 11 tabs. (Author)

  1. Intestinal Ischaemia-Reperfusion Injury and Semen Characteristics ...

    olayemitoyin

    Nigeria. Summary: Increasing production of goats takes their reproductive ... of testicular damage and infertility and is a form of ischaemia-reperfusion injury. ... concentration, percentage of normal sperm cells, abnormal sperm cells and ...

  2. Reperfusion promotes mitochondrial dysfunction following focal cerebral ischemia in rats.

    Jun Li

    Full Text Available BACKGROUND AND PURPOSE: Mitochondrial dysfunction has been implicated in the cell death observed after cerebral ischemia, and several mechanisms for this dysfunction have been proposed. Reperfusion after transient cerebral ischemia may cause continued and even more severe damage to the brain. Many lines of evidence have shown that mitochondria suffer severe damage in response to ischemic injury. The purpose of this study was to observe the features of mitochondrial dysfunction in isolated mitochondria during the reperfusion period following focal cerebral ischemia. METHODS: Male Wistar rats were subjected to focal cerebral ischemia. Mitochondria were isolated using Percoll density gradient centrifugation. The isolated mitochondria were fixed for electron microscopic examination; calcium-induced mitochondrial swelling was quantified using spectrophotometry. Cyclophilin D was detected by Western blotting. Fluorescent probes were used to selectively stain mitochondria to measure their membrane potential and to measure reactive oxidative species production using flow cytometric analysis. RESULTS: Signs of damage were observed in the mitochondrial morphology after exposure to reperfusion. The mitochondrial swelling induced by Ca(2+ increased gradually with the increasing calcium concentration, and this tendency was exacerbated as the reperfusion time was extended. Cyclophilin D protein expression peaked after 24 hours of reperfusion. The mitochondrial membrane potential was decreased significantly during the reperfusion period, with the greatest decrease observed after 24 hours of reperfusion. The surge in mitochondrial reactive oxidative species occurred after 2 hours of reperfusion and was maintained at a high level during the reperfusion period. CONCLUSIONS: Reperfusion following focal cerebral ischemia induced significant mitochondrial morphological damage and Ca(2+-induced mitochondrial swelling. The mechanism of this swelling may be mediated by

  3. Organ-Protective Effects of Red Wine Extract, Resveratrol, in Oxidative Stress-Mediated Reperfusion Injury

    Fu-Chao Liu

    2015-01-01

    Full Text Available Resveratrol, a polyphenol extracted from red wine, possesses potential antioxidative and anti-inflammatory effects, including the reduction of free radicals and proinflammatory mediators overproduction, the alteration of the expression of adhesion molecules, and the inhibition of neutrophil function. A growing body of evidence indicates that resveratrol plays an important role in reducing organ damage following ischemia- and hemorrhage-induced reperfusion injury. Such protective phenomenon is reported to be implicated in decreasing the formation and reaction of reactive oxygen species and pro-nflammatory cytokines, as well as the mediation of a variety of intracellular signaling pathways, including the nitric oxide synthase, nicotinamide adenine dinucleotide phosphate oxidase, deacetylase sirtuin 1, mitogen-activated protein kinase, peroxisome proliferator-activated receptor-gamma coactivator 1 alpha, hemeoxygenase-1, and estrogen receptor-related pathways. Reperfusion injury is a complex pathophysiological process that involves multiple factors and pathways. The resveratrol is an effective reactive oxygen species scavenger that exhibits an antioxidative property. In this review, the organ-protective effects of resveratrol in oxidative stress-related reperfusion injury will be discussed.

  4. Mobile phone radiation induces reactive oxygen species production and DNA damage in human spermatozoa in vitro.

    Geoffry N De Iuliis

    Full Text Available BACKGROUND: In recent times there has been some controversy over the impact of electromagnetic radiation on human health. The significance of mobile phone radiation on male reproduction is a key element of this debate since several studies have suggested a relationship between mobile phone use and semen quality. The potential mechanisms involved have not been established, however, human spermatozoa are known to be particularly vulnerable to oxidative stress by virtue of the abundant availability of substrates for free radical attack and the lack of cytoplasmic space to accommodate antioxidant enzymes. Moreover, the induction of oxidative stress in these cells not only perturbs their capacity for fertilization but also contributes to sperm DNA damage. The latter has, in turn, been linked with poor fertility, an increased incidence of miscarriage and morbidity in the offspring, including childhood cancer. In light of these associations, we have analyzed the influence of RF-EMR on the cell biology of human spermatozoa in vitro. PRINCIPAL FINDINGS: Purified human spermatozoa were exposed to radio-frequency electromagnetic radiation (RF-EMR tuned to 1.8 GHz and covering a range of specific absorption rates (SAR from 0.4 W/kg to 27.5 W/kg. In step with increasing SAR, motility and vitality were significantly reduced after RF-EMR exposure, while the mitochondrial generation of reactive oxygen species and DNA fragmentation were significantly elevated (P<0.001. Furthermore, we also observed highly significant relationships between SAR, the oxidative DNA damage bio-marker, 8-OH-dG, and DNA fragmentation after RF-EMR exposure. CONCLUSIONS: RF-EMR in both the power density and frequency range of mobile phones enhances mitochondrial reactive oxygen species generation by human spermatozoa, decreasing the motility and vitality of these cells while stimulating DNA base adduct formation and, ultimately DNA fragmentation. These findings have clear implications

  5. Radiation-induced DNA damage in tumors and normal tissues. II. Influence of dose, residual DNA damage and physiological factors in oxygenated cells

    Zhang, H.; Wheeler, K.T.

    1994-01-01

    Detection and quantification of hypoxic cells in solid tumors is important for many experimental and clinical situations. Several laboratories, including ours, have suggested that assays which measure radiation-induced DNA strand breaks and DNA-protein crosslinks (DPCs) might be used to detect or quantify hypoxic cells in tumors and normal tissues. Recently, we demonstrated the feasibility of using an alkaline elution assay that measures strand breaks and DPCs to detect and/or quantify hypoxic cells in tissues. For this approach to be valid, DPCs must not be formed to any great extent in irradiated oxygenated cells, and the formation and repair of strand breaks and DPCs in oxygenated cells must not be modified appreciably by physiological factors (e.g., temperature, pH and nutrient depletion) that are often found in solid tumors. To address these issues, two sets of experiments were performed. In one set of experiments, oxygenated 9L cells in tissue culture, subcutaneous 9L tumors and rat cerebella were irradiated with doses of 15 or 50 Gy and allowed to repair until the residual strand break damage was low enough to detect DPCs. In another set of experiments, oxygenated exponentially growing or plateau-phase 9L cells in tissue culture were irradiated with a dose of 15 Gy at 37 or 20 degrees C, while the cells were maintained at a pH of either 6.6 or 7.3. DNA-protein crosslinks were formed in oxygenated cells about 100 times less efficiently than in hypoxic cells. In addition, temperature, pH, nutrient depletion and growth phase did not appreciably alter the formation and repair of strand breaks or the formation of DPCs in oxygenated 9L cells. These results support the use of this DNA damage assay for the detection and quantification of hypoxic cells in solid tumors. 27 refs., 5 tabs

  6. Antioxidant enzyme expression and reactive oxygen species damage in prostatic intraepithelial neoplasia and cancer.

    Bostwick, D G; Alexander, E E; Singh, R; Shan, A; Qian, J; Santella, R M; Oberley, L W; Yan, T; Zhong, W; Jiang, X; Oberley, T D

    2000-07-01

    Oxidative stress results in damage to cellular structures and has been linked to many diseases, including cancer. The authors sought to determine whether the expression of three major antioxidant enzymes, copper-zinc superoxide dismutase (SOD1), manganese superoxide dismutase (SOD2), and catalase, was altered in human prostate carcinoma and its likely precursor, high grade prostatic intraepithelial neoplasia (PIN). The level of reactive oxygen species damage was evaluated by measuring the expression of the DNA adduct 8-hydroxydeoxyguanosine. The authors evaluated the tissue expression of the antioxidant enzymes in prostate carcinoma by immunohistochemistry, immunogold electron microscopy, and enzymatic assay. The polymerase chain reaction was used to amplify and screen tissue specimens for the genes of SOD1, SOD2, and extracellular SOD (SOD3). Matched paraffin embedded tissue sections were evaluated by RNA in situ hybridization for expression of SOD1 and immunohistochemically for the DNA adduct 8-hydroxydeoxyguanosine. All prostatic tissues, including cancer, displayed immunoreactivity for the three antioxidant enzymes in epithelial cells, with no staining of the stroma, inflammatory cells, or endothelial cells. The number of immunoreactive cells was greater in benign epithelium than in PIN and cancer for each enzyme. The mean percentage and intensity of immunoreactive cells was greatest for SOD2, intermediate for SOD1, and lower for catalase. Staining in cancer was heterogeneous. Immunogold ultrasound studies revealed strong mitochondrial labeling for SOD2, which was greater in benign epithelium than in cancer; SOD1 labeling was invariably weaker, with nuclear labeling in benign epithelium and cytoplasmic labeling in cancer cells. There was no difference in enzyme activity for the three antioxidant enzymes between benign epithelium and cancer. No mutations were found in the 5 exons of SOD1, 5 exons of SOD2, and 3 exons of SOD3, except for 3 of 20 cases with

  7. Effects of calcium antagonist and free radical scavengers on ischemic and reperfused myocardium due to acute occlusion of coronary arteries

    Ohsuzu, Fumitaka; Sakata, Nobuhiro; Yanagida, Shigeki

    1988-01-01

    The Langendorff perfused rat heart was used to investigate whether ischemic and reperfused injury could be protected by anti-free radical intervention alone or combined treatment with calcium antagonist. Hearts were subjected to 10 min. of aerobic perfusion with Krebs-Henseleit solution (K-H) and then randomized into three groups (GP): Control group received only K-H, FRS group K-H with superoxide dismutase (24 IU/ml) and catalase (22 IU/ml) and Combined group the same solution of FRS group with verapamil (10'-'7M) for 10 min; and three groups were subjected to 20 min. of global ischemia; and each group was reperfused by the prior perfusate for 20 min. LV developed pressure (DP) and heart rate (HR) were measured by an intraventricular baloon. Phosphorus-31 NMR spectroscopy allowed continuous monitoring of myocardial phosphocreatine (PCr), inorganic phosphate (Pi) and β-ATP content. Each group consisted of 5 experiments. PCr in Combined group was significantly higher than that of Control group with significantly higher values of DP and DPxHR compared to Combined group in the early phase of ischemia. By the middle phase of reperfusion, significant reduction in Pi was found only in Combined group with the reduction of HR. However, no significant difference of β-ATP was found between Control group and Combined group through ischemia and reperfusion. These results suggest that free radical scavengers alone could not protect ischemic and reperfused myocardium from injury, but that the reduction of oxygen consumption by verapamil might be predominantly effective in preventing myocardial damage partially from ischemia and reperfusion. (author)

  8. Lung transplantation for idiopathic pulmonary arterial hypertension on intraoperative and postoperatively prolonged extracorporeal membrane oxygenation provides optimally controlled reperfusion and excellent outcome.

    Moser, Bernhard; Jaksch, Peter; Taghavi, Shahrokh; Muraközy, Gabriella; Lang, Georg; Hager, Helmut; Krenn, Claus; Roth, Georg; Faybik, Peter; Bacher, Andreas; Aigner, Clemens; Matilla, José R; Hoetzenecker, Konrad; Hacker, Philipp; Lang, Irene; Klepetko, Walter

    2018-01-01

    Lung transplantation for idiopathic pulmonary arterial hypertension has the highest reported postoperative mortality of all indications. Reasons lie in the complexity of treatment of these patients and the frequent occurrence of postoperative left ventricular failure. Transplantation on intraoperative extracorporeal membrane oxygenation support instead of cardiopulmonary bypass and even more the prolongation of extracorporeal membrane oxygenation into the postoperative period helps to overcome these problems. We reviewed our experience with this concept. All patients undergoing bilateral lung transplantation for idiopathic pulmonary arterial hypertension on intraoperative extracorporeal membrane oxygenation with or without prophylactic extracorporeal membrane oxygenation prolongation into the postoperative period between January 2000 and December 2014 were retrospectively analysed. Forty-one patients entered the study. Venoarterial extracorporeal membrane oxygenation support was prolonged into the postoperative period for a median of 2.5 days (range 1-40). Ninety-day, 1-, 3- and 5-year survival rates for the patient collective were 92.7%, 90.2%, 87.4% and 87.4%, respectively. When compared with 31 patients with idiopathic pulmonary arterial hypertension transplanted in the same period of time without prolongation of extracorporeal membrane oxygenation into the postoperative period, the results compared favourably (83.9%, 77.4%, 77.4%, and 77.4%; P = 0.189). Furthermore, these results are among the best results ever reported for this particularly difficult patient population. Bilateral lung transplantation for idiopathic pulmonary arterial hypertension with intraoperative venoarterial extracorporeal membrane oxygenation support seems to provide superior outcome compared with the results reported about the use of cardiopulmonary bypass. Prophylactic prolongation of venoarterial extracorporeal membrane oxygenation into the early postoperative period provides

  9. Green synthesized silver nanoparticles destroy multidrug resistant bacteria via reactive oxygen species mediated membrane damage

    Balaram Das

    2017-09-01

    Full Text Available The growing need of antimicrobial agent for novel therapies against multi-drug resistant bacteria has drawn researchers to green nanotechnology. Especially, eco-friendly biosynthesis of silver nanoparticles (Ag NPs has shown its interesting impact against bacterial infection in laboratory research. In this study, a simple method was developed to form Ag NPs at room temperature, bio-reduction of silver ions from silver nitrate salt by leaf extract from Ocimum gratissimum. The Ag NPs appear to be capped with plant proteins, but are otherwise highly crystalline and pure. The Ag NPs have a zeta potential of −15 mV, a hydrodynamic diameter of 31 nm with polydispersity index of 0.65, and dry sizes of 18 ± 3 nm and 16 ± 2 nm, based on scanning and transmission electron microscopy respectively. The minimum inhibitory concentration (MIC of the Ag NPs against a multi-drug resistant Escherichia coli was 4 μg/mL and the minimum bactericidal concentration (MBC was 8 μg/mL, while the MIC and MBC against a resistant strain of Staphylococcus aureus were slightly higher at 8 μg/mL and 16 μg/mL respectively. Further, the Ag NPs inhibited biofilm formation by both Escherichia coli and S. aureus at concentrations similar to the MIC for each strain. Treatment of E. coli and S. aureus with Ag NPs resulted in damage to the surface of the cells and the production of reactive oxygen species. Both mechanisms likely contribute to bacterial cell death. In summary, this new method appears promising for green biosynthesis of pure Ag NPs with potent antimicrobial activity.

  10. Molecular pathways involved in the early and late damage induced by testis ischemia: evidence for a rational pharmacological modulation.

    Altavilla, D; Romeo, C; Squadrito, F; Marini, H; Morgia, G; Antonuccio, P; Minutoli, L

    2012-01-01

    Testicular torsion or torsion of the spermatic cord is a surgical emergency in which misdiagnosis and inappropriate treatment can lead to male infertility. Events occurring during testicular torsion and detorsion are representative of an ischemia-reperfusion injury observed in other organs. The two most important factors determining testicular damage are the degree of twisting and the early onset of a surgical treatment to counter-rotate both testis and spermatic cord for inducing reperfusion. The damage from reperfusion is more severe than that induced by ischemia and several mechanisms are implicated in the development of testicular damage following torsion and detorsion. However, these mechanisms have not yet been fully clarified and, as a consequence, there is still a strong need to identify specific pharmacological treatment to limit the damage triggered by the reperfusion procedures. Ischemia and reperfusion of testis result in elevated production of reactive oxygen species (ROS), activate mitogen activated protein kinases (MAPKs) and PPARβ/δ receptor, induce transcription factors and growth factors including NF-κB and VEGF, trigger apoptotic machinery and induce several inflammatory cytokines, including TNF-α and IL-1β . This pathological cascade is responsible for the testicular atrophy, decreased blood flow and impaired spermatogenesis. Several pharmacological approaches have been characterized as promising therapeutic agents for the management of testicular torsion and may be useful to ameliorate the sequel of this disease.

  11. An Atmospheric Atomic Oxygen Source for Cleaning Smoke Damaged Art Objects

    Banks, Bruce A.; Rutledge, Sharon K.; Norris, Mary Jo

    1998-01-01

    Soot and other carbonaceous combustion products deposited on the surfaces of porous ceramic, stone, ivory and paper can be difficult to remove and can have potentially unsatisfactory results using wet chemical and/or abrasive cleaning techniques. An atomic oxygen source which operates in air at atmospheric pressure, using a mixture of oxygen and helium, has been developed to produce an atomic oxygen beam which is highly effective in oxidizing soot deposited on surfaces by burning candles made of paraffin, oil or rendered animal fat. Atomic oxygen source operating conditions and the results of cleaning soot from paper, gesso, ivory, limestone and water color-painted limestone are presented,

  12. Electroacupuncture ameliorates post-stroke learning and memory through minimizing ultrastructural brain damage and inhibiting the expression of MMP-2 and MMP-9 in cerebral ischemia-reperfusion injured rats.

    Lin, Ruhui; Yu, Kunqiang; Li, Xiaojie; Tao, Jing; Lin, Yukun; Zhao, Congkuai; Li, Chunyan; Chen, Li-Dian

    2016-07-01

    The aim of the present study was to investigate the potential neuroprotective effects of electroacupuncture (EA) in the treatment of cerebral ischemia/reperfusion (I/R) injury, and to elucidate the association between this neuroprotective effect and brain ultrastructure and expression of matrix metalloproteinase (MMP)‑2 and 9. Rats underwent focal cerebral I/R injury by arterial ligation and received in vivo therapeutic EA at the Baihui (DU20) and Shenting (DU24) acupoints. The therapeutic efficacy was then evaluated following the surgery. The results of the current study demonstrated that EA treatment significantly ameliorated neurological deficits and reduced cerebral infarct volume compared with I/R injured rats. Furthermore, EA improved the learning and memory ability of rats following I/R injury, inhibited blood brain barrier breakdown and reduced neuronal damage in the ischemic penumbra. Furthermore, EA attenuated ultrastructural changes in the brain tissue following ischemia and inhibited MMP‑2/MMP‑9 expression in cerebral I/R injured rats. The results suggest that EA ameliorates anatomical deterioration, and learning and memory deficits in rats with cerebral I/R injury.

  13. Effects Of Ischemic Preconditioning On The Renal Ischemia- Reperfusion Injury

    Anyamanesh S

    2003-07-01

    Full Text Available  During kidney and other organ transplantation, the organ to be transplanted, must inevitably remain out of the body with little or no blood perfusion at all for a long period of time (ischemia. These events have been suggested to cause the formation of oxygen- derived free radicals (OFR. Reperfusion (reintroduction of blood flow will further exacerbate the initial damage caused by the ischemic insult and may result in the production of free radicals. The aim of this study was to investigate whether induction of brief periods of renal artery occlusion (ischemic pre¬conditioning, IPC can provide protection from the effects of a subsequent period of ischemia and reperfusion (IR in the rat kidney."nMaterials and Methods: In this regard, 28 white, male rats were randomly and equally divided into four groups: Control (sham- operated, IPC alone, IR alone (30 min ischemia followed by 10 min reperfusion, and IPC- IR. Preconditioning involved the sequential clamping of the right renal artery for 5 min and declamping for 5 min for a total of 3 cycles. To demonstrate the effectiveness of IPC regimen, vitamin E as an endogenous antioxidant and an index of lipid peroxidation was measured by HPLC after its extraction from right renal venous plasma and right renal tissue."nResults: Results of this study showed that the amount of vitamin E of renal tissue and venous plasma in the IR group had a significant decrease when compared to the control group (P< 0.0001. Whereas the amount of this vitamin in both renal tissue and venous plasma of the IPC- IR group was significantly higher than that in the IR group (P< 0.0001, but did not show any significant difference with the control group."nConclusion: In this study, preconditioning method prevented the reduction of the endogenous antioxidant (Vit. E in encountering the following sustained ischemic insult. Therefore, we suggest that ischemic preconditioning can be used to protect the Vit. E level of kidney from its

  14. White Matter Damage Relates to Oxygen Saturation in Children With Sickle Cell Anemia Without Silent Cerebral Infarcts.

    Kawadler, Jamie M; Kirkham, Fenella J; Clayden, Jonathan D; Hollocks, Matthew J; Seymour, Emma L; Edey, Rosanna; Telfer, Paul; Robins, Andrew; Wilkey, Olu; Barker, Simon; Cox, Tim C S; Clark, Chris A

    2015-07-01

    Sickle cell anemia is associated with compromised oxygen-carrying capability of hemoglobin and a high incidence of overt and silent stroke. However, in children with no evidence of cerebral infarction, there are changes in brain morphometry relative to healthy controls, which may be related to chronic anemia and oxygen desaturation. A whole-brain tract-based spatial statistics analysis was carried out in 25 children with sickle cell anemia with no evidence of abnormality on T2-weighted magnetic resonance imaging (13 male, age range: 8-18 years) and 14 age- and race-matched controls (7 male, age range: 10-19 years) to determine the extent of white matter injury. The hypotheses that white matter damage is related to daytime peripheral oxygen saturation and steady-state hemoglobin were tested. Fractional anisotropy was found to be significantly lower in patients in the subcortical white matter (corticospinal tract and cerebellum), whereas mean diffusivity and radial diffusivity were higher in patients in widespread areas. There was a significant negative relationship between radial diffusivity and oxygen saturation (Plevel negative relationship between radial diffusivity and hemoglobin (Pcell anemia, and provides for the first time direct evidence of a relationship between brain microstructure and markers of disease severity (eg, peripheral oxygen saturation and steady-state hemoglobin). This study suggests that diffusion tensor imaging metrics may serve as a biomarker for future trials of reducing hypoxic exposure. © 2015 American Heart Association, Inc.

  15. Evaluation of N-acetylcysteine and methylprednisolone as therapies for oxygen and acrolein-induced lung damage

    Critchley, J.A.J.H. (Univ. of Edinburgh (England)); Beeley, J.M.; Clark, R.J.; Buchanan, J.D. (Royal Naval Hospital Hoslar, Gosport (England)); Summerfield, M.; Bell, S. (Admiralty Research Establishment, Alverstoke (England)); Spurlock, M.S.; Edginton, J.A.G. (Chemical Defence Establishment, Porton Down (England))

    1990-04-01

    Reactive oxidizing species are implicated in the etiology of a range of inhalational pulmonary injuries. Consequently, various free radical scavengers have been tested as potential prophylactic agents. The sulfydryl compound, N-acetylcysteine (NAC) is the only such compound clinically available for use in realistic dosages, and it is well established as an effective antidote for the hepatic and renal toxicity of paracetamol. Another approach in pulmonary injury prophylaxis is methylprednisolone therapy. The authors evaluated NAC and methylprednisolone in two rats models of inhalation injury: 40-hr exposure to >97% oxygen at 1.1 bar and 15-min exposure to acrolein vapor (210 ppm). The increases in lung wet/dry weight ratios, seen with both oxygen and acrolein toxicity were reduced with both treatments. However, with oxygen, NAC therapy was associated with considerably increased mortality and histological changes. Furthermore, IP NAC administration resulted in large volumes of ascitic fluid. With acrolein, IV, NAC had no significant effect on mortality or pulmonary histological damage. Methylprednisolone had no beneficial effects on either the mortality or histological damage observed in either toxicity model. They caution against the ad hoc use of NAC in the management of inhalational pulmonary injury.

  16. Oxidative damage of U937 human leukemic cells caused by hydroxyl radical results in singlet oxygen formation.

    Marek Rác

    Full Text Available The exposure of human cells to oxidative stress leads to the oxidation of biomolecules such as lipids, proteins and nuclei acids. In this study, the oxidation of lipids, proteins and DNA was studied after the addition of hydrogen peroxide and Fenton reagent to cell suspension containing human leukemic monocyte lymphoma cell line U937. EPR spin-trapping data showed that the addition of hydrogen peroxide to the cell suspension formed hydroxyl radical via Fenton reaction mediated by endogenous metals. The malondialdehyde HPLC analysis showed no lipid peroxidation after the addition of hydrogen peroxide, whereas the Fenton reagent caused significant lipid peroxidation. The formation of protein carbonyls monitored by dot blot immunoassay and the DNA fragmentation measured by comet assay occurred after the addition of both hydrogen peroxide and Fenton reagent. Oxidative damage of biomolecules leads to the formation of singlet oxygen as conformed by EPR spin-trapping spectroscopy and the green fluorescence of singlet oxygen sensor green detected by confocal laser scanning microscopy. It is proposed here that singlet oxygen is formed by the decomposition of high-energy intermediates such as dioxetane or tetroxide formed by oxidative damage of biomolecules.

  17. Substrate use in ischemic and reperfused canine myocardium: quantitative considerations

    Myears, D.W.; Sobel, B.E.; Bergmann, S.R.

    1987-01-01

    The patterns of use of substrate in reperfused myocardium are not yet well elucidated, and their delineation is essential for adequate interpretation of results of analyses performed after positron emission tomography with labeled substrates to differentiate normal from abnormal heart muscle. Accordingly, in open-chest, anesthetized dogs the authors measured glucose and fatty acid utilization in normal, ischemic, and reperfused myocardium and assessed the contributions of metabolism of each substrate to overall oxidative metabolism. Intracoronary [ 3 H]glucose and [ 14 C]palmitate were administered in five control dogs, eight dogs subjected to 1 h of coronary occlusion, and nine dogs subjected to reperfusion after 1 h of ischemia. Regional coronary venous blood samples were assayed sequentially. In reperfused myocardium, utilization of glucose was 103% greater than that in ischemic and 273% greater than in normal myocardium. Utilization of fatty acid during reperfusion, although greater than that in ischemic myocardium, was significantly less than that in normal myocardium despite restoration of flow to 80% of control values. Despite diminished net uptake of fatty acid, oxidation of fatty acid accounted for 63% of total oxygen consumption in reperfused myocardium. These studies indicate that canine myocardium reperfused after 1 h of ischemia exhibits enhanced uptake of glucose and impaired utilization of palmitate. Nevertheless, palmitate continues to comprise the substrate primarily utilized for oxidative metabolism

  18. Vorinostat induces reactive oxygen species and DNA damage in acute myeloid leukemia cells.

    Luca A Petruccelli

    Full Text Available Histone deacetylase inhibitors (HDACi are promising anti-cancer agents, however, their mechanisms of action remain unclear. In acute myeloid leukemia (AML cells, HDACi have been reported to arrest growth and induce apoptosis. In this study, we elucidate details of the DNA damage induced by the HDACi vorinostat in AML cells. At clinically relevant concentrations, vorinostat induces double-strand breaks and oxidative DNA damage in AML cell lines. Additionally, AML patient blasts treated with vorinostat display increased DNA damage, followed by an increase in caspase-3/7 activity and a reduction in cell viability. Vorinostat-induced DNA damage is followed by a G2-M arrest and eventually apoptosis. We found that pre-treatment with the antioxidant N-acetyl cysteine (NAC reduces vorinostat-induced DNA double strand breaks, G2-M arrest and apoptosis. These data implicate DNA damage as an important mechanism in vorinostat-induced growth arrest and apoptosis in both AML cell lines and patient-derived blasts. This supports the continued study and development of vorinostat in AMLs that may be sensitive to DNA-damaging agents and as a combination therapy with ionizing radiation and/or other DNA damaging agents.

  19. Vorinostat Induces Reactive Oxygen Species and DNA Damage in Acute Myeloid Leukemia Cells

    Pettersson, Filippa; Retrouvey, Hélène; Skoulikas, Sophia; Miller, Wilson H.

    2011-01-01

    Histone deacetylase inhibitors (HDACi) are promising anti-cancer agents, however, their mechanisms of action remain unclear. In acute myeloid leukemia (AML) cells, HDACi have been reported to arrest growth and induce apoptosis. In this study, we elucidate details of the DNA damage induced by the HDACi vorinostat in AML cells. At clinically relevant concentrations, vorinostat induces double-strand breaks and oxidative DNA damage in AML cell lines. Additionally, AML patient blasts treated with vorinostat display increased DNA damage, followed by an increase in caspase-3/7 activity and a reduction in cell viability. Vorinostat-induced DNA damage is followed by a G2-M arrest and eventually apoptosis. We found that pre-treatment with the antioxidant N-acetyl cysteine (NAC) reduces vorinostat-induced DNA double strand breaks, G2-M arrest and apoptosis. These data implicate DNA damage as an important mechanism in vorinostat-induced growth arrest and apoptosis in both AML cell lines and patient-derived blasts. This supports the continued study and development of vorinostat in AMLs that may be sensitive to DNA-damaging agents and as a combination therapy with ionizing radiation and/or other DNA damaging agents. PMID:21695163

  20. Impact of Chronic Neonatal Intermittent Hypoxia on Severity of Retinal Damage in a Rat Model of Oxygen-Induced Retinopathy.

    Beharry, Kay D; Cai, Charles L; Ahmad, Taimur; Guzel, Sibel; Valencia, Gloria B; Aranda, Jacob V

    2018-01-01

    Neonatal intermittent hypoxia (IH) followed by re-oxygenation in normoxia or supplemental oxygen (IHR) increases the risk for severe retinopathy of prematurity (ROP). The exact timing for the onset of retinal damage which may guide strategic interventions during retinal development, is unknown. We tested the hypothesis that chronic exposure of the immature retina to neonatal IH induces early manifestations of retinal damage that can be utilized as key time points for strategic pharmacologic intervention. Newborn rats were exposed to IH within 2 hours of birth (P0) until P14, or allowed to recover in room air (RA) from P14 to P21 (IHR). Retinal integrity and angiogenesis biomarkers were progressively assessed before (P0), during IH, and post IH (recovery in RA), or IHR, and compared to normoxic age-matched controls. Retinal damage occurred as early as day 3 of neonatal IH, consistent with vascular abnormalities and disturbances in the astrocytic template. These abnormalities worsened during IHR. Pharmacologic and non-pharmacologic interventions to identify, prevent, or minimize neonatal IH should be implemented shortly after birth in high risk preterm newborns. This strategy may lead to a reduction in the outcome of severe ROP requiring later invasive treatments.

  1. Attenuating brain inflammation, ischemia, and oxidative damage by hyperbaric oxygen in diabetic rats after heat stroke

    Kai-Li Lee

    2013-08-01

    Conclusion: Our results suggest that, in diabetic animals, HBO2 therapy may improve outcomes of HS in part by reducing heat-induced activated inflammation and ischemic and oxidative damage in the hypothalamus and other brain regions.

  2. Electromagnetic noise inhibits radiofrequency radiation-induced DNA damage and reactive oxygen species increase in human lens epithelial cells

    Wu, Wei; Wang, KaiJun; Ni, Shuang; Ye, PanPan; Yu, YiBo; Ye, Juan; Sun, LiXia

    2008-01-01

    Purpose The goal of this study was to investigate whether superposing of electromagnetic noise could block or attenuate DNA damage and intracellular reactive oxygen species (ROS) increase of cultured human lens epithelial cells (HLECs) induced by acute exposure to 1.8 GHz radiofrequency field (RF) of the Global System for Mobile Communications (GSM). Methods An sXc-1800 RF exposure system was used to produce a GSM signal at 1.8 GHz (217 Hz amplitude-modulated) with the specific absorption rate (SAR) of 1, 2, 3, and 4 W/kg. After 2 h of intermittent exposure, the ROS level was assessed by the fluorescent probe, 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA). DNA damage to HLECs was examined by alkaline comet assay and the phosphorylated form of histone variant H2AX (γH2AX) foci formation assay. Results After exposure to 1.8 GHz RF for 2 h, HLECs exhibited significant intracellular ROS increase in the 2, 3, and 4 W/kg groups. RF radiation at the SAR of 3 W/kg and 4 W/kg could induce significant DNA damage, examined by alkaline comet assay, which was used to detect mainly single strand breaks (SSBs), while no statistical difference in double strand breaks (DSBs), evaluated by γH2AX foci, was found between RF exposure (SAR: 3 and 4 W/kg) and sham exposure groups. When RF was superposed with 2 μT electromagnetic noise could block RF-induced ROS increase and DNA damage. Conclusions DNA damage induced by 1.8 GHz radiofrequency field for 2 h, which was mainly SSBs, may be associated with the increased ROS production. Electromagnetic noise could block RF-induced ROS formation and DNA damage. PMID:18509546

  3. Measurement of ischaemia-reperfusion in patients with intermittent claudication using NMR-based metabonomics.

    Coolen, S.A.; Daykin, C.A.; Duynhoven, J.P. van; Dorsten, F.A. van; Wulfert, F.; Mathot, J.; Scheltinga, M.R.M.; Stroosma, O.; Vader, H.L.; Wijnen, M.H.W.A.

    2008-01-01

    Intermittent claudication has proved to be a good in vivo model for ischaemia-reperfusion. For assessment of ischaemia-reperfusion damage, the known biochemical markers all have disadvantages with respect to sensitivity and interference with other physiological events. In this work, we studied the

  4. Influence of post-deposition treatment by UV light and oxygen (ozone) on 350 nm damage thresholds of SiO2 films deposited from sols

    Thomas, I.; Wilder, J.; Lee, A.; George, D.

    1988-01-01

    Certain multilayer porous silica AR coatings on fused silica substrates prepared by the sol-gel process have been found to have a much lower laser damage threshold than single layer coatings prepared by the same method. Treatment with UV light in the presence of oxygen (which gives ozone) at low temperature was found to restore damage thresholds to the levels found in single layers. Damage thresholds were measured at 350 nm with a 25 ns pulse for 1000 shots at 25 Hz. The effect of exposure time and other factors such as replacement of oxygen with nitrogen and vacuum are described

  5. Trauma hemostasis and oxygenation research position paper on remote damage control resuscitation: definitions, current practice, and knowledge gaps.

    Jenkins, Donald H; Rappold, Joseph F; Badloe, John F; Berséus, Olle; Blackbourne, Lorne; Brohi, Karim H; Butler, Frank K; Cap, Andrew P; Cohen, Mitchell Jay; Davenport, Ross; DePasquale, Marc; Doughty, Heidi; Glassberg, Elon; Hervig, Tor; Hooper, Timothy J; Kozar, Rosemary; Maegele, Marc; Moore, Ernest E; Murdock, Alan; Ness, Paul M; Pati, Shibani; Rasmussen, Todd; Sailliol, Anne; Schreiber, Martin A; Sunde, Geir Arne; van de Watering, Leo M G; Ward, Kevin R; Weiskopf, Richard B; White, Nathan J; Strandenes, Geir; Spinella, Philip C

    2014-05-01

    The Trauma Hemostasis and Oxygenation Research Network held its third annual Remote Damage Control Resuscitation Symposium in June 2013 in Bergen, Norway. The Trauma Hemostasis and Oxygenation Research Network is a multidisciplinary group of investigators with a common interest in improving outcomes and safety in patients with severe traumatic injury. The network's mission is to reduce the risk of morbidity and mortality from traumatic hemorrhagic shock, in the prehospital phase of resuscitation through research, education, and training. The concept of remote damage control resuscitation is in its infancy, and there is a significant amount of work that needs to be done to improve outcomes for patients with life-threatening bleeding secondary to injury. The prehospital phase of resuscitation is critical in these patients. If shock and coagulopathy can be rapidly identified and minimized before hospital admission, this will very likely reduce morbidity and mortality. This position statement begins to standardize the terms used, provides an acceptable range of therapeutic options, and identifies the major knowledge gaps in the field.

  6. Downregulation of Lung Toll-Like Receptor 4 Could Effectively Attenuate Liver Transplantation-Induced Pulmonary Damage at the Early Stage of Reperfusion

    Xinjin Chi

    2015-01-01

    Full Text Available Acute lung injury (ALI is a severe complication of orthotopic liver transplantation (OLT with unclear underline mechanism. Toll-like receptor 4 (TLR4 has been identified as a key receptor mediating inflammation. We hypothesized that TLR4-mediated pulmonary inflammation may contribute to development of ALI during OLT. Patients with or without ALI were observed for serum cytokines and expression of TLR4 on peripheral blood polymorphonuclear leukocytes (PMNs. Next, rats which underwent orthotopic autologous liver transplantation (OALT were divided into sham and model groups. Pulmonary function and the level of TLR4 expression and cytokines were analyzed. Furthermore, the role of TLR4 in OALT-mediated ALI was assessed in rats treated with TLR4-siRNA before OALT. The PMNs TLR4 expression and the serum TNF-α and IL-β level were higher in patients with ALI than those with non-ALI. Interestingly, lung TLR4 expression was significantly increased after 8 hours of OALT with increased levels of TNF-α and IL-β, which lead to lung pathological damage and an increase of lung myeloperoxidase content. Moreover, knockdown of TLR4 reduced lung cytokines release and reversed the above pathologic changes after OALT and finally improved rats’ survival rate. In conclusion, TLR4 overexpression, potentially by stimulating proinflammatory cytokine overproduction, contributes to the development of ALI after OLT.

  7. NMDA receptor dependent PGC-1alpha up-regulation protects the cortical neuron against oxygen-glucose deprivation/reperfusion injury.

    Luo, Yun; Zhu, Wenjing; Jia, Jia; Zhang, Chenyu; Xu, Yun

    2009-09-01

    The peroxisome proliferator activated receptor coactivator 1 alpha (PGC-1alpha) is a nuclear transcriptional coactivator that is widely expressed in the brain areas. Over-expression of PGC-1alpha can protect neuronal cells from oxidant-induced injury. The purpose of the current study is to investigate the role of PGC-1alpha in the oxygen (anoxia) deprivation (OGD) neurons. The PGC-1alpha mRNA and protein level between control and OGD neurons were examined by real-time PCR and Western blot. More PGC-1alpha expression was found in the OGD neurons compared with the normal group. Over-expression of PGC-1alpha suppressed cell apoptosis while inhibition of the PGC-1alpha expression induced cell apoptosis in OGD neurons. Furthermore, increase of PGC-1alpha resulted in activation of N-methyl-D-aspartate (NMDA) receptor, p38, and ERK mitogen-activated protein kinase (MAPK) pathway. The blocking of the NMDA receptor by its antagonists MK-801 reduced PGC-1alpha mRNA expression in OGD neurons, while NMDA itself can directly induce the expression of PGC-1alpha in neuronal cells. At the same time, PD98059 (ERK MAPK inhibitor) and SB203580 (P38 MAPK inhibitor) also prevented the up-regulation of PGC-1alpha in OGD neurons and MK801 can inhibit the expression of P38 and ERK MAPK. These data suggested that the expression of PGC-1alpha was up-regulated in OGD mice cortical neurons, which protected the neurons against OGD injury. Moreover, this effect was correlated to the NMDA receptor and the ERK and P38 MAPK pathway. The protective effect of PGC-1alpha on OGD cortical neurons may be useful for stroke therapy.

  8. E-Cigarette Aerosol Exposure Induces Reactive Oxygen Species, DNA Damage, and Cell Death in Vascular Endothelial Cells.

    Anderson, Chastain; Majeste, Andrew; Hanus, Jakub; Wang, Shusheng

    2016-12-01

    Cigarette smoking remains one of the leading causes of preventable death worldwide. Vascular cell death and dysfunction is a central or exacerbating component in the majority of cigarette smoking related pathologies. The recent development of the electronic nicotine delivery systems known as e-cigarettes provides an alternative to conventional cigarette smoking; however, the potential vascular health risks of e-cigarette use remain unclear. This study evaluates the effects of e-cigarette aerosol extract (EAE) and conventional cigarette smoke extract (CSE) on human umbilical vein endothelial cells (HUVECs). A laboratory apparatus was designed to produce extracts from e-cigarettes and conventional cigarettes according to established protocols for cigarette smoking. EAE or conventional CSE was applied to human vascular endothelial cells for 4-72 h, dependent on the assay. Treated cells were assayed for reactive oxygen species, DNA damage, cell viability, and markers of programmed cell death pathways. Additionally, the anti-oxidants α-tocopherol and n-acetyl-l-cysteine were used to attempt to rescue e-cigarette induced cell death. Our results indicate that e-cigarette aerosol is capable of inducing reactive oxygen species, causing DNA damage, and significantly reducing cell viability in a concentration dependent fashion. Immunofluorescent and flow cytometry analysis indicate that both the apoptosis and programmed necrosis pathways are triggered by e-cigarette aerosol treatment. Additionally, anti-oxidant treatment provides a partial rescue of the induced cell death, indicating that reactive oxygen species play a causal role in e-cigarette induced cytotoxicity. © The Author 2016. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  9. Reperfusion does not induce oxidative stress but sustained endoplasmic reticulum stress in livers of rats subjected to traumatic-hemorrhagic shock.

    Duvigneau, Johanna Catharina; Kozlov, Andrey V; Zifko, Clara; Postl, Astrid; Hartl, Romana T; Miller, Ingrid; Gille, Lars; Staniek, Katrin; Moldzio, Rudolf; Gregor, Wolfgang; Haindl, Susanne; Behling, Tricia; Redl, Heinz; Bahrami, Soheyl

    2010-03-01

    Oxidative stress is believed to accompany reperfusion and to mediate dysfunction of the liver after traumatic-hemorrhagic shock (THS). Recently, endoplasmic reticulum (ER) stress has been suggested as an additional factor. This study investigated whether reperfusion after THS leads to increased oxidative and/or ER stress in the liver. In a rat model, including laparotomy, bleeding until decompensation, followed by inadequate or adequate reperfusion phase, three time points were investigated: 40 min, 3 h, and 18 h after shock. The reactive oxygen and nitrogen species and its scavenging capacity (superoxide dismutase 2), the nitrotyrosine formation in proteins, and the lipid peroxidation together with the status of endogenous antioxidants (alpha-tocopherylquinone-alpha-tocopherol ratio) were investigated as markers for oxidative or nitrosylative stress. Mitochondrial function and cytochrome P450 isoform 1A1 activity were analyzed as representatives for hepatocyte function. Activation of the inositol-requiring enzyme 1/X-box binding protein pathway and up-regulation of the 78-kDa glucose-regulated protein were recorded as ER stress markers. Plasma levels of alanine aminotransferase and Bax/Bcl-XL messenger RNA (mRNA) ratio were used as indicators for hepatocyte damage and apoptosis induction. Oxidative or nitrosylative stress markers or representatives of hepatocyte function were unchanged during and short after reperfusion (40 min, 3 h after shock). In contrast, ER stress markers were elevated and paralleled those of hepatocyte damage. Incidence for sustained ER stress and subsequent apoptosis induction were found at 18 h after shock. Thus, THS or reperfusion induces early and persistent ER stress of the liver, independent of oxidative or nitrosylative stress. Although ER stress was not associated with depressed hepatocyte function, it may act as an early trigger of protracted cell death, thereby contributing to delayed organ failure after THS.

  10. Effect of hyperbaric oxygen on lipid peroxidation and visual development in neonatal rats with hypoxia-ischemia brain damage.

    Chen, Jing; Chen, Yan-Hui; Lv, Hong-Yan; Chen, Li-Ting

    2016-07-01

    The aim of the present study was to investigate the effect of hyperbaric oxygen (HBO) on lipid peroxidation and visual development in a neonatal rat model of hypoxic-ischemic brain damage (HIBD). The rat models of HIBD were established by delayed uterus dissection and were divided randomly into two groups (10 rats each): HIBD and HBO-treated HIBD (HIBD+HBO) group. Another 20 rats that underwent sham-surgery were also divided randomly into the HBO-treated and control groups. The rats that underwent HBO treatment received HBO (0.02 MPa, 1 h/day) 24 h after the surgery and this continued for 14 days. When rats were 4 weeks old, their flash visual evoked potentials (F-VEPs) were monitored and the ultrastructures of the hippocampus were observed under transmission electron microscope. The levels of superoxide dismutase (SOD) and malonyldialdehyde (MDA) in the brain tissue homogenate were detected by xanthine oxidase and the thiobarbituric acid colorimetric method. Compared with the control group, the ultrastructures of the pyramidal neurons in the hippocampal CA3 area were distorted, the latencies of F-VEPs were prolonged (P0.05). HBO enhances antioxidant capacity and reduces the ultrastructural damage induced by hypoxic-ischemia, which may improve synaptic reconstruction and alleviate immature brain damage to promote the habilitation of brain function.

  11. Protection against post-irradiation oxygen-dependent damage in barley seeds by catalase and hydrogen peroxide: probable radiation chemistry

    Singh, S.P.; Kesavan, P.C.

    1990-01-01

    Influence of varying concentration of catalase and H 2 O 2 administered individually and in combination treatment during post-hydration on the oxygen-dependent and -independent pathways of damage was assessed in dry barley seeds irradiated in vacuo with 350 Gy of 60 Co gammarays. Both catalase (100 to 500 units/ml) and H 2 O 2 (0.001 to 0.1 mM) afforded significant radioprotection against the post-irradiation O 2 -dependent damage. However, a combination treatment (300 units/ml of catalase and 0.01 mM of H 2 O 2 ) afforded significantl y more protection than either of the additives individually. None of the concentrations of catalase exerted any effect on the O 2 -independent pathway, whereas H 2 O 2 at higher concentrations (1 and 10 mM) significantly potentiated both the O 2 -dependent as well as the -independent components of radiation damage. These observations are better explicable in terms of radiation chemistry. (author). 16 refs., 3 tabs

  12. The influence of oxygen on the induction of radiation damage in DNA in mammalian cells after sensitization by intracellular glutathione depletion

    Schans, G.P. van der; Vos, O.; Roos-Verheij, W.S.D.; Lohman, P.H.M.

    1986-05-01

    Treatment of mammalian cells with buthionine sulphoximine (BSO) or diethyl maleate (DEM) results in a decrease in the intracellular GSH (glutathione) and NPSH (non-protein-bound SH) levels. The effect of depletion of GSH and NPSH on radiosensitivity was studied in relation to the concentration of oxygen during irradiation. Single- and double-strand DNA breaks (ssb and dsb) and cell killing were used as criteria for radiation damage. Under aerobic conditions, BSO and DEM treatment gave a small sensitization of 10-20% for the 3 types of radiation damage. Also under severely hypoxic conditions (0.01 μM oxygen in the medium) the sensitizing effect of both compounds on the induction of ssb and dsb and on cell killing was small (0-30%). At somewhat higher concentrations of oxygen (0.5-10 μM) however, the sensitization amounted to about 90% for the induction of ssb and dsb and about 50% for cell killing. These results strengthen the widely accepted idea that intracellular SH-compounds compete with oxygen and other electron-affinic radiosensitizers with respect to reaction with radiation-induced damage, thus preventing the fixation of DNA damages by oxygen. These results imply that the extent to which SH-compounds affect the radiosensitivity of cells in vivo depends strongly on the local concentration of oxygen. (Auth.)

  13. A role for nuclear translocation of tripeptidyl-peptidase II in reactive oxygen species-dependent DNA damage responses

    Preta, Giulio; Klark, Rainier de [Center for Molecular Medicine (CMM), Department of Medicine, Karolinska Institutet, Karolinska University Hospital, 171 76 Stockholm (Sweden); Glas, Rickard, E-mail: rickard.glas@ki.se [Center for Molecular Medicine (CMM), Department of Medicine, Karolinska Institutet, Karolinska University Hospital, 171 76 Stockholm (Sweden)

    2009-11-27

    Responses to DNA damage are influenced by cellular metabolism through the continuous production of reactive oxygen species (ROS), of which most are by-products of mitochondrial respiration. ROS have a strong influence on signaling pathways during responses to DNA damage, by relatively unclear mechanisms. Previous reports have shown conflicting data on a possible role for tripeptidyl-peptidase II (TPPII), a large cytosolic peptidase, within the DNA damage response. Here we show that TPPII translocated into the nucleus in a p160-ROCK-dependent fashion in response to {gamma}-irradiation, and that nuclear expression of TPPII was present in most {gamma}-irradiated transformed cell lines. We used a panel of nine cell lines of diverse tissue origin, including four lymphoma cell lines (T, B and Hodgkins lymphoma), a melanoma, a sarcoma, a colon and two breast carcinomas, where seven out of nine cell lines showed nuclear TPPII expression after {gamma}-irradiation. Further, this required cellular production of ROS; treatment with either N-acetyl-Cysteine (anti-oxidant) or Rotenone (inhibitor of mitochondrial respiration) inhibited nuclear accumulation of TPPII. The local density of cells was important for nuclear accumulation of TPPII at early time-points following {gamma}-irradiation (at 1-4 h), indicating a bystander effect. Further, we showed that the peptide-based inhibitor Z-Gly-Leu-Ala-OH, but not its analogue Z-Gly-(D)-Leu-Ala-OH, excluded TPPII from the nucleus. This correlated with reduced nuclear expression of p53 as well as caspase-3 and -9 activation in {gamma}-irradiated lymphoma cells. Our data suggest a role for TPPII in ROS-dependent DNA damage responses, through alteration of its localization from the cytosol into the nucleus.

  14. Damaged-self recognition in common bean (Phaseolus vulgaris shows taxonomic specificity and triggers signalling via reactive oxygen species (ROS

    Dalia eDuran

    2014-10-01

    Full Text Available Plants require reliable mechanisms to detect injury. Danger signals or 'damage-associated molecular patterns' (DAMPs are released from stressed host cells and allow injury detection independently of enemy-derived molecules. We studied the response of common bean (Phaseolus vulgaris to the application of leaf homogenate as a source of DAMPs and measured the production of reactive oxygen species (ROS as an early response and the secretion of extrafloral nectar (EFN as a jasmonic acid (JA–dependent late response. We observed a strong taxonomic signal in the response to different leaf homogenates. ROS formation and EFN secretion were highly correlated and responded most strongly to leaf homogenates produced using the same cultivar or closely related accessions, less to a distantly related cultivar of common bean or each of the two congeneric species, P. lunatus and P. coccineus, and not at all to homogenates prepared from species in different genera, not even when using other Fabaceae. Interestingly, leaf homogenates also reduced the infection by the bacterial pathogen, Pseudomonas syringae, when they were applied directly before challenging, although the same homogenates exhibited no direct in vitro inhibitory effect in the bacterium. We conclude that ROS signaling is associated to the induction of EFN secretion and that the specific blend of DAMPs that are released from damaged cells allows the plant to distinguish the 'damaged self' from the damaged 'non-self'. The very early responses of plants to DAMPs can trigger resistance to both, herbivores and pathogens, which should be adaptive because injury facilitates infection, independently of its causal reason.

  15. Cellular and molecular repair of X-ray-induced damage: dependence on oxygen tension and nutritional status

    Spiro, I.J.; Kennedy, K.A.; Stickler, R.; Ling, C.C.

    1985-01-01

    Cellular and molecular repair was studied at 23 0 C using split-dose recovery and alkaline elution techniques, respectively, as a function of cellular oxygen and nutrient conditions. Hypoxic cells in full medium showed a partial reduction in the level of sublethal damage (SLD) repair relative to aerated cells; the respective repair kinetics were similar with a common repair half-time of 30 min. Similarly, hypoxic cells showed a slight reduction in strand break rejoining capacity compared to aerated cells. Under nutrient deprivation, anoxic cells displayed no SLD repair or strand break repair, while aerated cells exhibited the same level of SLD and strand break repair as for well-fed cells. In addition, nutrient deprived cells at low O 2 levels displayed normal SLD and strand break repair capability. These results indicate that both nutrient and O 2 deprivation are necessary for complete inhibition of cellular and molecular repair, and low levels of O 2 can effectively reverse this inhibition

  16. Kallikrein-like amidase activity in renal ischemia and reperfusion

    M.D. Carattino

    2000-05-01

    Full Text Available 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 µg of Evans blue/g dry tissue in the basal condition and 1750 µg 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 DAbs 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

  17. In vitro bacterial cytotoxicity of CNTs: reactive oxygen species mediate cell damage edges over direct physical puncturing.

    Rajavel, Krishnamoorthy; Gomathi, Rajkumar; Manian, Sellamuthu; Rajendra Kumar, Ramasamy Thangavelu

    2014-01-21

    Understanding the bacterial cytotoxicity of CNTs is important for a wide variety of applications in the biomedical, environmental, and health sectors. A majority of the earlier reports attributed the bactericidal cytotoxicity of CNTs to bacterial cell membrane damage by direct physical puncturing. Our results reveal that bacterial cell death via bacterial cell membrane damage is induced by reactive oxygen species (ROS) produced from CNTs and is not due to direct physical puncturing by CNTs. To understand the actual mechanism of bacterial killing, we elucidated the bacterial cytotoxicity of SWCNTs and MWCNTs against Gram-negative human pathogenic bacterial species Escherichia coli, Shigella sonnei, Klebsiella pneumoniae, and Pseudomonas aeruginosa and its amelioration upon functionalizing the CNTs with antioxidant tannic acid (TA). Interestingly, the bacterial cells treated with CNTs exhibited severe cell damage under laboratory (ambient) and sunlight irradiation conditions. However, CNTs showed no cytotoxicity to the bacterial cells when incubated in the dark. The quantitative assessments carried out by us made it explicit that CNTs are effective generators of ROS such as (1)O2, O2(•-), and (•)OH in an aqueous medium under both ambient and sunlight-irradiated conditions. Both naked and TA-functionalized CNTs showed negligible ROS production in the dark. Furthermore, strong correlations were obtained between ROS produced by CNTs and the bacterial cell mortality (with the correlation coefficient varying between 0.7618 and 0.9891) for all four tested pathogens. The absence of bactericidal cytotoxicity in both naked and functionalized CNTs in the dark reveals that the presence of ROS is the major factor responsible for the bactericidal action compared to direct physical puncturing. This understanding of the bactericidal activity of the irradiated CNTs, mediated through the generation of ROS, could be interesting for novel applications such as regulated ROS delivery

  18. Acute reperfusion without recanalization

    Makris, Nikolaos; Chamard, Leila; Mikkelsen, Irene K

    2017-01-01

    Acute reperfusion despite persistent arterial occlusion may occur in up to 30% of ischemic stroke patients. Recruitment of leptomeningeal collaterals may explain this phenomenon. Using dynamic susceptibility-contrast perfusion imaging (DSC-PI), we assessed acute changes in collateral flow among...... patients without recanalization. From a multicenter prospective database (I-KNOW), 46 patients with magnetic resonance angiography visible occlusion in whom both reperfusion and recanalization were assessed within 6 h of onset were identified. Maps of collateral flow at arterial, capillary and late venous...... phases were generated from DSC-PI through inter-frame registration, baseline signal subtraction and temporal summation, and graded blind to all other relevant clinical and radiological data using the Higashida scale. Flow direction and the acute evolution of collaterals were evaluated against...

  19. Altering CO2 during reperfusion of ischemic cardiomyocytes modifies mitochondrial oxidant injury.

    Lavani, Romeen; Chang, Wei-Tien; Anderson, Travis; Shao, Zuo-Hui; Wojcik, Kimberly R; Li, Chang-Qing; Pietrowski, Robert; Beiser, David G; Idris, Ahamed H; Hamann, Kimm J; Becker, Lance B; Vanden Hoek, Terry L

    2007-07-01

    Acute changes in tissue CO2 and pH during reperfusion of the ischemic heart may affect ischemia/reperfusion injury. We tested whether gradual vs. acute decreases in CO2 after cardiomyocyte ischemia affect reperfusion oxidants and injury. Comparative laboratory investigation. Institutional laboratory. Embryonic chick cardiomyocytes. Microscope fields of approximately 500 chick cardiomyocytes were monitored throughout 1 hr of simulated ischemia (PO2 of 3-5 torr, PCO2 of 144 torr, pH 6.8), followed by 3 hrs of reperfusion (PO2 of 149 torr, PCO2 of 36 torr, pH 7.4), and compared with cells reperfused with relative hypercarbia (PCO2 of 71 torr, pH 6.8) or hypocarbia (PCO2 of 7 torr, pH 7.9). The measured outcomes included cell viability (via propidium iodide) and oxidant generation (reactive oxygen species via 2',7'-dichlorofluorescin oxidation and nitric oxide [NO] via 4,5-diaminofluorescein diacetate oxidation). Compared with normocarbic reperfusion, hypercarbia significantly reduced cell death from 54.8% +/- 4.0% to 26.3% +/- 2.8% (p < .001), significantly decreased reperfusion reactive oxygen species (p < .05), and increased NO at a later phase of reperfusion (p < .01). The NO synthase inhibitor N-nitro-L-arginine methyl ester (200 microM) reversed this oxidant attenuation (p < .05), NO increase (p < .05), and the cardioprotection conferred by hypercarbic reperfusion (increasing death to 54.3% +/- 6.0% [p < .05]). Conversely, hypocarbic reperfusion increased cell death to 80.4% +/- 4.5% (p < .01). It also increased reactive oxygen species by almost two-fold (p = .052), without affecting the NO level thereafter. Increased reactive oxygen species was attenuated by the mitochondrial complex III inhibitor stigmatellin (20 nM) when given at reperfusion (p < .05). Cell death also decreased from 85.9% +/- 4.5% to 52.2% +/- 6.5% (p < .01). The nicotinamide adenine dinucleotide phosphate oxidase inhibitor apocynin (300 microM) had no effect on reperfusion reactive oxygen

  20. Inhibition of oxygen-dependent radiation-induced damage by the nitroxide superoxide dismutase mimic, tempol

    Mitchell, J.B.; DeGraff, W.; Kaufman, D.; Krishna, M.C.; Samuni, A.; Finkelstein, E.; Ahn, M.S.; Hahn, S.M.; Gamson, J.; Russo, A.

    1991-01-01

    Stable nitroxide radicals have been previously shown to function as superoxide dismutase (SOD)2 mimics and to protect mammalian cells against superoxide and hydrogen peroxide-mediated oxidative stress. These unique characteristics suggested that nitroxides, such as 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (Tempol), might protect mammalian cells against ionizing radiation. Treating Chinese hamster cells under aerobic conditions with 5, 10, 50, and 100 mM Tempol 10 min prior to X-rays resulted in radiation protection factors of 1.25, 1.30, 2.1, and 2.5, respectively. However, the reduced form of Tempol afforded no protection. Tempol treatment under hypoxic conditions did not provide radioprotection. Aerobic X-ray protection by Tempol could not be attributed to the induction of intracellular hypoxia, increase in intracellular glutathione, or induction of intracellular SOD mRNA. Tempol thus represents a new class of non-thiol-containing radiation protectors, which may be useful in elucidating the mechanism(s) of radiation-induced cellular damage and may have broad applications in protecting against oxidative stress

  1. Oxygen-glucose deprivation preconditioning protects neurons against oxygen-glucose deprivation/reperfusion induced injury via bone morphogenetic protein-7 mediated ERK, p38 and Smad signalling pathways.

    Guan, Junhong; Du, Shaonan; Lv, Tao; Qu, Shengtao; Fu, Qiang; Yuan, Ye

    2016-01-01

    Bone morphogenetic protein (BMP)-7 mediated neuroprotective effect of cerebral ischemic preconditioning (IPC) has been studied in an ischemic animal model, but the underlying cellular mechanisms have not been clearly clarified. In this study, primary cortical neurons and the SH-SY5Y cell line were used to investigate the role of BMP-7 and its downstream signals in the neuroprotective effects of oxygen-glucose deprivation preconditioning (OGDPC). Immunocytochemistry was used to detect the expression of neurofilament in neurons. MTT and lactate dehydrogenase activity assays were used to measure the cytotoxicity. Western blot was used to detect the protein expression of BMP-7 and downstream signals. BMP inhibitor, mitogen-activated protein kinase inhibitors, Smad inhibitor and siRNA of Smad 1 were used to investigate the role of corresponding signalling pathways in the OGDPC. Results showed that OGDPC-induced overexpression of BMP-7 in primary cortical neurons and SH-SY5Y cells. Both of endogenous and exogenous BMP-7 could replicate the neuroprotective effects seen in OGDPC pretreatment. In addition, extracellular regulated protein kinases, p38 and Smad signalling pathway were found to be involved in the neuroprotective effects mediated by OGDPC via BMP-7. This study primarily reveals the cellular mechanisms of the neuroprotection mediated by OGDPC, and provides evidence for better understanding of this intrinsic factor against ischemia. © 2015 Wiley Publishing Asia Pty Ltd.

  2. Effect of a combined treatment with erythropoietin and melatonin on renal ischemia reperfusion injury in male rats.

    Ahmadiasl, Nasser; Banaei, Shokofeh; Alihemati, Alireza; Baradaran, Behzad; Azimian, Ehsan

    2014-12-01

    Renal ischemia reperfusion (IR) is an important cause of renal dysfunction. It contributes to the development of acute renal failure. Oxidative damage from reactive oxygen species is considered to be the principal component involved in the pathophysiological tissue alterations observed during IR. The purpose of this study was to evaluate the effect of a combined treatment with erythropoietin (EPO) plus melatonin (MEL), which are known anti-inflammatory and antioxidant agents, in IR-induced renal injury in rats. Wistar Albino rats were unilaterally nephrectomized and subjected to 45 min of renal pedicle occlusion followed by 24 h of reperfusion. MEL (10 mg/kg, i.p) and EPO (5000 U/kg, i.p) were administered prior to ischemia. After 24 h of reperfusion, blood samples were collected for the determination of superoxide dismutase (SOD), glutathione peroxidase (GPx), plasma levels of total antioxidant capacity (TAC), and malondialdehyde (MDA) and serum urea level. Also, renal samples were taken for histological evaluation. Ischemia reperfusion significantly increased urea, blood SOD, and GPx levels. Histological findings of the IR group indicated that there was increase in tubular and glomerular hyaline cast, thickening of Bowman capsule basement membrane, and renal impairment in the glomerular epithelium. Treatment with EPO and MEL significantly decreased blood SOD, GPx, and urea levels and increased TAC level. In the EPO + MEL group, while the histopathological changes were lower than those in EPO group, they were the same as MEL group. EPO and MEL combination treatment exerted more nephroprotective effects than EPO treatment and nearly had protective effects similar to MEL treatment.

  3. Static inflation attenuates ischemia/reperfusion injury in an isolated rat lung in situ.

    Kao, Shang Jyh; Wang, David; Yeh, Diana Yu-Wung; Hsu, Kang; Hsu, Yung Hsiang; Chen, Hsing I

    2004-08-01

    Ischemia (I)/reperfusion (R) lung injury is an important clinical issue in lung transplantation. In the present study, we observed the effects of lung static inflation, different perfusates, and ventilatory gas with nitrogen or oxygen on the I/R-induced pulmonary damage. A total of 96 male Sprague-Dawley rats were used. The lung was isolated in situ. In an isolated lung, the capillary filtration coefficient (Kfc), lung weight gain (LWG), lung weight (LW)/body weight (BW) ratio, and protein concentration in BAL fluid (PCBAL) were measured or calculated to evaluate the degree of lung injury. Histologic examinations with hematoxylin-eosin staining were performed. I/R caused lung injury, as reflected by increases in Kfc, LWG, LW/BW, and PCBAL. The histopathologic picture revealed the presence of hyaline membrane formation and the infiltration of inflammatory cells. These values were significantly attenuated by static lung inflation. The I/R lung damage appeared to be less in the lung perfused with whole blood than in the lung perfused with an isotonic solution. Therapy with ventilatory air (ie, nitrogen or oxygen) did not alter the I/R lung damage. The data suggest that lung inflation is protective to I/R injury, irrespective of the type of ventilatory air used for treatment. The preservation of the lung for transplantation is better kept at a static inflation state and perfused with whole blood instead of an isotonic physiologic solution.

  4. Production of gamma induced reactive oxygen species and damage of DNA molecule in HaCaT cells under euoxic and hypoxic condition

    Joseph, P.; Bhat, N.N.; Copplestone, D.; Narayana, Y.

    2014-01-01

    The paper deals with the study of gamma radiation induced reactive oxygen species (ROS) generation in normal human keratinocytes (HaCaT) cells and quantification of subsequent damages induced on DNA molecules. The DNA damages induced in cells after gamma irradiation has been analyzed using Alkaline comet assay. The ROS produced in the cells were quantified by measuring fluorescence after loading the cells with 2', 7' dichlorofluorescin diacetate, a dye that is oxidized into a highly fluorescent form in the presence of peroxides. Studies reveal that in HaCaT cells radical generation occurs when exposed to ionizing radiation and it increases with dose. The induced DNA damages also increases with dose and ROS generation. The study clearly shows the importance of ROS in DNA damage induction and the cells possessing elevated levels of DNA damage after radiation exposure is due to the effect of increased levels of intracellular ROS. (author)

  5. Up-regulation of A1M/α1-microglobulin in skin by heme and reactive oxygen species gives protection from oxidative damage.

    Olsson, Magnus G; Allhorn, Maria; Larsson, Jörgen; Cederlund, Martin; Lundqvist, Katarina; Schmidtchen, Artur; Sørensen, Ole E; Mörgelin, Matthias; Akerström, Bo

    2011-01-01

    During bleeding the skin is subjected to oxidative insults from free heme and radicals, generated from extracellular hemoglobin. The lipocalin α(1)-microglobulin (A1M) was recently shown to have reductase properties, reducing heme-proteins and other substrates, and to scavenge heme and radicals. We investigated the expression and localization of A1M in skin and the possible role of A1M in the protection of skin tissue from damage induced by heme and reactive oxygen species. Skin explants, keratinocyte cultures and purified collagen I were exposed to heme, reactive oxygen species, and/or A1M and investigated by biochemical methods and electron microscopy. The results demonstrate that A1M is localized ubiquitously in the dermal and epidermal layers, and that the A1M-gene is expressed in keratinocytes and up-regulated after exposure to heme and reactive oxygen species. A1M inhibited the heme- and reactive oxygen species-induced ultrastructural damage, up-regulation of antioxidation and cell cycle regulatory genes, and protein carbonyl formation in skin and keratinocytes. Finally, A1M bound to purified collagen I (K(d) = 0.96×10(-6) M) and could inhibit and repair the destruction of collagen fibrils by heme and reactive oxygen species. The results suggest that A1M may have a physiological role in protection of skin cells and matrix against oxidative damage following bleeding.

  6. Erdosteine and ebselen as useful agents in intestinal ischemia/reperfusion injury.

    Tunc, Turan; Uysal, Bulent; Atabek, Cuneyt; Kesik, Vural; Caliskan, Bahadir; Oztas, Emin; Ersoz, Nail; Oter, Sukru; Guven, Ahmet

    2009-08-01

    Reactive oxygen and nitrogen species generated during reperfusion of the tissue are characteristic of ischemia/reperfusion (I/R) injury. The purpose of the present study was to investigate whether erdosteine and ebselen, molecules with antioxidant properties and peroxynitrite scavenging capability, respectively, can reduce oxidative stress and histological damage in the rat small bowel subjected to mesenteric I/R injury. Forty Sprague-Dawley rats were divided into five groups equally: sham, I/R, I/R plus erdosteine, I/R plus ebselen, and I/R plus erdosteine and ebselen. Intestinal ischemia for 45 min and reperfusion for 3 d were carried out. Ileal specimens were obtained to determine the tissue levels of malondialdehide (MDA), protein carbonyl content (PCC), superoxide dismutase (SOD), glutathione peroxidase (GPx), nitrite/nitrate (NO(x)) level and histological changes. Intestinal I/R resulted in increased tissue MDA, PCC, and NO(x) levels and decreased SOD and GPx activities. Both erdosteine and ebselen alone significantly decreased MDA, PCC, and NO(x) levels and increased antioxidant enzymes activities, but all values were different from control. These changes almost returned to control values in the group treated with erdostein and ebselen. Histopathologically, the intestinal injury in rats treated with erdosteine and ebselen as well as combination were less than I/R group. Both erdosteine and ebselen were able to attenuate I/R injury of the intestine via inhibition of lipid peroxidation and protein oxidation, maintenance of antioxidant, and free radical scavenger properties. Nevertheless, combination treatment showed more promising results, suggesting that scavenging peroxynitrite nearby antioxidant activity is important in preventing intestinal I/R injury.

  7. Honey improves spermatogenesis and hormone secretion in testicular ischaemia-reperfusion-induced injury in rats.

    Gholami, M; Abbaszadeh, A; Khanipour Khayat, Z; Anbari, K; Baharvand, P; Gharravi, A M

    2018-02-01

    This study was conducted to survey the protective effect of pre-treatment with Persian honey during post-ischaemia reperfusion on ischaemia-reperfusion (IR)-induced testis injury. Animals were divided into four groups of IR, honey + ischaemia- reperfusion (HIR), vitamin C + ischaemia- reperfusion (VIR) and carbohydrates + ischaemia- reperfusion (CIR). The testes were examined for spermatogenesis index. Detection of single- and double-stranded DNA breaks at the early stages of apoptosis was performed. Total serum concentration of FSH, LH and testosterone was measured using ELISA. All data were expressed as mean ± SD in each group, and significance was set at p ≤ .05. Spermatogenesis index was significant in the HIR group (p honey decreases the cellular damage and apoptosis during testicular I/R injury, with significant protective effects on reproductive hormone production. © 2017 Blackwell Verlag GmbH.

  8. Pathophysiology of mesenteric ischemia/reperfusion: a review Fisiopatologia da isquemia e reperfusão mesentérica: revisão

    Nereide Freire Cerqueira

    2005-08-01

    Full Text Available During ischemia, the cell structures are progressively damaged, but restoration of the blood flow, paradoxically, intensifies the lesions caused by the ischemia. The mechanisms of ischemia injury and reperfusion (I/R have not been completely defined and many studies have been realized in an attempt to find an ideal therapy for mesenteric I/R. The occlusion and reperfusion of the splanchnic arteries provokes local and systemic alterations principally derived from the release of cytotoxic substances and the interaction between neutrophils and endothelial cells. Substances involved in the process are discussed in the present review, like oxygen-derived free radicals, nitric oxide, transcription factors, complement system, serotonin and pancreatic proteases. The mechanisms of apoptosis, alterations in other organs, therapeutic and evaluation methods are also discussed.Durante a isquemia, as estruturas celulares são progressivamente lesadas, mas a restauração do fluxo sanguíneo, paradoxalmente, pode agravar o dano celular isquêmico. O mecanismo das lesões de isquemia e reperfusão (I/R ainda não foram completamente definidos e muitos estudos têm sido realizados na tentativa de encontrar uma terapia ideal para I/R mesentérica. A oclusão e a reperfusão das artérias esplâncnicas provocam alteracões locais e sistêmicas derivadas principalmente da liberação de substâncias citotóxicas e da interação entre neutrófilos e células endoteliais. As substâncias envolvidas no processo, como radicais livres derivados do oxigênio, óxido nítrico, fatores de transcrição, sistema complemento, serotonina e proteases pancreáticas, são discutidas na presente revisão. Os mecanismos de apoptose, repercussão sistêmica, terapêutica e métodos de avaliação também são discutidos.

  9. Controlled reperfusion decreased reperfusion induced oxidative stress and evoked inflammatory response in experimental aortic-clamping animal model.

    Jancsó, G; Arató, E; Hardi, P; Nagy, T; Pintér, Ö; Fazekas, G; Gasz, B; Takacs, I; Menyhei, G; Kollar, L; Sínay, L

    2016-09-12

    Revascularization after long term aortic ischaemia in vascular surgery induces reperfusion injury accompanied with oxidative stress and inflammatory responses. The hypothesis of this study was that the aortic occlusion followed by controlled reperfusion (CR) can reduce the ischaemia-reperfusion injury, the systemic and local inflammatory response induced by oxidative stress.Animal model was used. animals underwent a 4-hour infrarenal aortic occlusion followed by continuous reperfusion. Treated group: animals were treated with CR: after a 4-hour infrarenal aortic occlusion we made CR for 30 minutes with the crystalloid reperfusion solution (blood: crystalloid solution ratio 1:1) on pressure 60 Hgmm. Blood samples were collected different times. The developing oxidative stress was detected by the plasma levels of malondialdehyde, reduced glutathion, thiol groups and superoxide dismutase. The inflammatory response was measured by phorbol myristate acetate-induced leukocyte reactive oxygen species production and detection of change in myeloperoxidase levels. The animals were anaesthetized one week after terminating ligation and biopsy was taken from quadriceps muscle and large parenchymal organs.CR significantly reduced the postischaemic oxydative stress and inflammatory responses in early reperfusion period. Pathophysiological results: The rate of affected muscle fibers by degeneration was significantly higher in the untreated animal group. The infiltration of leukocytes in muscle and parenchymal tissues was significantly lower in the treatedgroup.CR can improve outcome after acute lower-limb ischaemia. The results confirm that CR might be also a potential therapeutic approach in vascular surgery against reperfusion injury in acute limb ischaemia. Supported by OTKA K108596.

  10. Reactive oxygen species-mediated DNA damage and apoptosis in human skin epidermal cells after exposure to nickel nanoparticles.

    Alarifi, Saud; Ali, Daoud; Alakhtani, Saad; Al Suhaibani, Entissar S; Al-Qahtani, Ahmed A

    2014-01-01

    Nickel nanoparticles (NiNPs) are increasingly used in various applications due to their unique properties. However, there is little information concerning the toxicity of NiNPs in the human skin cell (A431). The present study was designed to investigate the cytotoxicity, apoptosis, and DNA damage due to NiNPs in A431 cells. A cellular proliferative capacity test showed that NiNPs induce significant cytotoxicity in a dose- and time-dependent manner. NiNPs were also found to induce oxidative stress evidenced by the generation of reactive oxygen species (ROS) and depletion of glutathione (GSH). Further, co-treatment with the antioxidant N-acetylcysteine (NAC) mitigated the ROS generation due to NiNPs, suggesting the potential mechanism of oxidative stress. NiNPs also induced significant elevation of lipid peroxidation, catalase, and superoxide dismutase and caspase-3 activity in A431 cells. In addition, NAC suppressed NiNP-induced caspase-3 activity. DNA fragmentation analysis using the comet assay showed that the NiNPs cause genotoxicity in a dose- and time-dependent manner. Therefore, the study points out the capability of the NiNPs to induce oxidative stress resulting in apoptosis and genotoxicity. This study warrants more careful assessment of NiNPs before their industrial applications.

  11. Uptake and distribution of a labeled fatty acid in a canine model of ischemia with and without reperfusion

    Devous, M.D. Sr.

    1985-01-01

    The relationship between regional myocardial blood flow (RMBF) and the regional distribution of 15-(4-iodophenyl)-9-methyl pentadecanoic acid (9-MPDA) was studied in a canine model of myocardial ischemia with and without reperfusion. Group 1 dogs received 135 min of left anterior descending coronary artery (LAD) occlusion; Group 2 dogs received 90 min of LAD occlusion and 45 min of reflow; and Group 3 dogs received 90 min of LAD occlusion and 3.5 hr of reperfusion. All animals received 9-MPDA 15 min prior to sacrifice, and tracer microspheres prior to occlusion, 5 and 80 min after occlusion, 15 min after reperfusion, and 15 min before the end of reperfusion. In Group 1 (permanent ischemia), 9-MPDA distribution was closely correlated with RMBF both 5 and 80 min after occlusion. In Group 2, 9-MPDA uptake was most closely correlated with reperfusion RMBF rather than ischemic RMBF. However, in 1 animal with good reperfusion, 9-MPDA uptake was reduced and was correlated with ischemic blood flow measured 5 min after occlusion. In Group 3, 9-MPDA uptake was correlated with RMBF measured during the ischemic period and not with reperfusion RMBF. It appears that 9-MPDA uptake is determined by RMBF when flow is limited, or early in reperfusion. With prolonged reperfusion, 9-MPDA uptake is significantly reduced in the ischemic zone in the presence of normal flow. This finding implies that the uptake of this fatty acid during reperfusion is related to myocardial damage (myocardial metabolism?) and not to RMBF

  12. Decreased chronic-stage cortical C-11-flumazenil binding after focal ischemia-reperfusion in baboons - A marker of selective neuronal loss?

    Giffard, C.; Landeau, B.; Kerrouche, N.; Young, A.R.; Giffard, C.; Landeau, B.; Kerrouche, N.; Young, A.R.; Giffard, C.; Landeau, B.; Baron, J.C.

    2008-01-01

    Background and Purpose - Although the penumbra can be saved by early reperfusion, in the rat it is consistently affected by selective neuronal loss. Mapping selective neuronal loss in the living primate would be desirable. Methods - Five young adult baboons underwent 15 O positron emission tomography for cerebral blood flow, cerebral oxygen consumption, and oxygen extraction fraction mapping at baseline and serially during and after 20-hours temporary middle cerebral artery occlusion. At approximately day 30, 11 C-flumazenil (FMZ), a potential positron emission tomography marker of selective neuronal loss, and structural magnetic resonance-based infarct mapping were obtained, and the brain was perfused-fixed. Reduced FMZ binding in non-infarcted cortical middle cerebral artery areas was searched voxel-wise, and specific binding was assessed using compartmental modeling of FMZ time-activity curves. Results - Visual inspection revealed reduced late FMZ uptake in the affected cortical territory, extending well beyond the infarct. Accordingly, the incidence of selected voxels was greater than chance, documenting mildly but significantly reduced FMZ uptake and specific binding. Serial 15 O positron emission tomography revealed moderately severe acute ischemia followed by reperfusion. Histopathology documented only mild neuronal changes in or near the affected areas. Conclusions - We document moderate but definite late FMZ binding decrements in non-infarcted cortical areas in the baboon, consistent with previous rat and human studies. These were acutely characterized by moderate ischemia followed by reperfusion, consistent with neuronal damage from ischemic or reperfusion injury in the salvaged at-risk tissue. Only mild histopathological changes subtended these FMZ alterations suggesting subtle processes such as isolated dendrite or synapse loss. Whether these changes impact on clinical outcome deserves studying because they may be targeted by specific neuro

  13. Neuroprotective effect of hydroxy safflor yellow A against cerebral ischemia-reperfusion injury in rats: putative role of mPTP.

    Ramagiri, Sruthi; Taliyan, Rajeev

    2016-01-01

    Hydroxy safflor yellow A (HSYA) has been translated clinically for cardiovascular diseases. HSYA is also greatly acknowledged for its protective effects against cerebral ischemic-reperfusion (I/R) injury. Although the precise mechanism of cerebral I/R injury is not fully understood, oxygen-derived free radicals and mitochondrial permeability transition pore (mPTP) opening during I/R injury are widely recognized as an important contributor to neuronal injury. Thus, we speculated that the neuroprotective effects of HSYA against cerebral I/R injury may be associated with mPTP modulation. Induction of I/R injury was achieved by 60 min of middle cerebral artery occlusion, followed by reperfusion for 24 h. For behavior and cognitive assessment, neurological scoring (NSS), rotarod, and Y-maze task were performed. Oxidative damage was measured in terms of markers such as malondialdehyde, reduced glutathione, and catalase levels and cerebral infarct volumes were quantified using 2,3,5-triphenyl tetrazolinium chloride staining. I/R injury-induced inflammation was determined using tumor necrosis factor-α (TNF-α) levels. Animals exposed to I/R injury showed neurological severity, functional and cognitive disability, elevated oxidative markers, and TNF-α levels along with large infarct volumes. HSYA treatment during onset of reperfusion ameliorated performance in NSS, rotarod and Y-maze attenuated oxidative damage, TNF-α levels, and infarction rate. However, treatment with carboxyatractyloside, an mPTP opener, 20 min before HSYA, attenuated the protective effect of HSYA. Our study confirmed that protective effect of HSYA may be conferred through its free radical scavenger action followed by inhibiting the opening of mPTP during reperfusion and HSYA might act as a promising therapeutic agent against cerebral I/R injury.

  14. Radiation-induced damage in E. coli B: The effect of superoxide radicals and molecular oxygen. Progress report, December 1, 1978--November 30, 1979

    Samuni, A.; Czapski, G.

    The roles of superoxide radicals and of molecular oxygen in the radiodamage of E. coli B suspended in dilute phosphate buffer were studied. The presence of high concentrations of polyethylene glycol in the γ-irradiated cell suspensions, had no effect on bacterial radiosensitivity. This indicates that the damage was primarily endogenous, i.e. originated intracellularly. Saturation of the cell suspensions with N 2 O doubled the radiosensitivity, thus indicating that OH radicals are responsible for the majority of the damage (indirect radiation effect). The presence of oxygen either in the absence or presence of N 2 O brought about roughly a three-fold increase in the radiosensitivity. Since in the presence of N 2 O all e - /sub aq/ are scavenged by the nitrous oxide rather than by oxygen, this shows that superoxide radicals play no role in the bacterial radiodamage. Our results substantiate the attribution of the oxygen effect to a direct interaction of O 2 with the hydroxyl-radical-damaged sites on vital biomolecules, and exclude any significant contribution of e - /sub aq/ and superoxide radicals to the cellular radiodamage

  15. Reactive oxygen species mediate soft corals-derived sinuleptolide-induced antiproliferation and DNA damage in oral cancer cells

    Chang YT

    2017-07-01

    Full Text Available Yung-Ting Chang,1,2,* Chiung-Yao Huang,3,* Jen-Yang Tang,4,5 Chih-Chuang Liaw,1,3 Ruei-Nian Li,6 Jing-Ru Liu,6 Jyh-Horng Sheu,1,3,7,8 Hsueh-Wei Chang6,9–12 1Doctoral Degree Program in Marine Biotechnology, National Sun Yat-sen University, Kaohsiung, Taiwan; 2Doctoral Degree Program in Marine Biotechnology, Academia Sinica, Taipei, Taiwan; 3Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung, Taiwan; 4Department of Radiation Oncology, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; 5Department of Radiation Oncology, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung, Taiwan; 6Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, Taiwan; 7Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan; 8Frontier Center for Ocean Science and Technology, National Sun Yat-sen University, Kaohsiung, Taiwan; 9Institute of Medical Science and Technology, National Sun Yat-sen University, Kaohsiung, Taiwan; 10Cancer Center, Kaohsiung Medical University Hospital; Kaohsiung Medical University, Kaohsiung, Taiwan; 11Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; 12Research Center for Natural Products and Drug Development, Kaohsiung Medical University, Kaohsiung, Taiwan *These authors contributed equally to this work Abstract: We previously reported that the soft coral-derived bioactive substance, sinuleptolide, can inhibit the proliferation of oral cancer cells in association with oxidative stress. The functional role of oxidative stress in the cell-killing effect of sinuleptolide on oral cancer cells was not investigated as yet. To address this question, we introduced the reactive oxygen species (ROS scavenger (N-acetylcysteine [NAC] in a pretreatment to evaluate the sinuleptolide-induced changes to cell viability, morphology, intracellular

  16. Cordyceps sinensis Oral Liquid Inhibits Damage Induced by Oxygen and Glucose Deprivation in SH-SY5Y Cells.

    Zou, Ying-Xin; Liu, Yu-Xiang; Ruan, Ming-Hua; Zhou, Yi; Wang, Jia-Chun; Chu, Zhi-Yong

    2016-01-01

    Cordyceps sinensis has been used in traditional Chinese medicine for thousands of years. It has been demonstrated to have a variety of biological activities, and an extract of it has been demonstrated to possess a protective effect in occlusion-induced focal cerebral ischemia of the middle cerebral artery in rats. It could be explored as an agent for treatment of ischemic stroke, and the mechanisms need to be studied further. The study intended to investigate the protective effects of the Cordyceps sinensis oral liquid (CSOL) against damage induced by oxygen and glucose deprivation (OGD) in SH-SY5Y cells. DESIGN • The research team designed an in vitro study. The study occurred at the Naval Medical Research Institute in Shanghai, China. SH-SY5Y cells were exposed to CSOL in doses of 0.01, 0.03, 0.10, 0.30, and 1.00 mg/mL, creating 5 intervention groups. The OGD condition was induced by transfer of the cells from high-glucose Dulbecco's Modified Eagle's medium (DMEM) in a box gassed with air containing 5% CO2 to glucose-free DMEM in a box gassed with 94% N2, 5% CO2, and 1% O2. Like the cells for the interventions groups, the cells for a model group were cultured with high-glucose DMEM and were transferred to the OGD, but they received no dose of COSL. Cells in a control group were cultured with high-glucose DMEM, were not transferred to the OGD condition, and did not receive any dose of COSL. Cell viability was assayed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. The apoptosis and the mitochondrial membrane potential (MMP) were detected by flow cytometry, and the protein expression of caspase-3 was observed by western blot. After exposure to OGD, the cell viability of cells treated with 0.01, 0.03, 0.10, 0.30, and 1.00 mg/mL of CSOL increased in a dose-effect relationship. Compared with the cells in the model group, the treatment of CSOL at all the experimental concentrations significantly inhibited both the cell apoptosis

  17. ETV6/RUNX1 Induces Reactive Oxygen Species and Drives the Accumulation of DNA Damage in B Cells

    Hans-Peter Kantner

    2013-11-01

    Full Text Available The t(12;21(p13;q22 chromosomal translocation is the most frequent translocation in childhood B cell precursor-acute lymphoblastic leukemia and results in the expression of an ETV6/RUNX1 fusion protein. The frequency of ETV6/RUNX1 fusions in newborns clearly exceeds the leukemia rate revealing that additional events occur in ETV6/RUNX1-positive cells for leukemic transformation. Hitherto, the mechanisms triggering these second hits remain largely elusive. Thus, we generated a novel ETV6/RUNX1 transgenic mouse model where the expression of the fusion protein is restricted to CD19+ B cells. These animals harbor regular B cell development and lack gross abnormalities. We established stable pro-B cell lines carrying the ETV6/RUNX1 transgene that allowed us to investigate whether ETV6/RUNX1 itself favors the acquisition of second hits. Remarkably, these pro-B cell lines as well as primary bone marrow cells derived from ETV6/RUNX1 transgenic animals display elevated levels of reactive oxygen species (ROS as tested with ETV6/RUNX1 transgenic dihydroethidium staining. In line, intracellular phospho-histone H2AX flow cytometry and comet assay revealed increased DNA damage indicating that ETV6/RUNX1 expression enhances ROS. On the basis of our data, we propose the following model: the expression of ETV6/RUNX1 creates a preleukemic clone and leads to increased ROS levels. These elevated ROS favor the accumulation of secondary hits by increasing genetic instability and doublestrand breaks, thus allowing preleukemic clones to develop into fully transformed leukemic cells.

  18. Anti-inflammatory and antioxidant effects of flavonoid-rich fraction of bergamot juice (BJe in a mouse model of intestinal ischemia/reperfusion injury

    Daniela Impellizzeri

    2016-07-01

    Full Text Available The flavonoid-rich fraction of bergamot juice (BJe has demonstrated anti-inflammatory and antioxidant activities. The aim of work was to test the beneficial effects of BJe on the modulation of the ileum inflammation caused by intestinal ischemia/reperfusion (I/R injury in mice. To understand the cellular mechanisms by which BJe may decrease the development of intestinal I/R injury, we have evaluated the activation of signaling transduction pathways that can be induced by reactive oxygen species (ROS production. Superior mesenteric artery and celiac trunk were occluded for 30 min and reperfused for 1 h. The animals were sacrificed after 1 h of reperfusion, for both histological and molecular examinations of the ileum tissue. The experimental results demonstrated that BJe was able to reduce histological damage, cytokines production, adhesion molecules expression, neutrophil infiltration and oxidative stress by a mechanism involved both NF-κB and MAP kinases pathways. This study indicates that BJe could represent a new treatment against inflammatory events of intestinal I/R injury.

  19. Hypoxia inducible factor 1-alpha (HIF-1 alpha is induced during reperfusion after renal ischemia and is critical for proximal tubule cell survival.

    Elisa Conde

    Full Text Available Acute tubular necrosis (ATN caused by ischemia/reperfusion (I/R during renal transplantation delays allograft function. Identification of factors that mediate protection and/or epithelium recovery could help to improve graft outcome. We studied the expression, regulation and role of hypoxia inducible factor 1-alpha (HIF-1 α, using in vitro and in vivo experimental models of I/R as well as human post-transplant renal biopsies. We found that HIF-1 α is stabilized in proximal tubule cells during ischemia and unexpectedly in late reperfusion, when oxygen tension is normal. Both inductions lead to gene expression in vitro and in vivo. In vitro interference of HIF-1 α promoted cell death and in vivo interference exacerbated tissue damage and renal dysfunction. In pos-transplant human biopsies, HIF-1 α was expressed only in proximal tubules which exhibited normal renal structure with a significant negative correlation with ATN grade. In summary, using experimental models and human biopsies, we identified a novel HIF-1 α induction during reperfusion with a potential critical role in renal transplant.

  20. Radiation-induced damage in T4 bacteriophage: the effect of superoxid radicals and molecular oxygen. Progress report, December 1, 1977--November 30, 1978

    Samuni, A.; Chevion, M.; Halpern, Y.S.; Ilan, Y.A.; Czapski, G.

    1978-01-01

    The sensitivity of T4 bacteriophage towards γ irradiation has been studied in phosphate buffer suspensions. The spectrum of the water radicals was controlled by a careful choice of the appropriate saturating gas and the addition of radical scavengers. Thus, it was possible to distinguish between the effects of molecular oxygen and the superoxide radicals formed through its reactions. About 90 percent of the damage was caused by the water radicals formed in the bulk suspensions. These probably affected the phage proteins; only the remainder of the damage involved the viral DNA. The oxygen enhancement ratio observed was not connected in any way with the formation of the superoxide radicals. The results confirmed that the OH radicals are the reactive species, while e - /sub aq/ as well as the superoxide radical do not contribute to the radiodamage

  1. Drugs for stroke: action of nitrone (Z)-N-(2-bromo-5-hydroxy-4-methoxybenzylidene)-2-methylpropan-2-amine oxide on rat cortical neurons in culture subjected to oxygen-glucose-deprivation.

    Arce, Carmen; Diaz-Castroverde, Sabela; Canales, María J; Marco-Contelles, José; Samadi, Abdelouahid; Oset-Gasque, María J; González, María P

    2012-09-01

    The action of (Z)-N-(2-bromo-5-hydroxy-4-methoxybenzylidene)-2-methylpropan-2-amine oxide (RP6) on rat cortical neurons in culture, under oxygen-glucose-deprivation conditions, is reported. Cortical neurons in culture were treated during 1 h with OGD. After, they were placed under normal conditions during 24 h (reperfusion) in absence and presence of RP6. Different parameters were measured under each condition (control, 1 h OGD and 1 h OGD + reperfusion in absence and presence of RP6). RP6 protects neurons against ROS generation, lipid peroxidation levels, LDH release and mitochondrial membrane potential alteration, when administered during reperfusion after the OGD damage. Consequently, these results show that nitrone RP6 protects cells against ischemia injury produced during the reoxygenation, and could be a potential drug for the ictus therapy. Copyright © 2012. Published by Elsevier Masson SAS.

  2. Effects of defibrotide, a novel oligodeoxyribonucleotide, on ischaemia and reperfusion injury of the rat liver.

    Kim, Kwang Joon; Shin, Yong Kyoo; Song, Jin Ho; Oh, Byung Kwon; Choi, Myung Sup; Sohn, Uy Dong

    2002-02-01

    1. The purpose of this study was to investigate the protective effects of defibrotide, a single-stranded polydeoxyribonucleotide, on ischaemia-reperfusion injury to the liver using a rat model. 2. Ischaemia of the left and median lobes was created by total inflow occlusion for 30 min followed by 60 min of reperfusion. Hepatic injury was assessed by the release of liver enzymes (alanine transferase, ALT and lactic dehydrogenase, LDH). Hepatic oxidant stress was measured by superoxide production, lipid peroxidation and nitrite/nitrate formation. Leukocyte-endothelium interaction and Kupffer cell mobilization were quantified by measuring hepatic myeloperoxidase (MPO), polymorphonuclear leukocyte adherence to superior mesenteric artery (SMA) and immunostaining of Kupffer cell. 3. Defibrotide treatment resulted in a significant inhibition of postreperfusion superoxide generation, lipid peroxidation, serum ALT activity, serum LDH activity, MPO activity, serum nitrite/nitrate level, leukocyte adherence to SMA, and Kupffer cell mobilization, indicating a significant attenuation of hepatic dysfunction. 4. A significant correlation existed between liver ischaemia/reperfusion and hepatic injury, suggesting that liver ischaemia/reperfusion injury is mediated predominantly by generation of oxygen free radicals and mobilization of Kupffer cells. 5. We conclude that defibrotide significantly protects the liver against liver ischaemia/reperfusion injury by interfering with Kupffer cell mobilization and formation of oxygen free radicals. This study provides strong evidence that defibrotide has important beneficial effects on acute inflammatory tissue injury such as that occurring in the reperfusion of the ischaemic liver.

  3. Hearts from mice fed a non-obesogenic high-fat diet exhibit changes in their oxidative state, calcium and mitochondria in parallel with increased susceptibility to reperfusion injury.

    Littlejohns, Ben; Pasdois, Philippe; Duggan, Simon; Bond, Andrew R; Heesom, Kate; Jackson, Christopher L; Angelini, Gianni D; Halestrap, Andrew P; Suleiman, M-Saadeh

    2014-01-01

    High-fat diet with obesity-associated co-morbidities triggers cardiac remodeling and renders the heart more vulnerable to ischemia/reperfusion injury. However, the effect of high-fat diet without obesity and associated co-morbidities is presently unknown. To characterize a non-obese mouse model of high-fat diet, assess the vulnerability of hearts to reperfusion injury and to investigate cardiac cellular remodeling in relation to the mechanism(s) underlying reperfusion injury. Feeding C57BL/6J male mice high-fat diet for 20 weeks did not induce obesity, diabetes, cardiac hypertrophy, cardiac dysfunction, atherosclerosis or cardiac apoptosis. However, isolated perfused hearts from mice fed high-fat diet were more vulnerable to reperfusion injury than those from mice fed normal diet. In isolated cardiomyocytes, high-fat diet was associated with higher diastolic intracellular Ca2+ concentration and greater damage to isolated cardiomyocytes following simulated ischemia/reperfusion. High-fat diet was also associated with changes in mitochondrial morphology and expression of some related proteins but not mitochondrial respiration or reactive oxygen species turnover rates. Proteomics, western blot and high-performance liquid chromatography techniques revealed that high-fat diet led to less cardiac oxidative stress, higher catalase expression and significant changes in expression of putative components of the mitochondrial permeability transition pore (mPTP). Inhibition of the mPTP conferred relatively more cardio-protection in the high-fat fed mice compared to normal diet. This study shows for the first time that high-fat diet, independent of obesity-induced co-morbidities, triggers changes in cardiac oxidative state, calcium handling and mitochondria which are likely to be responsible for increased vulnerability to cardiac insults.

  4. The pathways by which mild hypothermia inhibits neuronal apoptosis following ischemia/reperfusion injury

    Chun Luo

    2015-01-01

    Full Text Available Several studies have demonstrated that mild hypothermia exhibits a neuroprotective role and it can inhibit endothelial cell apoptosis following ischemia/reperfusion injury by decreasing casp-ase-3 expression. It is hypothesized that mild hypothermia exhibits neuroprotective effects on neurons exposed to ischemia/reperfusion condition produced by oxygen-glucose deprivation. Mild hypothermia significantly reduced the number of apoptotic neurons, decreased the expression of pro-apoptotic protein Bax and increased mitochondrial membrane potential, with the peak of anti-apoptotic effect appearing between 6 and 12 hours after the injury. These findings indicate that mild hypothermia inhibits neuronal apoptosis following ischemia/reperfusion injury by protecting the mitochondria and that the effective time window is 6-12 hours after ischemia/reperfusion injury

  5. Enhancement of chemically induced reactive oxygen species production and DNA damage in human SH-SY5Y neuroblastoma cells by 872 MHz radiofrequency radiation

    Luukkonen, Jukka [Department of Environmental Science, University of Kuopio, Bioteknia 2, P.O. Box 1627, FI-70211 Kuopio (Finland)], E-mail: Jukka.Luukkonen@uku.fi; Hakulinen, Pasi; Maeki-Paakkanen, Jorma [Department of Environmental Health, National Public Health Institute, P.O. Box 95, FI-70701 Kuopio (Finland); Juutilainen, Jukka; Naarala, Jonne [Department of Environmental Science, University of Kuopio, Bioteknia 2, P.O. Box 1627, FI-70211 Kuopio (Finland)

    2009-03-09

    The objective of the study was to investigate effects of 872 MHz radiofrequency (RF) radiation on intracellular reactive oxygen species (ROS) production and DNA damage at a relatively high SAR value (5 W/kg). The experiments also involved combined exposure to RF radiation and menadione, a chemical inducing intracellular ROS production and DNA damage. The production of ROS was measured using the fluorescent probe dichlorofluorescein and DNA damage was evaluated by the Comet assay. Human SH-SY5Y neuroblastoma cells were exposed to RF radiation for 1 h with or without menadione. Control cultures were sham exposed. Both continuous waves (CW) and a pulsed signal similar to that used in global system for mobile communications (GSM) mobile phones were used. Exposure to the CW RF radiation increased DNA breakage (p < 0.01) in comparison to the cells exposed only to menadione. Comparison of the same groups also showed that ROS level was higher in cells exposed to CW RF radiation at 30 and 60 min after the end of exposure (p < 0.05 and p < 0.01, respectively). No effects of the GSM signal were seen on either ROS production or DNA damage. The results of the present study suggest that 872 MHz CW RF radiation at 5 W/kg might enhance chemically induced ROS production and thus cause secondary DNA damage. However, there is no known mechanism that would explain such effects from CW RF radiation but not from GSM modulated RF radiation at identical SAR.

  6. Enhancement of chemically induced reactive oxygen species production and DNA damage in human SH-SY5Y neuroblastoma cells by 872 MHz radiofrequency radiation

    Luukkonen, Jukka; Hakulinen, Pasi; Maeki-Paakkanen, Jorma; Juutilainen, Jukka; Naarala, Jonne

    2009-01-01

    The objective of the study was to investigate effects of 872 MHz radiofrequency (RF) radiation on intracellular reactive oxygen species (ROS) production and DNA damage at a relatively high SAR value (5 W/kg). The experiments also involved combined exposure to RF radiation and menadione, a chemical inducing intracellular ROS production and DNA damage. The production of ROS was measured using the fluorescent probe dichlorofluorescein and DNA damage was evaluated by the Comet assay. Human SH-SY5Y neuroblastoma cells were exposed to RF radiation for 1 h with or without menadione. Control cultures were sham exposed. Both continuous waves (CW) and a pulsed signal similar to that used in global system for mobile communications (GSM) mobile phones were used. Exposure to the CW RF radiation increased DNA breakage (p < 0.01) in comparison to the cells exposed only to menadione. Comparison of the same groups also showed that ROS level was higher in cells exposed to CW RF radiation at 30 and 60 min after the end of exposure (p < 0.05 and p < 0.01, respectively). No effects of the GSM signal were seen on either ROS production or DNA damage. The results of the present study suggest that 872 MHz CW RF radiation at 5 W/kg might enhance chemically induced ROS production and thus cause secondary DNA damage. However, there is no known mechanism that would explain such effects from CW RF radiation but not from GSM modulated RF radiation at identical SAR

  7. Isoflurane produces sustained cardiac protection after ischemia-reperfusion injury in mice.

    Tsutsumi, Yasuo M; Patel, Hemal H; Lai, N Chin; Takahashi, Toshiyuki; Head, Brian P; Roth, David M

    2006-03-01

    Isoflurane reduces myocardial ischemia-reperfusion injury within hours to days of reperfusion. Whether isoflurane produces sustained cardiac protection has never been examined. The authors studied isoflurane-induced cardiac protection in the intact mouse after 2 h and 2 weeks of reperfusion and determined the dependence of this protection on adenosine triphosphate-dependent potassium channels and the relevance of this protection to myocardial function and apoptosis. Mice were randomly assigned to receive oxygen or isoflurane for 30 min with 15 min of washout. Some mice received mitochondrial (5-hydroxydecanoic acid) or sarcolemmal (HMR-1098) adenosine triphosphate-dependent potassium channel blockers with or without isoflurane. Mice were then subjected to a 30-min coronary artery occlusion followed by 2 h or 2 weeks of reperfusion. Infarct size was determined at 2 h and 2 weeks of reperfusion. Cardiac function and apoptosis were determined 2 weeks after reperfusion. Isoflurane did not change hemodynamics. Isoflurane reduced infarct size after reperfusion when compared with the control groups (27.7 +/- 6.3 vs. 41.7 +/- 6.4% at 2 h and 19.6 +/- 5.9 vs. 28.8 +/- 9.0% at 2 weeks). Previous administration of 5-hydroxydecanoic acid, but not HMR-1098, abolished isoflurane-induced cardiac protection. At 2 weeks, left ventricular end-diastolic diameter was decreased significantly and end-systolic pressure and maximum and minimum dP/dt were improved by isoflurane. Isoflurane-treated mice subjected to ischemia and 2 weeks of reperfusion showed less expression of proapoptotic genes, significantly decreased expression of cleaved caspase-3, and significantly decreased deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling-positive nuclei compared with the control group. Cardiac protection induced by isoflurane against necrotic and apoptotic cell death is associated with an acute memory period that is sustained and functionally relevant 2 weeks after

  8. Targeting reactive nitrogen species: a promising therapeutic strategy for cerebral ischemia-reperfusion injury.

    Chen, Xing-miao; Chen, Han-sen; Xu, Ming-jing; Shen, Jian-gang

    2013-01-01

    Ischemic stroke accounts for nearly 80% of stroke cases. Recanalization with thrombolysis is a currently crucial therapeutic strategy for re-building blood supply, but the thrombolytic therapy often companies with cerebral ischemia-reperfusion injury, which are mediated by free radicals. As an important component of free radicals, reactive nitrogen species (RNS), including nitric oxide (NO) and peroxynitrite (ONOO(-)), play important roles in the process of cerebral ischemia-reperfusion injury. Ischemia-reperfusion results in the production of nitric oxide (NO) and peroxynitrite (ONOO(-)) in ischemic brain, which trigger numerous molecular cascades and lead to disruption of the blood brain barrier and exacerbate brain damage. There are few therapeutic strategies available for saving ischemic brains and preventing the subsequent brain damage. Recent evidence suggests that RNS could be a therapeutic target for the treatment of cerebral ischemia-reperfusion injury. Herein, we reviewed the recent progress regarding the roles of RNS in the process of cerebral ischemic-reperfusion injury and discussed the potentials of drug development that target NO and ONOO(-) to treat ischemic stroke. We conclude that modulation for RNS level could be an important therapeutic strategy for preventing cerebral ischemia-reperfusion injury.

  9. On the mechanism of differential modification of oxygen dependent and independent radiation damage in Hordeum vulgare by caffeine

    Sah, N.K.; Kesavan, P.C.

    1986-01-01

    Barley seeds (IB65) of 4 per cent moisture content were irradiated in vacuo with 350 Gy gamma radiation and post-treated with or without caffeine under oxygenated and oxygen-free conditions. 8-day old seedling height was measured, chromosomal aberrations in 48 hr old shoot-tips were scored and DNA synthesis was assayed by tritiated thymidine incorporation studies at 12, 24 and 36 hr after hydration (these hrs coincide with the first three S-phases). Caffeine has been found to reduce the level of radiation-induced seedling injury and chromosomal aberration and to enhance the magnitude of DNA synthesis under oxygenated condition. The level of seedling injury and chromosomal aberration and the magnitude of DNA synthesis are, however, enhanced under oxygen-free condition by caffeine. (author)

  10. DNA Damage: Quantum Mechanics/Molecular Mechanics Study on the Oxygen Binding and Substrate Hydroxylation Step in AlkB Repair Enzymes

    Quesne, Matthew G; Latifi, Reza; Gonzalez-Ovalle, Luis E; Kumar, Devesh; de Visser, Sam P

    2014-01-01

    AlkB repair enzymes are important nonheme iron enzymes that catalyse the demethylation of alkylated DNA bases in humans, which is a vital reaction in the body that heals externally damaged DNA bases. Its mechanism is currently controversial and in order to resolve the catalytic mechanism of these enzymes, a quantum mechanics/molecular mechanics (QM/MM) study was performed on the demethylation of the N1-methyladenine fragment by AlkB repair enzymes. Firstly, the initial modelling identified the oxygen binding site of the enzyme. Secondly, the oxygen activation mechanism was investigated and a novel pathway was found, whereby the catalytically active iron(IV)–oxo intermediate in the catalytic cycle undergoes an initial isomerisation assisted by an Arg residue in the substrate binding pocket, which then brings the oxo group in close contact with the methyl group of the alkylated DNA base. This enables a subsequent rate-determining hydrogen-atom abstraction on competitive σ-and π-pathways on a quintet spin-state surface. These findings give evidence of different locations of the oxygen and substrate binding channels in the enzyme and the origin of the separation of the oxygen-bound intermediates in the catalytic cycle from substrate. Our studies are compared with small model complexes and the effect of protein and environment on the kinetics and mechanism is explained. PMID:24339041

  11. Dependence of diameters and oxygen saturation of retinal vessels on visual field damage and age in primary open-angle glaucoma.

    Ramm, Lisa; Jentsch, Susanne; Peters, Sven; Sauer, Lydia; Augsten, Regine; Hammer, Martin

    2016-05-01

    To investigate the interrelationship between the oxygen supply of the retina and its regulation with the severity of primary open-angle glaucoma (POAG). Central retinal artery (CRAE) and vein (CRVE) diameters and oxygen saturation of peripapillary retinal vessels in 41 patients suffering from POAG (64.1 ± 12.9 years) and 40 healthy volunteers (63.6 ± 14.1 years) were measured using the retinal vessel analyzer. All measures were taken before and during flicker light stimulation. The mean retinal nerve fiber layer thickness (RNFLT) was determined by OCT and the visual field mean defect (MD) was identified using perimetry. In glaucoma patients, CRAE (r = -0.48 p = 0.002) and CRVE (r = -0.394 p = 0.014) at baseline were inversely related to MD, while arterial and venous oxygen saturation showed no significant dependence on the severity of the damage. However, the flicker light-induced change in arterio-venous difference in oxygen saturation was correlated with the MD (r = 0.358 p = 0.027). The diameters of arteries and veins at baseline decreased with reduction of the mean RNFLT (arteries: r = 0.718 p field loss, may be explained by a reduction of the retinal metabolic demand with progressive loss of neuronal tissue in glaucoma. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  12. Extraction of water labeled with oxygen 15 during single-capillary transit. Influence of blood pressure, osmolarity, and blood-brain barrier damage

    Go, K.G.; Lammertsma, A.A.; Paans, A.M.; Vaalburg, W.; Woldring, M.G.

    1981-01-01

    By external detection, the influence of arterial blood pressure (BP), osmolarity, and cold-induced blood-brain barrier damage was assessed on the extraction of water labeled with oxygen 15 during single-capillary transit in the rat. There was an inverse relation between arterial BP and extraction that was attributable to the influence of arterial BP on cerebral blood flow (CBF) and the relation between CBF and extraction. Neither arterial BP nor osmolarity of the injected bolus had any direct effect on extraction of water 15O, signifying that the diffusional exchange component (determined by blood flow) of extraction greatly surpasses the convection flow contribution by hydrostatic or osmotic forces. Damage to the blood-brain barrier did not change its permeability to water

  13. Electrolysed reduced water decreases reactive oxygen species-induced oxidative damage to skeletal muscle and improves performance in broiler chickens exposed to medium-term chronic heat stress.

    Azad, M A K; Kikusato, M; Zulkifli, I; Toyomizu, M

    2013-01-01

    1. The present study was designed to achieve a reduction of reactive oxygen species (ROS)-induced oxidative damage to skeletal muscle and to improve the performance of broiler chickens exposed to chronic heat stress. 2. Chickens were given a control diet with normal drinking water, or diets supplemented with cashew nut shell liquid (CNSL) or grape seed extract (GSE), or a control diet with electrolysed reduced water (ERW) for 19 d after hatch. Thereafter, chickens were exposed to a temperature of either 34°C continuously for a period of 5 d, or maintained at 24°C, on the same diets. 3. The control broilers exposed to 34°C showed decreased weight gain and feed consumption and slightly increased ROS production and malondialdehyde (MDA) concentrations in skeletal muscle. The chickens exposed to 34°C and supplemented with ERW showed significantly improved growth performance and lower ROS production and MDA contents in tissues than control broilers exposed to 34°C. Following heat exposure, CNSL chickens performed better with respect to weight gain and feed consumption, but still showed elevated ROS production and skeletal muscle oxidative damage. GSE chickens did not exhibit improved performance or reduced skeletal muscle oxidative damage. 4. In conclusion, this study suggests that ERW could partially inhibit ROS-induced oxidative damage to skeletal muscle and improve growth performance in broiler chickens under medium-term chronic heat treatment.

  14. Biological and Histopathological Investigations of Moclobemide on Injured Ovarian Tissue Following Induction of Ischemia-Reperfusion in Rats

    Metin Ingec

    2012-01-01

    Full Text Available Background: The effects of moclobemide on damaged ovarian tissue induced by ischemia-reperfusion and damaged contralateral ovarian tissue were investigated in rats,biochemically and histologically.Materials and Methods: In this experimental study, 40 rats were equally divided intofour groups: 10 mg/kg moclobemide, 20 mg/kg moclobemide, ischemia/reperfusion control,and intact control groups. A 2-2.5-cm-long vertical incision was made in the lowerabdomen of each rat in order to reach the ovaries, after which a vascular clip was placedon the lower side of the right ovary of each animal in the two treatment groups and theischemia-reperfusion control group, but not in the healthy (intact control animal group.The purpose of this procedure was to create ischemia over the course of three hours, thenthe clips were unclamped to provide reperfusion for the next two hours. At the end ofthe two hours of reperfusion, all the animals were killed by high-dose anaesthesia andtheir ovaries were taken and subjected to histological and biochemical (malondialdehyde,nitric oxide, glutathione studies.Results: The obtained results showed that moclobemide suppressed nitric oxide andmalondialdehyde production in the ischemia - reperfusion damage area, and preventedthe decrease in endogenous antioxidant levels (glutathione in the rat ovariantissue. Moclobemide also prevented infiltration of leukocytes to the ovarian tissue.These results showed that moclobemide protected ovarian tissue against ischemiareperfusioninjury.Conclusion: This study shows that moclobemide represses malondialdehyde and nitricoxide production in the rat ovarian tissue subjected to ischemia-reperfusion injury andkeeps the endogenous antioxidant glutathione level from decreasing. Moclobemide alsoinhibits leukocytic migration into ovarian tissue following ischemia-reperfusion injury.From these results, it is suggested that moclobemide can be used in the treatment of ovarianischemia-reperfusion injury.

  15. Effects of iron salts and haemosiderin from a thalassaemia patient on oxygen radical damage as measured in the comet assay

    Anderson, D.; Yardley-Jones, A.; Hambly, R.J.; Vives-Bauza, C.; Smykatz-Kloss, V.; Chua-anusorn, W.; Webb, J.

    2000-01-01

    Thalassaemia is a group of genetic diseases where haemoglobin synthesis is impaired. This chronic anaemia leads to increased dietary iron absorption, which develops into iron overload pathology. Treatment through regular transfusions increases oxygen capacity but also provides iron through the red

  16. Lower limb ischaemia and reperfusion injury in healthy volunteers measured by oxidative and inflammatory biomarkers

    Halladin, N. L.; Busch, Sarah Victoria Ekeløf; Alamili, M.

    2015-01-01

    OBJECTIVE: Ischaemia-reperfusion (IR) injury is partly caused by the release of reactive oxygen species and cytokines and may result in remote organ injury. Surgical patients are exposed to surgical stress and anaesthesia, both of which can influence the IR response. An IR model without these int......OBJECTIVE: Ischaemia-reperfusion (IR) injury is partly caused by the release of reactive oxygen species and cytokines and may result in remote organ injury. Surgical patients are exposed to surgical stress and anaesthesia, both of which can influence the IR response. An IR model without...... at any sampling time. CONCLUSION: Twenty minutes of lower limb ischaemia does not result in an ischaemia-reperfusion injury in healthy volunteers, measurable by oxidative and pro- and anti-inflammatory biomarkers in muscle biopsies and in the systemic circulation....

  17. Induction of intestinal ischemia reperfusion injury by portal vein outflow occlusion in rats

    Vincenti, M.; Behrends, M.; Hirose, Ryutaro; Liu, T.; Niemann, C.U.; Dang, K.; Park, Y.H.; Blasi-Ibanez, A.; Serkova, N.J.

    2010-01-01

    Intestinal ischemia can occur from mesenteric artery (MA) occlusion and portal vein (PV) occlusion. The degree and mechanisms of ischemia/reperfusion (I/R) injury in these conditions may differ. Metabolic changes are seen early in I/R. This study compares tissue histology, inflammation, and metabolic response during small bowel I/R due to superior MA or PV occlusion. Anesthetized male Wistar rats (250-300 g) underwent laparotomy followed by MA or PV occlusion for 40 min. After 120 min of reperfusion, small bowel tissue was collected. The expression of heat shock protein (HSP)-32 and HSP70 was evaluated to compare physiological stress responses between groups. Metabolic profiles were obtained using 1 H-nuclear magnetic resonance spectroscopy (NMR)-based quantitative metabolomics. Histological injury of small bowel was graded from 0 (normal) to 4 (extensive ischemic damage). Protein expression of HSP32 and HSP70 increased when compared to sham but was not different in the MA I/R and PV I/R groups. Metabolic profiles demonstrated decreased glucose levels and highly elevated tissue lactate and amino acids and fatty acids following I/R, with more pronounced changes with PV occlusion. Lipid peroxidation was equally increased in both groups, while depletion of reduced glutathione (GSH) was more severe with MA occlusion. The epithelial necrosis score was higher with MA (3.5±0.6) than with PV occlusion (2.3±0.8). Histological injury of the intestine is less pronounced following PV occlusion, most likely due to higher oxygen and substrate availability during I/R by PV occlusion. This conclusion is supported by a more pronounced metabolic synthetic response (increased glycolysis and fatty acid and amino acid accumulation) with PV occlusion, while oxidative stress was higher with MA occlusion. The inflammatory response showed little difference between the groups. (author)

  18. Mitofusin 2 Exerts a Protective Role in Ischemia Reperfusion Injury Through Increasing Autophagy

    Cheng Peng

    2018-05-01

    Full Text Available Background/Aims: Autophagy is essential for maintaining cellular homeostasis and the survival of terminally differentiated cells as neurons. In this study, we aim to investigate whether mitofusin 2, a mitochondrial fusion protein, mediates autophagy in cerebral ischemia/reperfusion (I/R injury. Methods: Primary cultured neurons were treated with oxygen-glucose deprivation/reperfusion to mimic cerebral I/R injury in vitro. Autophagosomes were visualized upon TEM. Autophagy-markers were then detected to monitor autophagy by western-blot and real-time PCR, and the autophagic flux was tracked with a mRFP-GFP-LC3 construct by fluorescence as well as autophagy inhibitors and agonists. The up- and downregulation of Mfn2 were through transfecting a lentivirusexpression vector respectively. And neuronal injury was detected by cell counting kit and TUNEL assay. Results: Results showed I/R increased autophagosome formation and inhibited autolysosome degradation. Furthermore, use of autophagy related agents demonstrated that I/R injury was caused by insufficient autophagy and aggravated by impaired autophagic degradation. The results also indicated that mitofusin 2 could ameliorate I/R injury through increasing autophagosome formation and promoting the fusion of autophagosomes and lysosomes. In contrast, downregulation of mitofusin 2 aggravated the I/R injury by inhibiting autophagosome formation and the fusion of autophagosomes and lysosomes. Additionly, mitofusin 2 overexpression did not lead to autolysosome accumulation induced by I/R. Conclusions: In summary, this study explicitly demonstrated that mitofusin 2 could ameliorate I/R injury mainly through promoting autophagy, which represented a potential novel strategy for neuroprotection against cerebral I/R damage.

  19. Spectroscopic photoacoustics for assessing ischemic kidney damage

    Berndl, Elizabeth S. L.; He, Xiaolin; Yuen, Darren A.; Kolios, Michael C.

    2018-02-01

    Ischemic reperfusion injuries (IRIs) are caused by return of blood to a tissue or organ after a period without oxygen or nutrients. Damage in the microvasculature causes an inflammatory response and heterogeneous scarring, which is associated with an increase in collagen in the extracellular matrix. Although most often associated with heart attacks and strokes, IRI also occurs when blood reperfuses a transplanted organ. Currently, monitoring for IRI is limited to biopsies, which are invasive and sample a limited area. In this work, we explored photoacoustic (PA) biomarkers of scarring. IRI events were induced in mice (n=2) by clamping the left renal artery, then re-establishing flow. At 53 days post-surgery, kidneys were saline perfused and cut in half laterally. One half was immediately imaged with a VevoX system (Fujifilm-VisualSonics, Toronto) in two near infrared ranges - 680 to 970 nm (NIR), and 1200 to 1350 nm (NIR II). The other half was decellularized and then imaged at NIR and NIR II. Regions of interest were manually identified and analyzed for each kidney. For both cellularized and decellularized samples, the PA signal ratio based on irradiation wavelengths of 715:930 nm was higher in damaged kidneys than for undamaged kidneys (p collagen in the NIR II range, while healthy kidneys did not. Collagen rich spectra were more apparent in decellularized kidneys, suggesting that in the cellularized samples, other components may be contributing to the signal. PA imaging using spectral ratios associated with collagen signatures may provide a non-invasive tool to determine areas of tissue damage due to IRIs.

  20. Estudo da isquemia e reperfusão em retalhos cutâneos de ratos The study of the ischemia and reperfusion in skin flaps of rats

    Frederico Alonso Sabino de Freitas

    2002-01-01

    Full Text Available INTRODUÇÃO: Múltiplos fatores têm sido implicados na patogênese da lesão de isquemia/reperfusão da pele, incluindo as espécies reativas de oxigênio. OBJETIVO: Estudar a lesão de isquemia/reperfusão em retalhos cutâneos de ratos avaliando os níveis teciduais do malonildialdeído (MDA e xantina oxidase (XO. MÉTODOS: Foram utilizados 8 ratos Wistar, com peso entre 300 - 400g, sendo confeccionados 2 retalhos epigástricos por animal (controle e experimento, um deles submetido à 16h de isquemia (RI seguida de 45 min de reperfusão (RR e o outro controle (RC. Foram colhidas 3 biópsias de pele dos retalhos (RC, RI, RR e encaminhadas para dosagem de MDA e XO. RESULTADOS: A análise bioquímica mostrou aumento significativo dos níveis teciduais de MDA e XO após a reperfusão em relação aos retalhos controles. CONCLUSÃO: Retalhos epigástricos de ratos submetidos à 16h de isquemia e 45min de reperfusão apresentam elevação dos níveis teciduais de MDA e XO, caracterizando a lipoperoxidação da membrana celular.INTRODUCTION: Multiple factors have been implicated in the pathogenesis of reperfusion injury in the skin, including the reactive oxygen species. OBJECTIVE: The aim was to evaluate the effect of reperfusion injury in the rat skin flap evaluated by tissue assay for malonyldialdehyde (MDA and xanthine oxidase (XO. METHODS: 8 Wistar rats were used, between 300-400g weight and two identical epigastric flaps were raised in each animal (control and experiment, the vasculature of one flap was left intact and in the second flap the arterial pedicle was clamped for 16 hours and reperfused for 45 minutes. Skin samples were obtained from each flap after these periods of time and submitted to MDA and XO analysis. RESULTS: Reperfused flaps had significantly increased MDA and XO values compared to the control flaps biopsies. CONCLUSION: The lipid peroxidation levels were higher in the rat epigastric skin flaps subjected to 16 hours of

  1. Sildenafil citrate protects skeletal muscle of ischemia-reperfusion injury: immunohistochemical study in rat model

    Dinani Matoso Fialho de Oliveira Armstrong

    2013-04-01

    Full Text Available PURPOSE: To investigate the effect of sildenafil citrate (SC on skeletal muscle ischemia-reperfusion (IR injury in rats. METHODS: Adult male Wistar rats were randomized into three groups: vehicle-treated control (CTG, sildenafil citrate-treated (SCG, and sham group (SG. CTG and SCG had femoral artery occluded for 6 hours. Saline or 1 mg/kg of SC was given 5.5 hours after occlusion. SG had a similar procedure without artery occlusion. Soleus muscle samples were acquired 4 or 24h after the reperfusion. Immunohistochemistry caspase-3 analysis was used to estimate apoptosis using the apoptotic ratio (computed as positive/negative cells. Wilcoxon rank-sum or Kruskal-Wallis tests were used to assess differences among groups. RESULTS: Eighteen animals were included in the 4h reperfusion groups and 21 animals in the 24h reperfusion groups. The mean apoptotic ratio was 0.18±0.1 for the total cohort; 0.14±0.06 for the 4h reperfusion groups and 0.19±0.08 for the 24h groups (p<0.05. The SCG had lower caspase-3 ratio compared to the control groups at the 24h reperfusion time point (p<0.05. CONCLUSION: Sildenafil citrate administration after the onset of the ischemic injury reduces IR-induced cellular damage in skeletal muscle in this rat hindlimb ischemia model.

  2. Metabolic variations of fatty acid in isolated rat heart reperfused after a transient global ischemia

    Huang Gang; Michel Comet; Zhao Huiyang; Zhu Cuiying; Yuan Jimin

    1998-01-01

    Purpose: The fatty acid metabolism and the effect of glucose on it were studied in isolated and reperfused rat heat. Methods: 32 isolated working rat hearts were perfused in Langengdorff device with modified Krebs and were divided into normal and ischemia-reperfused group. Each group was also classified into two subgroups, modified krebs with or without glucose subgroup. 131 I-HA was injected into aorta of isolated working rat heart and then the radio-residue curves were acquired. Results: When the isolated rat hearts were perfused with krebs plus glucose, the catabolism of fatty acid was significantly decreased in normal group, but a remarkable increase of fatty acid catabolism was found in ischemia-reperfused group. While the isolated rat hearts were perfused with krebs without glucose, the catabolism of fatty acid in ischemia-reperfused isolated rat hearts were perfused with krebs without glucose, the catabolism of fatty acid in ischemia-reperfused isolated rat heart was less than that in normal group. Conclusions: Transient ischemia damages the catabolism of myocardial fatty acid in mitochondria in some degree. In normal isolated working rat heart, the principal energy source is glucose. However, the major energy source is switched to catabolism of fatty acid in ischemia-reperfused isolated rat heart. This phenomenon may be related to compensative increase of fatty acid catabolism for replenishing the loss of energy during ischemia

  3. THE PROTECTIVE ROLE OF VITAMIN E AGAINST OXYGEN FREE RADICAL AND DNA DAMAGE IN CHILDREN WITH β-THALASSEMIA MAJOR

    NASSAR, E.M.

    2008-01-01

    The present study aimed to determine the benefits of vitamin E as antioxidant supplement in β thalassemia children who are at risk of iron overload due to multiple blood transfusion and oxidative stress. Antioxidant markers, oxidative products, hematological parameters and biomarkers of cell damage were studied in 24 transfusion-dependent β -thalassemia children before and after treatment with vitamin E at a dose of 10 mg/kg /day for a period of four weeks. Plasma thiobarbituric acid reactive species (TBARS) and urinary 8-hydroxy-2 ' -deoxyguanosine (8-OHdG) were analyzed as oxidative markers, whereas the plasma vitamin E and the activities of the antioxidant enzymes glutathione peroxidase (GSH-Px), superoxide dismutase(SOD) and catalase were measured to show the antioxidant status of thalassemic children. All these parameters were also studied in 15 non-anemic healthy controls .The results showed that all the patients had increased signs of iron overload and cell damage that were obvious from the increase in serum iron, ferritin, alanine transaminases (ALT), aspartate transaminases (AST) and both total and direct bilirubin .The level of plasma vitamin E in the thalassemia patients were found to be significantly lower as compared to normal subjects (1.3 ± 0.7 and 3.14 ± 1.5 mg % , respectively). The activities of antioxidants enzymes, glutathione peroxidase and catalase in untreated β-thalassemic patients were found to be significantly (P<0.001) less than that of the normal subjects. However, SOD level was significantly increased. Markers of free radical injury such as TBARS , urinary 8-OHdG levels in thalassemic children were significantly higher than control levels . All these changes in the antioxidant status as well as the hematological parameters, iron overload and cell damage markers in β-thalassemia patients showed significant improvement after vitamin E supplementation. Vitamin E levels showed significant positive correlations with each of Hb, GSH

  4. Chronic heat improves mechanical and metabolic response of trained rat heart on ischemia and reperfusion.

    Levy, E; Hasin, Y; Navon, G; Horowitz, M

    1997-05-01

    Cardiac mechanics and metabolic performance were studied in isolated perfused hearts of rats subjected to a combined chronic stress of heat acclimation and swimming training (EXAC) or swimming training alone (EX). Diastolic (DP) and systolic pressures (SP), coronary flow (CF), and oxygen consumption were measured during normoperfusion (80 mmHg), and the appearance of ischemic contracture (IC), DP, and SP were measured during progressive graded ischemia, total ischemia (TI), and reperfusion insults. ATP, phosphocreatine, and intracellular pH were measured during TI and reperfusion with 31P nuclear magnetic resonance spectroscopy. During normoperfusion, SP and cardiac efficiency (derived from rate-pressure product-oxygen consumption relationships) were the highest in the 2-mo EXAC hearts (P pool and there was a delayed decline in intracellular pH. On reperfusion, these hearts also displayed improved ATP and phosphocreatine recovery, the 2-mo EXAC heart demonstrating significantly faster high-energy phosphate salvage, improved diastolic function, and pulse pressure recovery. The data attest to the beneficial effects of heat acclimation on cardiac mechanics of trained rats during normoperfusion and cardiac protection on ischemia and reperfusion. Possibly, energy sparing, lesser acidosis, and shorter duration of IC on ischemia and improved energy salvage on reperfusion contribute synergistically to this potent beneficial effect.

  5. Activated protein C attenuates acute ischaemia reperfusion injury in skeletal muscle.

    Dillon, J P

    2012-02-03

    Activated protein C (APC) is an endogenous anti-coagulant with anti-inflammatory properties. The purpose of the present study was to evaluate the effects of activated protein C in the setting of skeletal muscle ischaemia reperfusion injury (IRI). IRI was induced in rats by applying rubber bands above the levels of the greater trochanters bilaterally for a period of 2h followed by 12h reperfusion. Treatment groups received either equal volumes of normal saline or activated protein C prior to tourniquet release. Following 12h reperfusion, muscle function was assessed electrophysiologically by electrical field stimulation. The animals were then sacrificed and skeletal muscle harvested for evaluation. Activated protein C significantly attenuated skeletal muscle reperfusion injury as shown by reduced myeloperoxidase content, wet to dry ratio and electrical properties of skeletal muscle. Further in vitro work was carried out on neutrophils isolated from healthy volunteers to determine the direct effect of APC on neutrophil function. The effects of APC on TNF-alpha stimulated neutrophils were examined by measuring CD18 expression as well as reactive oxygen species generation. The in vitro work demonstrated a reduction in CD18 expression and reactive oxygen species generation. We conclude that activated protein C may have a protective role in the setting of skeletal muscle ischaemia reperfusion injury and that this is in part mediated by a direct inhibitory effect on neutrophil activation.

  6. Ameliorating reactive oxygen species-induced in vitro lipid peroxidation in brain, liver, mitochondria and DNA damage by Zingiber officinale Roscoe.

    Ajith, T A

    2010-01-01

    Iron is an essential nutrient for a number of cellular activities. However, excess cellular iron can be toxic by producing reactive oxygen species (ROS) such as superoxide anion (O(2) (-)) and hydroxyl radical (HO(·)) that damage proteins, lipids and DNA. Mutagenic and genotoxic end products of lipid peroxidation can induce the decline of mitochondrial respiration and are associated with various human ailments including aging, neurodegenerative disorders, cancer etc. Zingiber officinale Roscoe (ginger) is a widely used spice around the world. The protective effect of aqueous ethanol extract of Z. officinale against ROS-induced in vitro lipid peroxidation and DNA damage was evaluated in this study. The lipid peroxidation was induced by hydroxyl radical generated from Fenton's reaction in rat liver and brain homogenates and mitochondrial fraction (isolated from rat liver). The DNA protection was evaluated using H(2)O(2)-induced changes in pBR-322 plasmid and Fenton reaction-induced DNA fragmentation in rat liver. The results indicated that Z. officinale significantly (Pofficinale in the liver homogenate was 94 %. However, the extract could partially alleviate the DNA damage. The protective mechanism can be correlated to the radical scavenging property of Z. officinale. The results of the study suggest the possible nutraceutical role of Z. officinale against the oxidative stress induced human ailments.

  7. Study of gamma radiation induced damages and variation of oxygen enhancement ratio with radiation dose using Saccharomyces cerevisiae

    Nairy, R.K.; Yerol Narayana; Bhat, N.N.; Anjaria, K.B.; Sreedevi, B.; Sapra, B.K.

    2014-01-01

    In the present study, an attempt has been made to quantify Oxygen Enhancement Ratio (OER) and variation of OER as a function of dose with experimental and theoretical formulations using Saccharomyces cerevisiae D7, X2180 and rad 52. The study confirms that, the variation of OER with dose depends upon type of cell and repair proficiency of cells. A theoretical model has been formulated to estimate OER values. With the help of this model, OER value for any dose can be calculated in the exponential region of the survival curve without actually extending the experiment in that dose region. (author)

  8. Protective Effects of Flavonoid Pomiferin on Heart Ischemia-Reperfusion

    J. Nečas

    2007-01-01

    Full Text Available The objective of the present 15-day study was to evaluate the cardioprotective potential of flavonoid pomiferin isolated from the infructences of Maclura pomifera, Moraceae, against ischemia-reperfusion induced injury in rat hearts as a model of antioxidant-based composite therapy. Studies were performed with isolated, modifi ed Langendorff-perfused rat hearts and ischemia of heart was initiated by stopping the coronary flow for 30 min, followed by 60 min of reperfusion (14 ml min-1. Wistar rats were divided into three groups. The treated group received pomiferin (5 mg/kg/day in 0.5% Avicel; the placebo group received only 0.5% Avicel; the intact group was left without any applications. Biochemical indicators of oxidative damage, lipid peroxidation product malondialdehyde, antioxidant enzymes (superoxide dismutase, glutathione peroxidase, total antioxidant activity in serum and myocardium has been evaluated. We also examined the effect of pomiferin on cardiac function (left ventricular end-diastolic pressure, left ventricular pressure, peak positive +dP/dt (rate of pressure development after ischemia and reperfusion. Our results demonstrate that pomiferin attenuates the myocardial dysfunction provoked by ischemiareperfusion. This was confirmed by the increase in both the antioxidant enzyme values and the total antioxidant activity. The cardio-protection provided by pomiferin treatment results from the suppression of oxidative stress and correlates with the improved ventricular function.

  9. Effects of hyperbaric oxygen and nerve growth factor on the long-term neural behavior of neonatal rats with hypoxic ischemic brain damage.

    Wei, Lixia; Ren, Qing; Zhang, Yongjun; Wang, Jiwen

    2017-04-01

    To evaluate the effects of HBO (Hyperbaric oxygen) and NGF (Nerve growth factor) on the long-term neural behavior of neonatal rats with HIBD (Neonatal hypoxic ischemic brain damage). The HIBD model was produced by ligating the right common carotid artery of 7 days old SD (Sprague-Dawley) rats followed by 8% O2 + 92% N2 for 2h. Totally 40 rats were randomly divided into 5 groups including sham-operated group, HIBD control group, HBO treated group, NGF treated group and NGF + HBO treated group. The learning and memory ability of these rats was evaluated by Morris water maze at 30 days after birth, and sensory motor function was assessed by experiments of foot error and limb placement at 42 days after birth. The escape latency of HBO treated group, NGF treated group and NGF + HBO treated group was shorter than that of HIBD control group (pmemory ability and sensory motor function in neonatal rats after hypoxic ischemic brain damage.

  10. Influence of oxygen on the repair of direct radiation damage to DNA by thiols in model systems

    Becker, D.; Summerfield, S.; Gillich, S.; Sevilla, M.D.

    1994-01-01

    Here the reactions of thiols with DNA primary radical intermediates formed after γ-irradiation of frozen (77K) anoxic and oxic solutions of DNA/thiol mixtures are investigated. Through analysis of the experimental composite spectra at each annealing temperature, the relative concentrations of individual radicals present are estimated and reaction sequences inferred. In all samples the primary DNA radical anions and cations (DNA · + and DNA · - ) are suggested to be the predominant radicals at low temperatures. In anoxic samples, TH · (5,6-dihydrothym-5-yl radical), RSSR · - and, in glutathione samples, · GSH [γ-glu-NHC(CH 2 SH) CO-gly] radicals are observed as the temperature is increased. The presence of oxygen efficiently suppresses the formation of RSSR · - and · GSH; instead, in oxic samples, O 2 · - , DNAOO · , RSOO · and RSO · are observed at higher temperatures. The photolytic conversion of RSOO · to RSO 2 · is used to verify the presence of RSOO · in γ-irradiated DNA/thiol systems and confirm that the computer analysis employed yields reasonable estimates of the relative DNAOO · and RSOO · concentrations. (Author)

  11. Aag-initiated base excision repair promotes ischemia reperfusion injury in liver, brain, and kidney.

    Ebrahimkhani, Mohammad R; Daneshmand, Ali; Mazumder, Aprotim; Allocca, Mariacarmela; Calvo, Jennifer A; Abolhassani, Nona; Jhun, Iny; Muthupalani, Sureshkumar; Ayata, Cenk; Samson, Leona D

    2014-11-11

    Inflammation is accompanied by the release of highly reactive oxygen and nitrogen species (RONS) that damage DNA, among other cellular molecules. Base excision repair (BER) is initiated by DNA glycosylases and is crucial in repairing RONS-induced DNA damage; the alkyladenine DNA glycosylase (Aag/Mpg) excises several DNA base lesions induced by the inflammation-associated RONS release that accompanies ischemia reperfusion (I/R). Using mouse I/R models we demonstrate that Aag(-/-) mice are significantly protected against, rather than sensitized to, I/R injury, and that such protection is observed across three different organs. Following I/R in liver, kidney, and brain, Aag(-/-) mice display decreased hepatocyte death, cerebral infarction, and renal injury relative to wild-type. We infer that in wild-type mice, Aag excises damaged DNA bases to generate potentially toxic abasic sites that in turn generate highly toxic DNA strand breaks that trigger poly(ADP-ribose) polymerase (Parp) hyperactivation, cellular bioenergetics failure, and necrosis; indeed, steady-state levels of abasic sites and nuclear PAR polymers were significantly more elevated in wild-type vs. Aag(-/-) liver after I/R. This increase in PAR polymers was accompanied by depletion of intracellular NAD and ATP levels plus the translocation and extracellular release of the high-mobility group box 1 (Hmgb1) nuclear protein, activating the sterile inflammatory response. We thus demonstrate the detrimental effects of Aag-initiated BER during I/R and sterile inflammation, and present a novel target for controlling I/R-induced injury.

  12. Protective Effect of Extract of Folium Ginkgo on Repeated Cerebral Ischemia-Reperfusion Injury

    2000-01-01

    Objective: To study the protective effect of extract of Folium Ginkgo (FGE) on repeated cerebral ischemia-reperfusion injury. Methods: The model in waking mice induced by repeated cerebral ischemia-reperfusion were used in the experiment to observe the effect of FGE on behavior, oxygen free radical metabolism and prostaglandin E2 (PGE2) content by step-through experiment, diving stand and colorimetric method. Results: FGE could obviously improve the learning ability and memory of model animals, and could lower obviously the content of malonyldialdehyde, nitric oxide and PGE2, restore the lowered activity of superoxide dismutase and catalase in cerebral tissue. Conclusion: FGE has highly protective effect against repeated ischemia-reperfusion injury, the mechanism might be related with its action on anti-lipid oxidatin, improve the activity of antioxidase and inhibit the producing of PGE2.

  13. Role of neuronal and inducible nitric oxide synthases in the guinea pig ileum myenteric plexus during in vitro ischemia and reperfusion.

    Giaroni, C; Marchet, S; Carpanese, E; Prandoni, V; Oldrini, R; Bartolini, B; Moro, E; Vigetti, D; Crema, F; Lecchini, S; Frigo, G

    2013-02-01

    Intestinal ischemia and reperfusion (I/R) injury leads to abnormalities in motility, namely delay of transit, caused by damage to myenteric neurons. Alterations of the nitrergic transmission may occur in these conditions. This study investigated whether an in vitro I/R injury may affect nitric oxide (NO) production from the myenteric plexus of the guinea pig ileum and which NO synthase (NOS) isoform is involved. The distribution of the neuronal (n) and inducible (i) NOS was determined by immunohistochemistry during 60 min of glucose/oxygen deprivation (in vitro ischemia) followed by 60 min of reperfusion. The protein and mRNA levels of nNOS and iNOS were investigated by Western-immunoblotting and real time RT-PCR, respectively. NO levels were quantified as nitrite/nitrate. After in vitro I/R the proportion of nNOS-expressing neurons and protein levels remained unchanged. nNOS mRNA levels increased 60 min after inducing ischemia and in the following 5 min of reperfusion. iNOS-immunoreactive neurons, protein and mRNA levels were up-regulated during the whole I/R period. A significant increase of nitrite/nitrate levels was observed in the first 5 min after inducing I/R and was significantly reduced by N(ω) -propyl-l-arginine and 1400 W, selective inhibitors of nNOS and iNOS, respectively. Our data demonstrate that both iNOS and nNOS represent sources for NO overproduction in ileal myenteric plexus during I/R, although iNOS undergoes more consistent changes suggesting a more relevant role for this isoform in the alterations occurring in myenteric neurons following I/R. © 2012 Blackwell Publishing Ltd.

  14. Effect of total flavonoids of Radix Ilicis pubescentis on cerebral ischemia reperfusion model

    Xiaoli Yan

    2017-03-01

    Full Text Available This paper aims to observe the effects of total flavonoids of Radix Ilicis pubescentis on mouse model of cerebral ischemia reperfusion. Mice were orally given different doses of total flavonoids of Radix Ilicis pubescentis 10 d, and were administered once daily. On the tenth day after the administration of 1 h in mice after anesthesia, we used needle to hook the bilateral common carotid artery (CCA for 10 min, with 10 min ischemia reperfusion, 10 min ischemia. Then we restored their blood supply, copy the model of cerebral ischemia reperfusion; We then had all mice reperfused for 24 h, and then took their orbital blood samples and measured blood rheology. We quickly removed the brain, with half of the brain having sagittal incision. Then we fixed the brains and sectioned them to observe the pathological changes of brain cells in the hippocampus and cortex. We also measured the other half sample which was made of brain homogenate of NO, NOS, Na+-K+-, ATP enzyme Mg2+-ATPase and Ca2+-ATPase. Acupuncture needle hook occlusion of bilateral common carotid arteries can successfully establish the model of cerebral ischemia reperfusion. After comparing with the model mice, we concluded that Ilex pubescens flavonoids not only reduce damage to the brain nerve cells in the hippocampus and cortex, but also significantly reduce the content of NO in brain homogenate, the activity of nitric oxide synthase (NOS and increases ATP enzyme activity (P < 0.05, P < 0.01. In this way, cerebral ischemia reperfusion injury is improved. Different dosages of Ilex pubescens flavonoids on mouse cerebral ischemia reperfusion model have good effects.

  15. Oxygen and oxidative stress in the perinatal period

    Isabel Torres-Cuevas

    2017-08-01

    Full Text Available Fetal life evolves in a hypoxic environment. Changes in the oxygen content in utero caused by conditions such as pre-eclampsia or type I diabetes or by oxygen supplementation to the mother lead to increased free radical production and correlate with perinatal outcomes.In the fetal-to-neonatal transition asphyxia is characterized by intermittent periods of hypoxia ischemia that may evolve to hypoxic ischemic encephalopathy associated with neurocognitive, motor, and neurosensorial impairment. Free radicals generated upon reoxygenation may notably increase brain damage. Hence, clinical trials have shown that the use of 100% oxygen given with positive pressure in the airways of the newborn infant during resuscitation causes more oxidative stress than using air, and increases mortality.Preterm infants are endowed with an immature lung and antioxidant system. Clinical stabilization of preterm infants after birth frequently requires positive pressure ventilation with a gas admixture that contains oxygen to achieve a normal heart rate and arterial oxygen saturation. In randomized controlled trials the use high oxygen concentrations (90% to 100% has caused more oxidative stress and clinical complications that the use of lower oxygen concentrations (30–60%. A correlation between the amount of oxygen received during resuscitation and the level of biomarkers of oxidative stress and clinical outcomes was established. Thus, based on clinical outcomes and analytical results of oxidative stress biomarkers relevant changes were introduced in the resuscitation policies. However, it should be underscored that analysis of oxidative stress biomarkers in biofluids has only been used in experimental and clinical research but not in clinical routine. The complexity of the technical procedures, lack of automation, and cost of these determinations have hindered the routine use of biomarkers in the clinical setting. Overcoming these technical and economical difficulties

  16. Hydrogen sulfide intervention in focal cerebral ischemia/reperfusion injury in rats

    Xin-juan Li

    2015-01-01

    Full Text Available The present study aimed to explore the mechanism underlying the protective effects of hydrogen sulfide against neuronal damage caused by cerebral ischemia/reperfusion. We established the middle cerebral artery occlusion model in rats via the suture method. Ten minutes after middle cerebral artery occlusion, the animals were intraperitoneally injected with hydrogen sulfide donor compound sodium hydrosulfide. Immunofluorescence revealed that the immunoreactivity of P2X 7 in the cerebral cortex and hippocampal CA1 region in rats with cerebral ischemia/reperfusion injury decreased with hydrogen sulfide treatment. Furthermore, treatment of these rats with hydrogen sulfide significantly lowered mortality, the Longa neurological deficit scores, and infarct volume. These results indicate that hydrogen sulfide may be protective in rats with local cerebral ischemia/reperfusion injury by down-regulating the expression of P2X 7 receptors.

  17. Reactive oxygen species mediated DNA damage in human lung alveolar epithelial (A549) cells from exposure to non-cytotoxic MFI-type zeolite nanoparticles.

    Bhattacharya, Kunal; Naha, Pratap C; Naydenova, Izabela; Mintova, Svetlana; Byrne, Hugh J

    2012-12-17

    Increasing utilization of engineered nanoparticles in the field of electronics and biomedical applications demands an assessment of risk associated with deliberate or accidental exposure. Metal based nanoparticles are potentially most important of all the nanoparticles in terms of health risks. Microporous alumino-silicates and pure silicates named as zeolites and zeo-type materials with variety of structures, chemical compositions, particle sizes and morphologies have a significant number of industrial uses such as in catalysis, sorption and ion-exchange processes. In particular, the nanosized particles due to their unique properties are used in hybrid organic-inorganic materials for photography, photonics, electronics, labeling, imaging, and sensing. The aim of the current study is to investigate pure silica MFI-type zeolites nanoparticles with sizes of 50nm and 100nm (samples MFI-50 and MFI-100) under suspended conditions and their toxicological effects on human lung alveolar (A549) cells under in vitro conditions. Live cell imaging showed that the nanoparticles precipitated from the colloidal suspension of cell culture media as large agglomerates, coming in contact with the cell surface through sedimentation. A cellular proliferative capacity test showed the zeolite nanoparticles to exhibit no significant cytotoxicity below a concentration of 100μg/ml. However, both the MFI-50 and MFI-100 nanoparticles induced high intracellular reactive oxygen species (ROS) generation and elevated mitochondrial membrane potential in the A549 cells over the measured time period of 12h and at concentrations up to ≤50μg/ml. DNA fragmentation analysis using the comet assay showed that the MFI-50 and MFI-100 nanoparticles cause genotoxicity in a concentration dependent manner. Furthermore, the rate at which maximum genomic damage was caused by MFI-100 nanoparticles in the A549 cells was found to be high as compared to the MFI-50 nanoparticles. However, the damage caused by the

  18. Effect of Cuscuta chinensis on renal function in ischemia/reperfusion-induced acute renal failure rats.

    Shin, Sun; Lee, Yun Jung; Kim, Eun Ju; Lee, An Sook; Kang, Dae Gill; Lee, Ho Sub

    2011-01-01

    The kidneys play a central role in regulating water, ion composition and excretion of metabolic waste products in the urine. Cuscuta chinensis has been known as an important traditional Oriental medicine for the treatment of liver and kidney disorders. Thus, we studied whether an aqueous extract of Cuscuta chinensis (ACC) seeds has an effect on renal function parameters in ischemia/reperfusion-induced acute renal failure (ARF) rats. Administration of 250 mg/kg/day ACC showed that renal functional parameters including urinary excretion rate, osmolality, Na(+), K(+), Cl(-), creatinine clearance, solute-free water reabsorption were significantly recovered in ischemia/reperfusion-induced ARF. Periodic acid Schiff staining showed that administration of ACC improved tubular damage in ischemia/reperfusion-induced ARF. In immunoblot and immunohistological examinations, ischemia/reperfusion-induced ARF decreased the expressions of water channel AQP 2, 3 and sodium potassium pump Na,K-ATPase in the renal medulla. However, administration of ACC markedly incremented AQP 2, 3 and Na,K-ATPase expressions. Therefore, these data indicate that administration of ACC ameliorates regulation of the urine concentration and renal functions in rats with ischemia/reperfusion-induced ARF.

  19. Study on pretreatment of FPS-1 in rats with hepatic ischemia-reperfusion injury.

    Lin, Shiqing; Liu, Kexuan; Wu, Weikang; Chen, Chao; Wang, Zhi; Zhang, Xuanhong

    2009-01-01

    This study was designed to determine whether FPS-1, the water-soluble polysaccharide isolated from fuzi, protected against hepatic damage in hepatic ischemia-reperfusion injury in rats, and its mechanism. SD rats were subjected to 60 min of hepatic ischemia, followed by 120 min reperfusion. FPS-1 (160 mg/kg/day) was administered orally for 5 days before ischemia-reperfusion injury in treatment group. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and albumin (ALB) were assayed to evaluate liver functions. Liver samples were taken for histological examination and determination of malondialdehyde (MDA), superoxide dismutase (SOD), that catalase (CAT) in liver. Na(+)-K(+)-ATPase and Ca(2+)-ATPase in mitochondria were measured with colorimetry method. Morphological changes were also investigated by using both light microscopy and electron microscopy (EM). In addition, apoptosis and oncosis were detected by Annexin V-FITC/PI immunofluorescent flow cytometry analysis. Serum AST and ALT levels were elevated in groups exposed to ischemia-reperfusion (p FPS-1 reversed all these biochemical parameters as well as histological alterations, evidently by increased SOD, CAT, reduced MDA and histological scores compared to the model group (p FPS-1 could attenuate the necrotic states by the detection of immunofluorescent flow cytometry analysis. Pretreatment with FPS-1 reduced hepatic ischemia-reperfusion injury through its potent antioxidative effects and attenuation of necrotic states.

  20. Intestinal ischemia-reperfusion injury augments intestinal mucosal injury and bacterial translocation in jaundiced rats.

    Yüksek, Yunus Nadi; Kologlu, Murat; Daglar, Gül; Doganay, Mutlu; Dolapci, Istar; Bilgihan, Ayse; Dolapçi, Mete; Kama, Nuri Aydin

    2004-01-01

    The aim of this study was to evaluate local effects and degree of bacterial translocation related with intestinal ischemia-reperfusion injury in a rat obstructive jaundice model. Thirty adult Sprague-Dawley rats (200-250 g) were divided into three groups; including Group 1 (jaundice group), Group 2 (jaundice-ischemia group) and Group 3 (ischemia group). All rats had 2 laparotomies. After experimental interventions, tissue samples for translocation; liver and ileum samples for histopathological examination, 25 cm of small intestine for mucosal myeloperoxidase and malondialdehyde levels and blood samples for biochemical analysis were obtained. Jaundiced rats had increased liver enzyme levels and total and direct bilirubin levels (p<0.05). Intestinal mucosal myeloperoxidase and malondialdehyde levels were found to be high in intestinal ischemia-reperfusion groups (p<0.05). Intestinal mucosal damage was more severe in rats with intestinal ischemia-reperfusion after bile duct ligation (p<0.05). Degree of bacterial translocation was also found to be significantly high in these rats (p<0.05). Intestinal mucosa is disturbed more severely in obstructive jaundice with the development of ischemia and reperfusion. Development of intestinal ischemia-reperfusion in obstructive jaundice increases bacterial translocation.

  1. Dynamic alteration of the colonic microbiota in intestinal ischemia-reperfusion injury.

    Fan Wang

    Full Text Available Intestinal ischemia-reperfusion (I/R plays an important role in critical illnesses. Gut flora participate in the pathogenesis of the injury. This study is aimed at unraveling colonic microbiota alteration pattern and identifying specific bacterial species that differ significantly as well as observing colonic epithelium change in the same injury model during the reperfusion time course.Denaturing gradient gel electrophoresis (DGGE was used to monitor the colonic microbiota of control rats and experimental rats that underwent 0.5 hour ischemia and 1, 3, 6, 12, 24, and 72 hours following reperfusion respectively. The microbiota similarity, bacterial diversity and species that characterized the dysbiosis were estimated based on the DGGE profiles using a combination of statistical approaches. The interested bacterial species in the gel were cut and sequenced and were subsequently quantified and confirmed with real-time PCR. Meanwhile, the epithelial barrier was checked by microscopy and D-lactate analysis. Colonic flora changed early and differed significantly at 6 hours after reperfusion and then started to recover. The shifts were characterized by the increase of Escherichia coli and Prevotella oralis, and Lactobacilli proliferation together with epithelia healing.This study shows for the first time that intestinal ischemia-reperfusion results in colonic flora dysbiosis that follows epithelia damage, and identifies the bacterial species that contribute most.

  2. Carbon monoxide-Releasing Molecule-2 (CORM-2 attenuates acute hepatic ischemia reperfusion injury in rats

    Zhang Weihui

    2010-05-01

    Full Text Available Abstract Background Hepatic ischemia-reperfusion injury (I/Ri is a serious complication occurring during liver surgery that may lead to liver failure. Hepatic I/Ri induces formation of reactive oxygen species, hepatocyte apoptosis, and release of pro-inflammatory cytokines, which together causes liver damage and organ dysfunction. A potential strategy to alleviate hepatic I/Ri is to exploit the potent anti-inflammatory and cytoprotective effects of carbon monoxide (CO by application of so-called CO-releasing molecules (CORMs. Here, we assessed whether CO released from CORM-2 protects against hepatic I/Ri in a rat model. Methods Forty male Wistar rats were randomly assigned into four groups (n = 10. Sham group underwent a sham operation and received saline. I/R group underwent hepatic I/R procedure by partial clamping of portal structures to the left and median lobes with a microvascular clip for 60 minutes, yielding ~70% hepatic ischemia and subsequently received saline. CORM-2 group underwent the same procedure and received 8 mg/kg of CORM-2 at time of reperfusion. iCORM-2 group underwent the same procedure and received iCORM-2 (8 mg/kg, which does not release CO. Therapeutic effects of CORM-2 on hepatic I/Ri was assessed by measuring serum damage markers AST and ALT, liver histology score, TUNEL-scoring of apoptotic cells, NFkB-activity in nuclear liver extracts, serum levels of pro-inflammatory cytokines TNF-α and IL-6, and hepatic neutrophil infiltration. Results A single systemic infusion with CORM-2 protected the liver from I/Ri as evidenced by a reduction in serum AST/ALT levels and an improved liver histology score. Treatment with CORM-2 also up-regulated expression of the anti-apoptotic protein Bcl-2, down-regulated caspase-3 activation, and significantly reduced the levels of apoptosis after I/Ri. Furthermore, treatment with CORM-2 significantly inhibited the activity of the pro-inflammatory transcription factor NF-κB as measured in

  3. Meclofenamic Acid Reduces Reactive Oxygen Species Accumulation and Apoptosis, Inhibits Excessive Autophagy, and Protects Hair Cell-Like HEI-OC1 Cells From Cisplatin-Induced Damage

    He Li

    2018-05-01

    Full Text Available Hearing loss is the most common sensory disorder in humans, and a significant number of cases is due to the ototoxicity of drugs such as cisplatin that cause hair cell (HC damage. Thus, there is great interest in finding agents and mechanisms that protect HCs from ototoxic drug damage. It has been proposed that epigenetic modifications are related to inner ear development and play a significant role in HC protection and HC regeneration; however, whether the m6A modification and the ethyl ester form of meclofenamic acid (MA2, which is a highly selective inhibitor of FTO (fatmass and obesity-associated enzyme, one of the primary human demethylases, can affect the process of HC apoptosis induced by ototoxic drugs remains largely unexplored. In this study, we took advantage of the HEI-OC1 cell line, which is a cochlear HC-like cell line, to investigate the role of epigenetic modifications in cisplatin-induced cell death. We found that cisplatin injury caused reactive oxygen species accumulation and increased apoptosis in HEI-OC1 cells, and the cisplatin injury was reduced by co-treatment with MA2 compared to the cisplatin-only group. Further investigation showed that MA2 attenuated cisplatin-induced oxidative stress and apoptosis in HEI-OC1 cells. We next found that the cisplatin-induced upregulation of autophagy was significantly inhibited after MA2 treatment, indicating that MA2 inhibited the cisplatin-induced excessive autophagy. Our findings show that MA2 has a protective effect and improves the viability of HEI-OC1 cells after cisplatin treatment, and they provide new insights into potential therapeutic targets for the amelioration of cisplatin-induced ototoxicity.

  4. Prophylactic Treatment with Cerium Oxide Nanoparticles Attenuate Hepatic Ischemia Reperfusion Injury in Sprague Dawley Rats

    Nandini D.P.K. Manne

    2017-07-01

    Full Text Available Background: Hepatic ischemia reperfusion is one the main causes for graft failure following transplantation. Although, the molecular events that lead to hepatic failure following ischemia reperfusion (IR are diverse and complex, previous studies have shown that excessive formation of reactive oxygen species (ROS are responsible for hepatic IR injury. Cerium oxide (CeO2 nanoparticles have been previously shown to act as an anti-oxidant and anti-inflammatory agent. Here, we evaluated the protective effects of CeO2 nanoparticles on hepatic ischemia reperfusion injury. Methods: Male Sprague Dawley rats were randomly assigned to one of the four groups: Control, CeO2 nanoparticle only, hepatic ischemia reperfusion (IR group and hepatic ischemia reperfusion (IR plus CeO2 nanoparticle group (IR+ CeO2. Partial warm hepatic ischemia was induced in left lateral and median lobes for 1h, followed by 6h of reperfusion. Animals were sacrificed after 6h of reperfusion and blood and tissue samples were collected and processed for various biochemical experiments. Results: Prophylactic treatment with CeO2 nanoparticles (0.5mg/kg i.v (IR+CeO2 group 1 hour prior to hepatic ischemia and subsequent reperfusion injury lead to a decrease in serum levels of alanine aminotransaminase and lactate dehydrogenase at 6 hours after reperfusion. These changes were accompanied by significant decrease in hepatocyte necrosis along with reduction in several serum inflammatory markers such as macrophage derived chemokine, macrophage inflammatory protein-2, KC/GRO, myoglobin and plasminogen activator inhibitor-1. However, immunoblotting demonstrated no significant changes in the levels of apoptosis related protein markers such as bax, bcl2 and caspase 3 in IR and IR+ CeO2 groups at 6 hours suggesting necrosis as the main pathway for hepatocyte death. Conclusion: Taken together, these data suggest that CeO2 nanoparticles attenuate IR induced cell death and can be used as a prophylactic

  5. Role of Calcium Sensing Receptor in Streptozotocin-Induced Diabetic Rats Exposed to Renal Ischemia Reperfusion Injury

    Bo Hu

    2018-02-01

    Full Text Available Background/Aims: Renal ischemia/reperfusion (I/R injury (RI/RI is a common complication of diabetes, and it may be involved in altering intracellular calcium concentrations at its onset, which can result in inflammation, abnormal lipid metabolism, the production of reactive oxygen species (ROS, and nitroso-redox imbalance. The calcium-sensing receptor (CaSR is a G-protein coupled receptor, however, the functional involvement of CaSR in diabetic RI/ RI remains unclear. The present study was intended to investigate the role of CaSR on RI/RI in diabetes mellitus (DM. Methods: The bilateral renal arteries and veins of streptozotocin (STZ-induced diabetic rats were subjected to 45-min ischemia followed by 2-h reperfusion with or without R-568 (agonist of CaSR and NPS-2143 (antagonist of CaSR at the beginning of I/R procedure. DM without renal I/R rats served as control group. The expressions of CaSR, calmodulin (CaM, and p47phox in the renal tissue were analyzed by qRT-PCR and Western blot. The renal pathomorphology, renal function, oxidative stress, inflammatory response, and calcium disorder were evaluated by detection of a series of indices by hematoxylin-eosin (HE staining, transmission electron microscope (TEM, commercial kits, enzyme-linked immunosorbent assay (ELISA, and spectrophotofluorometry, respectively. Results: Results showed that the expressions of CaSR, CaM, and p47phox in I/R group were significantly up-regulated as compared with those in DM group, which were accompanied by renal tissue injury, increased calcium, oxidative stress, inflammation, and nitroso-redox imbalance. Conclusion: These results suggest that activation of CaSR is involved in the induction of damage of renal tubular epithelial cell during diabetic RI/RI, resulting in lipid peroxidation, inflammatory response, nitroso-redox imbalance, and apoptosis.

  6. Effects of signal transducer and activator of transcription 3 RNAi on content of reactive oxygen species and DNA damage in glioma cell

    Gao Ling; Li Fengsheng; Dong Bo; Liu Lihui; Liu Qingjie; Chen Xiaohua; Mao Bingzhi

    2011-01-01

    Objective: To investigate the effects of signal transducer and activator of transcription 3 (STAT3) RNAi on the content of reactive oxygen species (ROS) and the DNA damage in glioma cells. Methods: Glioma cells of the line U251 cells were cultured and transfected with STAT3 RNAi plasmid (pSilencer2.1-STAT3, STAT3 group) and pSilencer2.1-GFP (GFP control group) respectively. Part of the U251 cells were irradiated with γ-rays of 60 Co as positive control group of smear phenomenon. The levels of ROS and malondialdehyde (MDA) in the cells were detected 24, 48, and 72 h later by flow cytometry and fluorescence chamoluminescence analyzer, respectively. The DNA damage in the transfected U251 cells was examined by using single cell gel electrophoresis assay, and the cell cycle distribution was examined using FACS PI staining 12, 24, and 36 h later. Results: At 24 h after the transfection, the ROS level of the siSTAT3-transfected cells was 8.91 times that of the control group (F=89.296, P<0.05), and returned to the normal level 48 h later. There were not significant differences in the MDA level of the cells 24, 48, and 72 h later between the siSTAT3 group and siGFP group. Compared with the 8 Gy irradiation positive group with obvious smear phenomenon, smear phenomenon was shown in part of the cells in the siSTAT3 group 6 h later, became less 12 h later, and disappeared completely 24 h later. Compared with the control group,lag of S stage rate was 17.22% and the lag of G 2 /M stage rate was 6.4% 12 h later in the siSTAT-transfected group,and the G 0 /G 1 stage lag rate was 18.44% 24 h later, and the lag of S stage rate was 17.99% 36 h later. Conclusions: Inhibition of STAT3 results in the change of oxido reduction status in glioma cells, as well as damage and reparation of DNA. (authors)

  7. Evaluation of Pulmonary Reperfusion Injury in Rats Undergoing Mesenteric Ischemia and Reperfusion and Protective Effect of Postconditioning on this Process

    Carlos Henrique Marques dos Santos

    2015-10-01

    Full Text Available ABSTRACT INTRODUCTION: Some publications have demonstrated the presence of lung reperfusion injury in mesenteric ischemia and reperfusion (I/R, but under to diverse methods. Postconditioning has been recognized as effective in preventing reperfusion injury in various organs and tissues. However, its effectiveness has not been evaluated in the prevention of lung reperfusion injury after mesenteric ischemia and reperfusion. OBJECTIVE: To evaluate the presence of pulmonary reperfusion injury and the protective effect of ischemic postconditioning on lung parenchyma in rats submitted to mesenteric ischemia and reperfusion. METHODS: Thirty Wistar rats were distributed into three groups: group A (10 rats, which was held mesenteric ischemia (30 minutes and reperfusion (60 minutes; group B (10 rats, ischemia and reperfusion, interspersed by postconditioning with two alternating cycles of reperfusion and reocclusion, for two minutes each; and group C (10 rats, ischemia and reperfusion interleaved by postconditioning with four alternating cycles of reperfusion and reocclusion of 30 seconds each. Finally, it was resected the upper lung lobe for histological analysis. RESULTS: There were mild lung lesions (grade 1 in all samples. There was no statistical difference between groups 1 and 2 (P >0.05. CONCLUSION: The mesenteric ischemia and reperfusion in rats for thirty and sixty minutes, respectively, caused mild reperfusion injury in lung. Postconditioning was not able to minimize the remote reperfusion injury and there was no difference comparing two cycles of two minutes with four cycles of 30 seconds.

  8. Dual Gas Treatment With Hydrogen and Carbon Monoxide Attenuates Oxidative Stress and Protects From Renal Ischemia-Reperfusion Injury.

    Nishida, T; Hayashi, T; Inamoto, T; Kato, R; Ibuki, N; Takahara, K; Takai, T; Yoshikawa, Y; Uchimoto, T; Saito, K; Tanda, N; Kouno, J; Minami, K; Uehara, H; Hirano, H; Nomi, H; Okada, Y; Azuma, H

    Hydrogen (H 2 ) and carbon monoxide (CO) gas are both reported to reduce reactive oxygen species and alleviate tissue ischemia-reperfusion (I-R) injury. The present study was conducted to evaluate the effects of a mixture of H 2 gas and CO gas (dual gas) in comparison with hydrogen gas (H 2 : 2%) alone on I-R renal injury (composition of dual gas; N 2 : 77.8%; O 2 : 20.9%; H 2 : 1.30%; CO: 250 parts per million). Adult male Sprague-Dawley rats (body weight 250-280 g) were divided into 5 groups: (1) sham operation control, (2) dual gas inhalation (dual treatment) without I-R treatment, (3) I-R renal injury, (4) H 2 gas alone inhalation (H 2 treatment) with I-R renal injury, and (5) dual treatment with I-R renal injury. I-R renal injury was induced by clamping the left renal artery and vein for 45 minutes followed by reperfusion, and then contralateral nephrectomy was performed 2 weeks later. Renal function was markedly decreased at 24 hours after reperfusion, and thereafter the effects of dual gas were assessed by histologic examination and determination of the superoxide radical, together with functional and molecular analyses. Pathologic examination of the kidney of I-R rats revealed severe renal damage. Importantly, cytoprotective effects of the dual treatment in comparison with H 2 treatment and I-R renal injury were observed in terms of superoxide radical scavenging activity and histochemical features. Rats given dual treatment and I-R renal injury showed significant decreases in blood urea nitrogen. Increased expression of several inflammatory cytokines (tumor necrosis factor-α, interleukin-6, intracellular adhesion molecule-1, nuclear factor-κB, hypoxia inducible factor-1α, and heme oxygenase-1) was attenuated by the dual treatment. Dual gas inhalation decreases oxidative stress and markedly improves I-R-induced renal injury. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Therapeutic hypothermia reduces intestinal ischemia/reperfusion ...

    The detached intestinal epithelial cells in hypothermia group showed ... of apoptosis than those in normothermia group at 4 h (17.30 ± 2.56 vs. ... intestinal ischemia/reperfusion (IR) injury, which could be attenuated by therapeutic hypothermia.

  10. Radiographic manifestations of reperfusion edema after transplantation

    Park, Se Young; Kim, Tae Hoon; Ryu, Young Hoon; Moon, Sung Wook; Kim, Hyung Joong; Ahn, Chul Min; Paik, Hyo Chae; Lee, Doo Yun; Kim, Sang Jin

    2003-01-01

    To elucidate the sequential radiologic manifestations of reperfusion edema after lung transplantation. The study group comprised five consecutive lung transplant recipients (M:F=3:2;mean age; 47.5 years) who between July 1996 and April 2002 underwent lung transplantation procedures (four, unilateral; one, bilateral) at our institution. We retrospectively reviewed the serial postoperative radiographs obtained and characterized the lung infiltrates. Lung infiltrates compatible with reperfusion edema were present in all patients (5/5). Reperfusion edema appeared on day 1 in four, and by day 2 in the other. In all transplanted lungs, infiltrates were found in the perihilar and basilar regions, and were scored as maximal on day 1 in one, day 3 in two, day 4 in one and day 5 in the other. The recognition of sequential radiological manifestations helps identify recognition of reperfusion edema after lung transplantation

  11. Real-time digital imaging of leukocyte-endothelial interaction in ischemia-reperfusion injury (IRI) of the rat cremaster muscle.

    Thiele, Jan R; Goerendt, Kurt; Stark, G Bjoern; Eisenhardt, Steffen U

    2012-08-05

    Ischemia-reperfusion injury (IRI) has been implicated in a large array of pathological conditions such as cerebral stroke, myocardial infarction, intestinal ischemia as well as following transplant and cardiovascular surgery. Reperfusion of previously ischemic tissue, while essential for the prevention of irreversible tissue injury, elicits excessive inflammation of the affected tissue. Adjacent to the production of reactive oxygen species, activation of the complement system and increased microvascular permeability, the activation of leukocytes is one of the principle actors in the pathological cascade of inflammatory tissue damage during reperfusion. Leukocyte activation is a multistep process consisting of rolling, firm adhesion and transmigration and is mediated by a complex interaction between adhesion molecules in response to chemoattractants such as complement factors, chemokines, or platelet-activating factor. While leukocyte rolling in postcapillary venules is predominantly mediated by the interaction of selectins with their counter ligands, firm adhesion of leukocytes to the endothelium is selectin-controlled via binding to intercellular adhesion molecules (ICAM) and vascular cellular adhesion molecules (VCAM). Gold standard for the in vivo observation of leukocyte-endothelial interaction is the technique of intravital microscopy, first described in 1968. Though various models of IRI (ischemia-reperfusion injury) have been described for various organs, only few are suitable for direct visualization of leukocyte recruitment in the microvascular bed on a high level of image quality. We here promote the digital intravital epifluorescence microscopy of the postcapillary venule in the cremasteric microcirculation of the rat as a convenient method to qualitatively and quantitatively analyze leukocyte recruitment for IRI-research in striated muscle tissue and provide a detailed manual for accomplishing the technique. We further illustrate common pitfalls and

  12. Reperfusion hemorrhage following superior mesenteric artery stenting.

    Moore, Michael

    2012-02-03

    Percutaneous transluminal angioplasty and stent placement is now an established treatment option for chronic mesenteric ischemia and is associated with low mortality and morbidity rates. We present a case of reperfusion hemorrhage complicating endovascular repair of superior mesenteric artery stenosis. Although a recognized complication following repair of carotid stenosis, hemorrhage has not previously been reported following mesenteric endovascular reperfusion. We describe both spontaneous cessation of bleeding and treatment with coil embolization.

  13. Mitochondrial Bioenergetics During Ischemia and Reperfusion.

    Consolini, Alicia E; Ragone, María I; Bonazzola, Patricia; Colareda, Germán A

    2017-01-01

    During ischemia and reperfusion (I/R) mitochondria suffer a deficiency to supply the cardiomyocyte with chemical energy, but also contribute to the cytosolic ionic alterations especially of Ca 2+ . Their free calcium concentration ([Ca 2+ ]m) mainly depends on mitochondrial entrance through the uniporter (UCam) and extrusion in exchange with Na + (mNCX) driven by the electrochemical gradient (ΔΨm). Cardiac energetic is frequently estimated by the oxygen consumption, which determines metabolism coupled to ATP production and to the maintaining of ΔΨm. Nevertheless, a better estimation of heart energy consumption is the total heat release associated to ATP hydrolysis, metabolism, and binding reactions, which is measurable either in the presence or the absence of oxygenation or perfusion. Consequently, a mechano-calorimetrical approach on isolated hearts gives a tool to evaluate muscle economy. The mitochondrial role during I/R depends on the injury degree. We investigated the role of the mitochondrial Ca 2+ transporters in the energetic of hearts stunned by a model of no-flow I/R in rat hearts. This chapter explores an integrated view of previous and new results which give evidences to the mitochondrial role in cardiac stunning by ischemia o hypoxia, and the influence of thyroid alterations and cardioprotective strategies, such as cardioplegic solutions (high K-low Ca, pyruvate) and the phytoestrogen genistein in both sex. Rat ventricles were perfused in a flow-calorimeter at either 30 °C or 37 °C to continuously measure the left ventricular pressure (LVP) and total heat rate (Ht). A pharmacological treatment was done before exposing to no-flow I and R. The post-ischemic contractile (PICR as %) and energetical (Ht) recovery and muscle economy (Eco: P/Ht) were determined during stunning. The functional interaction between mitochondria (Mit) and sarcoplasmic reticulum (SR) was evaluated with selective mitochondrial inhibitors in hearts reperfused with Krebs-10 m

  14. Mitochondrial events responsible for morphine's cardioprotection against ischemia/reperfusion injury

    He, Haiyan; Huh, Jin; Wang, Huihua; Kang, Yi; Lou, Jianshi; Xu, Zhelong

    2016-01-01

    Morphine may induce cardioprotection by targeting mitochondria, but little is known about the exact mitochondrial events that mediate morphine's protection. We aimed to address the role of the mitochondrial Src tyrosine kinase in morphine's protection. Isolated rat hearts were subjected to 30 min ischemia and 2 h of reperfusion. Morphine was given before the onset of ischemia. Infarct size and troponin I release were measured to evaluate cardiac injury. Oxidative stress was evaluated by measuring mitochondrial protein carbonylation and mitochondrial ROS generation. HL-1 cells were subjected to simulated ischemia/reperfusion and LDH release and mitochondrial membrane potential (ΔΨm) were measured. Morphine reduced infarct size as well as cardiac troponin I release which were aborted by the selective Src tyrosine kinase inhibitors PP2 and Src-I1. Morphine also attenuated LDH release and prevented a loss of ΔΨm at reperfusion in a Src tyrosine kinase dependent manner in HL-1 cells. However, morphine failed to reduce LDH release in HL-1 cells transfected with Src siRNA. Morphine increased mitochondrial Src phosphorylation at reperfusion and this was abrogated by PP2. Morphine attenuated mitochondrial protein carbonylation and mitochondrial superoxide generation at reperfusion through Src tyrosine kinase. The inhibitory effect of morphine on the mitochondrial complex I activity was reversed by PP2. These data suggest that morphine induces cardioprotection by preventing mitochondrial oxidative stress through mitochondrial Src tyrosine kinase. Inhibition of mitochondrial complex I at reperfusion by Src tyrosine kinase may account for the prevention of mitochondrial oxidative stress by morphine. - Highlights: • Morphine induced mito-Src phosphorylation and reduced infarct size in rat hearts. • Morphine failed to reduce I/R-induced LDH release in Src-silencing HL-1 cells. • Morphine prevented mitochondria damage caused by I/R through Src. • Morphine reduced

  15. Mitochondrial events responsible for morphine's cardioprotection against ischemia/reperfusion injury

    He, Haiyan [Department of Physiology & Pathophysiology, Tianjin Medical University, Tianjin 300070 (China); Department of Pharmacology, Tianjin Medical University, Tianjin 300070 (China); Huh, Jin [Department of Anesthesia and Pain Medicine, Medical College, Kangwon National University, Chuncheon City (Korea, Republic of); Wang, Huihua [Department of Anesthesiology, The Second Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang Province (China); Kang, Yi; Lou, Jianshi [Department of Pharmacology, Tianjin Medical University, Tianjin 300070 (China); Xu, Zhelong, E-mail: zxu@tmu.edu.cn [Department of Physiology & Pathophysiology, Tianjin Medical University, Tianjin 300070 (China)

    2016-01-01

    Morphine may induce cardioprotection by targeting mitochondria, but little is known about the exact mitochondrial events that mediate morphine's protection. We aimed to address the role of the mitochondrial Src tyrosine kinase in morphine's protection. Isolated rat hearts were subjected to 30 min ischemia and 2 h of reperfusion. Morphine was given before the onset of ischemia. Infarct size and troponin I release were measured to evaluate cardiac injury. Oxidative stress was evaluated by measuring mitochondrial protein carbonylation and mitochondrial ROS generation. HL-1 cells were subjected to simulated ischemia/reperfusion and LDH release and mitochondrial membrane potential (ΔΨm) were measured. Morphine reduced infarct size as well as cardiac troponin I release which were aborted by the selective Src tyrosine kinase inhibitors PP2 and Src-I1. Morphine also attenuated LDH release and prevented a loss of ΔΨm at reperfusion in a Src tyrosine kinase dependent manner in HL-1 cells. However, morphine failed to reduce LDH release in HL-1 cells transfected with Src siRNA. Morphine increased mitochondrial Src phosphorylation at reperfusion and this was abrogated by PP2. Morphine attenuated mitochondrial protein carbonylation and mitochondrial superoxide generation at reperfusion through Src tyrosine kinase. The inhibitory effect of morphine on the mitochondrial complex I activity was reversed by PP2. These data suggest that morphine induces cardioprotection by preventing mitochondrial oxidative stress through mitochondrial Src tyrosine kinase. Inhibition of mitochondrial complex I at reperfusion by Src tyrosine kinase may account for the prevention of mitochondrial oxidative stress by morphine. - Highlights: • Morphine induced mito-Src phosphorylation and reduced infarct size in rat hearts. • Morphine failed to reduce I/R-induced LDH release in Src-silencing HL-1 cells. • Morphine prevented mitochondria damage caused by I/R through Src. • Morphine

  16. Protective effects of Tribulus terrestris L extract against acute kidney injury induced by reperfusion injury in rats.

    Najafi, Houshang; Firouzifar, Mohammad Reza; Shafaat, Omid; Changizi Ashtiyani, Saeed; Hosseini, Nasser

    2014-07-01

    This study aimed to investigate the protective effect of aerial parts of the Tribulus terrestris L extract on acute kidney injury (AKI) induced by ischemia for 30 minutes and reperfusion for 24 hours in rats. Ten male Sprague-Dawley rats in the AKI and 10 in the Tribulus terrestris groups received the extract solvent and extract of the plant (11 mg/kg), respectively, for 13 days (oral administration). On day 14, ischemia for 30 minutes and reperfusion for 24 hours were induced on the rats. In the last 6 hours of the reperfusion period (24 hours), urine samples were collected in metabolic cages. At the end of this period, blood samples were also taken to determine plasma urea nitrogen, creatinine, and electrolyte concentrations. The kidney tissues were collected for measuring the level of oxidative stress and histological studies. They were compared with the sham operation group and a control group with normal diet and no operation. In the Tribulus terrestris group, the increase in plasma creatinine and urea nitrogen concentrations was significantly less following reperfusion, and their values reached the same level as that in the sham group. Creatinine clearance and urine osmolarity in the Tribulus terrestris group was higher in comparison with the AKI group, whereas sodium absolute excretion, fractional excretion of potassium, oxidative stress, and cellular damages were less. Oral administration of Tribulus terrestris extract for 2 weeks can decrease kidney functional disturbance, oxidative stress, and cellular damages following reperfusion injury in rats.

  17. Research progress of traditional Chinese medicine extract for retinal ischemia-reperfusion injury

    Qian-Yu Jia

    2015-05-01

    Full Text Available Retinal ischemia-reperfusion injury(RIRIis a common clinical disease, and the producing mechanism is still in research. Experimental and clinical research in recent years have showed that the mechanism of RIRI and oxygen free radicals, gene regulation, calcium overload, inflammatory cytokines and other factors are closely related. In this article, we summarized the current situation that the scholars at home and abroad study traditional Chinese medicine extract of prevention and treatment of RIRI.

  18. Pharmacological activation of mitochondrial BKCa channels protects isolated cardiomyocytes against simulated reperfusion-induced injury

    Borchert, Gudrun H.; Hlaváčková, Markéta; Kolář, František

    2013-01-01

    Roč. 238, č. 2 (2013), s. 233-241 ISSN 1535-3702 R&D Projects: GA AV ČR(CZ) IAA500110804; GA ČR(CZ) GAP303/12/1162 Institutional research plan: CEZ:AV0Z50110509 Institutional support: RVO:67985823 Keywords : potassium channels * cardiomyocytes * mitochondria * ischemia/reperfusion * cytoprotection * reactive oxygen species Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 2.226, year: 2013

  19. Protective effects of dexrazoxane against acute ischaemia/reperfusion injury of rat hearts

    Neckář, Jan; Boudíková, Adéla; Mandíková, Petra; Štěrba, M.; Popelová, O.; Mikšík, Ivan; Dabrowská, L.; Mráz, J.; Geršl, V.; Kolář, František

    2012-01-01

    Roč. 90, č. 9 (2012), s. 1303-1310 ISSN 0008-4212 R&D Projects: GA AV ČR(CZ) IAAX01110901; GA ČR(CZ) GA305/09/0416 Institutional research plan: CEZ:AV0Z50110509 Keywords : heart * dexrazoxane * ischaemia * reperfusion * infarct size * arrhythmias * cardioprotection * reactive oxygen species Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 1.556, year: 2012

  20. The Use of an Acellular Oxygen Carrier in a Human Liver Model of Normothermic Machine Perfusion.

    Laing, Richard W; Bhogal, Ricky H; Wallace, Lorraine; Boteon, Yuri; Neil, Desley A H; Smith, Amanda; Stephenson, Barney T F; Schlegel, Andrea; Hübscher, Stefan G; Mirza, Darius F; Afford, Simon C; Mergental, Hynek

    2017-11-01

    Normothermic machine perfusion of the liver (NMP-L) is a novel technique that preserves liver grafts under near-physiological conditions while maintaining their normal metabolic activity. This process requires an adequate oxygen supply, typically delivered by packed red blood cells (RBC). We present the first experience using an acellular hemoglobin-based oxygen carrier (HBOC) Hemopure in a human model of NMP-L. Five discarded high-risk human livers were perfused with HBOC-based perfusion fluid and matched to 5 RBC-perfused livers. Perfusion parameters, oxygen extraction, metabolic activity, and histological features were compared during 6 hours of NMP-L. The cytotoxicity of Hemopure was also tested on human hepatic primary cell line cultures using an in vitro model of ischemia reperfusion injury. The vascular flow parameters and the perfusate lactate clearance were similar in both groups. The HBOC-perfused livers extracted more oxygen than those perfused with RBCs (O2 extraction ratio 13.75 vs 9.43 % ×10 per gram of tissue, P = 0.001). In vitro exposure to Hemopure did not alter intracellular levels of reactive oxygen species, and there was no increase in apoptosis or necrosis observed in any of the tested cell lines. Histological findings were comparable between groups. There was no evidence of histological damage caused by Hemopure. Hemopure can be used as an alternative oxygen carrier to packed red cells in NMP-L perfusion fluid.

  1. Tobacco Smoke: Involvement of Reactive Oxygen Species and Stable Free Radicals in Mechanisms of Oxidative Damage, Carcinogenesis and Synergistic Effects with Other Respirable Particles

    Konstantinos Fiotakis

    2009-02-01

    Full Text Available Tobacco smoke contains many toxic, carcinogenic and mutagenic chemicals, as well as stable and unstable free radicals and reactive oxygen species (ROS in the particulate and the gas phase with the potential for biological oxidative damage. Epidemiological evidence established that smoking is one of the most important extrinsic factor of premature morbidity and mortality. The objective of this study was to investigate oxidative and carcinogenic mechanisms of tobacco and synergistic action with other respirable particles in the respiratory system of smokers. Electron Paramagnetic Resonance (EPR and spin- trapping techniques were used to study stable free radicals in the cigarette tar, and unstable superoxide anion (O2·- and hydroxyl (HO· radicals in the smoke Results showed that the semiquinone radical system has the potential for redox recycling and oxidative action. Further, results proved that aqueous cigarette tar (ACT solutions can generate adducts with DNA nucleobases, particularly the mutagenic 8-hydroxy-2’-deoxyguanosine (a biomarker for carcinogenesis.Also, we observed synergistic effects in the generation of HO·, through the Fenton reaction, with environmental respirable particles (asbestos fibres, coal dust, etc. and ambient particulate matter (PM, such as PM10, PM2.5 and diesel exhaust particles (DEP. The highest synergistic effects was observed with the asbestos fibres (freshly grounded, PM2.5 and DEP. Finally, we discuss results from our previous study of conventional cellulose acetate filters and “bio-filters” with hemoglobin impregnated activated carbon, which showed that these filters do not substantially alter the free radical content of smoke in the particulate and in the gaseous phase.

  2. Tobacco Smoke: Involvement of Reactive Oxygen Species and Stable Free Radicals in Mechanisms of Oxidative Damage, Carcinogenesis and Synergistic Effects with Other Respirable Particles

    Valavanidis, Athanasios; Vlachogianni, Thomais; Fiotakis, Konstantinos

    2009-01-01

    Tobacco smoke contains many toxic, carcinogenic and mutagenic chemicals, as well as stable and unstable free radicals and reactive oxygen species (ROS) in the particulate and the gas phase with the potential for biological oxidative damage. Epidemiological evidence established that smoking is one of the most important extrinsic factor of premature morbidity and mortality. The objective of this study was to investigate oxidative and carcinogenic mechanisms of tobacco and synergistic action with other respirable particles in the respiratory system of smokers. Electron Paramagnetic Resonance (EPR) and spin-trapping techniques were used to study stable free radicals in the cigarette tar, and unstable superoxide anion (O2•−) and hydroxyl (HO•) radicals in the smoke Results showed that the semiquinone radical system has the potential for redox recycling and oxidative action. Further, results proved that aqueous cigarette tar (ACT) solutions can generate adducts with DNA nucleobases, particularly the mutagenic 8-hydroxy-2’-deoxyguanosine (a biomarker for carcinogenesis). Also, we observed synergistic effects in the generation of HO•, through the Fenton reaction, with environmental respirable particles (asbestos fibres, coal dust, etc.) and ambient particulate matter (PM), such as PM10, PM2.5 and diesel exhaust particles (DEP). The highest synergistic effects was observed with the asbestos fibres (freshly grounded), PM2.5 and DEP. Finally, we discuss results from our previous study of conventional cellulose acetate filters and “bio-filters” with hemoglobin impregnated activated carbon, which showed that these filters do not substantially alter the free radical content of smoke in the particulate and in the gaseous phase. PMID:19440393

  3. The effect of tobacco smoke exposure on the generation of reactive oxygen species and cellular membrane damage using co-culture model of blood brain barrier with astrocytes.

    Seo, Seung-Beom; Choe, Eun Sang; Kim, Kwang-Sik; Shim, Soon-Mi

    2017-06-01

    Brain tissue is known to be vulnerable to the exposure by tobacco smoke. Tobacco smoke can induce generation of reactive oxygen species (ROS), causing inflammatory activity and blood-brain barrier (BBB) impairment. The aim of the present study was to investigate the effect of tobacco smoke on cell cytotoxicity, generation of ROS, and cellular membrane damage in astrocytes and BBB using a co-culture system. Cell viability of U373MG cells was reduced in a dose-dependent manner, ranging from 96.7% to 40.3% by tobacco smoke condensate (TSC). Cell viability of U373MG co-cultured with human brain microvascular endothelial cells (HBMECs) was 104.9% at the IC 50 value of TSC. Trans-epithelial electric resistance values drastically decreased 80% following 12-h incubation. The value was maintained until 48 h and then increased at 72-h incubation (85%). It then decreased to 75% at 120 h. Generation of ROS increased in a dose-dependent manner, ranging from 102.7% to 107.9%, when various concentrations of TSC (4-16 mg/mL) were administered to the U373MG monoculture. When TSC was added into U373MG co-cultured with HBMECs, production of ROS ranged from 101.7% to 102.6%, slightly increasing over 12 h. Maximum exposure-generated ROS of 104.8% was reached at 24 h. Cell cytotoxicity and oxidative stress levels in the U373MG co-culture model system with HBMECs were lower than U373MG monoculture. HBMECs effectively acted as a barrier to protect the astrocytes (U373MG) from toxicity of TSC.

  4. Effect of hyperbaric oxygenation on mitochondrial function of neuronal cells in the cortex of neonatal rats after hypoxic-ischemic brain damage

    L. Yang

    2016-01-01

    Full Text Available The timing and mechanisms of protection by hyperbaric oxygenation (HBO in hypoxic-ischemic brain damage (HIBD have only been partially elucidated. We monitored the effect of HBO on the mitochondrial function of neuronal cells in the cerebral cortex of neonatal rats after HIBD. Neonatal Sprague-Dawley rats (total of 360 of both genders were randomly divided into normal control, HIBD, and HIBD+HBO groups. The HBO treatment began immediately after hypoxia-ischemia (HI and continued once a day for 7 consecutive days. Animals were euthanized 0, 2, 4, 6, and 12 h post-HI to monitor the changes in mitochondrial membrane potential (ΔΨm occurring soon after a single dose of HBO treatment, as well as 2, 3, 4, 5, 6, and 7 days post-HI to study ΔΨm changes after a series of HBO treatments. Fluctuations in ΔΨm were observed in the ipsilateral cortex in both HIBD and HIBD+HBO groups. Within 2 to 12 h after HI insult, the ΔΨm of the HIBD and HIBD+HBO groups recovered to some extent. A secondary drop in ΔΨm was observed in both groups during the 1-4 days post-HI period, but was more severe in the HIBD+HBO group. There was a secondary recovery of ΔΨm observed in the HIBD+HBO group, but not in the HIBD group, during the 5-7 days period after HI insult. HBO therapy may not lead to improvement of neural cell mitochondrial function in the cerebral cortex in the early stage post-HI, but may improve it in the sub-acute stage post-HI.

  5. Therapeutic metabolic inhibition: hydrogen sulfide significantly mitigates skeletal muscle ischemia reperfusion injury in vitro and in vivo

    Henderson, Peter W.; Singh, Sunil P.; Weinstein, Andrew L.; Nagineni, Vijay; Rafii, Daniel C.; Kadouch, Daniel; Krijgh, David D.; Spector, Jason A.

    2010-01-01

    BACKGROUND:: Recent evidence suggests that hydrogen sulfide is capable of mitigating the degree of cellular damage associated with ischemia-reperfusion injury. The purpose of this study was to determine whether it is protective in skeletal muscle. METHODS:: This study used both in vitro (cultured

  6. Effectiveness of sugammadex for cerebral ischemia/reperfusion injury.

    Ozbilgin, Sule; Yılmaz, Osman; Ergur, Bekir Ugur; Hancı, Volkan; Ozbal, Seda; Yurtlu, Serhan; Gunenc, Sakize Ferim; Kuvaki, Bahar; Kucuk, Burcu Ataseven; Sisman, Ali Rıza

    2016-06-01

    Cerebral ischemia may cause permanent brain damage and behavioral dysfunction. The efficacy and mechanisms of pharmacological treatments administered immediately after cerebral damage are not fully known. Sugammadex is a licensed medication. As other cyclodextrins have not passed the necessary phase tests, trade preparations are not available, whereas sugammadex is frequently used in clinical anesthetic practice. Previous studies have not clearly described the effects of the cyclodextrin family on cerebral ischemia/reperfusion (I/R) damage. The aim of this study was to determine whether sugammadex had a neuroprotective effect against transient global cerebral ischemia. Animals were assigned to control, sham-operated, S 16 and S 100 groups. Transient global cerebral ischemia was induced by 10-minute occlusion of the bilateral common carotid artery, followed by 24-hour reperfusion. At the end of the experiment, neurological behavior scoring was performed on the rats, followed by evaluation of histomorphological and biochemical measurements. Sugammadex 16 mg/kg and 100 mg/kg improved neurological outcome, which was associated with reductions in both histological and neurological scores. The hippocampus TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) and caspase results in the S 16 and S 100 treatment groups were significantly lower than those of the I/R group. Neurological scores in the treated groups were significantly higher than those of the I/R group. The study showed that treatment with 16 mg/kg and 100 mg/kg sugammadex had a neuroprotective effect in a transient global cerebral I/R rat model. However, 100 mg/kg sugammadex was more neuroprotective in rats. Copyright © 2016. Published by Elsevier Taiwan.

  7. Effectiveness of sugammadex for cerebral ischemia/reperfusion injury

    Sule Ozbilgin

    2016-06-01

    Full Text Available Cerebral ischemia may cause permanent brain damage and behavioral dysfunction. The efficacy and mechanisms of pharmacological treatments administered immediately after cerebral damage are not fully known. Sugammadex is a licensed medication. As other cyclodextrins have not passed the necessary phase tests, trade preparations are not available, whereas sugammadex is frequently used in clinical anesthetic practice. Previous studies have not clearly described the effects of the cyclodextrin family on cerebral ischemia/reperfusion (I/R damage. The aim of this study was to determine whether sugammadex had a neuroprotective effect against transient global cerebral ischemia. Animals were assigned to control, sham-operated, S 16 and S 100 groups. Transient global cerebral ischemia was induced by 10-minute occlusion of the bilateral common carotid artery, followed by 24-hour reperfusion. At the end of the experiment, neurological behavior scoring was performed on the rats, followed by evaluation of histomorphological and biochemical measurements. Sugammadex 16 mg/kg and 100 mg/kg improved neurological outcome, which was associated with reductions in both histological and neurological scores. The hippocampus TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling and caspase results in the S 16 and S 100 treatment groups were significantly lower than those of the I/R group. Neurological scores in the treated groups were significantly higher than those of the I/R group. The study showed that treatment with 16 mg/kg and 100 mg/kg sugammadex had a neuroprotective effect in a transient global cerebral I/R rat model. However, 100 mg/kg sugammadex was more neuroprotective in rats.

  8. The cardioprotective efficacy of TVP1022 in a rat model of ischaemia/reperfusion.

    Ertracht, Offir; Liani, Esti; Bachner-Hinenzon, Noa; Bar-Am, Orit; Frolov, Luba; Ovcharenko, Elena; Awad, Huda; Blum, Shany; Barac, Yaron; Amit, Tamar; Adam, Dan; Youdim, Moussa; Binah, Ofer

    2011-06-01

    Because myocardial infarction is a major cause of morbidity and mortality worldwide, protecting the heart from the ischaemia and reperfusion (I/R) damage is the focus of intense research. Based on our in vitro findings showing that TVP1022 (the S-enantiomer of rasagiline, an anti-Parkinsonian drug) possesses cardioprotective effects, in the present study we investigated the hypothesis that TVP1022 can attenuate myocardial damage in an I/R model in rats. The model consisted of 30-min occlusion of the left anterior descending artery followed by 4 or 24 h reperfusion. In addition, we investigated the possible mechanisms of cardioprotection in H9c2 cells and neonatal rat ventricular myocytes (NRVM) exposed to oxidative stress induced by H(2) O(2) . TVP1022 (20 and 40 mg·kg(-1) ) administered 5 min before reperfusion followed by an additional dose 4 h after reperfusion reduced the infarct size and attenuated the decline in ventricular function. TVP1022 also attenuated I/R-induced deterioration in cardiac mitochondrial integrity evaluated by mitochondrial swelling capacity. In vitro, using H9c2 cells and NRVM, TVP1022 attenuated both serum free- and H(2) O(2) -induced damage, preserved mitochondrial membrane potential and Bcl-2 levels, inhibited mitochondrial cytochrome c release and the increase in cleaved caspase 9 and 3 levels, and enhanced the phosphorylation of protein kinase C and glycogen synthase kinase-3β. TVP1022 provided cardioprotection in a model of myocardial infarction, and therefore should be considered as a novel adjunctive therapy for attenuating myocardial damage resulting from I/R injuries. © 2011 The Authors. British Journal of Pharmacology © 2011 The British Pharmacological Society.

  9. The effect of melatonin on bacterial translocation following ischemia/reperfusion injury in a rat model of superior mesenteric artery occlusion.

    Ozban, Murat; Aydin, Cagatay; Cevahir, Nural; Yenisey, Cigdem; Birsen, Onur; Gumrukcu, Gulistan; Aydin, Berrin; Berber, Ibrahim

    2015-03-08

    Acute mesenteric ischemia is a life-threatening vascular emergency resulting in tissue destruction due to ischemia-reperfusion injury. Melatonin, the primary hormone of the pineal gland, is a powerful scavenger of reactive oxygen species (ROS), including the hydroxyl and peroxyl radicals, as well as singlet oxygen, and nitric oxide. In this study, we aimed to investigate whether melatonin prevents harmful effects of superior mesenteric ischemia-reperfusion on intestinal tissues in rats. Rats were randomly divided into three groups, each having 10 animals. In group I, the superior mesenteric artery (SMA) was isolated but not occluded. In group II and group III, the SMA was occluded immediately distal to the aorta for 60 minutes. After that, the clamp was removed and the reperfusion period began. In group III, 30 minutes before the start of reperfusion, 10 mg/kg melatonin was administered intraperitonally. All animals were sacrified 24 hours after reperfusion. Tissue samples were collected to evaluate the I/R-induced intestinal injury and bacterial translocation (BT). There was a statistically significant increase in myeloperoxidase activity, malondialdehyde levels and in the incidence of bacterial translocation in group II, along with a decrease in glutathione levels. These investigated parameters were found to be normalized in melatonin treated animals (group III). We conclude that melatonin prevents bacterial translocation while precluding the harmful effects of ischemia/reperfusion injury on intestinal tissues in a rat model of superior mesenteric artery occlusion.

  10. Hemorheological changes in ischemia-reperfusion: an overview on our experimental surgical data.

    Nemeth, Norbert; Furka, Istvan; Miko, Iren

    2014-01-01

    Blood vessel occlusions of various origin, depending on the duration and extension, result in tissue damage, causing ischemic or ischemia-reperfusion injuries. Necessary surgical clamping of vessels in vascular-, gastrointestinal or parenchymal organ surgery, flap preparation-transplantation in reconstructive surgery, as well as traumatological vascular occlusions, all present special aspects. Ischemia and reperfusion have effects on hemorheological state by numerous ways: besides the local metabolic and micro-environmental changes, by hemodynamic alterations, free-radical and inflammatory pathways, acute phase reactions and coagulation changes. These processes may be harmful for red blood cells, impairing their deformability and influencing their aggregation behavior. However, there are still many unsolved or non-completely answered questions on relation of hemorheology and ischemia-reperfusion. How do various organ (liver, kidney, small intestine) or limb ischemic-reperfusionic processes of different duration and temperature affect the hemorheological factors? What is the expected magnitude and dynamics of these alterations? Where is the border of irreversibility? How can hemorheological investigations be applied to experimental models using laboratory animals in respect of inter-species differences? This paper gives a summary on some of our research data on organ/tissue ischemia-reperfusion, hemorheology and microcirculation, related to surgical research and experimental microsurgery.

  11. Isoprostanes--markers of ischaemia reperfusion injury.

    Sakamoto, H

    2012-02-03

    Ischaemia reperfusion injury is a common and important phenomenon that occurs predictably in patients undergoing such procedures as cardiopulmonary bypass, thrombolysis, surgery under tourniquet, organ transplantation or embolectomy. Oxidative stress and the resulting lipid peroxidation play a major role in reperfusion injury. Membrane and cellular dysfunction result and, subsequently, organ injury or failure may ensue. Traditional methods of quantifying ischaemia reperfusion injury, including measurement of malondialdehyde, lack specificity and sensitivity. It was reported in 1990 that isoprostanes, a series of prostaglandin-like compounds, are produced by the free radical-catalyzed peroxidation of arachidonic acid. Measurement of the isoprostane concentration in urine or plasma provides the most reliable, non-invasive method currently available to assess oxidative stress in vivo. Serial measurement of isoprostanes in biological fluids has enhanced our understanding of the mechanisms underlying ischaemia reperfusion injury itself and its role in certain diseases. Furthermore, measurement of the isoprostane concentration provides a means to assess the effects of prophylactic and therapeutic interventions. In the future, the development of rapid, simple assays for isoprostanes offers the potential to assess prognosis during and after ischaemia reperfusion events.

  12. Photoacoustic imaging for assessing ischemic kidney damage in vivo

    Berndl, Elizabeth S. L.; He, Xiaolin; Yuen, Darren A.; Kolios, Michael C.

    2018-02-01

    Ischemic reperfusion injuries (IRIs) occur after blood returns to a tissue or organ after a period without oxygen or nutrients, which causes an inflammatory response leading to heterogeneous scarring of the nearby tissue and vasculature. This is associated with long-term decreases blood flow, and necrosis. Although most commonly associated with heart attacks and strokes, IRIs are also a side effect of organ transplants, when the organ is reperfused in the recipient's body after being transported from the donor to the transplant hospital. Currently, the optimal method of monitoring for IRI is limited to biopsies, which are invasive and poorly monitor the spatial heterogeneity of the damage. To non-invasively identify changes in kidneys, the left renal artery in mice (n=3) was clamped for 45 minutes to create an IRI event. Both kidneys of each animal were monitored using photoacoustics (PA) with the VevoLAZR system (Fujifilm-VisualSonics, Toronto) three, four and eight weeks after surgery. IRI-treated kidneys show increased picosirius red staining, indicative of collagen (0.601 vs 0.042, p < 0.0001), decreased size as assessed by cross-sectional area (7.8 mm2 vs 35.9 mm2 , p < 0.0001), and decreased oxygen saturation (sO2; 62% vs 77%, p = 0.02). Analysis of the photoacoustic data shows that a two-point metric, the 715:930 nm ratio of the whole kidney (1.05 vs 0.57, p = 0.049) and the optical spectral slope (OSS) (0.8 * 10-3 vs 3.0 * 10-3, p = 0.013) are both able to differentiate between IRI-treated and healthy kidneys. These data suggest that photoacoustics can be used as a non-invasive method to observe in vivo changes in the kidney due to IRI.

  13. Breath pentane as a potential biomarker for survival in hepatic ischemia and reperfusion injury--a pilot study.

    Changsong Wang

    Full Text Available BACKGROUND: Exhaled pentane, which is produced as a consequence of reactive oxygen species-mediated lipid peroxidation, is a marker of oxidative stress. Propofol is widely used as a hypnotic agent in intensive care units and the operating room. Moreover, this agent has been reported to inhibit lipid peroxidation by directly scavenging reactive oxygen species. In this study, using a porcine liver ischemia-reperfusion injury model, we have evaluated the hypothesis that high concentrations of breath pentane are related to adverse outcome and that propofol could reduce breath pentane and improve liver injury and outcome in swine in this situation. METHODOLOGY/PRINCIPAL FINDINGS: Twenty male swine were assigned to two groups: propofol (n = 10 and chloral hydrate groups (n = 10. Hepatic ischemia was induced by occluding the portal inflow vessels. Ischemia lasted for 30 min, followed by reperfusion for 360 min. Exhaled and blood pentane concentrations in the chloral hydrate group markedly increased 1 min after reperfusion and then decreased to baseline. Breath and blood pentane concentrations in the propofol group increased 1 min after reperfusion but were significantly lower than in the chloral hydrate group. A negative correlation was found between breath pentane levels and survival in the chloral hydrate group. The median overall survival was 251 min after reperfusion (range 150-360 min in the chloral hydrate group. All of the swine were alive in the propofol group. CONCLUSIONS: Monitoring of exhaled pentane may be useful for evaluating the severity of hepatic ischemia-reperfusion injury and aid in predicting the outcome; propofol may improve the outcome in this situation.

  14. Combination Anti-Apoptotic Effect of Erythropoietin and Melatonin on Ischemia Reperfusion-Induced Renal Injury in Rats

    Shokofeh Banaei

    2016-11-01

    Full Text Available Renal ischemia-reperfusion (IR contributes to the development of acute renal failure (ARF. Oxygen free radicals are considered to be principal components involved in the pathophysiological tissue alterations observed during renal IR. The purpose of this study was to investigate the combination effect of melatonin (MEL and erythropoietin (EPO, which are a potent antioxidant and anti-apoptotic agents, in IR-induced renal injury in rats. Wistar Albino rats were unilaterally nephrectomized and subjected to 45 min of renal pedicle occlusion followed by 24 h reperfusion. MEL (10 mg/kg, i.p and EPO (5000 U/kg, i.p were administered prior to ischemia. After 24 h reperfusion, following decapitation, blood samples were collected for the determination of superoxide dismutase (SOD, glutathione peroxidase (GPx, and malondialdehyde (MDA levels. Also, renal samples were taken for histological evaluation and apoptosis assay. Ischemia-reperfusion increased SOD, GPx, MDA levels, and TUNEL positive cells. Histopathological findings of the IR group confirmed that there was renal impairment in the tubular epithelium. Treatment with EPO and MEL decreased SOD, GPx, and MDA levels, histopathological changes, and TUNEL positive cells. These results indicated that the combination of MEL and EPO could not exert more nephroprotective and anti-apoptotic effects than MEL treatment in renal ischemia-reperfusion injury.

  15. A vigilant, hypoxia-regulated heme oxygenase-1 gene vector in the heart limits cardiac injury after ischemia-reperfusion in vivo.

    Tang, Yao Liang; Qian, Keping; Zhang, Y Clare; Shen, Leping; Phillips, M Ian

    2005-12-01

    The effect of a cardiac specific, hypoxia-regulated, human heme oxygenase-1 (hHO-1) vector to provide cardioprotection from ischemia-reperfusion injury was assessed. When myocardial ischemia and reperfusion is asymptomatic, the damaging effects are cumulative and patients miss timely treatment. A gene therapy approach that expresses therapeutic genes only when ischemia is experienced is a desirable strategy. We have developed a cardiac-specific, hypoxia-regulated gene therapy "vigilant vector'' system that amplifies cardioprotective gene expression. Vigilant hHO-1 plasmids, LacZ plasmids, or saline (n = 40 per group) were injected into mouse heart 2 days in advance of ischemia-reperfusion injury. Animals were exposed to 60 minutes of ischemia followed by 24 hours of reperfusion. For that term (24 hours) effects, the protein levels of HO-1, inflammatory responses, apoptosis, and infarct size were determined. For long-term (3 week) effects, the left ventricular remodeling and recovery of cardiac function were assessed. Ischemia-reperfusion resulted in a timely overexpression of HO-1 protein. Infarct size at 24 hours after ischemia-reperfusion was significantly reduced in the HO-1-treated animals compared with the LacZ-treated group or saline-treated group (P < .001). The reduction of infarct size was accompanied by a decrease in lipid peroxidant activity, inflammatory cell infiltration, and proapoptotic protein level in ischemia-reperfusion-injured myocardium. The long-term study demonstrated that timely, hypoxia-induced HO-1 overexpression is beneficial in conserving cardiac function and attenuating left ventricle remodelling. The vigilant HO-1 vector provides a protective therapy in the heart for reducing cellular damage during ischemia-reperfusion injury and preserving heart function.

  16. NFAT5 is activated by hypoxia: role in ischemia and reperfusion in the rat kidney.

    Sandra Villanueva

    Full Text Available The current hypothesis postulates that NFAT5 activation in the kidney's inner medulla is due to hypertonicity, resulting in cell protection. Additionally, the renal medulla is hypoxic (10-18 mmHg; however there is no information about the effect of hypoxia on NFAT5. Using in vivo and in vitro models, we evaluated the effect of reducing the partial pressure of oxygen (PO(2 on NFAT5 activity. We found that 1 Anoxia increased NFAT5 expression and nuclear translocation in primary cultures of IMCD cells from rat kidney. 2 Anoxia increased transcriptional activity and nuclear translocation of NFAT5 in HEK293 cells. 3 The dose-response curve demonstrated that HIF-1α peaked at 2.5% and NFAT5 at 1% of O(2. 4 At 2.5% of O(2, the time-course curve of hypoxia demonstrated earlier induction of HIF-1α gene expression than NFAT5. 5 siRNA knockdown of NFAT5 increased the hypoxia-induced cell death. 6 siRNA knockdown of HIF-1α did not affect the NFAT5 induction by hypoxia. Additionally, HIF-1α was still induced by hypoxia even when NFAT5 was knocked down. 7 NFAT5 and HIF-1α expression were increased in kidney (cortex and medulla from rats subjected to an experimental model of ischemia and reperfusion (I/R. 7 Experimental I/R increased the NFAT5-target gene aldose reductase (AR. 8 NFAT5 activators (ATM and PI3K were induced in vitro (HEK293 cells and in vivo (I/R kidneys with the same timing of NFAT5. 8 Wortmannin, which inhibits ATM and PI3K, reduces hypoxia-induced NFAT5 transcriptional activation in HEK293 cells. These results demonstrate for the first time that NFAT5 is induced by hypoxia and could be a protective factor against ischemic damage.

  17. Oxidative stress in ischemia and reperfusion

    Sinning, Christoph; Westermann, Dirk; Clemmensen, Peter

    2017-01-01

    Oxidative stress remains a major contributor to myocardial injury after ischemia followed by reperfusion (I/R) as the reperfusion of the myocardial infarction (MI) area inevitably leads to a cascade of I/R injury. This review focused on concepts of the antioxidative defense system and elucidates......, the different mechanisms through which myocardial protection can be addressed, like ischemic postconditioning in myocardial infarction or adjunctive measures like targeted temperature management as well as new theories, including the role of iron in I/R injury, will be discussed....

  18. Effects of FK506 on Hippocampal CA1 Cells Following Transient Global Ischemia/Reperfusion in Wistar Rat

    Zahra-Nadia Sharifi

    2012-01-01

    Full Text Available Transient global cerebral ischemia causes loss of pyramidal cells in CA1 region of hippocampus. In this study, we investigated the neurotrophic effect of the immunosuppressant agent FK506 in rat after global cerebral ischemia. Both common carotid arteries were occluded for 20 minutes followed by reperfusion. In experimental group 1, FK506 (6 mg/kg was given as a single dose exactly at the time of reperfusion. In the second group, FK506 was administered at the beginning of reperfusion, followed by its administration intraperitoneally (IP 6, 24, 48, and 72 hours after reperfusion. FK506 failed to show neurotrophic effects on CA1 region when applied as a single dose of 6 mg/kg. The cell number and size of the CA1 pyramidal cells were increased, also the number of cell death decreased in this region when FK506 was administrated 48 h after reperfusion. This work supports the possible use of FK506 in treatment of ischemic brain damage.

  19. Adverse effects of reduced oxygen tension on the proliferative capacity of rat kidney and insulin-secreting cell lines involve DNA damage and stress responses

    Chen Jianhua; Jones, R. Huw; Tarry-Adkins, Jane; Smith, Noel H.; Ozanne, Susan E.

    2008-01-01

    Standard cell culture conditions do not reflect the physiological environment in terms of oxygen tension (20% vs 3%). The effects of lowering oxygen tension on cell proliferation in culture can be beneficial as well as detrimental depending on the cell line studied, but the molecular mechanism underlying such effects is not fully understood. We observed that the proliferative capacity of the rat cell lines NRK and INS-1 was inhibited when cultured under 3% oxygen as compared to 20% oxygen. Suppression of proliferation in NRK cells was accompanied by induction of DNA double strand breaks whereas in INS-1 cells it was accompanied by up-regulation of p53 and p27. Although Sirt1 was up-regulated in both cell lines by 3% oxygen the effects on antioxidant enzymes (MnSOD, CuZnSOD and catalase) were cell line specific. Marked up-regulation of heme oxygenase-1 (HO-1) was detected in both NRK and INS-1 cells when cultured in 3% oxygen. HO-1 expression can be readily induced by exposure to hydrogen peroxide in culture. These results suggest that reduced oxygen tension suppresses the proliferative capacity of these two cell lines through a stress response that is similar to an oxidative stress response but the molecular events that lead to the reduced cell proliferation are cell line specific

  20. The cardioprotective efficacy of TVP1022 against ischemia/reperfusion injury and cardiac remodeling in rats.

    Malka, Assaf; Ertracht, Offir; Bachner-Hinenzon, Noa; Reiter, Irina; Binah, Ofer

    2016-12-01

    Following acute myocardial infarction (MI), early and successful reperfusion is the most effective strategy for reducing infarct size and improving the clinical outcome. However, immediate restoration of blood flow to the ischemic zone results in myocardial damage, defined as "reperfusion-injury". Whereas we previously reported that TVP1022 (the S-isomer of rasagiline, FDA-approved anti-Parkinson drug) decreased infarct size 24 h post ischemia reperfusion (I/R) in rats, in this study we investigated the chronic cardioprotective efficacy of TVP1022 14 days post-I/R. To simulate the clinical settings of acute MI followed by reperfusion therapy, we employed a rat model of left anterior descending artery occlusion for 30 min followed by reperfusion and a follow-up for 14 days. TVP1022 was initially administered postocclusion-prereperfusion, followed by chronic daily administrations. Cardiac performance and remodeling were evaluated using customary and advanced echocardiographic methods, hemodynamic measurements by Millar Mikro-Tip ® catheter, and histopathological techniques. TVP1022 administration markedly decreased the remodeling process as illustrated by attenuation of left ventricular enlargement and cardiac hypertrophy (both at the whole heart and the cellular level). Furthermore, TVP1022 inhibited cardiac fibrosis and reduced ventricular BNP levels. Functionally, TVP1022 treatment preserved cardiac wall motion. Specifically, the echocardiographic and most of the direct hemodynamic measures were pronouncedly improved by TVP1022. Collectively, these findings indicate that TVP1022 provides prominent cardioprotection against I/R injury and post-MI remodeling in this I/R model.

  1. Protective effect of preconditioning and adenosine pretreatment in experimental skeletal muscle reperfusion injury.

    Papanastasiou, S; Estdale, S E; Homer-Vanniasinkam, S; Mathie, R T

    1999-07-01

    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.

  2. Impairment of endothelial-myocardial interaction increases the susceptibility of cardiomyocytes to ischemia/reperfusion injury.

    Thorsten M Leucker

    Full Text Available Endothelial-myocardial interactions may be critically important for ischemia/reperfusion injury. Tetrahydrobiopterin (BH4 is a required cofactor for nitric oxide (NO production by endothelial NO synthase (eNOS. Hyperglycemia (HG leads to significant increases in oxidative stress, oxidizing BH4 to enzymatically incompetent dihydrobiopterin. How alterations in endothelial BH4 content impact myocardial ischemia/reperfusion injury remains elusive. The aim of this study was to examine the effect of endothelial-myocardial interaction on ischemia/reperfusion injury, with an emphasis on the role of endothelial BH4 content. Langendorff-perfused mouse hearts were treated by triton X-100 to produce endothelial dysfunction and subsequently subjected to 30 min of ischemia followed by 2 h of reperfusion. The recovery of left ventricular systolic and diastolic function during reperfusion was impaired in triton X-100 treated hearts compared with vehicle-treated hearts. Cardiomyocytes (CMs were co-cultured with endothelial cells (ECs and subsequently subjected to 2 h of hypoxia followed by 2 h of reoxygenation. Addition of ECs to CMs at a ratio of 1∶3 significantly increased NO production and decreased lactate dehydrogenase activity compared with CMs alone. This EC-derived protection was abolished by HG. The addition of 100 µM sepiapterin (a BH4 precursor or overexpression of GTP cyclohydrolase 1 (the rate-limiting enzyme for BH4 biosynthesis in ECs by gene trasfer enhanced endothelial BH4 levels, the ratio of eNOS dimer/monomer, eNOS phosphorylation, and NO production and decreased lactate dehydrogenase activity in the presence of HG. These results demonstrate that increased BH4 content in ECs by either pharmacological or genetic approaches reduces myocardial damage during hypoxia/reoxygenation in the presence of HG. Maintaining sufficient endothelial BH4 is crucial for cardioprotection against hypoxia/reoxygenation injury.

  3. Carbamazepine suppresses calpain-mediated autophagy impairment after ischemia/reperfusion in mouse livers

    Kim, Jae-Sung, E-mail: Jae.Kim@surgery.ufl.edu; Wang, Jin-Hee, E-mail: jin-hee.wang@surgery.ufl.edu; Biel, Thomas G., E-mail: Thomas.Biel@surgery.ufl.edu; Kim, Do-Sung, E-mail: do-sung.kim@surgery.med.ufl.edu; Flores-Toro, Joseph A., E-mail: Joseph.Flores-Toro@surgery.ufl.edu; Vijayvargiya, Richa, E-mail: rvijayvargiya@ufl.edu; Zendejas, Ivan, E-mail: ivan.zendejas@surgery.ufl.edu; Behrns, Kevin E., E-mail: Kevin.Behrns@surgery.ufl.edu

    2013-12-15

    Onset of the mitochondrial permeability transition (MPT) plays a causative role in ischemia/reperfusion (I/R) injury. Current therapeutic strategies for reducing reperfusion injury remain disappointing. Autophagy is a lysosome-mediated, catabolic process that timely eliminates abnormal or damaged cellular constituents and organelles such as dysfunctional mitochondria. I/R induces calcium overloading and calpain activation, leading to degradation of key autophagy-related proteins (Atg). Carbamazepine (CBZ), an FDA-approved anticonvulsant drug, has recently been reported to increase autophagy. We investigated the effects of CBZ on hepatic I/R injury. Hepatocytes and livers from male C57BL/6 mice were subjected to simulated in vitro, as well as in vivo I/R, respectively. Cell death, intracellular calcium, calpain activity, changes in autophagy-related proteins (Atg), autophagic flux, MPT and mitochondrial membrane potential after I/R were analyzed in the presence and absence of 20 μM CBZ. CBZ significantly increased hepatocyte viability after reperfusion. Confocal microscopy revealed that CBZ prevented calcium overloading, the onset of the MPT and mitochondrial depolarization. Immunoblotting and fluorometric analysis showed that CBZ blocked calpain activation, depletion of Atg7 and Beclin-1 and loss of autophagic flux after reperfusion. Intravital multiphoton imaging of anesthetized mice demonstrated that CBZ substantially reversed autophagic defects and mitochondrial dysfunction after I/R in vivo. In conclusion, CBZ prevents calcium overloading and calpain activation, which, in turn, suppresses Atg7 and Beclin-1 depletion, defective autophagy, onset of the MPT and cell death after I/R. - Highlights: • A mechanism of carbamazepine (CBZ)-induced cytoprotection in livers is proposed. • Impaired autophagy is a key event contributing to lethal reperfusion injury. • The importance of autophagy is extended and confirmed in an in vivo model. • CBZ is a potential

  4. [Effects of flunarizine and vitamin C on hemodynamics in rat heart subjected to ischemia-reperfusion].

    Xian, Y; Lan, T; Wang, Y

    1998-09-01

    Langendorff perfusion isolated rat heart was subjected to total global ischemia (coronary flow rate is equal to zero) for 10 minutes and reperfusion for 15 minutes. The heart rate (HR), left ventricular developed pressure (LVDP), coronary flow rate (CFR), electrocardiogram (ECG) and the effects of calcium antagonist-flunarizine (FNZ) and/or oxygen free radical scavenger--vitamine C on the above parameters were observed. The results showed that FNZ dilated coronary vessel (P Vitamine C did not affect HR, LVP and CFR. The recovery of the product of HR and LVDP-Rate Pressure Product (RPP) in the FNZ + Vit. C group, Vit. C group and FNZ group was significantly higher than that in the control group (P C may improve the recovery of heart function after reperfusion.

  5. [Pulmonary reperfusion syndrome after pulmonary stent implants in a patient with vascular tortuosity syndrome].

    Berenguer Potenciano, M; Piris Borregas, S; Mendoza Soto, A; Velasco Bayon, J M; Caro Barri, A

    2015-01-01

    Vascular tortuosity syndrome is a rare genetic disorder that causes tortuosity and stenosis of the pulmonary, systemic and / or coronary circulations. As a result of treatment of pulmonary stenosis, symptoms of pulmonary edema, known as lung reperfusion syndrome, may occur. The case is presented of an adolescent patient with vascular tortuosity syndrome who presented with a pulmonary reperfusion syndrome after multiple stent implants in the left pulmonary artery. After the procedure, the patient immediately developed an acute pulmonary edema with severe clinical deterioration, which required assistance with extracorporeal membrane oxygenation for recovery. Copyright © 2014 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

  6. Sodium Hypochlorite-Modified Hemosorbents in the Treatment of Limb Ischemia-Reperfusion Syndrome: Experimental Study

    V. I. Sergiyenko

    2007-01-01

    Full Text Available Objective: to enhance the efficiency of treatment for limb ischemia-reperfusion syndrome in an experiment, by using the modified hemosorbents that have oxidative properties.Materials and methods. The investigation was conducted on 94 mongrel male dogs divided into 3 groups: 1 intact animals (n=20; 2 animals treated with hemocarboperfusion on the standard sorbent CKH-1K (n=36; 3 animals received hemocarboperfusion on sodium hypochloride-modified sorbent CKH-1K (n=38. A model of acute ischemia-reperfusion syndrome was created by the method of V. D. Pasechnikov et al. Partial oxygen tension (pO2 was determined by pin polarography. The levels of vasoactive eicosanoids were measured by enzyme immunoassay.Results. In the animals with leg ischemia syndrome, there is a significant pO2 reduction in the muscles of the hip and shin, which does not completely recover after reperfusion. Standard CKN-1K sorbent hemocarboperfusion reduces pO2 as compared with the reperfusion period while the use of modified CKH-1K hemosorbent increased pO2 in the study hind limb muscles to the level observed in intact animals. The development of ischemia and reperfusion is accompanied by the elevated levels of inflammatory mediators that have vasoconstrictive properties (thromboxane B2, endothelin-1, leukotrienes C4/D4/E4 and the lower concentration of the vasodilator prostacyclin. Standard CKN-1K sorbent hemocarboperfusion results in a further increase in the concentrations of thromboxane B2 and leukotrienes C4/D4/E4, a decrease in the concentration of endothelin-1, and an elevation of the levels of prostacyclin and prostaglandin E2. When sodium hypochlorite-modified CKN-1K sorbent hemocarboperfusion is employed, the concentrations of thromboxane B2, endothelin-1, and leukotrienes C4/D4/E4 decrease, and the level of prostacyclin increases.Conclusion. Hemocarboperfusion used in the treatment of leg ischemia-reperfusion syndrome leads to restoration of tissue oxygenation and

  7. Cordyceps sinensis protects against renal ischemia/reperfusion injury in rats.

    Wang, Hua-Pin; Liu, Ching-Wen; Chang, Hsueh-Wen; Tsai, Jen-Wei; Sung, Ya-Zhu; Chang, Li-Ching

    2013-03-01

    Cordyceps sinensis (CS) is an entomogenous fungus used as a tonic food and Chinese medicine to replenish health. This study investigated the protective effects of CS in rats post-renal ischemia-reperfusion (I/R) sequence by analyzing the influence on stromal cell-derived factor-1α (SDF-1α and chemokine (C-X-C motif) receptor 4 (CXCR4) expressions and senescence during recovery. Chemokine SDF-1 [now called chemokine C-X-C motif ligand 12 (CXCL12)] and its receptor CXCR4 are crucial in kidney repair after ischemic acute renal failure. CS treatment significantly alleviated I/R-induced renal damage assessed by creatinine levels (p < 0.05) and abated renal tubular damages assessed by periodic acid-Schiff with diastase (PASD) staining. CS induced early SDF-1α expression and increased CXCR4 expression 1-6 h post-reperfusion. Histology studies have revealed that CS induced SDF-1α in squamous cells of Bowman's capsule, mesangial cells, distal convoluted tubules (DCT), and proximal convoluted tubules (PCT). CS also improved renal repair in I/R-induced injury by increasing Ki-67 staining. I/R induced renal senescence after 3 and 6 h of reperfusion. However, CS alleviated I/R-induced senescence at early stage (1 and 3 h). We conclude that CS protects against I/R injury via the SDF-1/CXCR4-signaling axis and alleviates senescence.

  8. Protective Effect of Platelet Rich Plasma on Experimental Ischemia/Reperfusion Injury in Rat Ovary.

    Bakacak, Murat; Bostanci, Mehmet Suhha; İnanc, Fatma; Yaylali, Asli; Serin, Salih; Attar, Rukset; Yildirim, Gazi; Yildirim, Ozge Kizilkale

    2016-01-01

    Ovarian torsion is a common cause of local ischemic damage, reduced follicular activity and infertility. Platelet-rich plasma (PRP) contains growth factors with demonstrated cytoprotective properties; so we evaluated PRP efficacy in a rat ischemia/reperfusion (I/R) model. Sixty adult female Sprague-Dawley albino rats were randomly assigned to 6 groups of 8 animals each: Sham, Ischemia, I/R, Sham + PRP, I + PRP and I/R + PRP; and the remaining 12 used to prepare PRP. Ischemia groups were subjected to bilateral adnexal torsion for 3 h, while I/R and I/R + PRP groups received subsequent detorsion for 3 h. Intraperitoneal PRP was administered 30 min prior to ischemia (Ischemia + PRP) or reperfusion (I/R + PRP). Total oxidant status (TOS), oxidative stress index (OSI) and total ovarian histopathological scores were higher in Ischemia and I/R groups than in the Sham group (p OSI and histopathological scores in I + PRP and I/R + PRP groups compared to the corresponding Ischemia and I/R groups (p OSI (r = 0.877, p < 0.001). Peritoneal vascular endothelial growth factor was significantly higher in PRP-treated groups than corresponding untreated groups (p < 0.05). PRP is effective for the prevention of ischemia and reperfusion damage in rat ovary. © 2015 S. Karger AG, Basel.

  9. Neuroprotection of ebselen against ischemia/reperfusion injury involves GABA shunt enzymes.

    Seo, Jeong Yeol; Lee, Choong Hyun; Cho, Jun Hwi; Choi, Jung Hoon; Yoo, Ki-Yeon; Kim, Dae Won; Park, Ok Kyu; Li, Hua; Choi, Soo Young; Hwang, In Koo; Won, Moo-Ho

    2009-10-15

    Seleno-organic compound, ebselen (2-phenyl-1,2-benzisoselenazol-3(2H)-one), is a substrate with radical-scavenging activity. In this study, we observed the neuroprotective effects of ebselen against ischemic damage and on GABA shunt enzymes such as glutamic acid decarboxylase 67 (GAD67), GABA transaminse (GABA-T) and succinic semialdehyde dehydrogenase (SSADH) in the hippocampal CA1 region after 5 min of transient forebrain ischemia in gerbils. For this, vehicle (physiological saline) or ebselen was administered 30 min before or after ischemia/reperfusion and sacrificed 4 days after ischemia/reperfusion. The administration of ebselen significantly reduced the neuronal death in the CA1 region induced by ischemia/reperfusion. In addition, treatment with ebselen markedly elevated GAD67, GABA-T and SSADH immunoreactivity and their protein levels compared to that in the vehicle-treated group, respectively. These results suggest that ebselen protects neurons from ischemic damage via control of the expressions of GABA shunt enzymes to enter the TCA cycle.

  10. Colchicine protects rat skeletal muscle from ischemia/reperfusion injury by suppressing oxidative stress and inflammation

    Liangrong Wang

    2016-06-01

    Full Text Available Objective(s: Neutrophils play an important role in ischemia/reperfusion (IR induced skeletal muscle injury. Microtubules are required for neutrophil activation in response to various stimuli. This study aimed to investigate the effects of colchicine, a microtubule-disrupting agent, on skeletal muscle IR injury in a rat hindlimb ischemia model. Materials and Methods: Twenty-one Sprague-Dawley rats were randomly allocated into three groups: IR group, colchicine treated-IR (CO group and sham operation (SM group. Rats of both the IR and CO groups were subjected to 3 hr of ischemia by clamping the right femoral artery followed by 2 hr of reperfusion. Colchicine (1 mg/kg was administrated intraperitoneally prior to hindlimb ischemia in the CO group. After 2 hr of reperfusion, we measured superoxide dismutase (SOD and myeloperoxidase (MPO activities, and malondialdehyde (MDA, tumor necrosis factor (TNF-α and interleukin (IL-1β levels in the muscle samples. Plasma creatinine kinase (CK and lactate dehydrogenase (LDH levels were measured. We also evaluated the histological damage score and wet/dry weight (W/D ratio. Results: The histological damage score, W/D ratio, MPO activity, MDA, TNF-α and IL-1β levels in muscle tissues were significantly increased, SOD activity was decreased, and plasma CK and LDH levels were remarkably elevated in both the IR and CO groups compared to the SM group (P

  11. Radiation-induced DNA damage in tumors and normal tissues. III. Oxygen dependence of the formation of strand breaks and DNA-protein crosslinks

    Zhang, H.; Wallen, C.A.; Wheeler, K.T.; Joch, C.J.

    1995-01-01

    Results from several laboratories, including ours, have suggested that measurements of radiation-induced DNA strand breaks and DNA-protein crosslinks (DPCs) may be used to estimate the hypoxic fraction or fractional hypoxic volume of tumors and normal tissues. This suggestion has been predicated on both published and nonpublished information that (1) the oxygen dependence of the formation of strand breaks in irradiated mammalian cells is similar to the oxygen dependence of radiation-produced cell killing, and (2) the oxygen dependence of the formation of DPCs in irradiated mammalian cells is the mirror image of the oxygen dependence of radiation-induced cell killing. However, the published studies that attempted to determine the relationship between the oxygen dependence of the formation of strand breaks and the radiation sensitivity of mammalian cells were not performed at 37 degrees C, the exact oxygen concentrations were not always known, and the results were conflicting. In addition, most of the data on the oxygen dependence of the formation of DPCs are unpublished. Consequently, we have undertaken a comprehensive investigation of one cell line, 9L/Ro rat brain tumor cells, to determine if the shape of the oxygen dependence curve and the K m value for radiation-induced strand breaks and DPCs were similar when 9L cells were irradiated under both ideal gas-liquid equilibrium conditions at 4 degrees C and nonideal gas-liquid equilibrium conditions at 37 degrees C. At 4 degrees C under ideal gas-liquid equilibrium conditions, the K m for the formation of strand breaks was approximately 0.0045 mM, and Km for radiation sensitivity was approximately 0.005mM. A similar comparison for the formation of DPCs at 4 degrees C could not be made, because the efficiency of the formation of DPC was much lower at 4 degrees C than at 37 degrees C. 30 refs., 3 figs

  12. Natriuretic peptide infusion reduces myocardial injury during acute ischemia/reperfusion

    Kousholt, Birgitte S.; Larsen, Jens Kjærgaard Rolighed; Bisgaard, Line Stattau

    2012-01-01

    Aim: The aim of this study was to determine whether a natriuretic peptide infusion during reperfusion can reduce cardiomyocyte ischemia–reperfusion damage. Materials and methods: The effect of B-type natriuretic peptide (BNP) activity was assessed in vitro and in vivo: the cellular effect...... in apoptotic changes in the BNP-stimulated cells. Pigs tolerated the BNP and CD-NP (a CNP analogue) infusion well, with a decrease in systemic blood pressure (~15 mmHg) and increased diuresis compared with the controls. Left ventricular pressure decreased in the pigs that received BNP infusion compared...... with controls (P=0.02). A similar trend was observed in the pigs that received CD-NP infusion, although this was not significant (P=0.3). BNP and CD-NP infusion in pigs reduced total cardiac troponin T release by 46 and 40%, respectively (P=0.0015 and 0.0019), and were associated with improved RNA integrity...

  13. Natriuretic peptide infusion reduces myocardial injury during acute ischemia/reperfusion

    Kousholt, Birgitte S.; Larsen, Jens Kjærgaard Rolighed; Bisgaard, Line Stattau

    2012-01-01

    Aim: The aim of this study was to determine whether a natriuretic peptide infusion during reperfusion can reduce cardiomyocyte ischemia–reperfusion damage. Materials and methods: The effect of B-type natriuretic peptide (BNP) activity was assessed in vitro and in vivo: the cellular effect...... in apoptotic changes in the BNP-stimulated cells. Pigs tolerated the BNP and CD-NP (a CNP analogue) infusion well, with a decrease in systemic blood pressure (∼15 mmHg) and increased diuresis compared with the controls. Left ventricular pressure decreased in the pigs that received BNP infusion compared...... with controls (P=0.02). A similar trend was observed in the pigs that received CD-NP infusion, although this was not significant (P=0.3). BNP and CD-NP infusion in pigs reduced total cardiac troponin T release by 46 and 40%, respectively (P=0.0015 and 0.0019), and were associated with improved RNA integrity...

  14. Effects of Remote Ischemic Conditioning Methods on Ischemia-Reperfusion Injury in Muscle Flaps: An Experimental Study in Rats

    Durdane Keskin

    2017-09-01

    Full Text Available Background The aim of this study was to investigate the effects of remote ischemic conditioning on ischemia-reperfusion injury in rat muscle flaps histopathologically and biochemically. Methods Thirty albino rats were divided into 5 groups. No procedure was performed in the rats in group 1, and only blood samples were taken. A gracilis muscle flap was elevated in all the other groups. Microclamps were applied to the vascular pedicle for 4 hours in order to achieve tissue ischemia. In group 2, no additional procedure was performed. In groups 3, 4, and 5, the right hind limb was used and 3 cycles of ischemia-reperfusion for 5 minutes each (total, 30 minutes was applied with a latex tourniquet (remote ischemic conditioning. In group 3, this procedure was performed before flap elevation (remote ischemic preconditoning. In group 4, the procedure was performed 4 hours after flap ischemia (remote ischemic postconditioning. In group 5, the procedure was performed after the flap was elevated, during the muscle flap ischemia episode (remote ischemic perconditioning. Results The histopathological damage score in all remote conditioning ischemia groups was lower than in the ischemic-reperfusion group. The lowest histopathological damage score was observed in group 5 (remote ischemic perconditioning. Conclusions The nitric oxide levels were higher in the blood samples obtained from the remote ischemic perconditioning group. This study showed the effectiveness of remote ischemic conditioning procedures and compared their usefulness for preventing ischemia-reperfusion injury in muscle flaps.

  15. Effects of Remote Ischemic Conditioning Methods on Ischemia-Reperfusion Injury in Muscle Flaps: An Experimental Study in Rats.

    Keskin, Durdane; Unlu, Ramazan Erkin; Orhan, Erkan; Erkilinç, Gamze; Bogdaycioglu, Nihal; Yilmaz, Fatma Meric

    2017-09-01

    The aim of this study was to investigate the effects of remote ischemic conditioning on ischemia-reperfusion injury in rat muscle flaps histopathologically and biochemically. Thirty albino rats were divided into 5 groups. No procedure was performed in the rats in group 1, and only blood samples were taken. A gracilis muscle flap was elevated in all the other groups. Microclamps were applied to the vascular pedicle for 4 hours in order to achieve tissue ischemia. In group 2, no additional procedure was performed. In groups 3, 4, and 5, the right hind limb was used and 3 cycles of ischemia-reperfusion for 5 minutes each (total, 30 minutes) was applied with a latex tourniquet (remote ischemic conditioning). In group 3, this procedure was performed before flap elevation (remote ischemic preconditoning). In group 4, the procedure was performed 4 hours after flap ischemia (remote ischemic postconditioning). In group 5, the procedure was performed after the flap was elevated, during the muscle flap ischemia episode (remote ischemic perconditioning). The histopathological damage score in all remote conditioning ischemia groups was lower than in the ischemic-reperfusion group. The lowest histopathological damage score was observed in group 5 (remote ischemic perconditioning). The nitric oxide levels were higher in the blood samples obtained from the remote ischemic perconditioning group. This study showed the effectiveness of remote ischemic conditioning procedures and compared their usefulness for preventing ischemia-reperfusion injury in muscle flaps.

  16. Repetitive postprandial hyperglycemia increases cardiac ischemia/reperfusion injury: prevention by the alpha-glucosidase inhibitor acarbose.

    Frantz, Stefan; Calvillo, Laura; Tillmanns, Jochen; Elbing, Inka; Dienesch, Charlotte; Bischoff, Hilmar; Ertl, Georg; Bauersachs, Johann

    2005-04-01

    Protective effects of the alpha-glucosidase inhibitor acarbose have been reported for various diabetic complications. In the STOP-NIDDM study, even patients without overt diabetes, but with impaired glucose tolerance, had a reduction in cardiovascular events when treated with acarbose. Therefore, we investigated the effect of repetitive postprandial hyperglycemia on the cardiac ischemia/reperfusion injury in vivo. Mice were treated daily by single applications of placebo, sucrose (4 g/kg body weight), or sucrose + acarbose (10 mg/kg body weight) by gavage for 7 days. Acarbose treatment significantly reduced the sucrose-induced increase in plasma glucose concentration. Subsequently, animals underwent 30 min of ischemia by coronary artery ligation and 24 h of reperfusion in vivo. In the sucrose group, ischemia/reperfusion damage was significantly increased (infarct/area at risk, placebo vs. sucrose, 38.8+/-7.5% vs. 62.2+/-4.8%, P<0.05). This was prevented by acarbose treatment (infarct/area at risk 30.7+/-7.2%). While myocardial inflammation was similar in all groups, oxidative stress as indicated by a significant increase in lipid peroxides was enhanced in the sucrose, but not in the sucrose + acarbose group. In summary, repetitive postprandial hyperglycemia increases ischemia/reperfusion damage. This effect can be prevented by treatment with the alpha-glucosidase inhibitor acarbose.

  17. CD47 regulates renal tubular epithelial cell self-renewal and proliferation following renal ischemia reperfusion.

    Rogers, Natasha M; Zhang, Zheng J; Wang, Jiao-Jing; Thomson, Angus W; Isenberg, Jeffrey S

    2016-08-01

    Defects in renal tubular epithelial cell repair contribute to renal ischemia reperfusion injury, cause acute kidney damage, and promote chronic renal disease. The matricellular protein thrombospondin-1 and its receptor CD47 are involved in experimental renal ischemia reperfusion injury, although the role of this interaction in renal recovery is unknown. We found upregulation of self-renewal genes (transcription factors Oct4, Sox2, Klf4 and cMyc) in the kidney of CD47(-/-) mice after ischemia reperfusion injury. Wild-type animals had minimal self-renewal gene expression, both before and after injury. Suggestive of cell autonomy, CD47(-/-) renal tubular epithelial cells were found to increase expression of the self-renewal genes. This correlated with enhanced proliferative capacity compared with cells from wild-type mice. Exogenous thrombospondin-1 inhibited self-renewal gene expression in renal tubular epithelial cells from wild-type but not CD47(-/-) mice, and this was associated with decreased proliferation. Treatment of renal tubular epithelial cells with a CD47 blocking antibody or CD47-targeting small interfering RNA increased expression of some self-renewal transcription factors and promoted cell proliferation. In a syngeneic kidney transplant model, treatment with a CD47 blocking antibody increased self-renewal transcription factor expression, decreased tissue damage, and improved renal function compared with that in control mice. Thus, thrombospondin-1 via CD47 inhibits renal tubular epithelial cell recovery after ischemia reperfusion injury through inhibition of proliferation/self-renewal. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  18. Effects of a human recombinant alkaline phosphatase on renal hemodynamics, oxygenation and inflammation in two models of acute kidney injury

    Peters, Esther, E-mail: esther.peters@radboudumc.nl [Department of Intensive Care Medicine, Radboud university medical center, PO Box 9101, Internal Mailbox 710, 6500 HB, Nijmegen (Netherlands); Department of Pharmacology and Toxicology, Radboud university medical center, PO Box 9101, Internal Mailbox 149, 6500 HB, Nijmegen (Netherlands); Ergin, Bülent, E-mail: b.ergin@amc.uva.nl [Department of Translational Physiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands); Kandil, Asli, E-mail: aslikandil@istanbul.edu.tr [Department of Biology, Faculty of Science, Istanbul University, PK 34134, Vezneciler, Istanbul (Turkey); Gurel-Gurevin, Ebru, E-mail: egurelgurevin@gmail.com [Department of Biology, Faculty of Science, Istanbul University, PK 34134, Vezneciler, Istanbul (Turkey); Elsas, Andrea van, E-mail: a.vanelsas@am-pharma.com [AM-Pharma, Rumpsterweg 6, 3981 AK, Bunnik (Netherlands); Masereeuw, Rosalinde, E-mail: r.masereeuw@uu.nl [Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, PO Box 80082, 3508 TB Utrecht (Netherlands); Pickkers, Peter, E-mail: peter.pickkers@radboudumc.nl [Department of Intensive Care Medicine, Radboud university medical center, PO Box 9101, Internal Mailbox 710, 6500 HB, Nijmegen (Netherlands); Ince, Can, E-mail: c.ince@amc.uva.nl [Department of Translational Physiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands)

    2016-12-15

    Two small clinical trials indicated that administration of bovine intestinal alkaline phosphatase (AP) improves renal function in critically ill patients with sepsis-associated acute kidney injury (AKI), for which the mechanism of action is not completely understood. Here, we investigated the effects of a newly developed human recombinant AP (recAP) on renal oxygenation and hemodynamics and prevention of kidney damage and inflammation in two in vivo AKI models. To induce AKI, male Wistar rats (n = 18) were subjected to renal ischemia (30 min) and reperfusion (I/R), or sham-operated. In a second model, rats (n = 18) received a 30 min infusion of lipopolysaccharide (LPS; 2.5 mg/kg), or saline, and fluid resuscitation. In both models, recAP (1000 U/kg) was administered intravenously (15 min before reperfusion, or 90 min after LPS). Following recAP treatment, I/R-induced changes in renal blood flow, renal vascular resistance and oxygen delivery at early, and cortical microvascular oxygen tension at late reperfusion were no longer significantly affected. RecAP did not influence I/R-induced effects on mean arterial pressure. During endotoxemia, recAP treatment did not modulate the LPS-induced changes in systemic hemodynamics and renal oxygenation. In both models, recAP did exert a clear renal protective anti-inflammatory effect, demonstrated by attenuated immunostaining of inflammatory, tubular injury and pro-apoptosis markers. Whether this renal protective effect is sufficient to improve outcome of patients suffering from sepsis-associated AKI is being investigated in a large clinical trial. - Highlights: • Human recombinant alkaline phosphatase (recAP) is a potential new therapy for sepsis-associated acute kidney injury (AKI). • RecAP can modulate renal oxygenation and hemodynamics immediately following I/R-induced AKI. • RecAP did not modulate endotoxemia-induced changes in systemic hemodynamics and renal oxygenation. • RecAP did exert a clear renal protective

  19. Constants of the Alper and Howard-Flanders oxygen equation for damage to bacterial membrane, deduced from observations on the radiation-induced penicillin-sensitive lesion

    Obioha, F.I.; Gillies, N.E.; Cullen, B.M.; Walker, H.C.; Alper, T.

    1984-01-01

    E. coli were irradiated in the presence of 100% oxygen, oxygen-free nitrogen and mixtures of 1.01, 0.59, 0.3, 0.1 and 0.06% oxygen in nitrogen. Changes in sensitivity with pO 2 conformed with the Alper and Howard-Flanders equation for bacteria treated after irradiation by penicillin as well as for the untreated ones. Values of m were respectively 4.8 and 3.3; values of K were identical, within experimental error, (4.4 mmHg). Sensitivity to induction of the bacterial membrane penicillin-sensitive lesion was calculated from the difference in the reciprocals of D 0 values proper to untreated and treated bacteria, for every gas used. The value of m could not be directly calculated because the effect of penicillin on anoxically irradiated bacteria was not detectable. For that reason, a transformation of the oxygen equation was used, allowing estimates to be made of both m and K, provided the results conformed with the equation. Within experimental error they did. Calculated values of m and K for induction of the penicillin-sensitive lesion were respectively 8 and 5.9 mmHg, but it is shown that the oxygen enhancement ratio was probably underestimated and the value overestimated. (author)

  20. Delayed xenon post-conditioning mitigates spinal cord ischemia/reperfusion injury in rabbits by regulating microglial activation and inflammatory factors.

    Yang, Yan-Wei; Wang, Yun-Lu; Lu, Jia-Kai; Tian, Lei; Jin, Mu; Cheng, Wei-Ping

    2018-03-01

    The neuroprotective effect against spinal cord ischemia/reperfusion injury in rats exerted by delayed xenon post-conditioning is stronger than that produced by immediate xenon post-conditioning. However, the mechanisms underlying this process remain unclear. Activated microglia are the main inflammatory cell type in the nervous system. The release of pro-inflammatory factors following microglial activation can lead to spinal cord damage, and inhibition of microglial activation can relieve spinal cord ischemia/reperfusion injury. To investigate how xenon regulates microglial activation and the release of inflammatory factors, a rabbit model of spinal cord ischemia/reperfusion injury was induced by balloon occlusion of the infrarenal aorta. After establishment of the model, two interventions were given: (1) immediate xenon post-conditioning-after reperfusion, inhalation of 50% xenon for 1 hour, 50% N 2 /50%O 2 for 2 hours; (2) delayed xenon post-conditioning-after reperfusion, inhalation of 50% N 2 /50%O 2 for 2 hours, 50% xenon for 1 hour. At 4, 8, 24, 48 and 72 hours after reperfusion, hindlimb locomotor function was scored using the Jacobs locomotor scale. At 72 hours after reperfusion, interleukin 6 and interleukin 10 levels in the spinal cord of each group were measured using western blot assays. Iba1 levels were determined using immunohistochemistry and a western blot assay. The number of normal neurons at the injury site was quantified using hematoxylin-eosin staining. At 72 hours after reperfusion, delayed xenon post-conditioning remarkably enhanced hindlimb motor function, increased the number of normal neurons at the injury site, decreased Iba1 levels, and inhibited interleukin-6 and interleukin-10 levels in the spinal cord. Immediate xenon post-conditioning did not noticeably affect the above-mentioned indexes. These findings indicate that delayed xenon post-conditioning after spinal cord injury improves the recovery of neurological function by reducing

  1. Anticancer Drug 2-Methoxyestradiol Protects against Renal Ischemia/Reperfusion Injury by Reducing Inflammatory Cytokines Expression

    Ying-Yin Chen

    2014-01-01

    Full Text Available Background. Ischemia/reperfusion (I/R injury is a major cause of acute renal failure and allograft dysfunction in kidney transplantation. ROS/inflammatory cytokines are involved in I/R injury. 2-Methoxyestradiol (2ME2, an endogenous metabolite of estradiol, inhibits inflammatory cytokine expression and is an antiangiogenic and antitumor agent. We investigated the inhibitory effect of 2ME2 on renal I/R injury and possible molecular actions. Methods. BALB/c mice were intraperitoneally injected with 2ME2 (10 or 20 mg/kg or vehicle 12 h before and immediately after renal I/R experiments. The kidney weight, renal function, tubular damages, and apoptotic response were examined 24 h after I/R injury. The expression of mRNA of interleukin-1β, tumor necrosis factor- (TNF α, caspase-3, hypoxia inducible factor- (HIF 1α, and proapoptotic Bcl-2/adenovirus E1B 19 kDa interacting protein 3 (BNIP3 in kidney tissue was determined using RT-PCR, while the expression of nuclear factor κB (NF-κB, BCL-2, and BCL-xL, activated caspase-9, and HIF-1α was determined using immunoblotting. In vitro, we determined the effect of 2ME2 on reactive oxygen species (ROS production and cell viability in antimycin-A-treated renal mesangial (RMC and tubular (NRK52E cells. Results. Serum creatinine and blood urea nitrogen were significantly higher in mice with renal I/R injury than in sham control and in I/R+2ME2-treated mice. Survival in I/R+2ME2-treated mice was higher than in I/R mice. Histological examination showed that 2ME2 attenuated tubular damage in I/R mice, which was associated with lower expression TNF-α, IL-1β, caspase-9, HIF-1α, and BNIP3 mRNA in kidney tissue. Western blotting showed that 2ME2 treatment substantially decreased the expression of activated caspase-9, NF-κB, and HIF-1α but increased the antiapoptotic proteins BCL-2 and BCL-xL in kidney of I/R injury. In vitro, 2MR2 decreased ROS production and increased cell viability in antimycin

  2. Refocusing Neuroprotection in Cerebral Reperfusion Era: New Challenges and Strategies

    Xiao-Yi Xiong

    2018-04-01

    Full Text Available Pathophysiological processes of stroke have revealed that the damaged brain should be considered as an integral structure to be protected. However, promising neuroprotective drugs have failed when translated to clinical trials. In this review, we evaluated previous studies of neuroprotection and found that unsound patient selection and evaluation methods, single-target treatments, etc., without cerebral revascularization may be major reasons of failed neuroprotective strategies. Fortunately, this may be reversed by recent advances that provide increased revascularization with increased availability of endovascular procedures. However, the current improved effects of endovascular therapy are not able to match to the higher rate of revascularization, which may be ascribed to cerebral ischemia/reperfusion injury and lacking of neuroprotection. Accordingly, we suggest various research strategies to improve the lower therapeutic efficacy for ischemic stroke treatment: (1 multitarget neuroprotectant combinative therapy (cocktail therapy should be investigated and performed based on revascularization; (2 and more efforts should be dedicated to shifting research emphasis to establish recirculation, increasing functional collateral circulation and elucidating brain–blood barrier damage mechanisms to reduce hemorrhagic transformation. Therefore, we propose that a comprehensive neuroprotective strategy before and after the endovascular treatment may speed progress toward improving neuroprotection after stroke to protect against brain injury.

  3. [Approach to the relationship between the changes of the content of free zinc in hippocampus and ischemic neuronal damage].

    Zhou, Zhu-Juan; Zheng, Jian; He, Ying

    2002-08-01

    To make approach to the relationship between the changes of free zinc and ischemic neuronal damage in hippocampus after forebrain ischemia/reperfusion. The models of forebrain ischemia/reperfusion were established in rats. The contents of free Zn2+ were measured by TSQ fluorescence method. The Zn2+ chelator (CaEDTA) was injected into lateral ventricles in order to evaluate the effect of free Zn2+ on ischemic neuronal damage. (1) Zn2+ fluorescence in the hilus of dentate gyrus, CA3 region and the stratum radiatum and stratum oriens of CA1 decreased slightly at forty-eight hours after reperfusion. From seventy-two hours to ninety-six hour after reperfusion, the decreased fluorescence gradually returned to the normal level, but some fluorescence dots were found in pyramidal neurons of CA1 and the hilus of dentate gyrus. Seven days after reperfusion, all the changes of the fluorescence almost recovered. (2) The cell membrane-impermeable Zn2+ chelator CaEDTA could reduce the intracellular concentration of free Zn2+ and reduced neuronal damage after forebrain ischemia/reperfusion. (1) The synaptic vesicle Zn2+ released and then translocated into postsynaptic neurons after forebrain ischemia/reperfusion and played a role in ischemic neuronal damage. (2) The cell membrane-impermeable chelator CaEDTA could provide neuroprotection.

  4. The effect of adhesion molecule blockade on pulmonary reperfusion injury.

    Levine, Adrian J; Parkes, Karen; Rooney, Stephen J; Bonser, Robert S

    2002-04-01

    Selectins are the molecules involved in the initial adhesion of the activated neutrophil on pulmonary endothelium. We investigated the efficacy of selectin blockade in a selective (monoclonal antibody RMP-1) and nonselective (Fucoidin) manner in pulmonary reperfusion injury. Groups of six rat lungs were flushed with University of Wisconsin solution then stored at 4 degrees C for 4 hours. They then underwent sanguinous reperfusion for 30 minutes during which functional measures (gas exchange, pulmonary artery pressure, and airway pressure) of lung performance were made. After reperfusion we estimated their capillary filtration coefficient (Kfc units g/cm water/minute/g wet lung tissue) using a gravimetric technique. Four groups were studied: group I had no reperfusion, group II had 30 minutes of reperfusion, group III had infusion of 20 mg/kg Fucoidin before reperfusion, and group IV had infusion of 20 microg/mL RMP-1 before reperfusion. Reperfusion injury was found between groups I and II by an increase in capillary filtration coefficient (1.048 +/- 0.316 to 3.063 +/- 0.466, p Kfc than group II (0.967 +/- 0.134 and 1.205 +/- 0.164, respectively, p < 0.01). There was no significant functional difference between groups II, III, and IV. Reperfusion-induced hyperpermeability was ameliorated by selective (RMP-1) and nonselective (Fucoidin) selectin blockade.

  5. Edaravone enhances the viability of ischemia/reperfusion flaps.

    Zhang, Dong-Yi; Kang, Shen-Song; Zhang, Zheng-Wen; Wu, Rui

    2017-02-01

    in the edaravone-treated IR group were significantly lower than those in the IR group. The activity of SOD, flap viability and average number of subcutaneous vessels in the edaravone-treated IR group were significantly higher than those in the IR group. All the differences were statistically significant. The ultrastructure injury of vascular endothelial cells in the edaravone-treated IR group was slighter than that in IR group. It was concluded that edaravone can significantly enhance IR flap viability and protect flap vessels, which is related to scavenging oxygen free radicals, reducing the consumption of SOD, reducing the extent of lipid peroxidation and inflammation, and protecting functional structure of vessels in the early stages of reperfusion.

  6. Obestatin Accelerates the Recovery in the Course of Ischemia/Reperfusion-Induced Acute Pancreatitis in Rats.

    Jakub Bukowczan

    Full Text Available Several previous studies have shown that obestatin exhibits protective and regenerative effects in some organs including the stomach, kidney, and the brain. In the pancreas, pretreatment with obestatin inhibits the development of cerulein-induced acute pancreatitis, and promotes survival of pancreatic beta cells and human islets. However, no studies investigated the effect of obestatin administration following the onset of experimental acute pancreatitis.The aim of this study was to evaluate the impact of obestatin therapy in the course of ischemia/reperfusion-induced pancreatitis. Moreover, we tested the influence of ischemia/reperfusion-induced acute pancreatitis and administration of obestatin on daily food intake and pancreatic exocrine secretion.Acute pancreatitis was induced by pancreatic ischemia followed by reperfusion of the pancreas. Obestatin (8 nmol/kg/dose was administered intraperitoneally twice a day, starting 24 hours after the beginning of reperfusion. The effect of obestatin in the course of necrotizing pancreatitis was assessed between 2 and 14 days, and included histological, functional, and biochemical analyses. Secretory studies were performed on the third day after sham-operation or induction of acute pancreatitis in conscious rats equipped with chronic pancreatic fistula.Treatment with obestatin ameliorated morphological signs of pancreatic damage including edema, vacuolization of acinar cells, hemorrhages, acinar necrosis, and leukocyte infiltration of the gland, and led to earlier pancreatic regeneration. Structural changes were accompanied by biochemical and functional improvements manifested by accelerated normalization of interleukin-1β level and activity of myeloperoxidase and lipase, attenuation of the decrease in pancreatic DNA synthesis, and by an improvement of pancreatic blood flow. Induction of acute pancreatitis by pancreatic ischemia followed by reperfusion significantly decreased daily food intake and

  7. Platelet aggregation but not activation and degranulation during the acute post-ischemic reperfusion phase in livers with no underlying disease

    van Golen, Rowan F.; Stevens, Katarzyna M.; Colarusso, Pina; Jaeschke, Hartmut; Heger, Michal

    2015-01-01

    Platelets and P-selectin (CD62P) play an unequivocal role in the pathology of hepatic ischemia/reperfusion (I/R) injury. Inhibition or knock-out of P-selectin or immunodepletion of platelets results in amelioration of post-ischemic inflammation, reduced hepatocellular damage, and improved survival.

  8. The calcium-binding protein complex S100A8/A9 has a crucial role in controlling macrophage-mediated renal repair following ischemia/reperfusion

    Dessing, Mark C.; Tammaro, Alessandra; Pulskens, Wilco P.; Teske, Gwendoline J.; Butter, Loes M.; Claessen, Nike; van Eijk, Marco; van der Poll, Tom; Vogl, Thomas; Roth, Johannes; Florquin, Sandrine; Leemans, Jaklien C.

    2015-01-01

    Upon ischemia/reperfusion (I/R)-induced injury, several damage-associated molecular patterns are expressed including the calcium-binding protein S100A8/A9 complex. S100A8/A9 can be recognized by Toll-like receptor-4 and its activation is known to deleteriously contribute to renal I/R-induced injury.

  9. Data on administration of cyclosporine, nicorandil, metoprolol on reperfusion related outcomes in ST-segment Elevation Myocardial Infarction treated with percutaneous coronary intervention

    Campo, Gianluca; Pavasini, Rita; Morciano, Giampaolo

    2017-01-01

    Mortality and morbidity in patients with ST elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI) are still high [1]. A huge amount of the myocardial damage is related to the mitochondrial events happening during reperfusion [2]. Several drugs direc...

  10. Evidence that estrogen receptors play a limited role in mediating enhanced recovery of bile flow in female rats in the acute phase of liver ischemia reperfusion injury

    de Vries, Heleen A. H.; Ponds, Fraukje A. M.; Nieuwenhuijs, Vincent B.; Morphett, Arthur; Padbury, Robert T. A.; Barritt, Greg J.

    2013-01-01

    Introduction. Female patients exhibit better survival and less hepatic damage from ischemia reperfusion (IR) injury following surgery. However, the effects of sex and estrogens on liver function in the acute phase of IR are not well understood. Objective. The aim was to investigate this question.

  11. Small CAB-like proteins prevent formation of singlet oxygen in the damaged photosystem II complex of the cyanobacterium Synechocystis sp PCC 6803

    Sinha, R. K.; Komenda, Josef; Knoppová, Jana; Sedlářová, M.; Pospíšil, P.

    2012-01-01

    Roč. 35, č. 4 (2012), s. 806-818 ISSN 0140-7791 R&D Projects: GA MŠk(CZ) ED2.1.00/03.0110; GA ČR(CZ) GAP501/11/0377 Institutional research plan: CEZ:AV0Z50200510 Keywords : oxidative stress * photoinhibition * reactive oxygen species Subject RIV: EE - Microbiology, Virology Impact factor: 5.135, year: 2012

  12. Protective Effect of Urtica dioica on Liver Injury Induced By Hepatic Ischemia Reperfusion Injury in Rats

    Alpaslan TERZİ

    2010-05-01

    Full Text Available Background: This study was designed to investigate the effects of Urtica dioica on liverischemia reperfusion injury in rats. Methods: Thirty male Wistar-albino rats were used in this experimental study. Animals weredivided into three groups as sham operated (group 1, control (group 2, and Urtica dioicatreatment group (group 3. Urtica dioica 2ml/kg were administered intraperitoneally beforeischemia and immediately after the reperfusion. The levels of total antioxidant capacity, totalfree sulfidril group, Total oxidant status, Oxidative stress index, and myeloperoxidase in livertissues were measured. The serum levels of ALT, AST and LDH were also measuredResults: Total antioxidant capacity and total free sulfidril group in liver tissue were significantlyhigher in group 3 than in group 2. Oxidative stress index and myeloperoxidase in liver tissuewere significantly lower in group 3 than the group 2. The levels of liver enzymes in treatmentgroup were significantly lower than those in the control group. Histological tissue damage wasmilder in the treatment group than that in the control group.Conclusion: It is concluded that Urtica dioica increase the antioxidant capacity and decreaseoxidative stress and liver enzymes in the hepatic ischemi reperfusion injury of rats.

  13. Effects of Urtica dioica on hepatic ischemia-reperfusion injury in rats.

    Kandis, Hayati; Karapolat, Sami; Yildirim, Umran; Saritas, Ayhan; Gezer, Suat; Memisogullari, Ramazan

    2010-01-01

    To evaluate the effects of Urtica dioica on hepatic ischemia-reperfusion injury. Thirty adult male Wistar albino rats were divided into three groups: sham group (group 1), control group (group 2), and Urtica dioica group (group 3). All the rats were exposed to hepatic ischemia for 60 min, followed by 60 min of reperfusion. In group 2, a total of 2 ml/kg 0.9% saline solution was given intraperitoneally. In group 3, a total of 2 ml/kg Urtica dioica was given intraperitoneally. At the end of the procedure, liver tissue and blood samples were taken from all rats. Serum aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, ceruloplasmin, catalase, paraoxonase, arylesterase, and lipid hydroperoxide levels were measured. Liver tissue histopathologies were also evaluated by light microscopy. Serum aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase levels were significantly higher in group 2 than in group 1, and significantly lower in group 3 than in group 2. Also, group 2 had higher serum lipid hydroperoxides and ceruloplasmin levels but lower catalase, paraoxonase, and arylesterase levels than group 1. In group 3, serum lipid hydroperoxides and ceruloplasmin levels were significantly lower, and catalase, paraoxonase, and arylesterase levels were higher than those in group 2. Histopathological examination showed that liver tissue damage was significantly decreased in group 3 compared with group 2. Urtica dioica has a protective effect on the liver in hepatic ischemia-reperfusion-injured rats.

  14. Hypoxia-regulated therapeutic gene as a preemptive treatment strategy against ischemia/reperfusion tissue injury.

    Pachori, Alok S; Melo, Luis G; Hart, Melanie L; Noiseux, Nicholas; Zhang, Lunan; Morello, Fulvio; Solomon, Scott D; Stahl, Gregory L; Pratt, Richard E; Dzau, Victor J

    2004-08-17

    Ischemia and reperfusion represent major mechanisms of tissue injury and organ failure. The timing of administration and the duration of action limit current treatment approaches using pharmacological agents. In this study, we have successfully developed a preemptive strategy for tissue protection using an adenoassociated vector system containing erythropoietin hypoxia response elements for ischemia-regulated expression of the therapeutic gene human heme-oxygenase-1 (hHO-1). We demonstrate that a single administration of this vector several weeks in advance of ischemia/reperfusion injury to multiple tissues such as heart, liver, and skeletal muscle yields rapid and timely induction of hHO-1 during ischemia that resulted in dramatic reduction in tissue damage. In addition, overexpression of therapeutic transgene prevented long-term pathological tissue remodeling and normalized tissue function. Application of this regulatable system using an endogenous physiological stimulus for expression of a therapeutic gene may be a feasible strategy for protecting tissues at risk of ischemia/reperfusion injury.

  15. Hypoxia-regulated therapeutic gene as a preemptive treatment strategy against ischemia/reperfusion tissue injury

    Pachori, Alok S.; Melo, Luis G.; Hart, Melanie L.; Noiseux, Nicholas; Zhang, Lunan; Morello, Fulvio; Solomon, Scott D.; Stahl, Gregory L.; Pratt, Richard E.; Dzau, Victor J.

    2004-08-01

    Ischemia and reperfusion represent major mechanisms of tissue injury and organ failure. The timing of administration and the duration of action limit current treatment approaches using pharmacological agents. In this study, we have successfully developed a preemptive strategy for tissue protection using an adenoassociated vector system containing erythropoietin hypoxia response elements for ischemia-regulated expression of the therapeutic gene human heme-oxygenase-1 (hHO-1). We demonstrate that a single administration of this vector several weeks in advance of ischemia/reperfusion injury to multiple tissues such as heart, liver, and skeletal muscle yields rapid and timely induction of hHO-1 during ischemia that resulted in dramatic reduction in tissue damage. In addition, overexpression of therapeutic transgene prevented long-term pathological tissue remodeling and normalized tissue function. Application of this regulatable system using an endogenous physiological stimulus for expression of a therapeutic gene may be a feasible strategy for protecting tissues at risk of ischemia/reperfusion injury.

  16. Short-term dietary restriction and fasting precondition against ischemia reperfusion injury in mice.

    Mitchell, James R; Verweij, Mariëlle; Brand, Karl; van de Ven, Marieke; Goemaere, Natascha; van den Engel, Sandra; Chu, Timothy; Forrer, Flavio; Müller, Cristina; de Jong, Marion; van IJcken, Wilfred; IJzermans, Jan N M; Hoeijmakers, Jan H J; de Bruin, Ron W F

    2010-02-01

    Dietary restriction (DR) extends lifespan and increases resistance to multiple forms of stress, including ischemia reperfusion injury to the brain and heart in rodents. While maximal effects on lifespan require long-term restriction, the kinetics of onset of benefits against acute stress is not known. Here, we show that 2-4 weeks of 30% DR improved survival and kidney function following renal ischemia reperfusion injury in mice. Brief periods of water-only fasting were similarly effective at protecting against ischemic damage. Significant protection occurred within 1 day, persisted for several days beyond the fasting period and extended to another organ, the liver. Protection by both short-term DR and fasting correlated with improved insulin sensitivity, increased expression of markers of antioxidant defense and reduced expression of markers of inflammation and insulin/insulin-like growth factor-1 signaling. Unbiased transcriptional profiling of kidneys from mice subject to short-term DR or fasting revealed a significant enrichment of signature genes of long-term DR. These data demonstrate that brief periods of reduced food intake, including short-term daily restriction and fasting, can increase resistance to ischemia reperfusion injury in rodents and suggest a rapid onset of benefits of DR in mammals.

  17. Neuroprotective Effect of β-Caryophyllene on Cerebral Ischemia-Reperfusion Injury via Regulation of Necroptotic Neuronal Death and Inflammation: In Vivo and in Vitro

    Mei Yang

    2017-10-01

    Full Text Available Necrotic cell death is a hallmark feature of ischemic stroke and it may facilitate inflammation by releasing intracellular components after cell-membrane rupture. Previous studies reported that β-caryophyllene (BCP mitigates cerebral ischemia-reperfusion (I/R injury, but the underlying mechanism remains unclear. We explored whether BCP exerts a neuroprotective effect in cerebral I/R injury through inhibiting necroptotic cell death and inflammation. Primary neurons with and without BCP (0.2, 1, 5, 25 μM treatment were exposed to oxygen-glucose deprivation and re-oxygenation (OGD/R. Neuron damage, neuronal death type and mixed lineage kinase domain-like (MLKL protein expression were assessed 48 h after OGD/R. Furthermore, mice underwent I/R procedures with or without BCP (8, 24, 72 mg/kg, ip.. Neurologic dysfunction, cerebral infarct volumes, cell death, cytokine levels, necroptosis core molecules, and HMGB1-TLR4 signaling were determined at 48 h after I/R. BCP (5 μM significantly reduced necroptotic neurons and MLKL protein expression following OGD/R. BCP (24, 72 mg/kg, ip. reduced infarct volumes, neuronal necrosis, receptor-interaction protein kinase-1 (RIPK1, receptor-interaction protein kinase-3 (RIPK3 expression, and MLKL phosphorylation after I/R injury. BCP also decreased high-mobility group box 1 (HMGB1, toll-like receptor 4 (TLR4, interleukin-1β (IL-1β, and tumor necrosis factor-α (TNF-α levels. Thus, BCP alleviates ischemic brain damage potentially by inhibiting necroptotic neuronal death and inflammatory response. This study suggests a novel application for BCP as a neuroprotective agent.

  18. The Effect of Lidocaine Enriched Cardioplegia on Myocardial Ischemia-Reperfusion Injury

    Emin Ata

    2016-07-01

    Full Text Available Aim: Most of the complications after open heart surgery is usually associated with ischemia reperfusion injury that develops during cardiopulmoner bypass. In ischemia and reperfusion periods lidocaine blocks intracelluler sodium and calcium channels and protect cell membrane against reactive oxygen metabolites. In this study, lidocaine added to cardioplegia solution and its effects on myocardial ischemia-reperfusion injury was examined. Material and Method: 36 patients who underwent elective coronary artery bypass surgery in our clinic between September 2005 and April 2006 was studied. Patients included into two groups. In study group patients (groupe I 2 mg/kg lidocaine was added into cardioplegia solution that is used during aortic cross clamp period; standart cardioplegia solution was used in control group patients (group II. Postoperative 6. and 24. hours cardiac enzyme levels, inotropic support requirement and atrial fibrilation incidence were compared in both groups. Results: In this study, 36 patients (13 women, 23 man whose average age was 63(±5,5, age range 50-70 years and ventriculer functions were not deformed (EF>40% were involved. There were no significantly differences in demographic datas between towo groups. There were no significantly differences in postoperative 6. and 24. hours troponin-I and CK-MB levels, inotropic support or defibrilation requirement and postoperative atrial fibrilation incidence between two groups. Discussion: Addition of 2 mg/kg dosage lidocaine into cardioplegia solution dont effect cardiac enzyme levels, inotropic support requirement and postoperative atrial fibrilation insidence and it doesnt prevent ischemia-reperfusion injury.

  19. 99mTc-Annexin-V uptake in a rat model of variable ischemic severity and reperfusion time

    Taki, Junichi; Higuchi, Takahiro; Kawashima, Atsuhiro; Muramori, Akira; Nakajima, Kenichi; Tait, J.F.; Matsunari, Ichiro; Vanderheyden, J.L.; Strauss, H.W.

    2007-01-01

    The background of this study was to determine whether mild to moderate ischemia that is not severe enough to induce myocardial infarction will cause myocardial cell damage or apoptosis, the 99m Tc-Annexin-V (Tc-A) uptake was studied in groups of rats with various intervals of coronary occlusion and reperfusion times. After left coronary artery occlusion for 15 min (n=23), 10 min (n=23), or 5 min (n=12), Tc-A (80-150 MBq) was injected at 0.5, 1.5, 6, or 24 h after reperfusion. One hour later, to verify the area at risk, 201 Tl (0.74 MBq) was injected just after left coronary artery re-occlusion and the rats were killed 1 min later. Dual tracer autoradiography was performed to assess Tc-A uptake and area at risk. In all 5-min occlusion and reperfusion models, no significant Tc-A uptake was observed in the area at risk. Tc-A uptake ratios in the 15-min and 10-min ischemia models were 4.46±3.16 and 2.02±0.47 (p=0.078) at 0.5 h after reperfusion, 3.49±1.78 and 1.47±0.11 (p<0.05) at 1.5 h after reperfusion, 1.60±0.43 and 1.34±0.23 (p=0.24) at 6 h after reperfusion, 1.50±0.33 and 1.28±0.33 (p=0.099) at 24 h after reperfusion, respectively. With 15-min ischemia, in 3 of the 5 rats there were a few micro-foci of myocardial cell degeneration and cell infiltration in less than 1% of the ischemic area at 24 h after reperfusion. No significant histological change was observed in rats with 10-min or 5-min ischemia. The data indicate that Tc-A binding depends on the severity of ischemia even without a significant amount of histological change or infarction. (author)

  20. Conditionnement pharmacologique par la ciclosporine A dans l’ischémie-reperfusion rénale

    Lemoine , Sandrine

    2014-01-01

    Ischemia-reperfusion (IR) is a situation encountered in transplantation or during aortic surgery, which can result in renal damages, requiring sometimes transient or definitive dialysis. Mitochondria play a crucial role in the pathophysiology of IR causing cell death. Previous studies of cardiac IR highlighted the role of mitochondrial permeability transition pore (mPTP). Cyclosporin A (CsA) has been proposed as a treatment to protect the kidney from IR by the delay of the opening of the mPTP...

  1. The Effect of Recombinant Human MG53 Protein on Tourniquet-induced Ischemia Reperfusion Injury in Rat Muscle

    2014-06-01

    blind to the treatment , and the prevalence of damaged fibers was quantitated from 10 10x images from each muscle . Approximately 800 fibers were counted...therapeutic cell membrane repair in treatment of muscular dystrophy . Sci Transl Med. 2012; 4(139):139ra185. 11. Weisleder N, Lin P, Zhao X, Orange M, Zhu H...The effect of recombinant human MG53 protein on tourniquet- induced ischemia reperfusion injury in rat muscle Benjamin T. Corona, Ph.D.1, Koyal Garg

  2. Isoflurane anesthesia initiated at the onset of reperfusion attenuates oxidative and hypoxic-ischemic brain injury.

    Sergey A Sosunov

    Full Text Available This study demonstrates that in mice subjected to hypoxia-ischemia (HI brain injury isoflurane anesthesia initiated upon reperfusion limits a release of mitochondrial oxidative radicals by inhibiting a recovery of complex-I dependent mitochondrial respiration. This significantly attenuates an oxidative stress and reduces the extent of HI brain injury. Neonatal mice were subjected to HI, and at the initiation of reperfusion were exposed to isoflurane with or without mechanical ventilation. At the end of HI and isoflurane exposure cerebral mitochondrial respiration, H2O2 emission rates were measured followed by an assessment of cerebral oxidative damage and infarct volumes. At 8 weeks after HI navigational memory and brain atrophy were assessed. In vitro, direct effect of isoflurane on mitochondrial H2O2 emission was compared to that of complex-I inhibitor, rotenone. Compared to controls, 15 minutes of isoflurane anesthesia inhibited recovery of the compex I-dependent mitochondrial respiration and decreased H2O2 production in mitochondria supported with succinate. This was associated with reduced oxidative brain injury, superior navigational memory and decreased cerebral atrophy compared to the vehicle-treated HI-mice. Extended isoflurane anesthesia was associated with sluggish recovery of cerebral blood flow (CBF and the neuroprotection was lost. However, when isoflurane anesthesia was supported with mechanical ventilation the CBF recovery improved, the event associated with further reduction of infarct volume compared to HI-mice exposed to isoflurane without respiratory support. Thus, in neonatal mice brief isoflurane anesthesia initiated at the onset of reperfusion limits mitochondrial release of oxidative radicals and attenuates an oxidative stress. This novel mechanism contributes to neuroprotective action of isoflurane. The use of mechanical ventilation during isoflurane anesthesia counterbalances negative effect of isoflurane anesthesia on

  3. Aging aggravates long-term renal ischemia-reperfusion injury in a rat model.

    Xu, Xianlin; Fan, Min; He, Xiaozhou; Liu, Jipu; Qin, Jiandi; Ye, Jianan

    2014-03-01

    Ischemia-reperfusion injury (IRI) has been considered as the major cause of acute kidney injury and can result in poor long-term graft function. Functional recovery after IRI is impaired in the elderly. In the present study, we aimed to compare kidney morphology, function, oxidative stress, inflammation, and development of renal fibrosis in young and aged rats after renal IRI. Rat models of warm renal IRI were established by clamping left pedicles for 45 min after right nephrectomy, then the clamp was removed, and kidneys were reperfused for up to 12 wk. Biochemical and histologic renal damage were assessed at 12 wk after reperfusion. The immunohistochemical staining of monocyte macrophage antigen-1 (ED-1) and transforming growth factor beta 1 (TGF-β1) and messenger RNA level of TGF-β1 in the kidney were analyzed. Renal IRI caused significant increases of malondialdehyde and 8-hydroxydeoxyguanosine levels and a decrease of superoxide dismutase activity in young and aged IRI rats; however, these changes were more obvious in the aged rats. IRI resulted in severe inflammation and tubulointerstitial fibrosis with decreased creatinine (Cr) clearance and increased histologic damage in aged rats compared with young rats. Moreover, we measured the ratio of Cr clearance between young and aged IRI rats. It demonstrated that aged IRI rats did have poor Cr clearance compared with the young IRI rats. ED-1 and TGF-β1 expression levels in the kidney were significantly higher in aged rats than in young rats after IRI. Aged rats are more susceptible to IRI-induced renal failure, which may associate with the increased oxidative stress, increased histologic damage, and increased inflammation and tubulointerstitial fibrosis. Targeting oxidative stress and inflammatory response should improve the kidney recovery after IRI. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Pomegranate extract protects against cerebral ischemia/reperfusion injury and preserves brain DNA integrity in rats.

    Ahmed, Maha A E; El Morsy, Engy M; Ahmed, Amany A E

    2014-08-21

    Interruption to blood flow causes ischemia and infarction of brain tissues with consequent neuronal damage and brain dysfunction. Pomegranate extract is well tolerated, and safely consumed all over the world. Interestingly, pomegranate extract has shown remarkable antioxidant and anti-inflammatory effects in experimental models. Many investigators consider natural extracts as novel therapies for neurodegenerative disorders. Therefore, this study was carried out to investigate the protective effects of standardized pomegranate extract against cerebral ischemia/reperfusion-induced brain injury in rats. Adult male albino rats were randomly divided into sham-operated control group, ischemia/reperfusion (I/R) group, and two other groups that received standardized pomegranate extract at two dose levels (250, 500 mg/kg) for 15 days prior to ischemia/reperfusion (PMG250+I/R, and PMG500+I/R groups). After I/R or sham operation, all rats were sacrificed and brains were harvested for subsequent biochemical analysis. Results showed reduction in brain contents of MDA (malondialdehyde), and NO (nitric oxide), in addition to enhancement of SOD (superoxide dismutase), GPX (glutathione peroxidase), and GRD (glutathione reductase) activities in rats treated with pomegranate extract prior to cerebral I/R. Moreover, pomegranate extract decreased brain levels of NF-κB p65 (nuclear factor kappa B p65), TNF-α (tumor necrosis factor-alpha), caspase-3 and increased brain levels of IL-10 (interleukin-10), and cerebral ATP (adenosine triphosphate) production. Comet assay showed less brain DNA (deoxyribonucleic acid) damage in rats protected with pomegranate extract. The present study showed, for the first time, that pre-administration of pomegranate extract to rats, can offer a significant dose-dependent neuroprotective activity against cerebral I/R brain injury and DNA damage via antioxidant, anti-inflammatory, anti-apoptotic and ATP-replenishing effects. Copyright © 2014 Elsevier Inc

  5. Gaseous hydrogen sulfide protects against myocardial ischemia-reperfusion injury in mice partially independent from hypometabolism.

    Pauline M Snijder

    Full Text Available BACKGROUND: Ischemia-reperfusion injury (IRI is a major cause of cardiac damage following various pathological processes. Gaseous hydrogen sulfide (H2S is protective during IRI by inducing a hypometabolic state in mice which is associated with anti-apoptotic, anti-inflammatory and antioxidant properties. We investigated whether gaseous H2S administration is protective in cardiac IRI and whether non-hypometabolic concentrations of H2S have similar protective properties. METHODS: Male C57BL/6 mice received a 0, 10, or 100 ppm H2S-N2 mixture starting 30 minutes prior to ischemia until 5 minutes pre-reperfusion. IRI was inflicted by temporary ligation of the left coronary artery for 30 minutes. High-resolution respirometry equipment was used to assess CO2-production and blood pressure was measured using internal transmitters. The effects of H2S were assessed by histological and molecular analysis. RESULTS: Treatment with 100 ppm H2S decreased CO2-production by 72%, blood pressure by 14% and heart rate by 25%, while treatment with 10 ppm H2S had no effects. At day 1 of reperfusion 10 ppm H2S showed no effect on necrosis, while treatment with 100 ppm H2S reduced necrosis by 62% (p<0.05. Seven days post-reperfusion, both 10 ppm (p<0.01 and 100 ppm (p<0.05 H2S showed a reduction in fibrosis compared to IRI animals. Both 10 ppm and 100 ppm H2S reduced granulocyte-influx by 43% (p<0.05 and 60% (p<0.001, respectively. At 7 days post-reperfusion both 10 and 100 ppm H2S reduced expression of fibronectin by 63% (p<0.05 and 67% (p<0.01 and ANP by 84% and 63% (p<0.05, respectively. CONCLUSIONS: Gaseous administration of H2S is protective when administered during a cardiac ischemic insult. Although hypometabolism is restricted to small animals, we now showed that low non-hypometabolic concentrations of H2S also have protective properties in IRI. Since IRI is a frequent cause of myocardial damage during percutaneous coronary intervention and cardiac

  6. Effects of Human Umbilical Cord Mesenchymal Stem Cells on Renal Ischaemia-reperfusion Injury in Rats

    Zhenyu Qiu

    2014-08-01

    Full Text Available Objective This study aims to observe the function of umbilical cord-mesenchymal stem cells (UC-MSCs labelled with enhanced green fluorescent protein (eGFP in the repair of renal ischaemia-reperfusion (I/R injury, to determine the effects on inflammatory cascade in an established rat model and to explore possible pathogenesis. Materials and Methods Sixty rats were randomly divided into three groups: the sham-operated, I/R and UC-MSC treatment groups. All rats underwent right nephrectomy. Ischaemia was induced in the left kidney by occlusion of the renal artery and vein for 1hour, followed by reperfusion for 24 hours or 48 hours. Kidney samples were collected to observe morphological changes. Immunohistochemistry was performed to assess the expression of intercellular adhesion molecule 1 (ICAM-1 in the renal tissue sample, as well as the number of infiltrating polymorphonuclear neutrophils (PMNLs and UC-MSCs with positive eGFP. Results Renal histopathological damages and the expression of ICAM-1 and PMNL increased significantly in the I/R group compared with those in the sham-operated group, whereas the damages were less conspicuous in the UC-MSC treatment group. Conclusions Renal ICAM-1, which mediated PMNL infiltration and contributed to renal damage, was significantly up-regulated in the I/R group. UC-MSCs were identified to inhibit these pathological processes and protect the kidney from I/R injury.

  7. Novel monohydroxamate drugs attenuate myocardial reperfusion-induced arrhythmias

    Collis, C S; Rice-Evans, C; Davies, Michael Jonathan

    1996-01-01

    the first 5 min of reperfusion were quantified. Drugs (all at 150 microM) were introduced during the last 2 min of ischaemia and remained throughout reperfusion. Although the monohydroxamate- and desferrioxamine-treated hearts showed a reduction in the incidence of ventricular tachycardia and fibrillation...

  8. Effects of Intestinal Ischaemia-Reperfusion Injury and Splenectomy ...

    The rats were splenectomized and then subjected to either 20minutes or one hour of superior mesenteric artery and collateral supply ischemia and one hour of reperfusion. Control rats were subjected to either 20minutes or one hour of ischemia and one hour of reperfusion only. Blood samples were collected before and ...

  9. Effect Of Ischemia-Reperfusion On Healing In Intestinal Anastomosis ...

    The effect of reperfusion injury on the healing of intestinal anastomotic wound directly subjected to ischemia-reperfusion stress was investigated in dogs. Three groups of dogs were utilized for the study. In group A (Control) cranial mesenteric artery and collateral blood supply were isolated but not occluded. In groups B and ...

  10. Milrinone-induced postconditioning reduces hepatic ischemia-reperfusion injury in rats: the roles of phosphatidylinositol 3-kinase and nitric oxide.

    Toyoda, Tomomi; Tosaka, Shinya; Tosaka, Reiko; Maekawa, Takuji; Cho, Sungsam; Eguchi, Susumu; Nakashima, Masahiro; Sumikawa, Koji

    2014-01-01

    Ischemic postconditioning (PostC) protects the liver against ischemia-reperfusion (IR) injury. Milrinone, a phosphodiesterase 3 inhibitor, has been reported to exhibit preconditioning properties against hepatic IR injury; however, its PostC properties remain unknown. This study investigated whether milrinone has PostC properties against hepatic IR injury and the roles of phosphatidylinositol 3-kinase (PI3K) and nitric oxide synthase (NOS). Male Wistar rats were separated into six groups: (1) group S: animals that underwent sham operation without ischemia, (2) group C: ischemia followed by reperfusion with no other intervention, (3) group M: milrinone administered immediately after reperfusion, (4) group MW: wortmannin, a PI3K inhibitor, injected before milrinone administration, (5) group MN: l-NAME, a NOS inhibitor, injected before milrinone administration, and (6) group MD, milrinone administered 30 min after reperfusion. Except for group S, all groups underwent 1 h of warm ischemia of median and left lateral lobes, followed by 5 h of reperfusion. Biochemical liver function analysis and histologic examination were performed. Serum aspartate aminotransferase, alanine aminotransferase, and lactic dehydrogenase levels, histologic damage scores, and apoptotic rate in group M were significantly lower than those in group C. The inhibition of PI3K or NOS prevented this protective effect. Milrinone administered 30 min after reperfusion did not show obvious protective effects. Milrinone-induced PostC protects against hepatic IR injury when it is administered immediately after reperfusion, and PI3K and NOS may play an important role in this protective effect. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Bilirubin nanoparticle preconditioning protects against hepatic ischemia-reperfusion injury.

    Kim, Jin Yong; Lee, Dong Yun; Kang, Sukmo; Miao, Wenjun; Kim, Hyungjun; Lee, Yonghyun; Jon, Sangyong

    2017-07-01

    Hepatic ischemia-reperfusion injury (IRI) remains a major concern in liver transplantation and resection, despite continuing efforts to prevent it. Accumulating evidence suggests that bilirubin possesses antioxidant, anti-inflammatory and anti-apoptotic properties. However, despite obvious potential health benefits of bilirubin, its clinical applications are limited by its poor solubility. We recently developed bilirubin nanoparticles (BRNPs) consisting of polyethylene glycol (PEG)-conjugated bilirubin. Here, we sought to investigate whether BRNPs protect against IRI in the liver by preventing oxidative stress. BRNPs exerted potent antioxidant and anti-apoptotic activity in primary hepatocytes exposed to hydrogen peroxide, a precursor of reactive oxygen species (ROS). In a model of hepatic IRI in mice, BRNP preconditioning exerted profound protective effects against hepatocellular injury by reducing oxidative stress, pro-inflammatory cytokine production, and recruitment of neutrophils. They also preferentially accumulated in IRI-induced inflammatory lesions. Collectively, our findings indicate that BRNP preconditioning provides a simple and safe approach that can be easily monitored in the blood like endogenous bilirubin, and could be a promising strategy to protect against IRI in a clinical setting. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Ambient oxygen promotes tumorigenesis.

    Ho Joong Sung

    2011-05-01

    Full Text Available Oxygen serves as an essential factor for oxidative stress, and it has been shown to be a mutagen in bacteria. While it is well established that ambient oxygen can also cause genomic instability in cultured mammalian cells, its effect on de novo tumorigenesis at the organismal level is unclear. Herein, by decreasing ambient oxygen exposure, we report a ∼50% increase in the median tumor-free survival time of p53-/- mice. In the thymus, reducing oxygen exposure decreased the levels of oxidative DNA damage and RAG recombinase, both of which are known to promote lymphomagenesis in p53-/- mice. Oxygen is further shown to be associated with genomic instability in two additional cancer models involving the APC tumor suppressor gene and chemical carcinogenesis. Together, these observations represent the first report directly testing the effect of ambient oxygen on de novo tumorigenesis and provide important physiologic evidence demonstrating its critical role in increasing genomic instability in vivo.

  13. R56865 IS ANTIFIBRILLATORY IN REPERFUSED ISCHEMIC GUINEA-PIG HEARTS, EVEN WHEN GIVEN ONLY DURING REPERFUSION

    SCHEUFLER, E; MOZES, A; GUTTMANN, [No Value; WILFFERT, B

    R56865 was previously characterized as an inhibitor of Na and Ca overload that has beneficial effects during ischemia and reperfusion. An isolated guinea-pig heart preparation was subjected to 60 minutes of ischemia and 60 minutes of reperfusion. R56865 was given before ischemia and with the onset

  14. Effects of Laser Printer–Emitted Engineered Nanoparticles on Cytotoxicity, Chemokine Expression, Reactive Oxygen Species, DNA Methylation, and DNA Damage: A Comprehensive in Vitro Analysis in Human Small Airway Epithelial Cells, Macrophages, and Lymphoblasts

    Pirela, Sandra V.; Miousse, Isabelle R.; Lu, Xiaoyan; Castranova, Vincent; Thomas, Treye; Qian, Yong; Bello, Dhimiter; Kobzik, Lester; Koturbash, Igor; Demokritou, Philip

    2015-01-01

    Background Engineered nanomaterials (ENMs) incorporated into toner formulations of printing equipment become airborne during consumer use. Although information on the complex physicochemical and toxicological properties of both toner powders and printer-emitted particles (PEPs) continues to grow, most toxicological studies have not used the actual PEPs but rather have primarily used raw toner powders, which are not representative of current exposures experienced at the consumer level during printing. Objectives We assessed the biological responses of a panel of human cell lines to PEPs. Methods Three physiologically relevant cell lines—small airway epithelial cells (SAECs), macrophages (THP-1 cells), and lymphoblasts (TK6 cells)—were exposed to PEPs at a wide range of doses (0.5–100 μg/mL) corresponding to human inhalation exposure durations at the consumer level of 8 hr or more. Following treatment, toxicological parameters reflecting distinct mechanisms were evaluated. Results PEPs caused significant membrane integrity damage, an increase in reactive oxygen species (ROS) production, and an increase in pro-inflammatory cytokine release in different cell lines at doses equivalent to exposure durations from 7.8 to 1,500 hr. Furthermore, there were differences in methylation patterns that, although not statistically significant, demonstrate the potential effects of PEPs on the overall epigenome following exposure. Conclusions The in vitro findings obtained in this study suggest that laser printer–emitted engineered nanoparticles may be deleterious to lung cells and provide preliminary evidence of epigenetic modifications that might translate to pulmonary disorders. Citation Pirela SV, Miousse IR, Lu X, Castranova V, Thomas T, Qian Y, Bello D, Kobzik L, Koturbash I, Demokritou P. 2016. Effects of laser printer–emitted engineered nanoparticles on cytotoxicity, chemokine expression, reactive oxygen species, DNA methylation, and DNA damage: a comprehensive in

  15. Ischaemia-reperfusion injury: a major protagonist in kidney transplantation.

    Ponticelli, Claudio

    2014-06-01

    Ischaemia-reperfusion injury (IRI) is a frequent event in kidney transplantation, particularly when the kidney comes from a deceased donor. The brain death is usually associated with generalized ischaemia due to a hyperactivity of the sympathetic system. In spite of this, most donors have profound hypotension and require administration of vasoconstrictor agents. Warm ischaemia after kidney vessels clamping and the cold ischaemia after refrigeration also reduce oxygen and nutrients supply to tissues. The reperfusion further aggravates the state of oxidation and inflammation created by ischaemia. IRI first attacks endothelial cells and tubular epithelial cells. The lesions may be so severe that they lead to acute kidney injury (AKI) and delayed graft function (DGF), which can impair the graft survival. The unfavourable impact of DGF is worse when DGF is associated with acute rejection. Another consequence of IRI is the activation of the innate immunity. Danger signals released by dying cells alarm Toll-like receptors that, through adapter molecules and a chain of kinases, transmit the signal to transcription factors which encode the genes regulating inflammatory cells and mediators. In the inflammatory environment, dendritic cells (DCs) intercept the antigen, migrate to lymph nodes and present the antigen to immunocompetent cells, so activating the adaptive immunity and favouring rejection. Attempts to prevent IRI include optimal management of donor and recipient. Calcium-channel blockers, l-arginine and N-acetylcysteine could obtain a small reduction in the incidence of post-transplant DGF. Fenoldopam, Atrial Natriuretic Peptide, Brain Natriuretic Peptide and Dopamine proved to be helpful in reducing the risk of AKI in experimental models, but there is no controlled evidence that these agents may be of benefit in preventing DGF in kidney transplant recipients. Other antioxidants have been successfully used in experimental models of AKI but only a few studies of poor

  16. Protection of Ischemic and Reperfused Rat Heart by Aqueous Extract of Urtica Dioica

    D Shackebaei

    2010-09-01

    Full Text Available Background: Urtica dioica (U.D has widely been used in traditional medicine for its hypotensive and vasodilatory effects. The objective of this study was to clarify the effects of aqueous extract of Urtica dioica on isolated ischemia- reperfused heart.Methods: The heart of male wistar rats were isolated and perfused according to langendorff method. In the control group (n = 13 the hearts were subjected to three steps of stabilization (30 min, normothermic global ischemia (40 min and reperfusion (45 min. In addition, before and after ischemia, the aqueous extract of U.D (200 mg/ml was added to perfusion solution in the test group (n=14. Different cardiac variables including left ventricular pressure, heart rate and coronary flow were measured and rate pressure product was calculated.Results: Results showed that left ventricular pressure (59.11±4.7 and rate pressure product (13680±1136 in 45th minute of reperfusion in the test group were significantly (P=0.0187 and 0.0321 respectively greater than the control group (39.1±6.0, 9480±1480 respectively. These findings indicated decreased cardiac damage following ischemia in the test group, compared with that of control group.Conclusion: Results of the present study showed that the aqueous extract of U.D, increased the tolerance of isolated rat hearts against ischemic damage. This effect can be explained by potent antioxidant activity of the U.D extract, suggesting its clinical use in ischemic heart disease.

  17. Effect of baicalin on toll-like receptor 4-mediated ischemia/reperfusion inflammatory responses in alcoholic fatty liver condition

    Kim, Seok-Joo; Lee, Sun-Mee

    2012-01-01

    Alcoholic fatty liver is susceptible to secondary stresses such as ischemia/reperfusion (I/R). Baicalin is an active component extracted from Scutellaria baicalensis, which is widely used in herbal preparations for treatment of hepatic diseases and inflammatory disorders. This study evaluated the potential beneficial effect of baicalin on I/R injury in alcoholic fatty liver. Rats were fed an alcohol liquid diet or a control isocaloric diet for 5 weeks, and then subjected to 60 min of hepatic ischemia and 5 h of reperfusion. Baicalin (200 mg/kg) was intraperitoneally administered 24 and 1 h before ischemia. After reperfusion, baicalin attenuated the increases in serum alanine aminotransferase activity, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) levels in alcoholic fatty liver. The increased levels of TNF-α and IL-6 mRNA expression and inducible nitric oxide synthase and cyclooxygenase-2 protein and mRNA expressions increased after reperfusion, which were higher in ethanol-fed animals, were attenuated by baicalin. In ethanol-fed animals, baicalin attenuated the increases in toll-like receptor 4 (TLR4) and myeloid differentiation factor 88 protein expressions and the nuclear translocation of NF-κB after reperfusion. In conclusion, our findings suggest that baicalin ameliorates I/R-induced hepatocellular damage by suppressing TLR4-mediated inflammatory responses in alcoholic fatty liver. -- Highlights: ► Baicalin attenuates hepatic I/R-induced inflammation in alcoholic fatty liver. ► Baicalin downregulates TLR4, MyD88 expression during I/R in alcoholic fatty liver. ► Baicalin attenuates NF-κB nuclear translocation during I/R in alcoholic fatty liver.

  18. Hepatic ischemia and reperfusion injury in the absence of myeloid cell-derived COX-2 in mice.

    Sergio Duarte

    Full Text Available Cyclooxygenase-2 (COX-2 is a mediator of hepatic ischemia and reperfusion injury (IRI. While both global COX-2 deletion and pharmacologic COX-2 inhibition ameliorate liver IRI, the clinical use of COX-2 inhibitors has been linked to increased risks of heart attack and stroke. Therefore, a better understanding of the role of COX-2 in different cell types may lead to improved therapeutic strategies for hepatic IRI. Macrophages of myeloid origin are currently considered to be important sources of the COX-2 in damaged livers. Here, we used a Cox-2flox conditional knockout mouse (COX-2-M/-M to examine the function of COX-2 expression in myeloid cells during liver IRI. COX-2-M/-M mice and their WT control littermates were subjected to partial liver ischemia followed by reperfusion. COX-2-M/-M macrophages did not express COX-2 upon lipopolysaccharide stimulation and COX-2-M/-M livers showed reduced levels of COX-2 protein post-IRI. Nevertheless, selective deletion of myeloid cell-derived COX-2 failed to ameliorate liver IRI; serum transaminases and histology were comparable in both COX-2-M/-M and WT mice. COX-2-M/-M livers, like WT livers, developed extensive necrosis, vascular congestion, leukocyte infiltration and matrix metalloproteinase-9 (MMP-9 expression post-reperfusion. In addition, myeloid COX-2 deletion led to a transient increase in IL-6 levels after hepatic reperfusion, when compared to controls. Administration of celecoxib, a selective COX-2 inhibitor, resulted in significantly improved liver function and histology in both COX-2-M/-M and WT mice post-reperfusion, providing evidence that COX-2-mediated liver IRI is caused by COX-2 derived from a source(s other than myeloid cells. In conclusion, these results support the view that myeloid COX-2, including myeloid-macrophage COX-2, is not responsible for the hepatic IRI phenotype.

  19. Increased expression of IRE1α and stress-related signal transduction proteins in ischemia-reperfusion injured retina

    Natsuyo Hata

    2008-08-01

    Full Text Available Natsuyo Hata1, Toshiyuki Oshitari1,2, Akiko Yokoyama1,3, Yoshinori Mitamura1, Shuichi Yamamoto11Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Chuo-ku, Chiba, Japan; 2Department of Ophthalmology, Kimitsu Central Hospital, Kisarazu City, Chiba, Japan; 3Department of Ophthalmology, Inoue Memorial Hospital, Chuo-ku, Chiba, JapanAbstract: The purpose of this study was to determine whether the expression of ER stress-related factors IRE1α, apoptosis signal-regulating kinase 1 (ASK1, SAPK/ERK kinase 1 (SEK1 and c-Jun N-terminal kinase (JNK is associated with the damaged retinal neurons induced by ischemia-reperfusion injury. After 60 minutes of ischemia, the rat retinas were reperfused, and retinas were isolated and fixed after 6, 9, 12, 18, and 24 hours, and 2, 5, and 9 days of reperfusion. Cryosections were immunostained with Fluoro-Jade B, a degenerating neuron marker to label degenerating neurons. Semi-quantitative analysis of the expression of IRE1α, ASK1, SEK1, and JNK were performed in both control and ischemic retinas. In ischemic retinas, the intensities of IRE1α immunoreactivity in the ganglion cell layer (GCL were significantly higher than in the control retinas. In ischemic retinas, the numbers of SEK1-, ASK1-, and JNK-positive cells were significantly increased in the GCL compared to those in the control retinas. In addition, the cells that were positive for SEK1-, ASK1-, and JNK were also positive for Fluoro-Jade B-positive cells. These results indicate that the increased expression of ER stress-related factors was, in part, associated with the retinal neuronal abnormalities after ischemia-reperfusion injury in rat retinas.Keywords: endoplasmic reticulum, IRE1α, apoptosis signal-regulating kinase 1, SAPK/ERK kinase 1, c-Jun N-terminal kinase, Fluoro-Jade B, ischemia-reperfusion injury

  20. Evaluation of the Effects of Atorvastatin and Ischemic Postconditioning Preventing on the Ischemia and Reperfusion Injury: Experimental Study in Rats

    Henrique Budib Dorsa Pontes

    Full Text Available Abstract Introduction: Reperfusion injury leads to systemic morphological and functional pathological alterations. Some techniques are already estabilished to attenuate the damage induced by reperfusion. Ischemic preconditioning is one of the standard procedures. In the last 20 years, several experimental trials demonstrated that the ischemic postconditioning presents similar effectiveness. Recently experimental trials demonstrated that statins could be used as pharmacological preconditioning. Methods: 41 Wistar rats (Rattus norvegicus albinus were distributed in 5 groups: Ischemia and Reperfusion (A, Ischemic Postconditioning (B, Statin (C, Ischemic Postconditioning + Statins (D and SHAM (E. After euthanasia, lungs, liver, kidneys and ileum were resected and submitted to histopathological analysis. Results: The average of lung parenchymal injury was A=3.6, B=1.6, C=1.2, D=1.2, E=1 (P=0.0029. The average of liver parenchymal injury was A=3, B=1.5, C=1.2, D=1.2, E = 0 (P<0.0001. The average of renal parenchymal injury was A=4, B=2.44, C=1.22, D=1.11, E=1 (P<0.0001. The average of intestinal parenchymal injury was A=2, B=0.66, C=0, D=0, E=0 (P=0.0006. The results were submitted to statistics applying Kruskal-Wallis test, estabilishing level of significance P<0.05. Conclusion: Groups submitted to ischemic postconditioning, to pre-treatment with statins and both methods associated demonstrated less remote reperfusion injuries, compared to the group submitted to ischemia and reperfusion without protection.

  1. Let-7i attenuates human brain microvascular endothelial cell damage in oxygen glucose deprivation model by decreasing toll-like receptor 4 expression.

    Xiang, Wei; Tian, Canhui; Peng, Shunli; Zhou, Liang; Pan, Suyue; Deng, Zhen

    2017-11-04

    The let-7 family of microRNAs (miRNAs) plays an important role on endothelial cell function. However, there have been few studies on their role under ischemic conditions. In this study, we demonstrate that let-7i, belonging to the let-7 family, rescues human brain microvascular endothelial cells (HBMECs) in an oxygen-glucose deprivation (OGD) model. Our data show that the expression of let-7 family miRNAs was downregulated after OGD. Overexpression of let-7i significantly alleviated cell death and improved survival of OGD-treated HBMECs. Let-7i also protected permeability in an in vitro blood brain barrier (BBB) model. Further, let-7i downregulated the expression of toll-like receptor 4 (TLR4), an inflammation trigger. Moreover, overexpression of let-7i decreased matrix metallopeptidase 9 (MMP9) and inducible nitric oxide synthase (iNOS) expression under OGD. Upon silencing TLR4 expression in HBMECs, the anti-inflammatory effect of let-7i was abolished. Our research suggests that let-7i promotes OGD-induced inflammation via downregulating TLR4 expression. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Prophylactic Ozone Administration Reduces Intestinal Mucosa Injury Induced by Intestinal Ischemia-Reperfusion in the Rat

    Ozkan Onal

    2015-01-01

    Full Text Available Objectives. Intestinal ischemia-reperfusion injury is associated with mucosal damage and has a high rate of mortality. Various beneficial effects of ozone have been shown. The aim of the present study was to show the effects of ozone in ischemia reperfusion model in intestine. Material and Method. Twenty eight Wistar rats were randomized into four groups with seven rats in each group. Control group was administered serum physiologic (SF intraperitoneally (ip for five days. Ozone group was administered 1 mg/kg ozone ip for five days. Ischemia Reperfusion (IR group underwent superior mesenteric artery occlusion for one hour and then reperfusion for two hours. Ozone + IR group was administered 1 mg/kg ozone ip for five days and at sixth day IR model was applied. Rats were anesthetized with ketamine∖xyzlazine and their intracardiac blood was drawn completely and they were sacrificed. Intestinal tissue samples were examined under light microscope. Levels of superoxide dismutase (SOD, catalase (CAT, glutathioneperoxidase (GSH-Px, malondyaldehide (MDA, and protein carbonyl (PCO were analyzed in tissue samples. Total oxidant status (TOS, and total antioxidant capacity (TAC were analyzed in blood samples. Data were evaluated statistically by Kruskal Wallis test. Results. In the ozone administered group, degree of intestinal injury was not different from the control group. IR caused an increase in intestinal injury score. The intestinal epithelium maintained its integrity and decrease in intestinal injury score was detected in Ozone + IR group. SOD, GSH-Px, and CAT values were high in ozone group and low in IR. TOS parameter was highest in the IR group and the TAC parameter was highest in the ozone group and lowest in the IR group. Conclusion. In the present study, IR model caused an increase in intestinal injury.In the present study, ozone administration had an effect improving IR associated tissue injury. In the present study, ozone therapy

  3. Multi-modal assessment of neurovascular coupling during cerebral ischaemia and reperfusion using remote middle cerebral artery occlusion

    Sutherland, Brad A; Fordsmann, Jonas C; Martin, Chris

    2017-01-01

    . Male Wistar rats were subjected to remote middle cerebral artery occlusion, where a long filament was advanced intraluminally through a guide cannula in the common carotid artery. Transcallosal stimulation evoked increases in blood flow, tissue oxygenation and neuronal activity, which were diminished...... that neurovascular dysfunction was not sustained. These data show for the first time that the rat remote middle cerebral artery occlusion model coupled with transcallosal stimulation provides a novel method for continuous assessment of hyperacute neurovascular coupling changes during ischaemia and reperfusion......Hyperacute changes in cerebral blood flow during cerebral ischaemia and reperfusion are important determinants of injury. Cerebral blood flow is regulated by neurovascular coupling, and disruption of neurovascular coupling contributes to brain plasticity and repair problems. However, it is unknown...

  4. 13-Methyltetradecanoic acid mitigates cerebral ischemia/reperfusion injury

    Juan Yu

    2016-01-01

    Full Text Available 13-Methyltetradecanoic acid can stabilize cell membrane and have anti-inflammatory, antioxidant and anti-apoptotic effects. Previous studies mainly focused on peripheral nerve injury, but seldom on the central nervous system. We investigated whether these properties of 13-methyltetradecanoic acid have a neuroprotective effect on focal cerebral ischemia/reperfusion injury, and detected the expression of basic fibroblast growth factor and vascular endothelial growth factor. This study established rat models of middle cerebral artery occlusion/reperfusion injury by ischemia for 2 hours and reperfusion for 24 hours. At the beginning of reperfusion, 13-methyltetradecanoic acid 10, 40 or 80 mg/kg was injected into the tail vein. Results found that various doses of 13-methyltetradecanoic acid effectively reduced infarct volume, mitigate cerebral edema, and increased the mRNA and protein expression of basic fibroblast growth factor and vascular endothelial growth factor at 24 hours of reperfusion. The effect was most significant in the 13-methyltetradecanoic acid 40 and 80 mg/kg groups. The findings suggest that 13-methyltetradecanoic acid can relieve focal ischemia/reperfusion injury immediately after reperfusion, stimulate the upregulation of basic fibroblast growth factor and vascular endothelial growth factor to exert neuroprotective effects.

  5. Protection of Liver as a Remote Organ after Renal Ischemia-Reperfusion Injury by Renal Ischemic Postconditioning

    Behjat Seifi

    2014-01-01

    Full Text Available This study was designed to investigate the protective effects of local renal ischemic postconditioning (POC on liver damage after renal ischemia-reperfusion (IR injury. Male rats were divided into three groups  (n=8. They underwent a right nephrectomy before induction of 45 minutes of left kidney ischemia or sham operation. POC was performed by four cycles of 10 seconds of ischemia and 10 seconds of reperfusion just at the beginning of 24 hours of reperfusion. Then blood and liver samples were collected to measure serum aspartate aminotransferase (AST, alanine aminotransferase (ALT, and liver oxidative stress parameters including superoxide dismutase (SOD activity and malondialdehyde (MDA level. Renal IR caused a significant increase in liver functional indices as demonstrated by increased serum AST and ALT compared to sham group. These parameters reduced significantly in POC group compared to IR group. Liver MDA levels increased and SOD activity decreased in IR group compared to sham group. Induction of POC reduced the elevated liver MDA levels and increased the reduced liver SOD activity. These results revealed that renal IR injury causes liver damage as a remote organ and POC protects liver from renal IR injury by a modification in the hepatic oxidative stress status.

  6. Relation between reperfusion and hemorrhagic transformation in acute ischemic stroke

    Horsch, Alexander D. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Rijnstate Hospital, Department of Radiology, Arnhem (Netherlands); Dankbaar, Jan Willem; Niesten, Joris M.; Seeters, Tom van; Schaaf, Irene C. van der; Velthuis, Birgitta K. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Graaf, Yolanda van der [Julius Center for Health Sciences and Primary Care, Utrecht (Netherlands); Kappelle, L.J. [University Medical Center, Department of Neurology, Utrecht Stroke Center, Utrecht (Netherlands); Collaboration: DUST investigators

    2015-12-15

    Intravenous recombinant tissue plasminogen activator (IV-rtPA) is given in acute ischemic stroke patients to achieve reperfusion. Hemorrhagic transformation (HT) is a serious complication of IV-rtPA treatment and related to blood-brain barrier (BBB) injury. It is unclear whether HT occurs secondary to reperfusion in combination with ischemic BBB injury or is caused by the negative effect of IV-rtPA on BBB integrity. The aim of this study was to establish the association between reperfusion and the occurrence of HT. From the DUST study, patients were selected with admission and follow-up non-contrast CT (NCCT) and CT perfusion (CTP) imaging, and a perfusion deficit in the middle cerebral artery territory on admission. Reperfusion was categorized qualitatively as reperfusion or no-reperfusion by visual comparison of admission and follow-up CTP. Occurrence of HT was assessed on follow-up NCCT. The association between reperfusion and occurrence of HT on follow-up was estimated by calculating odds ratios (ORs) and 95 % confidence intervals (CIs) with additional stratification for IV-rtPA treatment. Inclusion criteria were met in 299 patients. There was no significant association between reperfusion and HT (OR 1.2 95%CI 0.5-3.1). In patients treated with IV-rtPA (n = 203), the OR was 1.3 (95%CI 0.4-4.0), and in patients not treated with IV-rtPA (n = 96), the OR was 0.8 (95%CI 0.1-4.5). HT occurred in 14 % of the IV-rtPA patients and in 7 % of patients without IV-rtPA (95%CI of difference -1 to 14 %). Our results suggest that the increased risk of HT after acute ischemic stroke treatment is not dependent on the reperfusion status. (orig.)

  7. The Effect of Etoricoxib on Hepatic Ischemia-Reperfusion Injury in Rats

    Celalettin Semih Kunak

    2015-01-01

    Full Text Available Ischemia-reperfusion (I/R damage is known to be a pathological process which continues with the increase of oxidants and expands with the inflammatory response. There is not any study about protective effect of etoricoxib on the liver I/R damage in literature. Objective. This study investigates the effect of etoricoxib on oxidative stress induced by I/R of the rat liver. Material and Methods. Experimental animals were divided into four groups as liver I/R control (LIRC, 50 mg/kg etoricoxib + liver I/R (ETO-50, 100 mg/kg etoricoxib + liver I/R (ETO-100, and healthy group (HG. ETO-50 and ETO-100 groups were administered etoricoxib, while LIRC and HG groups were orally given distilled water by gavage. Hepatic artery was clamped for one hour to provide ischemia, and then reperfusion was provided for 6 hours. Oxidant, antioxidant, and COX-2 gene expressions were studied in the liver tissues. ALT and AST were measured. Results. Etoricoxib in 50 and 100 mg/kg doses changed the levels of oxidant/antioxidant parameters such as MDA, MPO, tGSH, GSHRd, GST, SOD, NO, and 8-OH/Gua in favour of antioxidants. Furthermore, etoricoxib prevented increase of COX-2 gene expression and ALT and AST levels. This important protective effect of etoricoxib on the rat liver I/R can be tested in the clinical setting.

  8. Riboflavin (vitamin B-2) reduces hepatocellular injury following liver ischaemia and reperfusion in mice.

    Sanches, Sheila Cristina; Ramalho, Leandra Naira Z; Mendes-Braz, Mariana; Terra, Vânia Aparecida; Cecchini, Rubens; Augusto, Marlei Josiele; Ramalho, Fernando Silva

    2014-05-01

    Riboflavin has been shown to exhibit anti-inflammatory and antioxidant properties in the settings of experimental sepsis and ischaemia/reperfusion (I/R) injury. We investigated the effect of riboflavin on normothermic liver I/R injury. Mice were submitted to 60 min of ischaemia plus saline or riboflavin treatment (30 μmoles/kg BW) followed by 6 h of reperfusion. Hepatocellular injury was evaluated by aminotransferase levels, reduced glutathione (GSH) content and the histological damage score. Hepatic neutrophil accumulation was assessed using the naphthol method and by measuring myeloperoxidase activity. Hepatic oxidative/nitrosative stress was estimated by immunohistochemistry. Liver endothelial and inducible nitric oxide synthase (eNOS/iNOS) and nitric oxide (NO) amounts were assessed by immunoblotting and a chemiluminescence assay. Riboflavin significantly reduced serum and histological parameters of hepatocellular damage, neutrophil infiltration and oxidative/nitrosative stress. Furthermore, riboflavin infusion partially recovered hepatic GSH reserves and decreased the liver contents of eNOS/iNOS and NO. These data indicate that riboflavin exerts antioxidant and anti-inflammatory effects in the ischaemic liver, protecting hepatocytes against I/R injury. The mechanism of these effects appears to be related to the intrinsic antioxidant potential of riboflavin/dihydroriboflavin and to reduced hepatic expression of eNOS/iNOS and reduced NO levels, culminating in attenuation of oxidative/nitrosative stress and the acute inflammatory response. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Polyethylene glycol rinse solution: An effective way to prevent ischemia-reperfusion injury

    Zaouali, Mohamed Amine; Bejaoui, Mohamed; Calvo, Maria; Folch-Puy, Emma; Pantazi, Eirini; Pasut, Gianfranco; Rimola, Antoni; Ben Abdennebi, Hassen; Adam, René; Roselló-Catafau, Joan

    2014-01-01

    AIM: To test whether a new rinse solution containing polyethylene glycol 35 (PEG-35) could prevent ischemia-reperfusion injury (IRI) in liver grafts. METHODS: Sprague-Dawley rat livers were stored in University of Wisconsin preservation solution and then washed with different rinse solutions (Ringer’s lactate solution and a new rinse solution enriched with PEG-35 at either 1 or 5 g/L) before ex vivo perfusion with Krebs-Heinseleit buffer solution. We assessed the following: liver injury (transaminase levels), mitochondrial damage (glutamate dehydrogenase activity), liver function (bile output and vascular resistance), oxidative stress (malondialdehyde), nitric oxide, liver autophagy (Beclin-1 and LCB3) and cytoskeleton integrity (filament and globular actin fraction); as well as levels of metalloproteinases (MMP2 and MMP9), adenosine monophosphate-activated protein kinase (AMPK), heat shock protein 70 (HSP70) and heme oxygenase 1 (HO-1). RESULTS: When we used the PEG-35 rinse solution, reduced hepatic injury and improved liver function were noted after reperfusion. The PEG-35 rinse solution prevented oxidative stress, mitochondrial damage, and liver autophagy. Further, it increased the expression of cytoprotective heat shock proteins such as HO-1 and HSP70, activated AMPK, and contributed to the restoration of cytoskeleton integrity after IRI. CONCLUSION: Using the rinse solution containing PEG-35 was effective for decreasing liver graft vulnerability to IRI. PMID:25473175

  10. Different dose-dependent effects of ebselen in sciatic nerve ischemia-reperfusion injury in rats.

    Ozyigit, Filiz; Kucuk, Aysegul; Akcer, Sezer; Tosun, Murat; Kocak, Fatma Emel; Kocak, Cengiz; Kocak, Ahmet; Metineren, Hasan; Genc, Osman

    2015-08-26

    Ebselen is an organoselenium compound which has strong antioxidant and anti-inflammatory effects. We investigated the neuroprotective role of ebselen pretreatment in rats with experimental sciatic nerve ischemia-reperfusion (I/R) injury. Adult male Sprague Dawley rats were divided into four groups (N = 7 in each group). Before sciatic nerve I/R was induced, ebselen was injected intraperitoneally at doses of 15 and 30 mg/kg. After a 2 h ischemia and a 3 h reperfusion period, sciatic nerve tissues were excised. Tissue levels of malondialdehyde (MDA) and nitric oxide (NO), and activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) were measured. Sciatic nerve tissues were also examined histopathologically. The 15 mg/kg dose of ebselen reduced sciatic nerve damage and apoptosis (pebselen. Conversely, the 30 mg/kg dose of ebselen increased sciatic nerve damage, apoptosis, iNOS positive cells (pebselen may cause different effects depending on the dose employed. Ebselen may be protective against sciatic nerve I/R injury via antioxidant and antiapoptotic activities at a 15 mg/kg dose, conversely higher doses may cause detrimental effects.

  11. Isoflurane administration before ischemia and during reperfusion attenuates ischemia/reperfusion-induced injury of isolated rabbit lungs.

    Liu, R; Ishibe, Y; Ueda, M; Hang, Y

    1999-09-01

    To investigate the effects of isoflurane on ischemia/ reperfusion (IR)-induced lung injury, we administered isoflurane before ischemia or during reperfusion. Isolated rabbit lungs were divided into the following groups: control (n = 6), perfused and ventilated for 120 min without ischemia; ISO-control (n = 6), 1 minimum alveolar anesthetic concentration (MAC) isoflurane was administered for 30 min before 120 min continuous perfusion; IR (n = 6), ischemia for 60 min, followed by 60 min reperfusion; IR-ISO1 and IR-ISO2, ischemia followed by reperfusion and 1 MAC (n = 6) or 2 MAC (n = 6) isoflurane for 60 min; ISO-IR (n = 6), 1 MAC isoflurane was administered for 30 min before ischemia, followed by IR. During these maneuvers, we measured total pulmonary vascular resistance (Rt), coefficient of filtration (Kfc), and lung wet to dry ratio (W/D). The results indicated that administration of isoflurane during reperfusion inhibited an IR-induced increase in Kfc and W/D ratio. Furthermore, isoflurane at 2 MAC, but not 1 MAC, significantly inhibited an IR-induced increase in Rt. The administration of isoflurane before ischemia significantly attenuated the increase in IR-induced Kfc, W/D, and Rt. Our results suggest that the administration of isoflurane before ischemia and during reperfusion protects against ischemia-reperfusion-induced injury in isolated rabbit lungs.

  12. Putative role of ischemic postconditioning in a rat model of limb ischemia and reperfusion: involvement of hypoxia-inducible factor-1α expression

    Wang, T. [Department of Anesthesiology, Shuyang People' s Hospital, JiangSu (China); Zhou, Y.T. [Department of General Surgery, Shuyang People' s Hospital, JiangSu (China); Chen, X.N. [Institute of Pathophysiology, School of Basic Medical Sciences, LanZhou University, Lanzhou, Gansu (China); Zhu, A.X. [Department of Pharmacy, Shuyang People' s Hospital, JiangSu (China)

    2014-07-25

    Hypoxia-inducible factor-1α (HIF-1α) is one of the most potent angiogenic growth factors. It improves angiogenesis and tissue perfusion in ischemic skeletal muscle. In the present study, we tested the hypothesis that ischemic postconditioning is effective for salvaging ischemic skeletal muscle resulting from limb ischemia-reperfusion injury, and that the mechanism involves expression of HIF-1α. Wistar rats were randomly divided into three groups (n=36 each): sham-operated (group S), hindlimb ischemia-reperfusion (group IR), and ischemic postconditioning (group IPO). Each group was divided into subgroups (n=6) according to reperfusion time: immediate (0 h, T{sub 0}), 1 h (T{sub 1}), 3 h (T{sub 3}), 6 h (T{sub 6}), 12 h (T{sub 12}), and 24 h (T{sub 24}). In the IPO group, three cycles of 30-s reperfusion and 30-s femoral aortic reocclusion were carried out before reperfusion. At all reperfusion times (T{sub 0}-T{sub 24}), serum creatine kinase (CK) and lactate dehydrogenase (LDH) activities, as well as interleukin (IL)-6, IL-10, and tumor necrosis factor-α (TNF-α) concentrations, were measured in rats after they were killed. Histological and immunohistochemical methods were used to assess the skeletal muscle damage and HIF-1α expression in skeletal muscle ischemia. In groups IR and IPO, serum LDH and CK activities and TNF-α, IL-6, and IL-10 concentrations were all significantly increased compared to group S, and HIF-1α expression was up-regulated (P<0.05 or P<0.01). In group IPO, serum LDH and CK activities and TNF-α and IL-6 concentrations were significantly decreased, IL-10 concentration was increased, HlF-1α expression was down-regulated (P<0.05 or P<0.01), and the pathological changes were reduced compared to group IR. The present study suggests that ischemic postconditioning can reduce skeletal muscle damage caused by limb ischemia-reperfusion and that its mechanisms may be related to the involvement of HlF-1α in the limb ischemia-reperfusion injury

  13. Upregulation of NOX2 and NOX4 Mediated by TGF-β Signaling Pathway Exacerbates Cerebral Ischemia/Reperfusion Oxidative Stress Injury

    Zheng Lou

    2018-04-01

    Full Text Available Background/Aims: Ischemic stroke is still one of the leading debilitating diseases with high morbidity and mortality. NADPH oxidase (NOX-derived reactive oxygen species (ROS play an important role in cerebral ischemia/reperfusion (I/R injury. However, the mechanism underlying the regulation of ROS generation is still not fully elucidated. This study aims to explore the role of transforming growth beta (TGF-β signals in ROS generation. Methods: Sprague–Dawley rats were subjected to I/R injury, and PC-12 cells were challenged by hypoxia/reoxygenation (H/R and/or treated with activin receptor-like kinase (ALK5 inhibitor Sb505124 or siRNA against ALK5. Brain damage was evaluated using neurological scoring, triphenyl tetrazolium chloride staining, hematoxylin and eosin staining, infarct volume measurement, TUNEL staining, and caspase-3 activity measurement. Expression of TGF-β and oxidative stress-related genes was analyzed by real-time polymerase chain reaction and Western blot; NOX activity and ROS level were measured using spectrophotometry and fluorescence microscopy, respectively. Results: I/R contributed to severe brain damage (impaired neurological function, brain infarction, tissue edema, apoptosis, TGF-β signaling activation (upregulation of ALK5, phosphorylation of SMAD2/3 and oxidative stress (upregulation of NOX2/4, rapid release of ROS [oxidative burst]. However, Sb505124 significantly reversed these alterations and protected rats against I/R injury. As in the animal results, H/R also contributed to TGF-β signaling activation and oxidative stress. Likewise, the inhibition of ALK5 or ALK5 knockdown significantly reversed these alterations in PC-12 cells. Other than ALK5 knockdown, ALK5 inhibition had no effect on the expression of ALK5 in PC-12 cells. Conclusions: Our studies demonstrated that TGF-β signaling activation is involved in the regulation of NOX2/NOX4 expression and exacerbates cerebral I/R injury.

  14. Nebivolol and chrysin protect the liver against ischemia/reperfusion-induced injury in rats

    Sayed M. Mizar

    2015-03-01

    Full Text Available Oxidative stress plays a key role in the pathogenesis of hepatic ischemia/reperfusion (I/R-induced injury, one of the leading causes of liver damage post-surgical intervention, trauma and transplantation. This study aimed to evaluate the protective effect of nebivolol and chrysin against I/R-induced liver injury via their vasodilator and antioxidant effects, respectively. Adult male Wister rats received nebivolol (5 mg/kg and/or chrysin (25 mg/kg by oral gavage daily for one week then subjected to ischemia via clamping the portal triad for 30 min then reperfusion for 30 min. Liver function enzymes, alanine transaminase (ALT and aspartate transaminase (AST, as well as hepatic Myeloperoxidase (MPO, total nitrate (NOx, glutathione (GSH and liver malondialdehyde (MDA were measured at the end of the experiment. Liver tissue damage was examined by histopathology. In addition, the expression levels of nitric oxide synthase (NOS subtypes, endothelial (eNOS and inducible (iNOS in liver samples were assessed by Western blotting and confirmed by immunohistochemical analysis. Both chrysin and nebivolol significantly counteracted I/R-induced oxidative stress and tissue damage biomarkers. The combination of these agents caused additive liver protective effect against I/R-induced damage via the up regulation of nitric oxide expression and the suppression of oxidative stress. Chrysin and nebivolol combination showed a promising protective effect against I/R-induced liver injury, at least in part, via decreasing oxidative stress and increasing nitric oxide levels.

  15. Vitamin E deficiency fails to affect myocardial performance during in vivo ischemia-reperfusion.

    Coombes, J S; Powers, S K; Demirel, H A; Hamilton, K L; Jessup, J; Vincent, H K; Shanely, R A

    2000-12-01

    Vitamin E content of cardiac tissue has been proposed to play a major role in the damage caused by myocardial ischemia-reperfusion (I-R). Previous studies using in vitro models have examined vitamin E deficiency and I-R-induced myocardial damage with equivocal results. The purpose of this study was to use an in vivo model of myocardial I-R to determine the effects of vitamin E deficiency on myocardial I-R-induced damage. Female Sprague-Dawley rats (4-mo old) were assigned to either: 1) control diet (CON), or 2) vitamin E deficient diet (VE-DEF). The CON diet was prepared to meet AIN-93M standards, which contains 75 IU vitamin E/kg diet. The VE-DEF diet was the AIN-93M diet prepared with tocopherol stripped corn oil and no vitamin E. Following a 14-week feeding period, significant differences (p CON = 48.2 +/- 3.5; VE-DEF = 12.4 +/- 1.4 micrograms VE/g wet weight). Animals from both experimental groups were subjected to an in vivo I-R protocol consisting of 25 minutes of left coronary artery occlusion followed by 10 minutes of reperfusion. No group differences (p > 0.05) existed in cardiac performance (peak arterial pressure or ventricular work) or the incidence of ventricular arrhythmias during the I-R protocol. VE-DEF animals had significantly higher (p CON animals. These data suggest that although vitamin E deficiency increases oxidative damage resulting from myocardial I-R, it does not affect cardiac performance during the insult.

  16. Protective effect of Urtica dioica L. on renal ischemia/reperfusion injury in rat.

    Sayhan, Mustafa Burak; Kanter, Mehmet; Oguz, Serhat; Erboga, Mustafa

    2012-12-01

    Renal ischemia-reperfusion (I/R) injury may occur after renal transplantation, thoracoabdominal aortic surgery, and renal artery interventions. This study was designed to investigate the effect of Urtica dioica L. (UD), in I/R induced renal injury. A total of 32 male Sprague-Dawley rats were divided into four groups: control, UD alone, I/R and I/R + UD; each group contain 8 animals. A rat model of renal I/R injury was induced by 45-min occlusion of the bilateral renal pedicles and 24-h reperfusion. In the UD group, 3 days before I/R, UD (2 ml/kg/day intraperitoneal) was administered by gastric gavage. All animals were sacrificed at the end of reperfusion and kidney tissues samples were obtained for histopathological investigation in all groups. To date, no more histopathological changes on intestinal I/R injury in rats by UD treatment have been reported. Renal I/R caused severe histopathological injury including tubular damage, atrophy dilatation, loss of brush border and hydropic epithelial cell degenerations, renal corpuscle atrophy, glomerular shrinkage, markedly focal mononuclear cell infiltrations in the kidney. UD treatment significantly attenuated the severity of intestinal I/R injury and significantly lowered tubulointerstitial damage score than the I/R group. The number of PCNA and TUNEL positive cells in the control and UD alone groups was negligible. When kidney sections were PCNA and TUNEL stained, there was a clear increase in the number of positive cells in the I/R group rats in the renal cortical tissues. However, there is a significant reduction in the activity of PCNA and TUNEL in kidney tissue of renal injury induced by renal I/R with UD therapy. Our results suggest that administration of UD attenuates renal I/R injury. These results suggest that UD treatment has a protective effect against renal damage induced by renal I/R. This protective effect is possibly due to its ability to inhibit I/R induced renal damage, apoptosis and cell proliferation.

  17. Prevention of ischemia-reperfusion lung injury during static cold preservation by supplementation of standard preservation solution with HEMO2life® in pig lung transplantation model.

    Glorion, M; Polard, V; Favereau, F; Hauet, T; Zal, F; Fadel, E; Sage, E

    2017-10-25

    We describe the results of adding a new biological agent HEMO 2 life ® to a standard preservation solution for hypothermic static lung preservation aiming to improve early functional parameters after lung transplantation. HEMO 2 life ® is a natural oxygen carrier extracted from Arenicola marina with high oxygen affinity developed as an additive to standard organ preservation solutions. Standard preservation solution (Perfadex ® ) was compared with Perfadex ® associated with HEMO 2 life ® and with sham animals after 24 h of hypothermic preservation followed by lung transplantation. During five hours of lung reperfusion, functional parameters and biomarkers expression in serum and in bronchoalveolar lavage fluid (BALF) were measured. After five hours of reperfusion, HEMO 2 life ® group led to significant improvement in functional parameters: reduction of graft vascular resistance (p preservation improves early graft function after prolonged cold ischemia in lung transplantation.

  18. Neuroprotective effects of the antioxidant action of 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride against ischemic neuronal damage in the brain

    Soo Young Choi

    2013-07-01

    Full Text Available Ischemia is characterized by oxidative stress and changes in theantioxidant defense system. Our recent in vitro study showedthat 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochlorideprotects cortical astrocytes against oxidative stress. In the currentstudy, we examined the effects of 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride on ischemia-induced neuronaldamage in a gerbil ischemia/reperfusion models. Extensive neuronaldeath in the hippocampal CA1 area was observed 4 daysafter ischemia/reperfusion. Intraperitoneal injection of 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride (0.3 mg/kgbody weight significantly prevented neuronal death in the CA1region of the hippocampus in response to transient forebrainischemia. 2-Cyclopropylimino-3-methyl-1,3-thiazoline hydrochlorideadministration reduced ischemia-induced increases inreactive oxygen species levels and malondialdehyde content. Italso attenuated the associated reductions in glutathione level andsuperoxide dismutase, catalase, and glutathione peroxidaseactivities. Taken together, our results suggest that 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride protects againstischemia-induced neuronal damage by reducing oxidative stressthrough its antioxidant actions. [BMB Reports 2013; 46(7:370-375

  19. Suv39h1 Protects from Myocardial Ischemia-Reperfusion Injury in Diabetic Rats

    Bo Yang

    2014-04-01

    Full Text Available Background: Patients with diabetes are at increased risk of ischemic events. Suv39h1 is a histone methyltransferase that catalyzes the methylation of histone 3 lysine 9, which is associated with the suppression of inflammatory genes in diabetes. However, the role of Suv39h1 in myocardial ischemia/reperfusion (I/R injury under diabetic condition has not been evaluated. Methods: To generate diabetic model, male SD rats were fed with 60% fat diet followed by intraperitoneal injection with 40mg/kg streptozotocin. Adenovirus encoding Suv39h1 gene was used for Suv39h1 overexpression. Each rat received injections of adenovirus at five myocardial sites. Three days after gene transfection, each rat was subjected to left main coronary artery occlusion and reperfusion. After 30 min ischemia and reperfusion for 4 h, the rats were euthanized for real-time PCR, Western blot, immunohistochemical staining, and morphometric analysis. Results: Delivery of Ad-Suv39h1 into the hearts of diabetic rats could markedly increase Suv39h1 expression. Up-regulation of Suv39h1 significantly reduced infarct size and tissue damage after I/R injury, which was associated with protection from apoptosis of cardiac myocytes and reduction of inflammatory response. In addition, compared with injury group, Ad-Suv39h1 led to a decreased activity of mitogen-activated protein kinase family and its down-steam transcriptional factor NF-κB. Conclusion: Overexpression of Suv39h1 results in the de-activation of proinflammatory pathways and reduced apoptosis and myocardial injury. Therefore, Suv39h1 might represent a novel therapeutic strategy to reduce I/R injury under diabetic condition.

  20. Melatonin ameliorates myocardial ischemia reperfusion injury through SIRT3-dependent regulation of oxidative stress and apoptosis.

    Zhai, Mengen; Li, Buying; Duan, Weixun; Jing, Lin; Zhang, Bin; Zhang, Meng; Yu, Liming; Liu, Zhenhua; Yu, Bo; Ren, Kai; Gao, Erhe; Yang, Yang; Liang, Hongliang; Jin, Zhenxiao; Yu, Shiqiang

    2017-09-01

    Sirtuins are a family of highly evolutionarily conserved nicotinamide adenine nucleotide-dependent histone deacetylases. Sirtuin-3 (SIRT3) is a member of the sirtuin family that is localized primarily to the mitochondria and protects against oxidative stress-related diseases, including myocardial ischemia/reperfusion (MI/R) injury. Melatonin has a favorable effect in ameliorating MI/R injury. We hypothesized that melatonin protects against MI/R injury by activating the SIRT3 signaling pathway. In this study, mice were pretreated with or without a selective SIRT3 inhibitor and then subjected to MI/R operation. Melatonin was administered intraperitoneally (20 mg/kg) 10 minutes before reperfusion. Melatonin treatment improved postischemic cardiac contractile function, decreased infarct size, diminished lactate dehydrogenase release, reduced the apoptotic index, and ameliorated oxidative damage. Notably, MI/R induced a significant decrease in myocardial SIRT3 expression and activity, whereas the melatonin treatment upregulated SIRT3 expression and activity, and thus decreased the acetylation of superoxide dismutase 2 (SOD2). In addition, melatonin increased Bcl-2 expression and decreased Bax, Caspase-3, and cleaved Caspase-3 levels in response to MI/R. However, the cardioprotective effects of melatonin were largely abolished by the selective SIRT3 inhibitor 3-(1H-1,2,3-triazol-4-yl)pyridine (3-TYP), suggesting that SIRT3 plays an essential role in mediating the cardioprotective effects of melatonin. In vitro studies confirmed that melatonin also protected H9c2 cells against simulated ischemia/reperfusion injury (SIR) by attenuating oxidative stress and apoptosis, while SIRT3-targeted siRNA diminished these effects. Taken together, our results demonstrate for the first time that melatonin treatment ameliorates MI/R injury by reducing oxidative stress and apoptosis via activating the SIRT3 signaling pathway. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons

  1. Role of necroptosis in autophagy signaling during hepatic ischemia and reperfusion

    Hong, Jeong-Min; Kim, Seok-Joo; Lee, Sun-Mee, E-mail: sunmee@skku.edu

    2016-10-01

    Ischemia and reperfusion (I/R) is a complex phenomenon involving massive inflammation and cell death. Necroptosis refers to a newly described cell death as “programmed necrosis” that is controlled by receptor-interacting protein kinase (RIP) 1 and RIP3, which is involved in the pathogenesis of several inflammatory diseases. Autophagy is an essential cytoprotective system that is rapidly activated in response to various stimuli and involves crosstalk between different modes of cell death and inflammation. In this study, we investigated pattern changes in necroptosis and its role in autophagy signaling during hepatic I/R. Male C57BL/6 mice were subjected to 60 min of ischemia followed by 3 h reperfusion. Necrostatin-1 (Nec-1, a necroptosis inhibitor; 1.65 mg/kg) was administered intraperitoneally 5 min before reperfusion. Hepatic I/R significantly increased the level of RIP3, phosphorylated RIP1 and RIP3 protein expression, and RIP1/RIP3 necrosome formation, which were attenuated by Nec-1. I/R also significantly increased serum levels of alanine aminotransferase, tumor necrosis factor-α, and interleukin-6, which were attenuated by Nec-1. Meanwhile, hepatic I/R activated autophagy and mitophagy, as evidenced by increased LC3-II, PINK1, and Parkin, and decreased sequestosome 1/p62 protein expression. Nec-1 attenuated these changes and attenuated the increased levels of autophagy-related protein (ATG) 3, ATG7, Rab7, and cathepsin B protein expression during hepatic I/R. Moreover, hepatic I/R activated the extracellular signal-regulated kinase (ERK) pathway, and Nec-1 attenuated this increase. Taken together, our findings suggest that necroptosis contributes to hepatic damage during I/R, which induces autophagy via ERK activation. - Highlights: • Hepatic I/R induces RIP1/RIP3-dependent necroptosis. • Necroptosis contributes to hepatic I/R injury. • Necroptosis activates autophagic flux via ERK activation during hepatic I/R.

  2. Oxygen toxicity

    C. A. van der Westhuizen

    1990-07-01

    Full Text Available Oxygen has been discovered about 200 years ago. Since then the vital physiological involvement of oxygen in various biologi­cal processes, mainly energy production, has been established. However, in the body molecular oxygen can be converted to toxic oxygen metabolites such as superoxide anion, hydrogen peroxide, the hydroxyl radical and singlet oxygen. These toxic metabolites are produced mainly in the mitochondria, plasma membranes and endoplasmic reticulum.

  3. Antioxidative protection of dietary bilberry, chokeberry and Lactobacillus plantarum HEAL19 in mice subjected to intestinal oxidative stress by ischemia-reperfusion

    Ahrné Siv

    2011-01-01

    Full Text Available Abstract Background Ischemia-reperfusion (I/R in the intestines is an inflammatory condition which activates leukocytes and reactive oxygen species (ROS and leads to lipid peroxidation and DNA damage. Bilberry and chokeberry fruits are rich sources of polyphenols which may act as antioxidants and prevent lipid peroxidation. Lactic acid bacteria (LAB may improve microbial status in the intestines and increase the metabolic activity towards polyphenolic degradation. The aim of the study was to clarify antioxidative effects of bilberry and chokeberry fruits alone and with addition of a LAB-strain, Lactobacillus plantarum HEAL19, in an I/R-model in mice. Methods Male BALB/cJ mice were fed the experimental diets for 10 days. Diets consisted of standard chow supplemented with either bilberry (Vaccinium myrtillus or chokeberry (Aronia × prunifolia powder alone or in combination with the LAB-strain Lactobacillus plantarum HEAL19. I/R-injury was induced by holding superior mesenteric artery clamped for 30 minutes followed by reperfusion for 240 minutes. Thereafter, colonic and caecal tissues and contents were collected. Malondialdehyde (MDA was used as indicator of lipid peroxidation and was measured by a calorimetric assay, lactobacilli were cultured on Rogosa agar plates and Enterobacteriaceae on VRBG agar plates, anthocyanins and phenolic acids were analysed by HPLC-DAD-ESI-MSn. Results MDA was significantly decreased in the colon of groups fed bilberry alone (p = 0.030 and in combination with L. plantarum HEAL19 (p = 0.021 compared to the IR-control but not in chokeberry-fed groups. Supplementation with bilberry or chokeberry alone reduced the total number of lactobacilli on the mucosa. Higher concentrations of anthocyanins were found in the colon than in the caecum content of mice. A more varied composition of different anthocyanins was also observed in the colon content compared to the caecum of bilberry-fed mice. Phenolic acids formed by

  4. PET imaging of cerebral perfusion and oxygen consumption in acute ischemic stroke: Relation to outcome

    Marchal, G.; Serrati, C.; Rioux, P.; Petit-Taboue, M.C.; Viader, F.; Sayette, V. de la; Doze, F. le; Lonchon, P; Derlon, J.M.; Orgogozo, J.M.; Baron, J.C.

    1993-01-01

    The authors used positron emission tomography (PET) to assess the relation between combined imaging of cerebral blood flow and oxygen consumption 5-18 h after first middle cerebral artery (MCA) stroke and neurological outcome at 2 months. All 18 patients could be classified into three visually defined PET patterns of perfusion and oxygen consumption changes. Pattern 1 suggested extensive irreversible damage and was consistently associated with poor outcome. Pattern 2 suggested continuing ischemia and was associated with variable outcome. Pattern 3 with hyperperfusion and little or no metabolic alteration, was associated with excellent recovery, which suggests that early reperfusion is beneficial. This relation between PET and outcome was highly significant. The results suggest that within 5-18 h of stroke onset, PET is a good predictor of outcome in patterns 1 and 3, for which therapy seems limited. The absence of predictive value for pattern 2 suggests that it is due to a reversible ischemic state that is possibly amenable to therapy. These findings may have important implications for acute MCA stroke management and for patients' selection for therapeutic trials

  5. Effects of Laser Printer-Emitted Engineered Nanoparticles on Cytotoxicity, Chemokine Expression, Reactive Oxygen Species, DNA Methylation, and DNA Damage: A Comprehensive in Vitro Analysis in Human Small Airway Epithelial Cells, Macrophages, and Lymphoblasts.

    Pirela, Sandra V; Miousse, Isabelle R; Lu, Xiaoyan; Castranova, Vincent; Thomas, Treye; Qian, Yong; Bello, Dhimiter; Kobzik, Lester; Koturbash, Igor; Demokritou, Philip

    2016-02-01

    Engineered nanomaterials (ENMs) incorporated into toner formulations of printing equipment become airborne during consumer use. Although information on the complex physicochemical and toxicological properties of both toner powders and printer-emitted particles (PEPs) continues to grow, most toxicological studies have not used the actual PEPs but rather have primarily used raw toner powders, which are not representative of current exposures experienced at the consumer level during printing. We assessed the biological responses of a panel of human cell lines to PEPs. Three physiologically relevant cell lines--small airway epithelial cells (SAECs), macrophages (THP-1 cells), and lymphoblasts (TK6 cells)--were exposed to PEPs at a wide range of doses (0.5-100 μg/mL) corresponding to human inhalation exposure durations at the consumer level of 8 hr or more. Following treatment, toxicological parameters reflecting distinct mechanisms were evaluated. PEPs caused significant membrane integrity damage, an increase in reactive oxygen species (ROS) production, and an increase in pro-inflammatory cytokine release in different cell lines at doses equivalent to exposure durations from 7.8 to 1,500 hr. Furthermore, there were differences in methylation patterns that, although not statistically significant, demonstrate the potential effects of PEPs on the overall epigenome following exposure. The in vitro findings obtained in this study suggest that laser printer-emitted engineered nanoparticles may be deleterious to lung cells and provide preliminary evidence of epigenetic modifications that might translate to pulmonary disorders.

  6. Protective Effect of SGK1 in Rat Hippocampal Neurons Subjected to Ischemia Reperfusion

    Wei Zhang

    2014-07-01

    Full Text Available Background/Aims: To investigate the protective effect of SGK1 (serum- and glucocorticoid-inducible protein kinase 1 in rat hippocampal neurons in vitro and in vivo following ischemia reperfusion (I/R. Methods: Isolated rat hippocampal neurons were subjected to 2 h of oxygen and glucose deprivation (OGD then returned to normoxic conditions for 10, 30 or 60 min. Cell apoptosis and protein expression of SGK1 were analyzed. To examine SGK1 function, we overexpressed SGK1 in rat hippocampal neurons. Finally we examined the involvement of PI3K/Akt/GSK3β signaling by treating the cells (untransfected or transfected with expression vector encoding SGK1 with the PI3K inhibitor LY294002. Findings were confirmed in vivo in a rat model of middle cerebral artery occlusion. Results: I/R caused a time-dependent increase in apoptosis, both in vitro and in vivo. SGK1 protein levels decreased significantly under the same conditions. Overexpression of SGK1 reduced apoptosis following OGD or I/R compared to cells transfected with empty vector and subjected to the same treatment, or sham-operated animals. Addition of LY294002 revealed that the action of SGK1 in suppressing apoptosis was mediated by the PI3K/Akt/GSK3β pathway. Conclusion: SGK1 plays a protective role in ischemia reperfusion in rat hippocampal neurons, exerting its effects via the PI3K/Akt/GSK3β pathway.

  7. Cardioprotective Effects of Quercetin in Cardiomyocyte under Ischemia/Reperfusion Injury

    Yi-Wen Chen

    2013-01-01

    Full Text Available Quercetin, a polyphenolic compound existing in many vegetables, fruits, has antiinflammatory, antiproliferation, and antioxidant effect on mammalian cells. Quercetin was evaluated for protecting cardiomyocytes from ischemia/reperfusion injury, but its protective mechanism remains unclear in the current study. The cardioprotective effects of quercetin are achieved by reducing the activity of Src kinase, signal transducer and activator of transcription 3 (STAT3, caspase 9, Bax, intracellular reactive oxygen species production, and inflammatory factor and inducible MnSOD expression. Fluorescence two-dimensional differential gel electrophoresis (2D-DIGE and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS can reveal the differentially expressed proteins of H9C2 cells treated with H2O2 or quercetin. Although 17 identified proteins were altered in H2O2-induced cells, these proteins such as alpha-soluble NSF attachment protein (α-SNAP, Ena/VASP-like protein (Evl, and isopentenyl-diphosphate delta-isomerase 1 (Idi-1 were reverted by pretreatment with quercetin, which correlates with kinase activation, DNA repair, lipid, and protein metabolism. Quercetin dephosphorylates Src kinase in H2O2-induced H9C2 cells and likely blocks the H2O2-induced inflammatory response through STAT3 kinase modulation. This probably contributes to prevent ischemia/reperfusion injury in cardiomyocytes.

  8. Hyperglycemia Aggravates Hepatic Ischemia Reperfusion Injury by Inducing Chronic Oxidative Stress and Inflammation

    Yihan Zhang

    2016-01-01

    Full Text Available Aim. To investigate whether hyperglycemia will aggravate hepatic ischemia reperfusion injury (HIRI and the underlying mechanisms. Methods. Control and streptozotocin-induced diabetic Sprague-Dawley rats were subjected to partial hepatic ischemia reperfusion. Liver histology, transferase, inflammatory cytokines, and oxidative stress were assessed accordingly. Similarly, BRL-3A hepatocytes were subjected to hypoxia/reoxygenation (H/R after high (25 mM or low (5.5 mM glucose culture. Cell viability, reactive oxygen species (ROS, and activation of nuclear factor-erythroid 2-related factor 2 (Nrf2 and nuclear factor of kappa light polypeptide gene enhancer in B-cells (NF-κB were determined. Results. Compared with control, diabetic rats presented more severe hepatic injury and increased hepatic inflammatory cytokines and oxidative stress. HIRI in diabetic rats could be ameliorated by pretreatment of N-acetyl-L-cysteine (NAC or apocynin. Excessive ROS generation and consequent Nrf2 and NF-κB translocation were determined after high glucose exposure. NF-κB translocation and its downstream cytokines were further increased in high glucose cultured group after H/R. While proper regulation of Nrf2 to its downstream antioxidases was observed in low glucose cultured group, no further induction of Nrf2 pathway by H/R after high glucose culture was identified. Conclusion. Hyperglycemia aggravates HIRI, which might be attributed to chronic oxidative stress and inflammation and potential malfunction of antioxidative system.

  9. Pharmacological prevention of reperfusion injury in acute myocardial infarction. A potential role for adenosine as a therapeutic agent.

    Quintana, Miguel; Kahan, Thomas; Hjemdahl, Paul

    2004-01-01

    The concept of reperfusion injury, although first recognized from animal studies, is now recognized as a clinical phenomenon that may result in microvascular damage, no-reflow phenomenon, myocardial stunning, myocardial hibernation and ischemic preconditioning. The final consequence of this event is left ventricular (LV) systolic dysfunction leading to increased morbidity and mortality. The typical clinical case of reperfusion injury occurs in acute myocardial infarction (MI) with ST segment elevation in which an occlusion of a major epicardial coronary artery is followed by recanalization of the artery. This may occur either spontaneously or by means of thrombolysis and/or by primary percutaneous coronary intervention (PCI) with efficient platelet inhibition by aspirin (acetylsalicylic acid), clopidogrel and glycoprotein IIb/IIIa inhibitors. Although the pathophysiology of reperfusion injury is complex, the major role that neutrophils play in this process is well known. Neutrophils generate free radicals, degranulation products, arachidonic acid metabolites and platelet-activating factors that interact with endothelial cells, inducing endothelial injury and neutralization of nitrous oxide vasodilator capacity. Adenosine, through its multi-targeted pharmacological actions, is able to inhibit some of the above-mentioned detrimental effects. The net protective of adenosine in in vivo models of reperfusion injury is the reduction of the infarct size, the improvement of the regional myocardial blood flow and of the regional function of the ischemic area. Additionally, adenosine preserves the post-ischemic coronary flow reserve, coronary blood flow and the post-ischemic regional contractility. In small-scale studies in patients with acute MI, treatment with adenosine has been associated with smaller infarcts, less no-reflow phenomenon and improved LV function. During elective PCI adenosine reduced ST segment shifts, lactate production and ischemic symptoms. During the

  10. Sevoflurane mitigates shedding of hyaluronan from the coronary endothelium, also during ischemia/reperfusion: an ex vivo animal study

    Chen C

    2016-04-01

    colloid hydroxyethyl starch was significantly decreased by sevoflurane vs the control. We conclude that application of sevoflurane preserves the coronary endothelial glycocalyx, especially HA, sustaining the vascular barrier against ischemic damage. This may explain beneficial effects associated with clinical use of volatile anesthetics against ischemia/reperfusion injury. Keywords: endothelial glycocalyx, hyaluronan, ischemia-reperfusion injury, volatile anesthetics, preconditioning

  11. Growth Arrest-Specific Protein 6 is Hepatoprotective Against Ischemia/Reperfusion Injury

    Llacuna, Laura; Bárcena, Cristina; Bellido-Martín, Lola; Fernández, Laura; Stefanovic, Milica; Marí, Montserrat; García-Ruiz, Carmen; Fernández-Checa, José C.; de Frutos, Pablo García; Morales, Albert

    2010-01-01

    Growth arrest-specific gene 6 (GAS6) promotes growth and cell survival during tissue repair and development in different organs, including the liver. However, the specific role of GAS6 in liver ischemia/reperfusion (I/R) injury has not been previously addressed. Here, we report an early increase in serum GAS6 levels following I/R exposure. Moreover, unlike wild type mice, Gas6-/- mice were highly sensitive to partial hepatic I/R, with 90% of mice dying within 12 hours of reperfusion due to massive hepatocellular injury. I/R induced early hepatic AKT phosphorylation in wild type but not in Gas6-/- mice, without significant changes in JNK phosphorylation or nuclear NF-κB translocation, whereas hepatic IL-1β and TNF mRNA levels were higher in Gas6-/- mice compared to wild type mice. In line with the in vivo data, in vitro studies indicated that GAS6 induced AKT phosphorylation in primary mouse hepatocytes protecting them from hypoxia-induced cell death, while GAS6 diminished lipopolysaccharide (LPS)-induced cytokine expression (IL-1β and TNF) in murine macrophages. Finally, in vivo recombinant GAS6 treatment not only rescued GAS6 knockout mice from I/R-induced severe liver damage, but also attenuated hepatic damage in wild type mice following I/R. In conclusion, our data uncover GAS6 as a new player in liver I/R injury, emerging as a potential therapeutic target to reduce post-ischemic hepatic damage. PMID:20730776

  12. Growth arrest-specific protein 6 is hepatoprotective against murine ischemia/reperfusion injury.

    Llacuna, Laura; Bárcena, Cristina; Bellido-Martín, Lola; Fernández, Laura; Stefanovic, Milica; Marí, Montserrat; García-Ruiz, Carmen; Fernández-Checa, José C; García de Frutos, Pablo; Morales, Albert

    2010-10-01

    Growth arrest-specific gene 6 (GAS6) promotes growth and cell survival during tissue repair and development in different organs, including the liver. However, the specific role of GAS6 in liver ischemia/reperfusion (I/R) injury has not been previously addressed. Here we report an early increase in serum GAS6 levels after I/R exposure. Moreover, unlike wild-type (WT) mice, Gas6(-/-) mice were highly sensitive to partial hepatic I/R, with 90% of the mice dying within 12 hours of reperfusion because of massive hepatocellular injury. I/R induced early hepatic protein kinase B (AKT) phosphorylation in WT mice but not in Gas6(-/-) mice without significant changes in c-Jun N-terminal kinase phosphorylation or nuclear factor kappa B translocation, whereas hepatic interleukin-1β (IL-1β) and tumor necrosis factor (TNF) messenger RNA levels were higher in Gas6(-/-) mice versus WT mice. In line with the in vivo data, in vitro studies indicated that GAS6 induced AKT phosphorylation in primary mouse hepatocytes and thus protected them from hypoxia-induced cell death, whereas GAS6 diminished lipopolysaccharide-induced cytokine expression (IL-1β and TNF) in murine macrophages. Finally, recombinant GAS6 treatment in vivo not only rescued GAS6 knockout mice from severe I/R-induced liver damage but also attenuated hepatic damage in WT mice after I/R. Our data have revealed GAS6 to be a new player in liver I/R injury that is emerging as a potential therapeutic target for reducing postischemic hepatic damage.

  13. Metallothionein-II Inhibits Lipid Peroxidation and Improves Functional Recovery after Transient Brain Ischemia and Reperfusion in Rats

    Araceli Diaz-Ruiz

    2014-01-01

    Full Text Available After transient cerebral ischemia and reperfusion (I/R, damaging mechanisms, such as excitotoxicity and oxidative stress, lead to irreversible neurological deficits. The induction of metallothionein-II (MT-II protein is an endogenous mechanism after I/R. Our aim was to evaluate the neuroprotective effect of MT-II after I/R in rats. Male Wistar rats were transiently occluded at the middle cerebral artery for 2 h, followed by reperfusion. Rats received either MT (10 μg per rat i.p. or vehicle after ischemia. Lipid peroxidation (LP was measured 22 h after reperfusion in frontal cortex and hippocampus; also, neurological deficit was evaluated after ischemia, using the Longa scoring scale. Infarction area was analyzed 72 hours after ischemia. Results showed increased LP in frontal cortex (30.7% and hippocampus (26.4%, as compared to control group; this effect was fully reversed by MT treatment. Likewise, we also observed a diminished neurological deficit assessed by the Longa scale in those animals treated with MT compared to control group values. The MT-treated group showed a significant (P<0.05 reduction of 39.9% in the infarction area, only at the level of hippocampus, as compared to control group. Results suggest that MT-II may be a novel neuroprotective treatment to prevent ischemia injury.

  14. The role of curcumin on intestinal oxidative stress, cell proliferation and apoptosis after ischemia/reperfusion injury in rats.

    Yucel, Ahmet Fikret; Kanter, Mehmet; Pergel, Ahmet; Erboga, Mustafa; Guzel, Ahmet

    2011-12-01

    The aim of this study was to demonstrate the role of curcumin on oxidative stress, cell proliferation and apoptosis in the rat intestinal mucosa after ischemia/reperfusion (I/R). A total of 30 male Wistar albino rats were divided into three groups: sham, I/R and I/R+ curcumin; each group contain 10 animals. Sham group animals underwent laparotomy without I/R injury. After I/R groups animals underwent laparotomy, 1 h of superior mesenteric artery ligation were followed by 1 h of reperfusion. In the curcumin group, 3 days before I/R, curcumin (100 mg/kg) was administered by gastric gavage. All animals were sacrificed at the end of reperfusion and intestinal tissues samples were obtained for biochemical and histopathological investigation in all groups. Curcumin treatment significantly decreased the elevated tissue malondialdehyde levels and increased of reduced superoxide dismutase, and glutathione peroxidase enzyme activities in intestinal tissues samples. I/R caused severe histopathological injury including mucosal erosions and villous congestion and hemorrhage. Curcumin treatment significantly attenuated the severity of intestinal I/R injury, with inhibiting of I/R-induced apoptosis and cell proliferation. These results suggest that curcumin treatment has a protective effect against intestinal damage induced by intestinal I/R. This protective effect is possibly due to its ability to inhibit I/R-induced oxidative stress, apoptosis and cell proliferation.

  15. Regional blood flow distribution and oxygen metabolism during mesenteric ischemia and congestion.

    Cruz, Ruy J; Garrido, Alejandra G; Ribeiro, Cristiane M F; Harada, Tomoyuki; Rocha-e-Silva, Mauricio

    2010-06-01

    Acute mesenteric ischemia is a potentially fatal vascular emergency with mortality rates ranging between 60% and 80%. Several studies have extensively examined the hemodynamic and metabolic effects of superior mesenteric artery occlusion. On the other hand, the cardiocirculatory derangement and the tissue damage induced by intestinal outflow obstruction have not been investigated systematically. For these reasons we decided to assess the initial impact of venous mesenteric occlusion on intestinal blood flow distribution, and correlate these findings with other systemic and regional perfusion markers. Fourteen mongrel dogs were subjected to 45 min of superior mesenteric artery (SMAO) or vein occlusion (SMVO), and observed for 120 min after reperfusion. Systemic hemodynamics were evaluated using Swan-Ganz and arterial catheters. Regional blood flow (ultrasonic flow probes), intestinal O(2)-derived variables, and mesenteric-arterial and tonometric-arterial pCO(2) gradients (D(mv-a)pCO(2) and D(t-a)pCO(2)) were also calculated. SMVO was associated with hypotension and low cardiac output. A significant increase in the regional pCO(2) gradients was also observed in both groups during the ischemic period. After reperfusion, a progressive reduction in D(mv-a)pCO(2) occurred in the SMVO group; however, no improvement in D(t-a)pCO(2) was observed. The histopathologic injury scores were 2.7 +/- 0.5 and 4.8 +/- 0.2 for SMAO and SMVO, respectively. SMV occlusion promoted early and significant hemodynamic and metabolic derangement at systemic and regional levels. Additionally, systemic pCO(2) gradient is not a reliable parameter to evaluate the local intestinal oxygenation. Finally, the D(t-a)pCO(2) correlates with histologic changes during intestinal congestion or ischemia. However, minor histologic changes cannot be detected using this methodology. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  16. Protective Effect of N-Acetylcystein and Resveratrol on Ischemia-Reperfusion Injury in Rat Ovary

    Avni Kılıç

    2016-06-01

    Full Text Available Objective: The aim of this study is evaluating the protective activity of N-acetyl cysteine and resveratrol treatment against ischemia - reperfusion damage created experimentally in rat ovaries. Methods: 42 female Wistar rats were used in our study. Rats were separated randomly into six groups consisting of seven rats as sham, torsion, torsion- detorsion, torsion-detorsion+saline, torsion-detorsion+resveretrol (20 mg/kg and torsion- detorsion+N-acetyl cysteine (150 mg/kg. Except Sham, ovarian torsion procedure was implemented to all other groups for 2 hours. Detorsion procedure was implemented to other groups for 2 hours, except the torsion group. Medications were given through intraperitoneal way half an hour before the detorsion procedure in saline (two milliliter, resveratrol (20 mg/kg and N-acetyl cysteine (150 mg/kg groups. Then, 2 ml of blood samples were drawn for markers of oxidative stress and tumour necrosis factor-alpha (TNF-α work and the ovaries, which were torsioned for the histologic examination, were ex­tracted from all rats. Edema, congestion, hemorrhage, leuko­cyte infiltration and degeneration of follicles were evaluated by histopathological examination. Results: According to histopathologic damage scores, the least damage was seen in sham group and the most damage was seen T-DT group (1.00±0.81 vs. 11.00±1.15, respectively; p<0.001. It was seen that resveratrol and N-acetyl cysteine treatments were effective in decreasing tissue damage (total damage score average 83.85±0.89 vs. 3.85±0.89, respec­tively; p<0.001, and on the other hand there was not any dif­ference between resveratrol and N-acetyl cysteine treatments (p=0.966. Besides, it was determined that oxidative stress levels were higher in torsion - detorsion group and the resve­ratrol and N-acetyl cysteine treatment caused a significant de­crease in oxidative stress levels. In additionally, the reductions of TNF-α levels were found to be equally effective in

  17. Curcumin inhibits endoplasmic reticulum stress induced by cerebral ischemia-reperfusion injury in rats

    Zhu, Haiying; Fan, Yanxia; Sun, Hongyu; Chen, Liyan; Man, Xiao

    2017-01-01

    The aim of the present study was to observe the dynamic changes of the growth arrest and DNA damage-inducible 153 (GADD153) gene and caspase-12 in the brain tissue of rats with cerebral ischemia-reperfusion injury (CIRI) and the impact of curcumin pretreatment. A total of 60 rats were randomly divided into the normal group (N), the sham operation group (S), the dimethyl sulfoxide control group (D) and the curcumin treatment group (C). For group D and C, 12 (T1), 24 (T2) and 72 h (T3) of reperfusion were performed after 2 h ischemia. The expression levels of GADD153 and caspase-12 in the brain tissue were detected and compared among the groups by immunohistochemistry, immunofluorescence double staining and western blotting. The expression levels of GADD153 and caspase-12 were increased at T1compared with groups N and S, and the expression of caspase-12 peaked at T2 in group D, while GADD153 was increased until T3 in group D. Compared with group D, the expression levels of GADD153 and caspase-12 in group C at T2 and T3 were significantly decreased (P<0.05). Endoplasmic reticulum stress is involved in the pathological process of CIRI. Curcumin may decrease the expression levels of the above two factors, thus exhibiting protective effects against CIRI in rats. PMID:29067098

  18. Pretreatment with soluble ST2 reduces warm hepatic ischemia/reperfusion injury

    Yin Hui; Huang Baojun; Yang Heng; Huang Yafei; Xiong Ping; Zheng Fang; Chen Xiaoping; Chen Yifa; Gong Feili

    2006-01-01

    The interleukin-1 receptor-like protein ST2 exists in both membrane-bound (ST2L) and soluble form (sST2). ST2L has been found to play an important regulatory role in Th2-type immune response, but the function of soluble form of ST2 remains to be elucidated. In this study, we report the protective effect of soluble ST2 on warm hepatic ischemia/reperfusion injury. We constructed a eukaryotic expression plasmid, psST2-Fc, which expresses functional murine soluble ST2-human IgG1 Fc (sST2-Fc) fusion protein. The liver damage after ischemia/reperfusion was significantly attenuated by the expression of this plasmid in vivo. sST2-Fc remarkably inhibited the activation of Kupffer cells and the production of proinflammatory mediators TNF-α and IL-6. Furthermore, the levels of TLR4 mRNA and the nuclear translocation of NF-κB were also suppressed by pretreatment with sST2-Fc. These results thus identified soluble ST2 as a negative regulator in hepatic I/R injury, possibly via ST2-TLR4 pathway

  19. Effects of Urtica dioica on hepatic ischemia‐reperfusion injury in rats

    Kandis, Hayati; Karapolat, Sami; Yildirim, Umran; Saritas, Ayhan; Gezer, Suat; Memisogullari, Ramazan

    2010-01-01

    OBJECTIVES: To evaluate the effects of Urtica dioica on hepatic ischemia‐reperfusion injury. METHODS: Thirty adult male Wistar albino rats were divided into three groups: sham group (group 1), control group (group 2), and Urtica dioica group (group 3). All the rats were exposed to hepatic ischemia for 60 min, followed by 60 min of reperfusion. In group 2, a total of 2 ml/kg 0.9% saline solution was given intraperitoneally. In group 3, a total of 2 ml/kg Urtica dioica was given intraperitoneally. At the end of the procedure, liver tissue and blood samples were taken from all rats. Serum aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, ceruloplasmin, catalase, paraoxonase, arylesterase, and lipid hydroperoxide levels were measured. Liver tissue histopathologies were also evaluated by light microscopy. RESULTS: Serum aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase levels were significantly higher in group 2 than in group 1, and significantly lower in group 3 than in group 2. Also, group 2 had higher serum lipid hydroperoxides and ceruloplasmin levels but lower catalase, paraoxonase, and arylesterase levels than group 1. In group 3, serum lipid hydroperoxides and ceruloplasmin levels were significantly lower, and catalase, paraoxonase, and arylesterase levels were higher than those in group 2. Histopathological examination showed that liver tissue damage was significantly decreased in group 3 compared with group 2. CONCLUSIONS: Urtica dioica has a protective effect on the liver in hepatic ischemia‐reperfusion‐injured rats. PMID:21340227

  20. Neuroprotective effect of curcumin on spinal cord in rabbit model with ischemia/reperfusion.

    Liu, Zhi-Qiang; Xing, Shan-Shan; Zhang, Wei

    2013-03-01

    Ischemic/reperfusion (I/R) injury of the spinal cord is a serious complication that can result from thoracoabdominal aortic surgery. To investigate the neuroprotective effect of curcumin against I/R injury in a rabbit model. A total of 36 rabbits were randomly divided into three groups: sham, I/R, and curcumin-treated group. Rabbits were subject to 30-min aortic occlusion to induce transient spinal cord ischemia. Neurological function was observed after reperfusion and spinal cord segment (L3-L5) was collected for histopathological evaluation. Malondialdehyde (MDA) and total superoxide dismutase (SOD) activity were also assayed. Rabbits in I/R group were induced to paraplegia. While after 48-hour treatment, compared with I/R group, curcumin significantly improved neurological function, reduced cell apoptosis and MDA levels as well as increased SOD activity (P curcumin, at least in an animal model, can attenuate transient spinal cord ischemic injury potentially via reducing oxidative damage, which may provide a novel approach in the treatment of spinal cord ischemic injury.

  1. Comparative Effects of Triflusal, S-Adenosylmethionine, and Dextromethorphan over Intestinal Ischemia/Reperfusion Injury

    Carlos R. Cámara-Lemarroy

    2011-01-01

    Full Text Available Ischemia/reperfusion (I/R is a condition that stimulates an intense inflammatory response. No ideal treatment exists. Triflusal is an antiplatelet salicylate derivative with anti-inflammatory effects. S-adenosylmethionine is a metabolic precursor for glutathione, an endogenous antioxidant. Dextromethorphan is a low-affinity N-methyl-D-aspartate receptor inhibitor. There is evidence that these agents modulate some of the pathways involved in I/R physiopathology. Intestinal I/R was induced in rats by clamping the superior mesenteric artery for 60 minutes, followed by 60 minutes of reperfusion. Rats either received saline or the drugs studied. At the end of the procedure, serum concentrations of tumor necrosis factor-alpha (TNF-alpha, malonaldehyde (MDA, and total antioxidant capacity (TAC were determined and intestinal morphology analyzed. I/R resulted in tissue damage, serum TNF-alpha and MDA elevations, and depletion of TAC. All drugs showed tissue protection. Only triflusal reduced TNF-alpha levels. All drugs lowered MDA levels, but only triflusal and S-adenosylmethionine maintained the serum TAC.

  2. Failure of antiarrhythmic drugs to prevent experimental reperfusion ventricular fibrillation.

    Naito, M; Michelson, E L; Kmetzo, J J; Kaplinsky, E; Dreifus, L S

    1981-01-01

    Ninety-nine adult mongrel dogs underwent acute ligation of the proximal left anterior descending coronary artery. Thirty minutes later, the occlusion was released to evaluate the effectiveness of five antiarrhythmic protocols in eliminating reperfusion ventricular fibrillation. The five protocols included: protocol 1 --i.v. lidocaine, preligation and prerelease (n = 19); protocol 2 -- i.v. lidocaine, prereperfusion only (n = 22); protocol 3 -- chronic, oral, daily amiodarone for 2 weeks preligation (n = 19); protocol 4 -- i.v. procainamide, preligation and prereperfusion (n = 21); and protocol 5 -- i.v. verapamil, prereperfusion (n = 18). Each regimen was evaluated with respect to the incidence of reperfusion ventricular fibrillation in dogs that survived to reperfusion, and the results were compared to 77 control dogs that underwent identical coronary artery occlusion and release procedures without drug therapy. The incidence of reperfusion ventricular fibrillation was as follows: protocol 1 -- seven of 15 dogs (47%); protocol 2 -- six of 18 (33%); protocol 3 -- 11 of 16 dogs (69%); protocol 4 -- eight of 17 dogs (47%); and protocol 5 -- 10 of 17 dogs (59%), compared with 36 of 60 (60%) in control dogs. Using chi-square analysis, protocol 2 was beneficial (p antecedent coronary artery ligation periods, and predictive risk indexes for the occurrence of reperfusion ventricular fibrillation were developed. the Mantel-Haenszel method of statistical analysis revealed that none of these protocols resulted in a statistically significant reduction in the incidence of reperfusion ventricular fibrillation. Thus, use of these predictive indexes plus appropriate statistical methods has revealed, unexpectedly, limitations in the efficacy of a spectrum of antiarrhythmic agents in preventing reperfusion ventricular fibrillation.

  3. Mild episodes of tourniquet-induced forearm ischaemia-reperfusion injury results in leukocyte activation and changes in inflammatory and coagulation markers

    Bastawrous Salah S

    2007-05-01

    significance (p = 0.014, although similar trends were observed with neutrophils these did not reach statistical significance. CRP was measured to assess the inflammatory response following mild episodes of ischaemia-reperfusion injury and resulted in a significant increase in the CRP concentration (p = Conclusion Tourniquet induced forearm ischaemia-reperfusion injury results in increased adhesiveness, trapping and activation of leukocytes. We report that, even following a mild ischaemic insult, this leukocyte response is immediately followed by evidence of increased inflammatory response, coagulation activity and endothelial damage. These results may have important implications and this pilot study may lead to a series of trials that shed light on the mechanisms of ischaemia-reperfusion injury, including potential points of therapeutic intervention for pathophysiological conditions.

  4. Surfactant treatment before reperfusion improves the immediate function of lung transplants in rats

    Erasmus, ME; Petersen, AH; Hofstede, G; Haagsman, HP; Oetomo, SB; Prop, J

    An impaired function of alveolar surfactant can cause lung transplant dysfunction early after reperfusion. In this study it was investigated whether treatment with surfactant before reperfusion improves the immediate function of lung transplants and whether an improved transplant function was

  5. DNA damage and autophagy

    Rodriguez-Rocha, Humberto; Garcia-Garcia, Aracely; Panayiotidis, Mihalis I.; Franco, Rodrigo

    2011-01-01

    Both exogenous and endogenous agents are a threat to DNA integrity. Exogenous environmental agents such as ultraviolet (UV) and ionizing radiation, genotoxic chemicals and endogenous byproducts of metabolism including reactive oxygen species can cause alterations in DNA structure (DNA damage). Unrepaired DNA damage has been linked to a variety of human disorders including cancer and neurodegenerative disease. Thus, efficient mechanisms to detect DNA lesions, signal their presence and promote their repair have been evolved in cells. If DNA is effectively repaired, DNA damage response is inactivated and normal cell functioning resumes. In contrast, when DNA lesions cannot be removed, chronic DNA damage triggers specific cell responses such as cell death and senescence. Recently, DNA damage has been shown to induce autophagy, a cellular catabolic process that maintains a balance between synthesis, degradation, and recycling of cellular components. But the exact mechanisms by which DNA damage triggers autophagy are unclear. More importantly, the role of autophagy in the DNA damage response and cellular fate is unknown. In this review we analyze evidence that supports a role for autophagy as an integral part of the DNA damage response.

  6. Effect of short-term ornithine alpha-ketoglutarate pretreatment on intestinal ischemia-reperfusion in rats.

    Gonçalves, Eduardo Silvio Gouveia; Rabelo, Camila Menezes; Prado Neto, Alberico Ximenes do; Garcia, José Huygens Parente; Guimarães, Sérgio Botelho; Vasconcelos, Paulo Roberto Leitão de

    2011-01-01

    To investigate the effects of preventive enteral administration of ornithine alpha-ketoglutarate (OKG) in an ischemia-reperfusion rat model. Sixty rats were randomized into five groups (G1-G5, n = 12). Each group was divided into two subgroups (n = 6) and treated with calcium carbonate (CaCa) or OKG by gavage. Thirty minutes later, the animals were anesthetized with xylazine 15mg + ketamine 1mg ip and subjected to laparotomy. G1-G3 rats served as controls. Rats in groups G4 and G5 were subjected to ischemia for 30 minutes. Ischemia was achieved by clamping the small intestine and its mesentery, delimiting a segment of bowel 5 cm long and 5 cm apart from the ileocecal valve. In addition, G5 rats underwent reperfusion for 30 minutes. Blood samples were collected at the end of the laparotomy (G1), after 30 minutes (G2, G4) and 60 minutes (G3, G5) to determine concentrations of metabolites (pyruvate, lactate), creatine phosphokinase (CPK), thiobarbituric acid reactive substances (TBARS) and glutathione (GSH). There was a significant decrease in tissue pyruvate and lactate and plasma CPK levels in OKG-treated rats at the end of reperfusion period. GSH levels did not change significantly in ischemia and reperfusion groups. However, TBARS levels increased significantly (p<0.05) in tissue samples in OKG-treated rats subjected to ischemia for 30 minutes. Short-term pretreatment with OKG before induction of I/R decreases tissue damage, increases pyruvate utilization for energy production in the Krebs cycle and does not attenuate the oxidative stress in this animal model.

  7. ROS-mediated PARP activity undermines mitochondrial function after permeability transition pore opening during myocardial ischemia-reperfusion.

    Schriewer, Jacqueline M; Peek, Clara Bien; Bass, Joseph; Schumacker, Paul T

    2013-04-18

    Ischemia-reperfusion (I/R) studies have implicated oxidant stress, the mitochondrial permeability transition pore (mPTP), and poly(ADP-ribose) polymerase (PARP) as contributing factors in myocardial cell death. However, the interdependence of these factors in the intact, blood-perfused heart is not known. We therefore wanted to determine whether oxidant stress, mPTP opening, and PARP activity contribute to the same death pathway after myocardial I/R. A murine left anterior descending coronary artery (LAD) occlusion (30 minutes) and release (1 to 4 hours) model was employed. Experimental groups included controls and antioxidant-treated, mPTP-inhibited, or PARP-inhibited hearts. Antioxidant treatment prevented oxidative damage, mPTP opening, ATP depletion, and PARP activity, placing oxidant stress as the proximal death trigger. Genetic deletion of cyclophilin D (CypD(-/-)) prevented loss of total NAD(+) and PARP activity, and mPTP-mediated loss of mitochondrial function. Control hearts showed progressive mitochondrial depolarization and loss of ATP from 1.5 to 4 hours of reperfusion, but not outer mitochondrial membrane rupture. Neither genetic deletion of PARP-1 nor its pharmacological inhibition prevented the initial mPTP-mediated depolarization or loss of ATP, but PARP ablation did allow mitochondrial recovery by 4 hours of reperfusion. These results indicate that oxidant stress, the mPTP, and PARP activity contribute to a single death pathway after I/R in the heart. PARP activation undermines cell survival by preventing mitochondrial recovery after mPTP opening early in reperfusion. This suggests that PARP-mediated prolongation of mitochondrial depolarization contributes significantly to cell death via an energetic crisis rather than by mitochondrial outer membrane rupture.

  8. Heart Protection by Combination Therapy with Esmolol and Milrinone at Late-Ischemia and Early Reperfusion

    Huang, Ming-He; Wu, Yewen; Nguyen, Vincent; Rastogi, Saurabh; McConnell, Bradley K.; Wijaya, Cori; Uretsky, Barry F.; Poh, Kian-Keong; Tan, Huay-Cheem; Fujise, Kenichi

    2011-01-01

    Introduction The present study determined whether late-ischemia/early reperfusion therapy with the β1-adrenergic receptor (AR) blocker esmolol and phosphodiesterase III inhibitor milrinone reduced left ventricular (LV) myocardial infarct size (IS). Methods and Results In an ischemia/reperfusion rat model (30-min ischemia/4-hr reperfusion), esmolol, milrinone or esmolol + milrinone were intravenous (IV) infused over 10 min (from the last 5min of ischemia to the first 5min of reperfusion). LV-I...

  9. Antiarrhythmic effect of heat adaptation in ischemic and reperfusion injury to the heart.

    Monastyrskaya, E A; Belkina, L M; Manukhina, E B; Malyshev, I Yu

    2007-01-01

    Study on a model of 6-day dosed adaptation to heat in rats showed that this adaptation decreased the severity of cardiac arrhythmias during ischemic and reperfusion injury. The duration of arrhythmias decreased not only in the ischemic period, but also under conditions of reperfusion. Adaptation delayed the development of arrhythmias during ischemia, decreased the number of animals with late reperfusion arrhythmias, and improved recovery of the heart after ischemia and reperfusion.

  10. Anti neuroinflammatory effect of Vildagliptin in ischaemia-reperfusion induced cerebral infarction in normal and STZ induced type-II diabetic rats

    Kaleru Purnachander

    2016-03-01

    Full Text Available Diabetes is one of the major risk factor for cerebral ischemic stroke. Increased base line levels of oxidative stress in diabetes will lead to cerebral ischemic damage. In pathological conditions such as cerebral ischemia/reperfusion injury, free radicals cause oxidative stress and inflammation leading to increased injury of brain. Inflammation is one of the major pathological mechanisms involved in cerebral ischemia and reperfusion injury. Vildagliptin newer anti-diabetic drug of the class DPP-4 inhibitors is reported to have anti-inflammatory properties apart from its antihyperglycemic activity. Therefore the aim of the present study is to evaluate the anti-inflammatory effect of Vildagliptin against cerebral infarction induced ischemia reperfusion injury in normal and STZ induced diabetic Wistar rats. Cerebral infarction was induced by bilateral common carotid artery occlusion followed by 4 hr reperfusion. Percent infarction, inflammatory markers such as MPO, TNF-α, IL-6 and IL-10 were analysed. Treatment with Vildagliptin for a period of four weeks produced significant reduction in percent cerebral infarct volume. Vildagliptin at 10 mg/kg dose, showed significant reduction in markers like MPO, TNF-α, IL-6 and IL-1β in diabetic group when compared to normal group and in contrast significant increase in anti-inflammatory marker like IL-10 levels. Vildagliptin showed significant cerebroprotective effect by antiinflammatory mechanisms.

  11. Oxygen Therapy

    ... their breathing to dangerously low levels. Will I need oxygen when I sleep? Usually if you use supplemental oxygen during the ... your health care provider tells you you only need to use oxygen for exercise or sleep. Even if you feel “fine” off of your ...

  12. Oxidized tissue proteins after intestinal reperfusion injury in rats

    Schanaider Alberto

    2005-01-01

    Full Text Available PURPOSE: To analyse if the carbonyl proteins measurement could be validated as a method that allows the identification of an intestinal oxidative stress after ischemia and reperfusion injury. METHODS: Twenty-five male Wistar rats (n =21 weighting 200 to 250g were divided into three groups. Group I - control (n = 10. Group II - sham (n = 5 and Group III (n = 10 subjected to 60 minutes of intestinal ischemia and equal period of reperfusion. For this purpose it was clamped the superior mesenteric artery in its distal third. Histological changes and carbonyl protein levels were determined in the samples of all groups. In group III, samples of both normal and reperfused ileal segment were studied. RESULTS: All the reperfused segments showed mucosal and submucosal swelling and inflammatory infiltrate of the lamina propria. Levels of carbonyl protein rose in group III, including in the non-ischemic segments. The sensitivity and specificity of the carbonyl protein tissue levels were respectively 94% and 88%. CONCLUSION: The carbonyl protein method is a useful biologic marker of oxidative stress after the phenomenon of intestinal ischemia and reperfusion in rats. It was also noteworthy that the effects of oxidative stress could be seen far from the locus of the primary injury.

  13. Postconditioning attenuates acute intestinal ischemia–reperfusion injury

    Ilker Sengul

    2013-03-01

    Full Text Available The aim of this study was to test the hypothesis that postconditioning (POC would reduce the detrimental effects of the acute intestinal ischemia–reperfusion (I/R compared to those of the abrupt onset of reperfusion. POC has a protective effect on intestinal I/R injury by inhibiting events in the early minutes of reperfusion in rats. Twenty-four Wistar–Albino rats were subjected to the occlusion of superior mesenteric artery for 30 minutes, then reperfused for 120 minutes, and randomized to the four different modalities of POC: (1 control (no intervention; (2 POC-3 (three cycles of 10 seconds of reperfusion–reocclusion, 1 minute total intervention; (3 POC-6 (six cycles of 10 seconds of reperfusion–reocclusion, 2 minutes total intervention; and (4 sham operation (laparotomy only. The arterial blood samples [0.3 mL total creatine kinase (CK and 0.6 mL malondialdehyde (MDA] and the intestinal mucosal MDA were collected from each after reperfusion. POC, especially POC-6, was effective in attenuating postischemic pathology by decreasing the intestinal tissue MDA levels, serum total CK activity, inflammation, and total histopathological injury scores. POC exerted a protective effect on the intestinal mucosa by reducing the mesenteric oxidant generation, lipid peroxidation, and neutrophil accumulation. The six-cycle algorithm demonstrated the best protection.

  14. The Role of Tetrahydrobiopterin and Dihydrobiopterin in Ischemia/Reperfusion Injury When Given at Reperfusion

    Qian Chen

    2010-01-01

    Full Text Available Reduced nitric oxide (NO bioavailability and increased oxidative stress are major factors mediating ischemia/reperfusion (I/R injury. Tetrahydrobiopterin (BH4 is an essential cofactor of endothelial NO synthase (eNOS to produce NO, whereas dihydrobiopterin (BH2 can shift the eNOS product profile from NO to superoxide, which is further converted to hydrogen peroxide (H2O2 and cause I/R injury. The effects of BH4 and BH2 on oxidative stress and postreperfused cardiac functions were examined in ex vivo myocardial and in vivo femoral I (20 min/R (45 min models. In femoral I/R, BH4 increased NO and decreased H2O2 releases relative to saline control, and these effects correlated with improved postreperfused cardiac function. By contrast, BH2 decreased NO release relative to the saline control, but increased H2O2 release similar to the saline control, and these effects correlated with compromised postreperfused cardiac function. In conclusion, these results suggest that promoting eNOS coupling to produce NO and decrease H2O2 may be a key mechanism to restore postreperfused organ function during early reperfusion.

  15. Real-Time Fluorescence Measurements of ROS and [Ca2+] in Ischemic / Reperfused Rat Hearts: Detectable Increases Occur only after Mitochondrial Pore Opening and Are Attenuated by Ischemic Preconditioning.

    Andrienko, Tatyana; Pasdois, Philippe; Rossbach, Andreas; Halestrap, Andrew P

    2016-01-01

    Mitochondrial permeability transition pore (mPTP) opening is critical for ischemia / reperfusion (I/R) injury and is associated with increased [Ca2+] and reactive oxygen species (ROS). Here we employ surface fluorescence to establish the temporal sequence of these events in beating perfused hearts subject to global I/R. A bespoke fluorimeter was used to synchronously monitor surface fluorescence and reflectance of Langendorff-perfused rat hearts at multiple wavelengths, with simultaneous measurements of hemodynamic function. Potential interference by motion artefacts and internal filtering was assessed and minimised. Re-oxidation of NAD(P)H and flavoproteins on reperfusion (detected using autofluorescence) was rapid (t0.5 ROS increases during early reperfusion. However, two different fluorescent cytosolic ROS probes did detect ROS increases after 2-3 min of reperfusion, which was shown to be after initiation of mPTP opening. Cyclosporin A (CsA) and IP attenuated these responses and reduced infarct size. [Ca2+]i (monitored with Indo-1) increased progressively during ischemia, but dropped rapidly within 90 s of reperfusion when total mitochondrial [Ca2+] was shown to be increased. These early changes in [Ca2+] were not attenuated by IP, but substantial [Ca2+] increases were observed after 2-3 min reperfusion and these were prevented by both IP and CsA. Our data suggest that the major increases in ROS and [Ca2+] detected later in reperfusion are secondary to mPTP opening. If earlier IP-sensitive changes occur that might trigger initial mPTP opening they are below our limit of detection. Rather, we suggest that IP may inhibit initial mPTP opening by alternative mechanisms such as prevention of hexokinase 2 dissociation from mitochondria during ischemia.

  16. Astrocytic mitochondrial membrane hyperpolarization following extended oxygen and glucose deprivation.

    Andrej Korenić

    Full Text Available Astrocytes can tolerate longer periods of oxygen and glucose deprivation (OGD as compared to neurons. The reasons for this reduced vulnerability are not well understood. Particularly, changes in mitochondrial membrane potential (Δψ(m in astrocytes, an indicator of the cellular redox state, have not been investigated during reperfusion after extended OGD exposure. Here, we subjected primary mouse astrocytes to glucose deprivation (GD, OGD and combinations of both conditions varying in duration and sequence. Changes in Δψ(m, visualized by change in the fluorescence of JC-1, were investigated within one hour after reconstitution of oxygen and glucose supply, intended to model in vivo reperfusion. In all experiments, astrocytes showed resilience to extended periods of OGD, which had little effect on Δψ(m during reperfusion, whereas GD caused a robust Δψ(m negativation. In case no Δψ(m negativation was observed after OGD, subsequent chemical oxygen deprivation (OD induced by sodium azide caused depolarization, which, however, was significantly delayed as compared to normoxic group. When GD preceded OD for 12 h, Δψ(m hyperpolarization was induced by both GD and subsequent OD, but significant interaction between these conditions was not detected. However, when GD was extended to 48 h preceding OGD, hyperpolarization enhanced during reperfusion. This implicates synergistic effects of both conditions in that sequence. These findings provide novel information regarding the role of the two main substrates of electron transport chain (glucose and oxygen and their hyperpolarizing effect on Δψ(m during substrate deprivation, thus shedding new light on mechanisms of astrocyte resilience to prolonged ischemic injury.

  17. Interactions between Exosomes from Breast Cancer Cells and Primary Mammary Epithelial Cells Leads to Generation of Reactive Oxygen Species Which Induce DNA Damage Response, Stabilization of p53 and Autophagy in Epithelial Cells

    Dutta, Sujoy; Warshall, Case; Bandyopadhyay, Chirosree; Dutta, Dipanjan; Chandran, Bala

    2014-01-01

    Exosomes are nanovesicles originating from multivesicular bodies and are released by all cell types. They contain proteins, lipids, microRNAs, mRNAs and DNA fragments, which act as mediators of intercellular communications by inducing phenotypic changes in recipient cells. Tumor-derived exosomes have been shown to play critical roles in different stages of tumor development and metastasis of almost all types of cancer. One of the ways by which exosomes affect tumorigenesis is to manipulate the tumor microenvironments to create tumor permissive “niches”. Whether breast cancer cell secreted exosomes manipulate epithelial cells of the mammary duct to facilitate tumor development is not known. To address whether and how breast cancer cell secreted exosomes manipulate ductal epithelial cells we studied the interactions between exosomes isolated from conditioned media of 3 different breast cancer cell lines (MDA-MB-231, T47DA18 and MCF7), representing three different types of breast carcinomas, and normal human primary mammary epithelial cells (HMECs). Our studies show that exosomes released by breast cancer cell lines are taken up by HMECs, resulting in the induction of reactive oxygen species (ROS) and autophagy. Inhibition of ROS by N-acetyl-L-cysteine (NAC) led to abrogation of autophagy. HMEC-exosome interactions also induced the phosphorylation of ATM, H2AX and Chk1 indicating the induction of DNA damage repair (DDR) responses. Under these conditions, phosphorylation of p53 at serine 15 was also observed. Both DDR responses and phosphorylation of p53 induced by HMEC-exosome interactions were also inhibited by NAC. Furthermore, exosome induced autophagic HMECs were found to release breast cancer cell growth promoting factors. Taken together, our results suggest novel mechanisms by which breast cancer cell secreted exosomes manipulate HMECs to create a tumor permissive microenvironment. PMID:24831807

  18. Bortezomib-induced sensitization of malignant human glioma cells to vorinostat-induced apoptosis depends on reactive oxygen species production, mitochondrial dysfunction, Noxa upregulation, Mcl-1 cleavage, and DNA damage.

    Premkumar, Daniel R; Jane, Esther P; Agostino, Naomi R; DiDomenico, Joseph D; Pollack, Ian F

    2013-02-01

    Glioblastomas are invasive tumors with poor prognosis despite current therapies. Histone deacetylase inhibitors (HDACIs) represent a class of agents that can modulate gene expression to reduce tumor growth, and we and others have noted some antiglioma activity from HDACIs, such as vorinostat, although insufficient to warrant use as monotherapy. We have recently demonstrated that proteasome inhibitors, such as bortezomib, dramatically sensitized highly resistant glioma cells to apoptosis induction, suggesting that proteasomal inhibition may be a promising combination strategy for glioma therapeutics. In this study, we examined whether bortezomib could enhance response to HDAC inhibition in glioma cells. Although primary cells from glioblastoma multiforme (GBM) patients and established glioma cell lines did not show significant induction of apoptosis with vorinostat treatment alone, the combination of vorinostat plus bortezomib significantly enhanced apoptosis. The enhanced efficacy was due to proapoptotic mitochondrial injury and increased generation of reactive oxygen species. Our results also revealed that combination of bortezomib with vorinostat enhanced apoptosis by increasing Mcl-1 cleavage, Noxa upregulation, Bak and Bax activation, and cytochrome c release. Further downregulation of Mcl-1 using shRNA enhanced cell killing by the bortezomib/vorinostat combination. Vorinostat induced a rapid and sustained phosphorylation of histone H2AX in primary GBM and T98G cells, and this effect was significantly enhanced by co-administration of bortezomib. Vorinostat/bortezomib combination also induced Rad51 downregulation, which plays an important role in the synergistic enhancement of DNA damage and apoptosis. The significantly enhanced antitumor activity that results from the combination of bortezomib and HDACIs offers promise as a novel treatment for glioma patients. Copyright © 2011 Wiley Periodicals, Inc.

  19. Oxygen Therapy

    Bonnie Solmes

    2000-01-01

    Full Text Available LTOT is prescribed for people with chronic lung disease in whom there is a decrease in the ability of the lungs to supply enough oxygen to the body. The heart is obliged to pump faster to meet the body's oxygen requirements. This may place undue stress on the heart, resulting in palpitations, dizziness and fatigue. A low oxygen level in arterial blood is also harmful to the heart, the brain and the pulmonary blood vessels. Oxygen therapy is used to break this cycle. A person with low blood oxygen will often be able to accomplish more with less fatigue with the help of supplemental oxygen therapy. Shortness of breath is a mechanical problem resulting from the effects of chronic obstructive pulmonary disease. Oxygen therapy may or may not reduce shortness of breath, but it will help the lungs and heart to function with less stress.

  20. Effect of berberine on cell cycle arrest and cell survival during cerebral ischemia and reperfusion and correlations with p53/cyclin D1 and PI3K/Akt.

    Chai, Yu-Shuang; Hu, Jun; Lei, Fan; Wang, Yu-Gang; Yuan, Zhi-Yi; Lu, Xi; Wang, Xin-Pei; Du, Feng; Zhang, Dong; Xing, Dong-Ming; Du, Li-Jun

    2013-05-15

    Berberine acted as a natural medicine with multiple pharmacological activities. In the present study, we examined the effect of berberine against cerebral ischemia damage from cell cycle arrest and cell survival. Oxygen-glucose deprivation of PC12 cells and primary neurons, and carotid artery ligation in mice were used as in vitro and in vivo cerebral ischemia models. We found that the effect of berberine on cell cycle arrest during ischemia was mediated by decreased p53 and cyclin D1, increased phosphorylation of Bad (higher expression of p-Bad and higher ratio of p-Bad to Bad) and decreased cleavage of caspase 3. Meanwhile, berberine activated the PI3K/Akt pathway during the reperfusion, especially the phosphor-activation of Akt, to promote the cell survival. The neural protective effect of berberine was remained in the presence of inhibitor of mitogen-activated protein/extracellular signal-regulated kinase (MEK), but was suppressed by the inhibitors of PI3K and Akt. We demonstrated that berberine induced cell cycle arrest and cell survival to resist cerebral ischemia injury. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Radiation Damage in Scintillating Crystals

    Zhu Ren Yuan

    1998-01-01

    Crystal Calorimetry in future high energy physics experiments faces a new challenge to maintain its precision in a hostile radiation environment. This paper discusses the effects of radiation damage in scintillating crystals, and concludes that the predominant radiation damage effect in crystal scintillators is the radiation induced absorption, or color center formation, not the loss of the scintillation light yield. The importance of maintaining crystal's light response uniformity and the feasibility to build a precision crystal calorimeter under radiation are elaborated. The mechanism of the radiation damage in scintillating crystals is also discussed. While the damage in alkali halides is found to be caused by the oxygen or hydroxyl contamination, it is the structure defects, such as oxygen vacancies, cause damage in oxides. Material analysis methods used to reach these conclusions are presented in details.

  2. Different dose-dependent effects of ebselen in sciatic nerve ischemia-reperfusion injury in rats

    Filiz Ozyigit

    2015-08-01

    Full Text Available Ebselen is an organoselenium compound which has strong antioxidant and anti-inflammatory effects. We investigated the neuroprotective role of ebselen pretreatment in rats with experimental sciatic nerve ischemia-reperfusion (I/R injury. Adult male Sprague Dawley rats were divided into four groups (N = 7 in each group. Before sciatic nerve I/R was induced, ebselen was injected intraperitoneally at doses of 15 and 30 mg/kg. After a 2 h ischemia and a 3 h reperfusion period, sciatic nerve tissues were excised. Tissue levels of malondialdehyde (MDA and nitric oxide (NO, and activities of superoxide dismutase (SOD, glutathione peroxidase (GPx, and catalase (CAT were measured. Sciatic nerve tissues were also examined histopathologically. The 15 mg/kg dose of ebselen reduced sciatic nerve damage and apoptosis (P < 0.01, levels of MDA, NO, and inducible nitric oxide synthase (iNOS positive cells (P < 0.01, P < 0.05, respectively, and increased SOD, GPx, and CAT activities (P < 0.001, P < 0.01, P < 0.05, respectively compared with the I/R group that did not receive ebselen. Conversely, the 30 mg/kg dose of ebselen increased sciatic nerve damage, apoptosis, iNOS positive cells (P < 0.01, P < 0.05, P < 0.001 and MDA and NO levels (P < 0.05, P < 0.01 and decreased SOD, GPx, and CAT activities (P < 0.05 compared with the sham group. The results of this study suggest that ebselen may cause different effects depending on the dose employed. Ebselen may be protective against sciatic nerve I/R injury via antioxidant and antiapoptotic activities at a 15 mg/kg dose, conversely higher doses may cause detrimental effects.

  3. Levosimendan: a cardiovascular drug to prevent liver ischemia-reperfusion injury?

    Peter Onody

    Full Text Available INTRODUCTION: Temporary occlusion of the hepatoduodenal ligament leads to an ischemic-reperfusion (IR injury in the liver. Levosimendan is a new positive inotropic drug, which induces preconditioning-like adaptive mechanisms due to opening of mitochondrial KATP channels. The aim of this study was to examine possible protective effects of levosimendan in a rat model of hepatic IR injury. MATERIAL AND METHODS: Levosimendan was administered to male Wistar rats 1 hour (early pretreatment or 24 hours (late pretreatment before induction of 60-minute segmental liver ischemia. Microcirculation of the liver was monitored by laser Doppler flowmeter. After 24 hours of reperfusion, liver and blood samples were taken for histology, immuno- and enzyme-histochemistry (TUNEL; PARP; NADH-TR as well as for laboratory tests. Furthermore, liver antioxidant status was assessed and HSP72 expression was measured. RESULTS: In both groups pretreated with levosimendan, significantly better hepatic microcirculation was observed compared to respective IR control groups. Similarly, histological damage was also reduced after levosimendan administration. This observation was supported by significantly lower activities of serum ALT (p early = 0.02; p late = 0.005, AST (p early = 0.02; p late = 0.004 and less DNA damage by TUNEL test (p early = 0.05; p late = 0.034 and PAR positivity (p early = 0.02; p late = 0.04. Levosimendan pretreatment resulted in significant improvement of liver redox homeostasis. Further, significantly better mitochondrial function was detected in animals receiving late pretreatment. Finally, HSP72 expression was increased by IR injury, but it was not affected by levosimendan pretreatment. CONCLUSION: Levosimendan pretreatment can be hepatoprotective and it could be useful before extensive liver resection.

  4. CURRENT REPERFUSION THERAPY POSSIBILITIES IN MYOCARDIAL INFARCTION AND ISCHEMIC STROKE

    E. V. Konstantinova

    2015-01-01

    Full Text Available Myocardial infarction and ischemic stroke remain to be of the greatest medical and social importance because of their high prevalence, disability, and mortality rates. Intractable thrombotic occlusion of the respective artery leads to the formation of an ischemic lesion focus in the tissue of the heart or brain. Emergency reperfusion serves to decrease a necrotic focus, makes its formation reversible, and reduces patient death rates. The paper considers main reperfusion therapy lines: medical (with thrombolytic drugs and mechanical (with primary interventions one and their combination in treating patients with acute myocardial and cerebral ischemia. Each reperfusion procedure is discussed in view of its advantages, disadvantages, available guidelines, and possibilities of real clinical practice. Tenecteplase is assessed in terms of its efficacy, safety, and capacities for bolus administration, which allows its use at any hospital and at the pre-hospital stage. Prehospital thrombolysis permits reperfusion therapy to bring much closer to the patient and therefore aids in reducing time to reperfusion and in salvaging as much the myocardial volume as possible. The rapidest recovery of myocardial and cerebral perfusion results in a decreased necrotic area and both improved immediate and late prognosis. The results of randomized clinical trials studying the possibilities of the medical and mechanical methods to restore blood flow are analyzed in the context of evidence-based medicine. The reason why despite the available contraindications, limited efficiency, and the risk of hemorrhagic complications, thrombolytic therapy remains the method of choice for prehospital reperfusion, an alternative to primary percutaneous coronary intervention (PCI if it cannot be carried out in patients with myocardial infarction at the stated time, and the only treatment ischemic stroke treatment that has proven its efficiency and safety in clinical trials is under

  5. Far red/near infrared light-induced protection against cardiac ischemia and reperfusion injury remains intact under diabetic conditions and is independent of nitric oxide synthase

    Agnes eKeszler

    2014-08-01

    Full Text Available Far red/near-infrared light (NIR promotes a wide range of biological effects including tissue protection but whether and how NIR is capable of acutely protecting myocardium against ischemia and reperfusion injury in vivo is not fully elucidated. Our previous work indicates that NIR exposure immediately before and during early reperfusion protects the myocardium against infarction through mechanisms that are nitric oxide (NO-dependent. Here we tested the hypothesis that NIR elicits protection in a diabetic mouse model where other cardioprotective interventions such as pre- and postconditioning fail, and that the protection is independent of nitric oxide synthase (NOS. NIR reduced infarct size dose dependently. Importantly, NIR-induced protection was preserved in a diabetic mouse model (db/db and during acute hyperglycemia, as well as in endothelial NOS-/- mice and in wild type mice treated with NOS inhibitor L-NAME. In in vitro experiments NIR light liberates NO from nitrosyl hemoglobin (HbNO and nitrosyl myoglobin (MbNO in a wavelength (660-830 nm and dose-dependent manner. Irradiation at 660 nm yields the highest release of NO, while at longer wavelengths a dramatic decrease of NO release can be observed. Similar wavelength dependence was observed for the protection of mice against cardiac ischemia and reperfusion injury in vivo. NIR-induced NO release from deoxymyoglobin in the presence of nitrite mildly inhibits respiration of isolated mitochondria after hypoxia. In summary, NIR applied during reperfusion protects the myocardium against infarction in an NO dependent, but NOS-independent mechanisms, whereby mitochondria may be a target of NO released by NIR, leading to reduced reactive oxygen species generation during reperfusion. This unique mechanism preserves protection even during diabetes where other protective strategies fail.

  6. Triiodothyronine increases myocardial function and pyruvate entry into the citric acid cycle after reperfusion in a model of infant cardiopulmonary bypass

    Olson, Aaron K.; Bouchard, Bertrand; Ning, Xue-Han; Isern, Nancy; Rosiers, Christine Des

    2012-01-01

    Triiodothyronine (T3) supplementation improves clinical outcomes in infants after cardiac surgery using cardiopulmonary bypass by unknown mechanisms. We utilized a translational model of infant cardiopulmonary bypass to test the hypothesis that T3 modulates pyruvate entry into the citric acid cycle (CAC), thereby providing the energy support for improved cardiac function after ischemia-reperfusion (I/R). Neonatal piglets received intracoronary [2-13Carbon(13C)]pyruvate for 40 min (8 mM) during control aerobic conditions (control) or immediately after reperfusion (I/R) from global hypothermic ischemia. A third group (I/R-Tr) received T3 (1.2 μg/kg) during reperfusion. We assessed absolute CAC intermediate levels and flux parameters into the CAC through oxidative pyruvate decarboxylation (PDC) and anaplerotic carboxylation (PC) using [2-13C]pyruvate and isotopomer analysis by gas and liquid chromatography-mass spectrometry and 13C-nuclear magnetic resonance spectroscopy. When compared with I/R, T3 (group I/R-Tr) increased cardiac power and oxygen consumption after I/R while elevating flux of both PDC and PC (∼4-fold). Although neither I/R nor I/R-Tr modified absolute CAC levels, T3 inhibited I/R-induced reductions in their molar percent enrichment. Furthermore, 13C-labeling of CAC intermediates suggests that T3 may decrease entry of unlabeled carbons at the level of oxaloacetate through anaplerosis or exchange reaction with asparate. T3 markedly enhances PC and PDC fluxes, thereby providing potential substrate for elevated cardiac function after reperfusion. This T3-induced increase in pyruvate fluxes occurs with preservation of the CAC intermediate pool. Our labeling data raise the possibility that T3 reduces reliance on amino acids for anaplerosis after reperfusion. PMID:22180654

  7. 14S,21R-dihydroxy-docosahexaenoic acid treatment enhances mesenchymal stem cell amelioration of renal ischemia/reperfusion injury.

    Tian, Haibin; Lu, Yan; Shah, Shraddha P; Wang, Quansheng; Hong, Song

    2012-05-01

    Bone marrow mesenchymal stem cells (MSCs) have shown potential to improve treatment of renal failure. The prohealing functions of MSCs have been found to be enhanced by treatment with the lipid mediator, 14S,21R-dihydroxy-docosa4Z,7Z,10Z,12E,16Z,19Z-hexaenoic acid (14S,21R-diHDHA). In this article, using a murine model of renal ischemia/reperfusion (I/R) injury, we found that treatment with 14S,21R-diHDHA enhanced MSC amelioration of renal I/R injury. Treated MSCs more efficiently inhibited I/R-induced elevation of serum creatinine levels, reduced renal tubular cell death, and inhibited infiltration of neutrophils, macrophages, and dendritic cells in kidneys. Conditioned medium from treated MSCs reduced the generation of tumor necrosis factor-α and reactive oxygen species by macrophages under I/R conditions. Infusion of treated MSCs more efficiently reduced I/R-damage to renal histological structures compared with untreated MSCs (injury score: 7.9±0.4 vs. 10.5±0.5). Treated MSCs were resistant to apoptosis in vivo when transplanted under capsules of I/R-injured kidneys (active caspase-3+ MSCs: 4.2%±2.8% vs. 11.7%±2.4% of control) and in vitro when cultured under I/R conditions. Treatment with 14S,21R-diHDHA promoted viability of MSCs through a mechanism involving activation of the phosphoinositide 3-kinase -Akt signaling pathway. Additionally, treatment of MSCs with 14S,21R-diHDHA promoted secretion of renotrophic hepatocyte growth factor and insulin growth factor-1. Similar results were obtained when 14S,21RdiHDHA was used to inhibit apoptosis of human MSCs (hMSCs) and to increase the generation of renotrophic cytokines from hMSCs. These findings provide a lead for new strategies in the treatment of acute kidney injury with MSCs.

  8. Milrinone and levosimendan administered after reperfusion improve myocardial stunning in swine.

    Shibata, Itsuko; Cho, Sungsam; Yoshitomi, Osamu; Ureshino, Hiroyuki; Maekawa, Takuji; Hara, Tetsuya; Sumikawa, Koji

    2013-02-01

    We assessed the effect of milrinone application timing after reperfusion against myocardial stunning as compared with levosimendan in swine. Furthermore, we examined the role of p38 mitogen-activated protein kinase (p38 MAPK) in the milrinone-induced cardioprotection. All swine were subjected to 12-minutes ischemia followed by 90-minutes reperfusion to generate stunned myocardium. Milrinone or levosimendan was administered intravenously either for 20 minutes starting just after reperfusion or for 70 minutes starting 20 minutes after reperfusion. In another group, SB203580, a selective p38 MAPK inhibitor, was administered with and without milrinone. Regional myocardial contractility was assessed by percent segment shortening (%SS). Milrinone starting just after reperfusion, but not starting 20 minutes after reperfusion, improved %SS at 30, 60, and 90 minutes after reperfusion compared with that in the control group. SB203580 abolished the beneficial effect of milrinone. On the other hand, levosimendan starting 20 minutes after reperfusion, but not for 20 minutes starting just after reperfusion, improved %SS at 60 and 90 minutes after reperfusion. Milrinone should be administered just after reperfusion to protect myocardial stunning through p38 MAPK, whereas levosimendan improvement of contractile function could be mainly dependent on its positive inotropic effect.

  9. Determinants of myocardial hemorrhage after coronary reperfusion in the anesthetized dog

    Higginson, L.A.J.; White, F.; Heggtveit, H.A.; Sanders, T.M.; Bloor, C.M.; Covell, J.W.

    1982-01-01

    Intramyocardial hemorrhage often occurs with reperfusion in experimental acute myocardial infarction and is thought to be associated with extension of necrosis. To determine if hemorrhage was associated with extension of necrosis, 10 anesthetized dogs were reperfused after 6 hours of circumflex coronary artery occlusion and 10 others had control occlusion with no reperfusion. Fifteen of the 20 reperfused dogs had gross hemorrhage and none of the control dogs did. In 12 reperfused and 10 control dogs, radioactive microspheres were injected after coronary occlusion to quantitate collateral flow and in the reperfusion group microspheres were injected to quantitate reflow. Complete flow data were available in eight reperfused and 10 analyzed for hemorrhage, collateral flow and creatine kinase activity. Serial microscopic examination was performed in eight additional dogs reperfused after 6 hours to determine if hemorrhage occurs into otherwise microscopically normal myocardium. Pathologic examination indicatd that hemorrhage did not occur into otherwise microscopically normal myocardium. These studies indicate that hemorrhage or reperfusion is associated with severe myocardial necrosis and markedly depressed flow before reperfusion and this occurs only into myocardium already markedly compromised at the time of reperfusion

  10. Pretreatment with remifentanil protects against the reduced-intestinal contractility related to the ischemia and reperfusion injury in rat

    Hale Sayan-Ozacmak

    2015-12-01

    Full Text Available BACKGROUND AND OBJECTIVES: Serious functional and structural alterations of gastrointestinal tract are observed in failure of blood supply, leading to gastrointestinal dismotility. Activation of opioid receptors provides cardioprotective effect against ischemia-reperfusion (I/R injury. The aim of the present study was to determine whether or not remifentanil could reduce I/R injury of small intestine. METHODS: Male Wistar Albino rats were subjected to mesenteric ischemia (30 min followed by reperfusion (3 h. Four groups were designed: sham control; remifentanil alone; I/R control; and remifentanil + I/R. Animals in remifentanil + I/R group were subjected to infusion of remifentanil (2 ug kg-1 min-1 for 60 min, half of which started before inducing ischemia. Collecting the ileum tissues, evaluation of damage was based on contractile responses to carbachol, levels of lipid peroxidation and neutrophil infiltration, and observation of histopathological features in intestinal tissue. RESULTS: Following reperfusion, a significant decrease in carbachol-induced contractile response, a remarkable increase in both lipid peroxidation and neutrophil infiltration, and a significant injury in mucosa were observed. An average contractile response of remifentanil + I/R group was significantly different from that of the I/R group. Lipid peroxidation and neutrophil infiltration were also significantly suppressed by the treatment. The tissue samples of the I/R group were grade 4 in histopathological evaluation. In remifentanil + I/R group, on the other hand, the mucosal damage was moderate, staging as grade 1. CONCLUSIONS: The pretreatment with remifentanil can attenuate the intestinal I/R injury at a remarkable degree possibly by lowering lipid peroxidation and leukocyte infiltration.

  11. KCNMA1 encoded cardiac BK channels afford protection against ischemia-reperfusion injury.

    Ewa Soltysinska

    Full Text Available Mitochondrial potassium channels have been implicated in myocardial protection mediated through pre-/postconditioning. Compounds that open the Ca2+- and voltage-activated potassium channel of big-conductance (BK have a pre-conditioning-like effect on survival of cardiomyocytes after ischemia/reperfusion injury. Recently, mitochondrial BK channels (mitoBKs in cardiomyocytes were implicated as infarct-limiting factors that derive directly from the KCNMA1 gene encoding for canonical BKs usually present at the plasma membrane of cells. However, some studies challenged these cardio-protective roles of mitoBKs. Herein, we present electrophysiological evidence for paxilline- and NS11021-sensitive BK-mediated currents of 190 pS conductance in mitoplasts from wild-type but not BK-/- cardiomyocytes. Transmission electron microscopy of BK-/- ventricular muscles fibres showed normal ultra-structures and matrix dimension, but oxidative phosphorylation capacities at normoxia and upon re-oxygenation after anoxia were significantly attenuated in BK-/- permeabilized cardiomyocytes. In the absence of BK, post-anoxic reactive oxygen species (ROS production from cardiomyocyte mitochondria was elevated indicating that mitoBK fine-tune the oxidative state at hypoxia and re-oxygenation. Because ROS and the capacity of the myocardium for oxidative metabolism are important determinants of cellular survival, we tested BK-/- hearts for their response in an ex-vivo model of ischemia/reperfusion (I/R injury. Infarct areas, coronary flow and heart rates were not different between wild-type and BK-/- hearts upon I/R injury in the absence of ischemic pre-conditioning (IP, but differed upon IP. While the area of infarction comprised 28±3% of the area at risk in wild-type, it was increased to 58±5% in BK-/- hearts suggesting that BK mediates the beneficial effects of IP. These findings suggest that cardiac BK channels are important for proper oxidative energy supply of

  12. Albumin infusion after reperfusion prevents gut ischemia-reperfusion-induced gut-associated lymphoid tissue atrophy.

    Ikezawa, Fumie; Fukatsu, Kazuhiko; Moriya, Tomoyuki; Maeshima, Yoshinori; Okamoto, Koichi; Hara, Etsuko; Hiraide, Hoshio; Compher, Charlene W

    2006-01-01

    Our recent study clarified that gut ischemia-reperfusion (I/R) causes gut-associated lymphoid tissue (GALT) mass atrophy, a possible mechanism for increased morbidity of infectious complications after severe surgical insults. Because albumin administration reportedly reduces hemorrhagic shock-induced lung injury, we hypothesized that albumin treatment prevents GALT atrophy due to gut I/R. Male mice (n = 37) were randomized to albumin, normal saline, and sham groups. All groups underwent jugular vein catheter insertion. The albumin and normal saline groups underwent 75-minute occlusion of the superior mesenteric artery. During gut ischemia, all mice received normal saline infusions at 1.0 mL/h. The albumin group was given 5% bovine serum albumin in normal saline at 1.0 mL/h for 60 minutes after reperfusion, whereas the normal saline group received 0.9% sodium chloride at 1.0 mL/h. The sham group underwent laparotomy only. Mice were killed on day 1 or 7, and the entire small intestine was harvested. GALT lymphocytes were isolated and counted. Their phenotypes (alphabetaTCR, gammadeltaTCR, CD4, CD8, B220) were determined by flow cytometry. On day 1, the gut I/R groups showed significantly lower total lymphocyte and B cell numbers in Peyer's patches and the lamina propria than the sham group. However, the albumin infusion partially but significantly restored these cell numbers. On day 7, there were no significant differences in any of the parameters measured among the 3 groups. Albumin infusion after a gut ischemic insult may maintain gut immunity by preventing GALT atrophy.

  13. Effects of Ascorbic Acid, Alpha-Tocopherol and Allopurinol on Ischemia-Reperfusion Injury in Rabbit Skeletal Muscle: An Experimental Study

    Bilgehan Erkut

    2007-01-01

    , but no significant as statistically. Also amount of cellular injury in group II, III, and IV were lower than group I. Conclusions Antioxidant medication may help lowering ischemia reperfusion injury. In our study, all drug medications are shown to be able to have an effective role for preventing ischemia reperfusion injury. Moreover, ascorbic acide + alpha-tocopherol + allopurinol group (group IV may have a beneficial effect to decrease the local and systemic damage due to ischemia-reperfusion injury.

  14. Effects of Ascorbic Acid, Alpha-Tocopherol and Allopurinol on Ischemia-Reperfusion Injury in Rabbit Skeletal Muscle: An Experimental Study

    Bilgehan Erkut

    2007-01-01

    , but no significant as statistically. Also amount of cellular injury in group II, III, and IV were lower than group I.Conclusions: Antioxidant medication may help lowering ischemia reperfusion injury. In our study, all drug medications are shown to be able to have an effective role for preventing ischemia reperfusion injury. Moreover, ascorbic acide + alphatocopherol + allopurinol group (group IV may have a benefi cial effect to decrease the local and systemic damage due to ischemia-reperfusion injury.

  15. Testicular reperfusion injury, post ligation of the spermatic cord in ...

    This experiment was aimed at investigating the level of tissue regeneration following sanguineous reperfusion post ligation of the spermatic cord in dogs. A total of 5 adult Nigerian local dogs conditioned for 3 weeks, laboratorily evaluated twice weekly prior to surgery were maintained for 1month. Dogs were aseptically ...

  16. Mobilisation of satellite cells following ischaemia and reperfusion in ...

    Objective. To describe the morphological and morphometric features of activated skeletal muscle satellite cells in primates, using an ischaemic reperfusion model. Setting. The study was undertaken at the Biomedical Resource Centre and the Electron Microscopy Unit of the University of KwaZulu-Natal. Interventions.

  17. [Correction of a reperfusion dysfunction in acute intestinal obstruction].

    Bagnenko, S F; Sinenchenko, G I; Kurygin, A A; Chupris, V G

    2008-01-01

    An analysis of experimental investigations carried out in 32 dogs and 30 rabbits and laboratory data of 242 patients has shown that the application of antioxidant and antihypoxic medicines decrease reperfusion lesions and endotoxicosis in operative treatment of acute intestinal obstruction.

  18. The sterile immune response during hepatic ischemia/reperfusion

    van Golen, Rowan F.; van Gulik, Thomas M.; Heger, Michal

    2012-01-01

    Hepatic ischemia and reperfusion elicits an immune response that lacks a microbial constituent yet poses a potentially lethal threat to the host. In this sterile setting, the immune system is alarmed by endogenous danger signals that are release by stressed and dying liver cells. The detection of

  19. Short communication:Intestinal Ischaemia-Reperfusion Injury and ...

    This study investigates the effect of intestinal ischaemia-reperfusion (IIR) injury on semen characteristics in WAD bucks. Six healthy adult male ... Many of the abnormalities involved midpiece and tail abnormalities which are very vital to propulsion and may cause an inability of the sperm cells to fertilize. This hitherto silent ...

  20. Gene Expression ‏‏‏‏Profiles of BAD and Bcl-xL in the CA1 Region of the Hippocampus Following Global Ischemic/Reperfusion and FK-506 Administration.

    Badr, Ramak; Hashemi, Mehrdad; Javadi, Gholamreza; Movafagh, Abolfazl; Mahdian, Reza

    2015-12-01

    The hippocampus is a tiny nub in the mammalian brain that is involved in forming, organizing, and storing memories. Global cerebral ischemia (GCI) and reperfusion induced apoptosis lead to cell injury and death. FK-506 is a strong immunosuppressant drug that has neuroprotective effects on the hypoxic-ischemic effects of brain damage. BAD and Bcl-xL are pro-apoptotic and anti-apoptotic genes, respectively. These genes belong to The B-cell lymphoma-2 (Bcl-2) family. In this study, we assessed the neurotrophic properties of FK-506 on expression of the BAD and Bcl-xL genes in the hippocampus following global ischemia and reperfusion. In the present experimental study, adult male Wistar rats were obtained and housed under standard conditions in the Tehran University of Medical Science in Iran. Rats were equally distributed in groups of three among the following groups: normal control, treated-1 (ischemia/reperfusion), and treated-2 (ischemia/reperfusion followed by FK-506). Global ischemia was induced for animals in the treated-1 and treated-2 groups. In treated-2, two doses of FK-506 were injected: one dose as an IV injection immediately after reperfusion and another as an intra-peritoneal (IP) injection after 48 hours. Then, the hippocampus tissue was removed after anaesthetizing the rats. RNA was isolated, cDNA was synthesized, and real-time PCR was performed. Finally, the obtained data were analyzed statistically (P value ˂ 0.05). The quantitative results of real-time PCR show that the mRNA expression ratio of Bcl-xL down-regulated was 0.75 ± 0.06 in the ischemia/reperfusion group versus 1.57 ± 0.09 in the control group (P value BAD up-regulated in the ischemia/reperfusion + FK506 group was 3.65 ± 0.49 compared to Normal control (1.39 ± 0.09) and Ischemia/reperfusion + FK506 was 1.09 ± 0.20 (P value BAD /Bcl-xL) confirmed that expression of the pro-apoptotic gene significantly decreased (P value ˂ 0.001) under the ischemia/reperfusion condition. In contrast

  1. Oxidative Damage in Erythrocytes During Cold Storage With Organ Preservation Solution

    MEMMEDOĞLU, Akif B.

    1999-01-01

    It is known that erythrocyte aggregation in renal tissue during preserva-tion is cause of microcirculation defects in the reperfusion period. The aim of our study is to investigate oxidative damage in erythrocytes relative to the time of cold ischemia during organ preservation and relationship between lipid peroxidation and development of these damages. In experiments with a rabbit model, explanted kidneys were exposed to perfusion and 96 hours preservation with Euro-Collins (EC) in the 1...

  2. Hydrogen sulfide reduces neutrophil recruitment in hind-limb ischemia-reperfusion injury in an L-selectin and ADAM-17 dependent manner

    Ball, Carissa J.; Reiffel, Alyssa J.; Chintalapani, Sathvika; Kim, Minsoo; Spector, Jason A.; King, Michael R.

    2012-01-01

    Background Reperfusion following ischemia leads to neutrophil recruitment injured tissue. Selectins and β2 integrins regulate neutrophil interaction with the endothelium during neutrophil rolling and firm adhesion. Excessive neutrophil infiltration into tissue is thought to contribute to IRI damage. NaHS mitigates the damage caused by ischemia-reperfusion injury (IRI). This study's objective was to determine the effect of hydrogen sulfide (NaHS) on neutrophil adhesion receptor expression. Methods Human neutrophils were either left untreated or incubated in 20 μM NaHS, and/or 50 μg/mL pharmacological ADAM-17 inhibitor TAPI-0; activated by IL-8, fMLP, or TNF-α; and labeled against PSGL-1, LFA-1, Mac-1 α, L-selectin and β2 integrin epitopes CBRM1/5 or KIM127 for flow cytometry. Cohorts of 3 C57BL/6 mice received an intravenous dose of saline vehicle, or 20 μM NaHS with or without 50 μg/mL TAPI-0 before unilateral tourniquet induced hind-limb ischemia for 3 hours followed by 3 hours of reperfusion. Bilateral gastrocnemius muscles were processed for histology before neutrophil infiltration quantification. Results NaHS treatment significantly increased L-selectin shedding from human neutrophils following activation by fMLP and IL-8 in an ADAM-17 dependent manner. Mice treated with NaHS to raise bloodstream concentration by 20 μM prior to ischemia or reperfusion showed a significant reduction in neutrophil recruitment into skeletal muscle tissue following tourniquet-induced hindlimb IRI. Conclusions NaHS administration results in the downregulation of L-selectin expression in activated human neutrophils. This leads to a reduction in neutrophil extravasation and tissue infiltration and may partially account for the protective effects of NaHS seen in the setting of IRI. PMID:23446563

  3. Distribution of carbon flux within fatty acid utilization during myocardial ischemia and reperfusion

    Nellis, S.H.; Liedtke, A.J.; Renstrom, B.

    1991-01-01

    Twenty-nine intact, working pig hearts were extracorporeally perfused and divided into two study groups (16 Aerobic and 13 Ischemic/Reflow hearts). Step function, equilibrium labeling with [14C]palmitate was used to develop uptake and washout curves of radioactive fatty acid products contained in coronary effluent during either aerobic perfusion or reperfusion after ischemia (60% reduction in left anterior descending coronary flow for 30 minutes). Left anterior descending control flows were slightly overperfused in Aerobic hearts (18% higher than in Ischemic/Reflow hearts); otherwise, circumflex and right coronary flows, left ventricular pressure, and serum fatty acids and blood sugar levels were comparable between groups. As expected in Ischemic/Reflow hearts, recovery of regional systolic shortening and myocardial oxygen consumption in reperfusion was only modestly impaired (-20% and -19%, respectively, not significant and p less than 0.011 compared with preischemic values, not significant from Aerobic hearts). The only significant metabolized product to be released from labeled fatty acid utilization in either group was 14CO2. A smaller fatty acid pool also was measured and accounted for by that contained in the coronary intravascular volume. The authors could determine no significant back diffusion of fatty acids from myocardium in either perfusion condition. Uptake time constants of the early phase of 14CO2 production also were virtually identical in both groups (19.9 ± 3.2 versus 16.7 ± 3.2 minutes in Aerobic and Ischemic/Reflow hearts, respectively) and strongly correlated with hemodynamics as described by heart rate. In washout studies, tissue radioactivity in the aqueous soluble and fatty acid pools declined in both study groups, and counts in complex lipids and cholesterol/cholesteryl esters remained steady, whereas those in triacylglycerols varied

  4. Effects of propionyl-L-carnitine on ischemia-reperfusion injury in hamster cheek pouch microcirculation.

    Lapi, Dominga; Sabatino, Lina; Altobelli, Giovanna Giuseppina; Mondola, Paolo; Cimini, Vincenzo; Colantuoni, Antonio

    2010-01-01

    Propionyl-l-carnitine (pLc) exerts protective effects in different experimental models of ischemia-reperfusion (I/R). The aim of the present study was to assess the effects of intravenously and topically applied pLc on microvascular permeability increase induced by I/R in the hamster cheek pouch preparation. The hamster cheek pouch microcirculation was visualized by fluorescence microscopy. Microvascular permeability, leukocyte adhesion to venular walls, perfused capillary length, and capillary red blood cell velocity (V(RBC)) were evaluated by computer-assisted methods. E-selectin expression was assessed by in vitro analysis. Lipid peroxidation and reactive oxygen species (ROS) formation were determined by thiobarbituric acid-reactive substances (TBARS) and 2'-7'-dichlorofluorescein (DCF), respectively. In control animals, I/R caused a significant increase in permeability and in the leukocyte adhesion in venules. Capillary perfusion and V(RBC) decreased. TBARS levels and DCF fluorescence significantly increased compared with baseline. Intravenously infused pLc dose-dependently prevented leakage and leukocyte adhesion, preserved capillary perfusion, and induced vasodilation at the end of reperfusion, while ROS concentration decreased. Inhibition of nitric oxide synthase prior to pLc caused vasoconstriction and partially blunted the pLc-induced protective effects; inhibition of the endothelium-derived hyperpolarizing factor (EDHF) abolished pLc effects. Topical application of pLc on cheek pouch membrane produced the same effects as observed with intravenous administration. pLc decreased the E-selectin expression. pLc prevents microvascular changes induced by I/R injury. The reduction of permeability increase could be mainly due to EDHF release induce vasodilatation together with NO. The reduction of E-selectin expression prevents leukocyte adhesion and permeability increase.

  5. Effects of propionyl-L-carnitine on ischemia-reperfusion injury in hamster cheek pouch microcirculation.

    Dominga Lapi

    2010-10-01

    Full Text Available Background and Purpose Propionyl-L-carnitine (pLc exerts protective effects in different experimental models of ischemia-reperfusion (I/R. The aim of the present study was to assess the effects of intravenously and topically applied pLc on microvascular permeability increase induced by I/R in the hamster check pouch preparation. Methods The hamster check pouch microcirculation was visualized by fluorescence microscopy. Microvascular permeability, leukocyte adhesion to venular walls, perfused capillary length and capillary red blood cell velocity (VRBC were evaluated by computer-assisted methods. E-selectin expression was assessed by in vitro analysis. Lipid peroxidation and reactive oxygen species (ROS formation were determined by thiobarbituric acid-reactive substances (TBARS and 2’-7’-dichlorofluorescein (DCF, respectively. Results In control animals, I/R caused a significant increase in permeability and in the leukocyte adhesion in venules. Capillary perfusion and VRBC decreased. TBARS levels and DCF fluorescence significantly increased compared with baseline. Intravenously infused pLc dose-dependently prevented leakage and leukocyte adhesion, preserved capillary perfusion and induced vasodilation at the end of reperfusion, while ROS concentration decreased. Inhibition of nitric oxide synthase prior to pLc caused vasoconstriction and partially blunted the pLc-induced protective effects; inhibition of the endothelium-derived hyperpolarizing factor (EDHF abolished pLc effects. Topical application of pLc on check pouch membrane produced the same effects as observed with intravenous administration. pLc decreased the E-selectin expression. Conclusions pLc prevents microvascular changes induced by I/R injury. The reduction of permeability increase could be mainly due to EDHF release induce vasodilatation together with NO. The reduction of E-selectin expression prevents leukocyte adhesion and permeability increase.

  6. Britanin Ameliorates Cerebral Ischemia-Reperfusion Injury by Inducing the Nrf2 Protective Pathway.

    Wu, Guozhen; Zhu, Lili; Yuan, Xing; Chen, Hao; Xiong, Rui; Zhang, Shoude; Cheng, Hao; Shen, Yunheng; An, Huazhang; Li, Tiejun; Li, Honglin; Zhang, Weidong

    2017-10-10

    Oxidative stress is considered the major cause of tissue injury after cerebral ischemia. The nuclear factor erythroid 2-related factor 2 (Nrf2) pathway is one of the most important defensive mechanisms against oxidative stresses and has been confirmed as a target for stroke treatment. Thus, we desired to find new Nrf2 activators and test their neuronal protective activity both in vivo and in vitro. The herb-derived compound, Britanin, is a potent inducer of the Nrf2 system. Britanin can induce the expression of protective enzymes and reverse oxygen-glucose deprivation, followed by reperfusion (OGD-R)-induced neuronal injury in primary cortical neurons in vitro. Furthermore, the administration of Britanin significantly ameliorated middle cerebral artery occlusion-reperfusion (MCAO-R) insult in vivo. We report here the crystal structure of the complex of Britanin and the BTB domain of Keap1. Britanin selectively binds to a conserved cysteine residue, cysteine 151, of Keap1 and inhibits Keap1-mediated ubiquitination of Nrf2, leading to induction of the Nrf2 pathway. Britanin is a potent inducer of Nrf2. The complex crystal structure of Britanin and the BTB domain of Keap1 help clarify the mechanism of Nrf2 induction. Britanin was proven to protect primary cortical neurons against OGD-R-induced injury in an Nrf2-dependant way. Additionally, Britanin had excellent cerebroprotective effect in an MCAO-R model. Our results demonstrate that the natural product Britanin with potent Nrf2-activating and neural protective activities both in vitro and in vivo could be developed into a cerebroprotective therapeutic agent. Antioxid. Redox Signal. 27, 754-768.

  7. Modification of radiation sensitivity: the oxygen effect

    Quintiliani, M.

    1979-01-01

    Four fundamental aspects of the oxygen effect in radiobiology are reviewed, with emphasis on single cell systems: (1) Radiosensitivity in relation to oxygen concentration. In many biological systems, this relationship is remarkably well represented by the well-known Howard-Flanders/Alper formula. Often, however, the degree of uncertainty associated with the estimation of the value of K in the formula is fairly high. Recent data on V79-753B cells indicate a biphasic influence of oxygen concentration on radiosensitivity that cannot be described in terms of the Howard-Flanders/Alper model. (2) The oxygen effect in relation to survival level. The influence of very low oxygen concentrations on the shoulder of the survival curves of irradiated cells is still controversial. Also, the oxygen dependence of repair processes for sublethal and potentially lethal damage need to be better defined. (3) Time-scale of the oxygen effect. All the experimental data obtained with the use of fast techniques indicate that the time scale of the oxygen effect is consistent with that of free radical reactions. This appears to be compatible with the hypothesis that oxygen acts by fixation of a radiation-induced reversible damage. The existence of two types of damage with different rates of decay is suggested, both in bacterial and mammalian cells. (4) Molecular mechanisms of the oxygen effect. In spite of the very large literature on this subject, the identification of the detailed molecular mechanisms of the oxygen effect must still be considered goals for future research

  8. The effect of levosimendan on myocardial ischemia–reperfusion injury in streptozotocin-induced diabetic rats

    Hasan Ali Kiraz

    2015-12-01

    Full Text Available Objective: Ischemia/reperfusion (I/R injury is an important cause of myocardial damage by means of oxidative, inflammatory, and apoptotic mechanisms. The aim of the present study was to examine the potential cardio protective effects of levosimendan in a diabetic rat model of myocardial I/R injury. Methods: A total of 18 streptozotocin-induced diabetic Wistar Albino rats (55 mg/kg were randomly divided into three equal groups as follows: the diabetic I/R group (DIR in which myocardial I/R was induced following left thoracotomy, by ligating the left anterior descending coronary artery for 60 min, followed by 2 h of reperfusion; the diabetic I/R levosimendan group (DIRL, which underwent I/R by the same method while taking levosimendan intraperitoneal 12 µg kg−1; and the diabetic control group (DC which underwent sham operations without tightening of the coronary sutures. As a control group (C, six healthy age-matched Wistar Albino rats underwent sham operations similar to the DC group. Two hours after the operation, the rats were sacrificed and the myocardial tissue samples were examined by light microscopy for evidence of myonecrosis and inflammatory cell infiltration. Results: Myonecrosis findings were significantly different among groups (p=0.008. Myonecrosis was more pronounced in the DIR group compared with the C, DC, and DIRL groups (p=0.001, p=0.007 and p=0.037, respectively. Similarly, the degree of inflammatory cell infiltration showed significant difference among groups (p<0.0001. Compared with C, DC, and DIRL groups, the inflammatory cell infiltration was significantly higher among the DIR group (p<0.0001, p<0.0001, and p=0.020, respectively. Also, myocardial tissue edema was significantly different among groups (p=0.006. The light microscopic myocardial tissue edema levels were significantly higher in the DIR group than the C, DC, and DIRL groups (p=0.001, p=0.037, and p=0.014, respectively. Conclusion: Taken together, our data

  9. The effect of levosimendan on myocardial ischemia–reperfusion injury in streptozotocin-induced diabetic rats

    Kiraz, Hasan Ali; Poyraz, Fatih; Kip, Gülay; Erdem, Özlem; Alkan, Metin; Arslan, Mustafa; Özer, Abdullah; Şivgin, Volkan; Çomu, Faruk Metin

    2015-01-01

    Objective Ischemia/reperfusion (I/R) injury is an important cause of myocardial damage by means of oxidative, inflammatory, and apoptotic mechanisms. The aim of the present study was to examine the potential cardio protective effects of levosimendan in a diabetic rat model of myocardial I/R injury. Methods A total of 18 streptozotocin-induced diabetic Wistar Albino rats (55 mg/kg) were randomly divided into three equal groups as follows: the diabetic I/R group (DIR) in which myocardial I/R was induced following left thoracotomy, by ligating the left anterior descending coronary artery for 60 min, followed by 2 h of reperfusion; the diabetic I/R levosimendan group (DIRL), which underwent I/R by the same method while taking levosimendan intraperitoneal 12 µg kg−1; and the diabetic control group (DC) which underwent sham operations without tightening of the coronary sutures. As a control group (C), six healthy age-matched Wistar Albino rats underwent sham operations similar to the DC group. Two hours after the operation, the rats were sacrificed and the myocardial tissue samples were examined by light microscopy for evidence of myonecrosis and inflammatory cell infiltration. Results Myonecrosis findings were significantly different among groups (p=0.008). Myonecrosis was more pronounced in the DIR group compared with the C, DC, and DIRL groups (p=0.001, p=0.007 and p=0.037, respectively). Similarly, the degree of inflammatory cell infiltration showed significant difference among groups (p<0.0001). Compared with C, DC, and DIRL groups, the inflammatory cell infiltration was significantly higher among the DIR group (p<0.0001, p<0.0001, and p=0.020, respectively). Also, myocardial tissue edema was significantly different among groups (p=0.006). The light microscopic myocardial tissue edema levels were significantly higher in the DIR group than the C, DC, and DIRL groups (p=0.001, p=0.037, and p=0.014, respectively). Conclusion Taken together, our data indicate that

  10. Effect of Intervention in Mast Cell Function Before Reperfusion on Renal Ischemia-Reperfusion Injury in Rats

    Fei Tong

    2016-06-01

    Full Text Available Background/Aims: Mast cells are sparsely distributed in the kidneys under normal conditions; however, the number of mast cells increases dramatically during renal ischemia/reperfusion injury (RI/RI. When mast cells are stimulated, numerous mediators are released, and under pathological conditions, they produce a wide range of biological effects. The aim of this study was to investigate the effect of intervention in mast cell function before reperfusion on RI/RI. Methods: Sprague-Dawley (SD rats (n=50 were randomized into five groups: sham group, ischemia/reperfusion (I/R group, cromolyn sodium treatment group (CS+I/R group, ketotifen treatment group (K+I/Rgroup, and compound 48/80 treatment group (C+I/R group. I/R injury was induced by bilateral renal artery and vein occlusion for 45 min followed by 24 h of reperfusion. The agents were intravenously administered 5 min before reperfusion through the tail vein. The serum levels of blood urea nitrogen(BUN, serum creatinine (Scr and histamine and the kidney levels of malondialdehyde (MDA, superoxide dismutase (SOD, tumor necrosis factor α (TNF-α and interleukin-6 (IL-6 were assessed. The expression of intracellular adhesion molecule-1 (ICAM-1 in renal tissue was also measured. Results: I/R injury resulted in severe renal injury, as demonstrated by a large increase in injury scores; serum levels of BUN, Scr and histamine; and kidney levels of MDA, TNF-α, and IL-6; this was accompanied by reduced SOD activity and upregulated ICAM-1 expression. Treatment with cromolyn sodium or ketotifen markedly alleviated I/R-mediated kidney injury, whereas compound 48/80 further aggravated kidney injury. Conclusion: Intervention in mast cell activity prior to reperfusionhas a strong effect on RI/RI.

  11. The Role of Mitochondrial Reactive Oxygen Species in Cardiovascular Injury and Protective Strategies

    Danina M. Muntean

    2016-01-01

    Full Text Available Ischaemia/reperfusion (I/R injury of the heart represents a major health burden mainly associated with acute coronary syndromes. While timely coronary reperfusion has become the established routine therapy in patients with ST-elevation myocardial infarction, the restoration of blood flow into the previously ischaemic area is always accompanied by myocardial injury. The central mechanism involved in this phenomenon is represented by the excessive generation of reactive oxygen species (ROS. Besides their harmful role when highly generated during early reperfusion, minimal ROS formation during ischaemia and/or at reperfusion is critical for the redox signaling of cardioprotection. In the past decades, mitochondria have emerged as the major source of ROS as well as a critical target for cardioprotective strategies at reperfusion. Mitochondria dysfunction associated with I/R myocardial injury is further described and ultimately analyzed with respect to its role as source of both deleterious and beneficial ROS. Furthermore, the contribution of ROS in the highly investigated field of conditioning strategies is analyzed. In the end, the vascular sources of mitochondria-derived ROS are briefly reviewed.

  12. Role of eicosanoids and white blood cells in the beneficial effects of limited reperfusion after ischemia-reperfusion injury in skeletal muscle

    Anderson, R.J.; Cambria, R.A.; Dikdan, G.; Lysz, T.W.; Hobson, R.W. II

    1990-01-01

    Limiting the rate of reperfusion blood flow has been shown to be beneficial locally in models of ischemia-reperfusion injury. We investigated the effects of this on eicosanoids (thromboxane B2, 6-keto-PGF1 alpha, and leukotriene B4), white blood cell activation, and skeletal muscle injury as quantitated by triphenyltetrazolium chloride and technetium-99m pyrophosphate after ischemia-reperfusion injury in an isolated gracilis muscle model in 16 anesthetized dogs. One gracilis muscle in each dog was subjected to 6 hours of ischemia followed by 1 hour of limited reperfusion and then by a second hour of normal reperfusion. The other muscle was subjected to 6 hours of ischemia followed by 2 hours of normal reperfusion. Six dogs each were used as normal reperfusion controls (NR) and limited reperfusion controls (LR), with 5 dogs being treated with a thromboxane synthetase inhibitor (LR/TSI) and another five with a leukotriene inhibitor (LR/LI). LR in all three groups (LR, LR/TSI, and LR/LI) showed a benefit in skeletal muscle injury as measured by triphenyltetrazolim chloride and technetium-99m pyrophosphate when compared with NR. However, there was no significant difference between the groups with LR regarding eicosanoid levels and white blood cell activation when compared with NR. These results demonstrate that LR produces benefits by mechanisms other than those dependent upon thromboxane A2, prostacyclin, or white blood cell activation

  13. Enhancement of Na/K pump activity by chronic intermittent hypobaric hypoxia protected against reperfusion injury.

    Guo, Hui-Cai; Guo, Fang; Zhang, Li-Nan; Zhang, Rong; Chen, Qing; Li, Jun-Xia; Yin, Jian; Wang, Yong-Li

    2011-06-01

    Chronic intermittent hypobaric hypoxia (CIHH) has been shown to attenuate intracellular Na(+) accumulation and Ca(2+) overload during ischemia and reperfusion (I/R), both of which are closely related to the outcome of myocardial damage. Na/K pump plays an essential role in maintaining the equilibrium of intracellular Na(+) and Ca(2+) during I/R. It has been shown that enhancement of Na/K pump activity by ischemic preconditioning may be involved in the cardiac protection. Therefore, we tested whether Na/K pump was involved in the cardioprotection by CIHH. We found that Na/K pump current in cardiac myocytes of guinea pigs exposed to CIHH increased 1.45-fold. The K(1) and f(1), which reflect the portion of α(1)-isoform of Na/K pump, dramatically decreased or increased, respectively, in CIHH myocytes. Western blot analysis revealed that CIHH increased the protein expression of the α(1)-isoform by 76%, whereas the protein expression of the α(2)-isoform was not changed significantly. Na/K pump current was significantly suppressed in simulated I/R, and CIHH preserved the Na/K pump current. CIHH significantly improved the recovery of cell length and contraction during reperfusion. Furthermore, inhibition of Na/K pump by ouabain attenuated the protective effect afforded by CIHH. Collectively, these data suggest that the increase of Na/K pump activity following CIHH is due to the upregulating α(1)-isoform of Na/K pump, which may be one of the mechanisms of CIHH against I/R-induced injury.

  14. Role of TRPV1 channels in ischemia/reperfusion-induced acute kidney injury.

    Lan Chen

    Full Text Available OBJECTIVES: Transient receptor potential vanilloid 1 (TRPV1 -positive sensory nerves are widely distributed in the kidney, suggesting that TRPV1-mediated action may participate in the regulation of renal function under pathophysiological conditions. Stimulation of TRPV1 channels protects against ischemia/reperfusion (I/R-induced acute kidney injury (AKI. However, it is unknown whether inhibition of these channels is detrimental in AKI or not. We tested the role of TRPV1 channels in I/R-induced AKI by modulating these channels with capsaicin (TRPV1 agonist, capsazepine (TRPV1 antagonist and using Trpv1-/- mice. METHODS AND RESULTS: Anesthetized C57BL/6 mice were subjected to 25 min of renal ischemia and 24 hrs of reperfusion. Mice were pretreated with capsaicin (0.3 mg/kg body weight or capsazepine (50 mg/kg body weight. Capsaicin ameliorated the outcome of AKI, as measured by serum creatinine levels, tubular damage,neutrophil gelatinase-associated lipocalin (NGAL abundance and Ly-6B.2 positive polymorphonuclear inflammatory cells in injured kidneys. Neither capsazepine nor deficiency of TRPV1 did deteriorate renal function or histology after AKI. Measurements of endovanilloids in kidney tissue indicate that 20-hydroxyeicosatetraeonic acid (20-HETE or epoxyeicosatrienoic acids (EETs are unlikely involved in the beneficial effects of capsaicin on I/R-induced AKI. CONCLUSIONS: Activation of TRPV1 channels ameliorates I/R-induced AKI, but inhibition of these channels does not affect the outcome of AKI. Our results may have clinical implications for long-term safety of renal denervation to treat resistant hypertension in man, with respect to the function of primary sensory nerves in the response of the kidney to ischemic stimuli.

  15. The protective effect of SCR(15-18) on cerebral ischemia-reperfusion injury.

    Li, Shu; Xian, Jinhong; He, Li; Luo, Xue; Tan, Bing; Yang, Yongtao; Liu, Gaoke; Wang, Zhengqing

    2011-10-01

    Soluble complement receptor type 1 (sCR1), a potent inhibitor of complement activation, has been shown to protect brain cells against cerebral ischemic/reperfusion (CI/R) injury due to its decay-accelerating activity for C3/C5 convertase and co-factor activity for C3b/C4b degradation. However, the effect of short consensus repeats (SCRs) 15-18, one of active domains of sCR1 with high C3b/C4b degradability, has not been demonstrated. Here, we investigated the protective effect of recombinant SCR(15-18) protein in middle cerebral artery occlusion (MCAO)-induced focal CI/R injury. Recombinant SCR(15-18) protein was successfully expressed in Escherichia coli and refolded to its optimal bioactivity. Seventy-five Sprague-Dawley rats were randomly assigned into three groups: sham-operated group, CI/R group, and SCR(15-18)+CI/R group pretreated with 20 mg/kg SCR(15-18) protein. After 2 hours of MCAO and subsequent 24 hours of reperfusion, rats were evaluated for neurological deficits and cerebral infarction. Polymorphonuclear leukocyte accumulation, C3b deposition, and morphological changes in cerebral tissue were also estimated. SCR(15-18) pretreatment induced a 20% reduction of infarct size and an improvement of neurological function with 22·2% decrease of neurological deficit scores. Inhibition of cerebral neutrophils infiltration by SCR(15-18) was indicated from the reduction of myeloperoxidase activity in SCR(15-18)+CI/R rats. Decreased C3b deposition and improved morphological changes were also found in cerebral tissue of SCR(15-18)-treated rats. Our studies suggest a definitive moderately protective effect of SCR(15-18) against CI/R damage and provide preclinical experimental evidence supporting the possibility of using it as a small anti-complement therapeutic agent for CI/R injury therapy.

  16. Sevoflurane postconditioning improves myocardial mitochondrial respiratory function and reduces myocardial ischemia-reperfusion injury by up-regulating HIF-1.

    Yang, Long; Xie, Peng; Wu, Jianjiang; Yu, Jin; Yu, Tian; Wang, Haiying; Wang, Jiang; Xia, Zhengyuan; Zheng, Hong

    2016-01-01

    Sevoflurane postconditioning (SPostC) can exert myocardial protective effects similar to ischemic preconditioning. However, the exact myocardial protection mechanism by SPostC is unclear. Studies indicate that hypoxia-inducible factor-1 (HIF-1) maintains cellular respiration homeostasis by regulating mitochondrial respiratory chain enzyme activity under hypoxic conditions. This study investigated whether SPostC could regulate the expression of myocardial HIF-1α and to improve mitochondrial respiratory function, thereby relieving myocardial ischemia-reperfusion injury in rats. The myocardial ischemia-reperfusion rat model was established using the Langendorff isolated heart perfusion apparatus. Additionally, postconditioning was performed using sevoflurane alone or in combination with the HIF-1α inhibitor 2-methoxyestradiol (2ME2). The changes in hemodynamic parameters, HIF-1α protein expression levels, mitochondrial respiratory function and enzyme activity, mitochondrial reactive oxygen species (ROS) production rates, and mitochondrial ultrastructure were measured or observed. Compared to the ischemia-reperfusion (I/R) group, HIF-1α expression in the SPostC group was significantly up-regulated. Additionally, cardiac function indicators, mitochondrial state 3 respiratory rate, respiratory control ratio (RCR), cytochrome C oxidase (C c O), NADH oxidase (NADHO), and succinate oxidase (SUCO) activities, mitochondrial ROS production rate, and mitochondrial ultrastructure were significantly better than those in the I/R group. However, these advantages were completely reversed by the HIF-1α specific inhibitor 2ME2 ( P <0.05). The myocardial protective function of SPostC might be associated with the improvement of mitochondrial respiratory function after up-regulation of HIF-1α expression.

  17. Protective effect of edaravone for tourniquet-induced ischemia-reperfusion injury on skeletal muscle in murine hindlimb

    2013-01-01

    Background Studies have shown that ischemia-reperfusion (I/R) produces free radicals leading to lipid peroxidation and damage to skeletal muscle. The purposes of this study were 1) to assess the histological findings of gastrocnemius muscle (GC) and tibialis anterior muscle (TA) in I/R injury model mice, 2) to histologically analyze whether a single pretreatment of edaravone inhibits I/R injury to skeletal muscle in murine models and 3) to evaluate the effect of oxidative stress on these muscles. Methods C57BL6 mice were divided in two groups, with one group receiving 3 mg/kg intraperitoneal injections of edaravone (I/R + Ed group) and the other group receiving an identical amount of saline (I/R group) 30 minutes before ischemia. Edaravone (3-methy-1-pheny1-2-pyrazolin-5-one) is a potent and novel synthetic scavenger of free radicals. This drug inhibits both nonenzymatic lipid peroxidation and the lipoxygenase pathway, in addition to having potent antioxidant effects against ischemia reperfusion. The duration of the ischemia was 1.5 hours, with reperfusion at either 24 or 72 hours (3 days). Specimens of gastrocnemius (GC) and anterior tibialis (TA) were removed for histological evaluation and biochemical analysis. Results This model of I/R injury was highly reproducible in histologic muscle damage. In the histologic damage score, the mean muscle fibers and inflammatory cell infiltration in the I/R + Ed group were significantly less than the corresponding values of observed in the I/R group. Thus, pretreatment with edaravone was observed to have a protective effect on muscle damage after a period of I/R in mice. In addition, the mean muscle injury score in the I/R + Ed group was also significantly less than the I/R group. In the I/R + Ed group, the mean malondialdehyde (MDA) level was lower than in the I/R group and western-blotting revealed that edaravone pretreatment decreased the level of inducible nitric oxide synthase (iNOS) expression. Conclusions Edaravone

  18. Evaluation by contrast-enhanced MR imaging of the lateral border zone in reperfused myocardial infarction in a cat model

    Jeong, Ae Kyung; Choi, Sang Il; Kim, Dong Hun; Park, Sung Bin; Lee, Seoung Soo; Choi, Seong Hoon; Lim, Tae Hwan

    2000-01-01

    To identify and evaluate the lateral border zone by comparing the size and distribution of the abnormal signal area demonstrated by MR imaging with the infarct area revealed by pathological examination in a reperfused myocardial infarction cat model. In eight cats, the left anterior descending coronary artery was occluded for 90 minutes, and this was followed by 90 minutes of reperfusion. ECG-triggered breath-hold turbo spin-echo T2-weighted MR images were initially obtained along the short axis of the heart before the administration of contrast media. After the injection of Gadomer-17 and Gadophrin-2, contrastenhanced T1-weighted MR images were obtained for three hours. The size of the abnormal signal area seen on each image was compared with that of the infarct area after TTC staining. To assess ultrastructural changes in the myocardium at the infarct area, lateral border zone and normal myocardium, electron microscopic examination was performed. The high signal area seen on T2-weighted images and the enhanced area seen on Gadomer-17-enhanced T1WI were larger than the enhanced area on Gadophrin-2-enhanced T1WI and the infarct area revealed by TTC staining; the difference was expressed as a percentage of the size of the total left ventricle mass (T2= 39.2 %; Gadomer-17 =37.25 % vs Gadophrin-2 = 29.6 %; TTC staining = 28.2 %; p < 0.05). The ultrastructural changes seen at the lateral border zone were compatible with reversible myocardial damage. In a reperfused myocardial infarction cat model, the presence and size of the lateral border zone can be determined by means of Gadomer-17- and Gadophrin-2-enhanced MR imaging

  19. Mechanisms of angiogenesis in a Curculigoside A-treated rat model of cerebral ischemia and reperfusion injury

    Zhu, Haibo; He, Jie; Ye, Liang; Lin, Fei; Hou, Jian; Zhong, Yan; Jiang, Wanglin

    2015-01-01

    Curculigoside A has shown protective effects against rat cortical neuron damage in vivo. However, the molecular mechanisms through which Curculigoside A affords this protection are unclear. In the present study, we sought to elucidate the mechanisms of angiogenesis in rat aortic endothelial cells (RAEC), rat aortic smooth muscle cells (RASMC) as well as a rat model of cerebral ischemia and reperfusion injury following treatment with Curculigoside A. We examined the role of Curculigoside A on RAEC and RASMC proliferation, migration, and tube formation in vitro and in a cerebral ischemia and reperfusion injury rat model. We used the recombinant Dickkopf (DKK)-1 protein, a Wnt/β-catenin inhibitor, and the recombinant WIF-1 protein, a Wnt5a antagonist to determine mechanisms. In addition, we measured leakage of the blood–brain barrier (BBB) and tested for angiogenesis associated proteins. Our data suggest that Curculigoside A induces angiogenesis in vitro by increasing proliferation, migration and tube formation in RAEC and RASMC. The increase in Curculigoside A-induced proliferation and tube formation was counteracted by DKK-1 and WIF-1. Curculigoside A increased expression of VEGF, p-VEGFR, p-CREB, Egr-3, VCAM-1, Ang1 and Tie2 while prohibiting BBB leakage in cerebral ischemia and reperfusion injured rats. However, Cyclosporine A, a CREB inhibitor, reduced the expression of p-CREB, Egr-3, VCAM-1, Ang1 and Tie2. These data suggest that Curculigoside A induces cell proliferation and angiogenesis through the Wnt5a/β-catenin and VEGF/CREB/Egr-3/VCAM-1 signaling axis and promotes maturation and stability of new blood vessels via increasing Ang1 and Tie-2 expression. - Highlights: • Curculigoside A induces cell proliferation through Wnt5a/β-catenin pathway. • Curculigoside A induces angiogenesis via VEGF/CREB/Egr-3/VCAM-1 signaling axis. • Curculigoside A promotes blood vessel maturation via Ang1/Tie2 pathway.

  20. [Gene transfer-induced human heme oxygenase-1 over-expression protects kidney from ischemia-reperfusion injury in rats].

    Lü, Jin-xing; Yan, Chun-yin; Pu, Jin-xian; Hou, Jian-quan; Yuan, He-xing; Ping, Ji-gen

    2010-12-14

    To study the protection of gene transfer-induced human heme oxygenase-1 over-expression against renal ischemia reperfusion injury in rats. The model of kidney ischemia-reperfusion injury was established with Sprague-Dawley rats. In the therapy group (n=18), the left kidney was perfused and preserved with Ad-hHO-1 at 2.5×10(9) pfu/1.0 ml after flushed with 0-4°C HC-A organ storage solution via donor renal aorta. The rats in control groups were perfused with 0.9% saline solution (n=12) or the vector carrying no interest gene Ad-EGFP 2.5×10(9) pfu/1.0 ml (n=18) instead of Ad-hHO-1. BUN and Cr in serum were measured by slide chemical methods. The kidney samples of rats were harvested for assay of histology, immunohistochemistry and quantification of HO enzymatic activity. Apoptosis cells in the kidney were measured by TUNEL. Ad-hHO-1 via donor renal aorta could transfect renal cells of rats effectively, enzymatic activity of HO in treated group [(1.62±0.07) nmol×mg(-1)×min(-1)] is higher than in control groups treated with saline solution team [(1.27±0.07) nmol×mg(-1)×min(-1)] and vector EGFP team [(1.22±0.06) nmol×mg(-1)×min(-1)] (PhHO-1 expressed hHO-1 in kidneys at a high level. Corresponding to this, the level of BUN and Cr, as well as the number of apoptosis cells, were decreased, and the damage in histology by HE staining was ameliorated. Over-expression of human HO-1 can protect the kidney from ischemia/reperfusion injury in rats.

  1. Mechanisms of angiogenesis in a Curculigoside A-treated rat model of cerebral ischemia and reperfusion injury

    Zhu, Haibo [School of Public Health and Management, Binzhou Medical University, Yantai (China); Institute of Toxicology, Binzhou Medical University, Yantai (China); He, Jie [State Key Laboratory of Long-acting Targeting Drug Delivery Technologies (Luye Pharma Group Ltd.), Yantai 264003 (China); Ye, Liang [School of Public Health and Management, Binzhou Medical University, Yantai (China); Institute of Toxicology, Binzhou Medical University, Yantai (China); Lin, Fei; Hou, Jian; Zhong, Yan [State Key Laboratory of Long-acting Targeting Drug Delivery Technologies (Luye Pharma Group Ltd.), Yantai 264003 (China); Jiang, Wanglin, E-mail: jwl518@163.com [School of Pharmaceutical Sciences, Institute of Materia Medica, Binzhou Medical University, Yantai (China)

    2015-11-01

    Curculigoside A has shown protective effects against rat cortical neuron damage in vivo. However, the molecular mechanisms through which Curculigoside A affords this protection are unclear. In the present study, we sought to elucidate the mechanisms of angiogenesis in rat aortic endothelial cells (RAEC), rat aortic smooth muscle cells (RASMC) as well as a rat model of cerebral ischemia and reperfusion injury following treatment with Curculigoside A. We examined the role of Curculigoside A on RAEC and RASMC proliferation, migration, and tube formation in vitro and in a cerebral ischemia and reperfusion injury rat model. We used the recombinant Dickkopf (DKK)-1 protein, a Wnt/β-catenin inhibitor, and the recombinant WIF-1 protein, a Wnt5a antagonist to determine mechanisms. In addition, we measured leakage of the blood–brain barrier (BBB) and tested for angiogenesis associated proteins. Our data suggest that Curculigoside A induces angiogenesis in vitro by increasing proliferation, migration and tube formation in RAEC and RASMC. The increase in Curculigoside A-induced proliferation and tube formation was counteracted by DKK-1 and WIF-1. Curculigoside A increased expression of VEGF, p-VEGFR, p-CREB, Egr-3, VCAM-1, Ang1 and Tie2 while prohibiting BBB leakage in cerebral ischemia and reperfusion injured rats. However, Cyclosporine A, a CREB inhibitor, reduced the expression of p-CREB, Egr-3, VCAM-1, Ang1 and Tie2. These data suggest that Curculigoside A induces cell proliferation and angiogenesis through the Wnt5a/β-catenin and VEGF/CREB/Egr-3/VCAM-1 signaling axis and promotes maturation and stability of new blood vessels via increasing Ang1 and Tie-2 expression. - Highlights: • Curculigoside A induces cell proliferation through Wnt5a/β-catenin pathway. • Curculigoside A induces angiogenesis via VEGF/CREB/Egr-3/VCAM-1 signaling axis. • Curculigoside A promotes blood vessel maturation via Ang1/Tie2 pathway.

  2. Homocysteine Aggravates Cortical Neural Cell Injury through Neuronal Autophagy Overactivation following Rat Cerebral Ischemia-Reperfusion

    Yaqian Zhao

    2016-07-01

    Full Text Available Elevated homocysteine (Hcy levels have been reported to be involved in neurotoxicity after ischemic stroke. However, the underlying mechanisms remain incompletely understood to date. In the current study, we hypothesized that neuronal autophagy activation may be involved in the toxic effect of Hcy on cortical neurons following cerebral ischemia. Brain cell injury was determined by hematoxylin-eosin (HE staining and TdT-mediated dUTP Nick-End Labeling (TUNEL staining. The level and localization of autophagy were detected by transmission electron microscopy, western blot and immunofluorescence double labeling. The oxidative DNA damage was revealed by immunofluorescence of 8-Hydroxy-2′-deoxyguanosine (8-OHdG. Hcy treatment aggravated neuronal cell death, significantly increased the formation of autophagosomes and the expression of LC3B and Beclin-1 in the brain cortex after middle cerebral artery occlusion-reperfusion (MCAO. Immunofluorescence analysis of LC3B and Beclin-1 distribution indicated that their expression occurred mainly in neurons (NeuN-positive and hardly in astrocytes (GFAP-positive. 8-OHdG expression was also increased in the ischemic cortex of Hcy-treated animals. Conversely, LC3B and Beclin-1 overexpression and autophagosome accumulation caused by Hcy were partially blocked by the autophagy inhibitor 3-methyladenine (3-MA. Hcy administration enhanced neuronal autophagy, which contributes to cell death following cerebral ischemia. The oxidative damage-mediated autophagy may be a molecular mechanism underlying neuronal cell toxicity of elevated Hcy level.

  3. Nicotine protects kidney from renal ischemia/reperfusion injury through the cholinergic anti-inflammatory pathway.

    Claude Sadis

    Full Text Available Kidney ischemia/reperfusion injury (I/R is characterized by renal dysfunction and tubular damages resulting from an early activation of innate immunity. Recently, nicotine administration has been shown to be a powerful inhibitor of a variety of innate immune responses, including LPS-induced toxaemia. This cholinergic anti-inflammatory pathway acts via the alpha7 nicotinic acetylcholine receptor (alpha7nAChR. Herein, we tested the potential protective effect of nicotine administration in a mouse model of renal I/R injury induced by bilateral clamping of kidney arteries. Renal function, tubular damages and inflammatory response were compared between control animals and mice receiving nicotine at the time of ischemia. Nicotine pretreatment protected mice from renal dysfunction in a dose-dependent manner and through the alpha7nAChR, as attested by the absence of protection in alpha7nAChR-deficient mice. Additionally, nicotine significantly reduced tubular damages, prevented neutrophil infiltration and decreased productions of the CXC-chemokine KC, TNF-alpha and the proinflammatory high-mobility group box 1 protein. Reduced tubular damage in nicotine pre-treated mice was associated with a decrease in tubular cell apoptosis and proliferative response as attested by the reduction of caspase-3 and Ki67 positive cells, respectively. All together, these data highlight that nicotine exerts a protective anti-inflammatory effect during kidney I/R through the cholinergic alpha7nAChR pathway. In addition, this could provide an opportunity to overcome the effect of surgical cholinergic denervation during kidney transplantation.

  4. Inhalation of water electrolysis-derived hydrogen ameliorates cerebral ischemia-reperfusion injury in rats - A possible new hydrogen resource for clinical use.

    Cui, Jin; Chen, Xiao; Zhai, Xiao; Shi, Dongchen; Zhang, Rongjia; Zhi, Xin; Li, Xiaoqun; Gu, Zhengrong; Cao, Liehu; Weng, Weizong; Zhang, Jun; Wang, Liping; Sun, Xuejun; Ji, Fang; Hou, Jiong; Su, Jiacan

    2016-10-29

    Hydrogen is a kind of noble gas with the character to selectively neutralize reactive oxygen species. Former researches proved that low-concentration of hydrogen can be used to ameliorating cerebral ischemia/reperfusion injury. Hydrogen electrolyzed from water has a hydrogen concentration of 66.7%, which is much higher than that used in previous studies. And water electrolysis is a potential new hydrogen resource for regular clinical use. This study was designed and carried out for the determination of safety and neuroprotective effects of water electrolysis-derived hydrogen. Sprague-Dawley rats were used as experimental animals, and middle cerebral artery occlusion was used to make cerebral ischemia/reperfusion model. Pathologically, tissues from rats in hydrogen inhalation group showed no significant difference compared with the control group in HE staining pictures. The blood biochemical findings matched the HE staining result. TTC, Nissl, and TUNEL staining showed the significant improvement of infarction volume, neuron morphology, and neuron apoptosis in rat with hydrogen treatment. Biochemically, hydrogen inhalation decreased brain caspase-3, 3-nitrotyrosine and 8-hydroxy-2-deoxyguanosine-positive cells and inflammation factors concentration. Water electrolysis-derived hydrogen inhalation had neuroprotective effects on cerebral ischemia/reperfusion injury in rats with the effect of suppressing oxidative stress and inflammation, and it is a possible new hydrogen resource to electrolyze water at the bedside clinically. Copyright © 2016. Published by Elsevier Ltd.

  5. Spontaneous Reperfusion after In Situ Thromboembolic Stroke in Mice

    Cho, Tae-Hee; Bolbos, Radu; Langlois, Jean-Baptiste; Hermitte, Laure; Wiart, Marlène; Berthezène, Yves; Nighoghossian, Norbert

    2012-01-01

    Injection of thrombin into the middle cerebral artery (MCA) of mice has been proposed as a new model of thromboembolic stroke. The present study used sequential multiparametric Magnetic Resonance Imaging (MRI), including Magnetic Resonance Angiography (MRA), Diffusion-Weighted Imaging (DWI) and Perfusion-Weighted Imaging (PWI), to document MCA occlusion, PWI-DWI mismatch, and lesion development. In the first experiment, complete MCA occlusion and reproducible hypoperfusion were obtained in 85% of animals during the first hour after stroke onset. In the second experiment, 80% of animals showed partial to complete reperfusion during a three-hour follow-up. Spontaneous reperfusion thus contributed to the variability in ischemic volume in this model. The study confirmed the value of the model for evaluating new thrombolytic treatments, but calls for extended MRI follow-up at the acute stage in therapeutic studies. PMID:23166825

  6. [Ishemic-reperfusion syndrome prophylaxis in general hypothermia in experiment].

    Zubkov, V I; Khytryĭ, H P; Luk'ianchuk, V D; Shalamaĭ, A S

    2009-05-01

    The influence of general supercooling on rats were studied. The action of corvitin and pentoxiphillin on the prooxidant-antioxidant homeostasis for conditions of general supercooling were analysed. On the based of investigations results analysis of lipids peroxide oxidation indexes and antioxidant protection system in animals it were established, that corvitin in difference of pentoxiphillin give more significant protectory effect in conditions of ishemic-reperfusion syndrome.

  7. Discharge Policy and Reperfusion Therapy in Acute Myocardial Infarction

    Vlugt, Maureen

    2007-01-01

    textabstractTreatment of patients with acute myocardial infarction (MI) has improved over time and the duration of hospital stay has considerably decreased. Early hospital discharge after MI has been promoted for over 25 years. However, the meaning of “early” evolved over time. In the early eighties, before the widespread introduction of reperfusion therapy, patients were hospitalised for approximately 3 weeks and early discharge implemented a reduction to 7 days. Nowadays, the average hospit...

  8. Characterization of Microparticles after Hepatic Ischemia-Reperfusion Injury

    Freeman, Christopher M.; Quillin, Ralph C.; Wilson, Gregory C.; Nojima, Hiroyuki; Johnson, Bobby L.; Sutton, Jeffrey M.; Schuster, Rebecca M.; Blanchard, John; Edwards, Michael J.; Caldwell, Charles C.; Lentsch, Alex B.

    2014-01-01

    Background Hepatic ischemia-reperfusion (I/R) is a well-studied model of liver injury and has demonstrated a biphasic injury followed by recovery and regeneration. Microparticles (MPs) are a developing field of study and these small membrane bound vesicles have been shown to have effector function in other physiologic and pathologic states. This study was designed to quantify the levels of MPs from various cell origins–platelets, neutrophils, and endolethial cells–following hepatic ischemia-reperfusion injury. Methods A murine model was used with mice undergoing 90 minutes of partial hepatic ischemia followed by various times of reperfusion. Following reperfusion, plasma samples were taken and MPs of various cell origins were labeled and levels were measured using flow cytometry. Additionally, cell specific MPs were further assessed by Annexin V, which stains for the presence of phosphatidylserine, a cell surface marker linked to apoptosis. Statistical analysis was performed using one-way analysis of variance with subsequent Student-Newman-Keuls test with data presented as the mean and standard error of the mean. Results MPs from varying sources show an increase in circulating levels following hepatic I/R injury. However, the timing of the appearance of different MP subtypes differs for each cell type. Platelet and neutrophil-derived MP levels demonstrated an acute elevation following injury whereas endothelial-derived MP levels demonstrated a delayed elevation. Conclusion This is the first study to characterize circulating levels of cell-specific MPs after hepatic I/R injury and suggests that MPs derived from platelets and neutrophils serve as markers of inflammatory injury and may be active participants in this process. In contrast, MPs derived from endothelial cells increase after the injury response during the reparative phase and may be important in angiogenesis that occurs in the regenerating liver. PMID:24879335

  9. Metabolomic profiling to characterize acute intestinal ischemia/reperfusion injury.

    Rachel G Khadaroo

    Full Text Available Sepsis and septic shock are the leading causes of death in critically ill patients. Acute intestinal ischemia/reperfusion (AII/R is an adaptive response to shock. The high mortality rate from AII/R is due to the severity of the disease and, more importantly, the failure of timely diagnosis. The objective of this investigation is to use nuclear magnetic resonance (NMR analysis to characterize urine metabolomic profile of AII/R injury in a mouse model. Animals were exposed to sham, early (30 min or late (60 min acute intestinal ischemia by complete occlusion of the superior mesenteric artery, followed by 2 hrs of reperfusion. Urine was collected and analyzed by NMR spectroscopy. Urinary metabolite concentrations demonstrated that different profiles could be delineated based on the duration of the intestinal ischemia. Metabolites such as allantoin, creatinine, proline, and methylamine could be predictive of AII/R injury. Lactate, currently used for clinical diagnosis, was found not to significantly contribute to the classification model for either early or late ischemia. This study demonstrates that patterns of changes in urinary metabolites are effective at distinguishing AII/R progression in an animal model. This is a proof-of-concept study to further support examination of metabolites in the clinical diagnosis of intestinal ischemia reperfusion injury in patients. The discovery of a fingerprint metabolite profile of AII/R will be a major advancement in the diagnosis, treatment, and prevention of systemic injury in critically ill patients.

  10. Real-Time Fluorescence Measurements of ROS and [Ca2+] in Ischemic / Reperfused Rat Hearts: Detectable Increases Occur only after Mitochondrial Pore Opening and Are Attenuated by Ischemic Preconditioning.

    Tatyana Andrienko

    Full Text Available Mitochondrial permeability transition pore (mPTP opening is critical for ischemia / reperfusion (I/R injury and is associated with increased [Ca2+] and reactive oxygen species (ROS. Here we employ surface fluorescence to establish the temporal sequence of these events in beating perfused hearts subject to global I/R. A bespoke fluorimeter was used to synchronously monitor surface fluorescence and reflectance of Langendorff-perfused rat hearts at multiple wavelengths, with simultaneous measurements of hemodynamic function. Potential interference by motion artefacts and internal filtering was assessed and minimised. Re-oxidation of NAD(PH and flavoproteins on reperfusion (detected using autofluorescence was rapid (t0.5 < 15 s and significantly slower following ischemic preconditioning (IP. This argues against superoxide production from reduced Complex 1 being a critical mediator of initial mPTP opening during early reperfusion. Furthermore, MitoPY1 (a mitochondria-targeted H2O2-sensitive fluorescent probe and aconitase activity measurements failed to detect matrix ROS increases during early reperfusion. However, two different fluorescent cytosolic ROS probes did detect ROS increases after 2-3 min of reperfusion, which was shown to be after initiation of mPTP opening. Cyclosporin A (CsA and IP attenuated these responses and reduced infarct size. [Ca2+]i (monitored with Indo-1 increased progressively during ischemia, but dropped rapidly within 90 s of reperfusion when total mitochondrial [Ca2+] was shown to be increased. These early changes in [Ca2+] were not attenuated by IP, but substantial [Ca2+] increases were observed after 2-3 min reperfusion and these were prevented by both IP and CsA. Our data suggest that the major increases in ROS and [Ca2+] detected later in reperfusion are secondary to mPTP opening. If earlier IP-sensitive changes occur that might trigger initial mPTP opening they are below our limit of detection. Rather, we suggest that

  11. Effect of picroside II on hind limb ischemia reperfusion injury in rats

    Kılıç Y

    2017-06-01

    Full Text Available Yiğit Kılıç,1 Abdullah Özer,1 Tolga Tatar,1 Mustafa Hakan Zor,1 Mehmet Kirişçi,2 Hakan Kartal,3 Ali Doğan Dursun,4 Deniz Billur,5 Mustafa Arslan,6 Ayşegül Küçük7 1Department of Cardiovascular Surgery, Gazi University Medical Faculty, Ankara, 2Department of Cardiovascular Surgery, Kahramanmaras Sutcu Imam Medical Faculty, Kahramanmaras, 3Department of Cardiovascular Surgery, Ardahan State Hospital, Ardahan, 4Department of Physiology, Ankara University Medical Faculty, 5Department of Histology and Embryology, Ankara University Medical Faculty, 6Department of Anaesthesiology and Reanimation, Gazi University Medical Faculty, Ankara, 7Department of Physiology, Dumlupinar University Medical Faculty, Kütahya, Turkey Introduction: Many structural and functional damages are observed in cells and tissues after reperfusion of previously viable ischemic tissues. Acute ischemia reperfusion (I/R injury of lower extremities occurs especially when a temporary cross-clamp is applied to the abdominal aorta during aortic surgery. Research regarding the treatment of I/R injury has been increasing day-by-day. In this study, we aimed to investigate the effect of picroside II on skeletal muscle of rats experiencing simulated I/R.Materials and methods: Twenty-four male Wistar albino rats weighing between 210 and 300 g were used in this study. Rats were randomly divided into 4 groups of 6 rats each (control, I/R, control + picroside II, and I/R + picroside II. The infrarenal section of the abdominal aorta was occluded with an atraumatic microvascular clamp in I/R group. The clamp was removed after 120 minutes and reperfusion was provided for a further 120 minutes. Picroside II (10 mg kg–1 was administered intraperitoneally to the animals in control + picroside II and I/R + picroside II groups. At the end of the study, skeletal muscle tissue was obtained for the determination of total oxidant status (TOS and total antioxidant status (TAS levels

  12. Protective effects of persian honey, Apis Mellifera Meda Skorikov on side effects of chemotherapy and ischemia/reperfusion induced testicular injury.

    Gholami, Mohammadreza; Abbaszadeh, Abolfazl; Baharvand, Parastoo; Hasanvand, Afshin; Hasanvand, Amin; Gharravi, Anneh Mohammad

    2018-05-23

    Introduction The aim of the present study was to survey the protective effect of pretreatment with Persian honey on amelioration of side effects of chemotherapy and ischemia/reperfusion induced testicular injury. Materials and methods Forty adult's male wistar rats were divided into four groups of ischemia-reperfusion (IR), honey + ischemia-reperfusion (HIR), Busulfan (B) and Busulfan intraperitoneally+ honey (BH). The seminiferous tubules were rated for their modified spermatogenesis index (SI) by Johnsons score. Detection of single- and double-stranded DNA breaks at the early stages of apoptosis was performed using the in-situ cell death detection kit. Total serum concentration of Follicle-stimulating hormone (FSH) , Luteinizing hormone (LH) and testosterone was measured using ELISA. All data were expressed as mean ± SD and significance was set at p≤0.05. Results Honey improved SI in the HIR and BH groups and serum levels of FSH and LH in the BH and HIR groups (phoney protect testis against chemotherapy and testicular IR injury, increase FSH and LH and testosterone and decrease the cellular damage and apoptosis. Honey can decrease the side effects of chemotherapy on reproductive system and prevent sterility.

  13. The evaluation of usefulness of quantitative analysis method with {sup 99m}Tc-tetrofosmin on effective dicision of reperfusion therapy to acute myocardial infarction

    Takagi, Hitoshi; Sone, Takahito [Ogaki Municipal Hospital, Gifu (Japan)

    1998-01-01

    SPECT on acute and chronic period of {sup 99m}Tc-tetrofosmin on 46 patients with acute myocardial infarction were analyzed to evaluate about usefulness of quantitative analysis method used by unfolding image that was gotten by Bull`s eye analysis on reperfusion therapy in acute myocardial infarction, and we could get undermentioned results. 60% black out area in resional of interested was best on the obstacle myocardium using analysis of unfolding image. Significantly betterment from acute to chronic phase on the obstacle area of myocardium and the mean uptake ratio of the obstacle area was confirmed by this method. The relation between myocardial salvage and factors of myocardial damage, for example reperfusion time TIMI grade, rentrop grade and reperfusion phenomenon could be analyzed by this method. This method was suspected to underestimate the areas of obstacle myocardium on the cases of defect of apex. Error of analysis was suspected on the case of accumulation of TF to other than myocardium. The problems were minimised by some techniques mention in this paper. (author)

  14. [Effects of combined use of total alkaloids of Uncaria rhynchophylla and Coryadlis ambailis migo on cerebral ischemia-reperfusion injury in rats].

    Hu, Xue-yong; Sun, An-sheng; Sui, Yu-xia

    2007-11-01

    To study the effects of combined use of total alkaloids (TA) of Uncaria rhynchophylla (UR) and Coryadlis ambailis migo (CAM) on cerebral ischemia/reperfusion injury in rats. Rat model of middle cerebral artery ischemia/reperfusion was established, the changes of neurological state was scored before and after treatment with the two kinds of TA, single or combined, and the changes of cerebral infarcted volume, cerebral water content, activities of NOS and SOD and content of MDA in rats' brain were estimated as well. After being treated with the combination of both TA, the average neurological score, cerebral infracted volume, cerebral water content, activity of NOS and content of MDA in the model rats significantly decreased, and the activity of SOD was significantly increased (all P < 0.05). The effect of combined use of the two TA was higher than that of use TA of UR or CAM alone (P <0.05). Moreover, the central nervous system inhibitory effect induced by combined TA was significantly weaker than that of UR. Combined use of TA of UR and CAM may facilitate the protection against cerebral ischemia/reperfusion damage, the action mechanism might be relevant to reducing the lipid peroxidation injury of brain cells through inhibiting the NOS activity and increasing the SOD activity.

  15. The role of indoleamine 2,3 dioxygenase in beneficial effects of stem cells in hind limb ischemia reperfusion injury.

    Mohamad Masoumy

    Full Text Available Ischemia-Reperfusion (IR injury of limb remains a significant clinical problem causing secondary complications and restricting clinical recovery, despite rapid restoration of blood flow and successful surgery. In an attempt to further improve post ischemic tissue repair, we investigated the effect of a local administration of bone marrow derived stem cells (BMDSCs in the presence or absence of immune-regulatory enzyme, IDO, in a murine model. A whole limb warm ischemia-reperfusion model was developed using IDO sufficient (WT and deficient (KO mice with C57/BL6 background. Twenty-four hours after injury, 5 × 105 cells (5×105 cells/200 µL of PBS solution BMDSCs (Sca1 + cells were injected intramuscularly while the control group received just the vehicle buffer (PBS. Forty-eight to seventy-two hours after limb BMDSC injection, recovery status including the ratio of intrinsic paw function between affected and normal paws, general mobility, and inflammatory responses were measured using video micrometery, flow cytometry, and immunohistochemistry techniques. Additionally, MRI/MRA studies were performed to further study the inflammatory response between groups and to confirm reconstitution of blood flow after ischemia. For the first time, our data, showed that IDO may potentially represent a partial role in triggering the beneficial effects of BMDSCs in faster recovery and protection against structural changes and cellular damage in a hind limb IR injury setting (P = 0.00058.

  16. Extract of grapefruit-seed reduces acute pancreatitis induced by ischemia/reperfusion in rats: possible implication of tissue antioxidants.

    Dembinski, A; Warzecha, Z; Konturek, S J; Ceranowicz, P; Dembinski, M; Pawlik, W W; Kusnierz-Cabala, B; Naskalski, J W

    2004-12-01

    Grapefruit seed extract (GSE) has been shown to exert antibacterial, antifungal and antioxidant activity possibly due to the presence of naringenin, the flavonoid with cytoprotective action on the gastric mucosa. No study so far has been undertaken to determine whether this GSE is also capable of preventing acute pancreatic damage induced by ischemia/reperfusion (I/R), which is known to result from reduction of anti-oxidative capability of pancreatic tissue, and whether its possible preventive effect involves an antioxidative action of this biocomponent. In this study carried out on rats with acute hemorrhagic pancreatitis induced by 30 min partial pancreatic ischemia followed by 6 h of reperfusion, the GSE or vehicle (vegetable glycerin) was applied intragastrically in gradually increasing amounts (50-500 microl) 30 min before I/R. Pretreatment with GSE decreased the extent of pancreatitis with maximal protective effect of GSE at the dose 250 microl. GSE reduced the pancreatitis-evoked increase in serum lipase and poly-C specific ribonuclease activity, and attenuated the marked fall in pancreatic blood flow and pancreatic DNA synthesis. GSE administered alone increased significantly pancreatic tissue content of lipid peroxidation products, malondialdehyde and 4-hydroxyalkens, and when administered before I/R, GSE reduced the pancreatitis-induced lipid peroxidation. We conclude that GSE exerts protective activity against I/R-induced pancreatitis probably due to the activation of antioxidative mechanisms in the pancreas and the improvement of pancreatic blood flow.

  17. Cardioprotective Effect of Aloe vera Biomacromolecules Conjugated with Selenium Trace Element on Myocardial Ischemia-Reperfusion Injury in Rats.

    Yang, Yang; Yang, Ming; Ai, Fen; Huang, Congxin

    2017-06-01

    The present study was undertaken to evaluate the cardioprotection potential and underlying molecular mechanism afforded by a selenium (Se) polysaccharide (Se-AVP) from Aloe vera in the ischemia-reperfusion (I/R) model of rats in vivo. Myocardial I/R injury was induced by occluding the left anterior descending coronary artery (LAD) for 30 min followed by 2-h continuous reperfusion. Pretreatment with Se-AVP (100, 200, and 400 mg/kg) attenuated myocardial damage, as evidenced by reduction of the infarct sizes, increase in serum and myocardial endogenous antioxidants (superoxide dismutase (SOD), glutathione peroxidase (GSH), and catalase (CAT)), and decrease in the malondialdehyde (MDA) level in the rats suffering I/R injury. This cardioprotective activity afforded by Se-AVP is further supported by the decreased levels of cardiac marker enzymes creatine kinase (CK) and lactate dehydrogenase (LDH), as well as the rise of myocardial Na + -K + -ATPase and Ca 2+ -Mg 2+ -ATPase activities in I/R rats. Additionally, cardiomyocytic apoptosis was measured by terminal-deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) staining and the result showed that the percent of TUNEL-positive cells in myocardium of Se-AVP-treated groups was lower than I/R rats. In conclusion, we clearly demonstrated that Se-AVP had a protective effect against myocardial I/R injury in rats by augmenting endogenous antioxidants and protecting rat hearts from oxidative stress-induced myocardial apoptosis.

  18. Novel curcumin analogue 14p protects against myocardial ischemia reperfusion injury through Nrf2-activating anti-oxidative activity

    Li, Weixin [Department of Cardiology, The 5th Affiliated Hospital of Wenzhou Medical University, Lishui, Zhejiang (China); Chemical Biology Research Center, School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou, Zhejiang (China); Wu, Mingchai [Department of Pharmacy, The Third Affiliated Hospital of Wenzhou Medical University, Wenzou, Zhejiang (China); Tang, Longguang; Pan, Yong; Liu, Zhiguo [Chemical Biology Research Center, School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou, Zhejiang (China); Zeng, Chunlai [Department of Cardiology, The 5th Affiliated Hospital of Wenzhou Medical University, Lishui, Zhejiang (China); Wang, Jingying [Chemical Biology Research Center, School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou, Zhejiang (China); Wei, Tiemin, E-mail: lswtm@sina.com [Department of Cardiology, The 5th Affiliated Hospital of Wenzhou Medical University, Lishui, Zhejiang (China); Liang, Guang, E-mail: wzmcliangguang@163.com [Chemical Biology Research Center, School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou, Zhejiang (China)

    2015-01-15

    Background: Alleviating the oxidant stress associated with myocardial ischemia reperfusion has been demonstrated as a potential therapeutic approach to limit ischemia reperfusion (I/R)-induced cardiac damage. Curcumin, a natural compound with anti-oxidative activity, exerts beneficial effect against cardiac I/R injury, but poor chemical and metabolic stability. Previously, we have designed and synthesized a series of mono-carbonyl analogues of curcumin (MACs) with high stability. This study aims to find new anti-oxidant MACs and to demonstrate their effects and mechanisms against I/R-induced heart injury. Methods: H9c2 cells challenged with H{sub 2}O{sub 2} or TBHP were used for in vitro bio-screening and mechanistic studies. The MDA, H{sub 2}O{sub 2} and SOD levels in H9C2 cells were determined, and the cell viability was assessed by MTT assay. Myocardial I/R mouse models administrated with or without the compound were used for in vivo studies. Results: The in vitro cell-based screening showed that curcumin analogues 8d and 14p exhibited strong anti-oxidative effects. Pre-treatment of H9c2 cells with 14p activated Nrf2 signaling pathway, attenuated H{sub 2}O{sub 2}-increased MDA and SOD level, followed by the inhibition of TBHP-induced cell death and Bax/Bcl-2–caspase-3 pathway activation. Silencing Nrf2 significantly reversed the protective effects of 14p. In in vivo animal model of myocardial I/R, administration of low dose 14p (10 mg/kg) reduced infarct size and myocardial apoptosis to the same extent as the high dose curcumin (100 mg/kg). Conclusion: These data support the novel curcumin analogue 14p as a promising antioxidant to decrease oxidative stress and limit myocardial ischemia reperfusion injury via activating Nrf2. - Highlights: • Mono-carbonyl analogue of curcumin, 14p, exhibited better chemical stability. • Compound 14p inhibited TBHP-induced apoptosis through activating Nrf2 in vitro. • Compound 14p limited myocardial ischemia/reperfusion

  19. Protective effect and its mechanism of curcumin on ischemia-reperfusion injury of cerebral cortex in rats

    Li LIU

    2013-03-01

    Full Text Available Objective  To investigate the effect of curcumin pretreatment on the expression of uncoupling protein 2 (UCP2 and mitochondrial transcription factor A (MTFA in rats' cerebral cortex against focal ischemia reperfusion injury. Methods  Eighty male SD rats weighed 220g–300g were randomly divided into 4 groups: sham-operated group, ischemia/reperfusion (I/R group, curcumine 50mg/kg+I/R (low dose group, and curcumine 100mg/kg+I/R (high dose group. The common carotid artery, external carotid artery and internal carotid artery on the right side were exposed in the sham-operated group. Animals of the other groups were subjected to a 2-hour period of right middle cerebral artery occlusion, followed by 24 hours of reperfusion, and then they were sacrificed. Curcumin was administered (ip in a dose of 50mg/kg (low dose group or 100mg/kg (high dose group for 5 days, respectively, prior to arterial occlusion. The pathological changes in neurons and their mitochondria in the cerebral cortex supplied by middle cerebral artery were observed with Nissl staining and electron microscope, respectively. The expressions of UCP2 and MTFA in corresponding cotex were assessed by immunohistochemistry and RT-PCR. Results  Compared with sham-operated group, animals in I/R group presented edema of neurons in the corresponding cortex, reduction in the number of Nissl bodies, and swelling of mitochondria with broken, even lysis of cristae. Low dose and high dose of curcumin pretreatment before brain ischemia significantly alleviated the loss of neurons and the damage of mitochondria, accompanied with an increase in the expression of UCP2 and TFAM (P<0.05, and the changes appeared a dose-dependent manner (P<0.05. Conclusions  Curcumin may prevent neurons from focal cerebral ischemia reperfusion injury by up-regulating UCP2 and MTFA. Regulation of mitochondrial biogenesis may probably be a potential target of curcumin as a neuroprotective drug.

  20. The administration of hydrogen sulphide prior to ischemic reperfusion has neuroprotective effects in an acute stroke model.

    Chul-Woong Woo

    Full Text Available Emerging evidence has suggested that hydrogen sulfide (H2S may alleviate the cellular damage associated with cerebral ischemia/reperfusion (I/R injury. In this study, we assessed using 1H-magnetic resonance imaging/magnetic resonance spectroscopy (1H-MRI/MRS and histologic analysis whether H2S administration prior to reperfusion has neuroprotective effects. We also evaluated for differences in the effects of H2S treatment at 2 time points. 1H-MRI/MRS data were obtained at baseline, and at 3, 9, and 24 h after ischemia from 4 groups: sham, control (I/R injury, sodium hydrosulfide (NaHS-30 and NaHS-1 (NaHS delivery at 30 and 1 min before reperfusion, respectively. The total infarct volume and the midline shift at 24 h post-ischemia were lowest in the NaHS-1, followed by the NaHS-30 and control groups. Peri-infarct volume was significantly lower in the NaHS-1 compared to NaHS-30 and control animals. The relative apparent diffusion coefficient (ADC in the peri-infarct region showed that the NaHS-1 group had significantly lower values compared to the NaHS-30 and control animals and that NaHS-1 rats showed significantly higher relative T2 values in the peri-infarct region compared to the controls. The relative ADC value, relative T2 value, levels of N-acetyl-L-aspartate (NAA, and the NAA, glutamate, and taurine combination score (NGT in the ischemic core region at 24 h post-ischemia did not differ significantly between the 2 NaHS groups and the control except that the NAA and NGT values were higher in the peri-infarct region of the NaHS-1 animals at 9 h post-ischemia. In the ischemic core and peri-infarct regions, the apoptosis rate was lowest in the NaHS-1 group, followed by the NaHS-30 and control groups. Our results suggest that H2S treatment has neuroprotective effects on the peri-infarct region during the evolution of I/R injury. Furthermore, our findings indicate that the administration of H2S immediately prior to reperfusion produces the

  1. Oxygen safety

    ... sure you have working smoke detectors and a working fire extinguisher in your home. If you move around the house with your oxygen, you may need more than one fire extinguisher in different locations. Smoking can be very dangerous. No one should smoke ...

  2. A novel bioactivity of andrographolide from Andrographis paniculata on cerebral ischemia/reperfusion-induced brain injury through induction of cerebral endothelial cell apoptosis.

    Yen, Ting-Lin; Hsu, Wen-Hsien; Huang, Steven Kuan-Hua; Lu, Wan-Jung; Chang, Chao-Chien; Lien, Li-Ming; Hsiao, George; Sheu, Joen-Rong; Lin, Kuan-Hung

    2013-09-01

    Andrographolide, extracted from the leaves of Andrographis paniculata (Burm. f.) Nees (Acanthaceae), is a labdane diterpene lactone. It is widely reported to possess anti-inflammatory and antitumorigenic activities. Cerebral endothelial cells (CECs) play a crucial role in supporting the integrity and the function of the blood-brain barrier (BBB). However, no data are available concerning the effects of andrographolide in CECs. The aim of this study was to examine the detailed mechanisms of andrographolide on CECs. This study investigated a novel bioactivity of andrographolide on cerebral ischemia/reperfusion-induced brain injury. CECs were treated with andrographolide (20-100 µΜ) for the indicated times (0-24 h). After the reactions, cell survival rate and cytotoxicity were tested by the MTT assay and the lactate dehydrogenase (LDH) test, respectively. Western blotting was used to detect caspase-3 expression. In addition, analysis of cell cycle and apoptosis using PI staining and annexin V-FITC/PI labeling, respectively, was performed by flow cytometry. We also investigated the effect of andrographolide on middle cerebral artery occlusion (MCAO)/reperfusion-induced brain injury in a rat model. In the present study, we found that andrographolide (50-100 µΜ) markedly inhibited CEC growth according to an MTT assay and caused CEC damage according to a LDH test. Our data also revealed that andrographolide (50 µM) induced CEC apoptosis and caspase-3 activation as respectively detected by PI/annexin-V double staining and western blotting. Moreover, andrographolide arrested the CEC cell cycle at the G0/G1 phase by PI staining. In addition, andrographolide (5 mg/kg) caused deterioration of MCAO/reperfusion-induced brain injury in a rat model. These data suggest that andrographolide may disrupt BBB integrity, thereby deteriorating MCAO/reperfusion-induced brain injury, which are, in part, associated with its capacity to arrest cell-cycle and induce CEC

  3. Using multiphoton fluorescence lifetime imaging to characterize liver damage and fluorescein disposition in liver in vivo

    Thorling, Camilla A.; Studier, Hauke; Crawford, Darrell; Roberts, Michael S.

    2016-03-01

    Liver disease is the fifth most common cause of death and unlike many other major causes of mortality, liver disease rates are increasing rather than decreasing. There is no ideal measurement of liver disease and although biopsies are the gold standard, this only allows for a spot examination and cannot follow dynamic processes of the liver. Intravital imaging has the potential to extract detailed information over a larger sampling area continuously. The aim of this project was to investigate whether multiphoton and fluorescence lifetime imaging microscopy could detect early liver damage and to assess whether it could detect changes in metabolism of fluorescein in normal and diseased livers. Four experimental groups were used in this study: 1) control; 2) ischemia reperfusion injury; 3) steatosis and 4) steatosis with ischemia reperfusion injury. Results showed that multiphoton microscopy could visualize morphological changes such as decreased fluorescence of endogenous fluorophores and the presence of lipid droplets, characteristic of steatosis. Fluorescence lifetime imaging microscopy showed increase in NADPH in steatosis with and without ischemia reperfusion injury and could detect changes in metabolism of fluorescein to fluorescein monoglurcuronide, which was impaired in steatosis with ischemia reperfusion injury. These results concluded that the combination of multiphoton microscopy and fluorescence lifetime imaging is a promising method of assessing early stage liver damage and that it can be used to study changes in drug metabolism in the liver as an indication of liver disease and has the potential to replace the traditional static liver biopsy currently used.

  4. Oxygen therapy - infants

    ... breathe increased amounts of oxygen to get normal levels of oxygen in their blood. Oxygen therapy provides babies with the extra oxygen. Information Oxygen is a gas that the cells in your body need to work properly. The ...

  5. Radiation damage

    Heijne, Erik H M; CERN. Geneva

    1998-01-01

    a) Radiation damage in organic materials. This series of lectures will give an overview of radiation effects on materials and components frequently used in accelerator engineering and experiments. Basic degradation phenomena will be presented for organic materials with comprehensive damage threshold doses for commonly used rubbers, thermoplastics, thermosets and composite materials. Some indications will be given for glass, scintillators and optical fibres. b) Radiation effects in semiconductor materials and devices. The major part of the time will be devoted to treat radiation effects in semiconductor sensors and the associated electronics, in particular displacement damage, interface and single event phenomena. Evaluation methods and practical aspects will be shown. Strategies will be developed for the survival of the materials under the expected environmental conditions of the LHC machine and detectors. I will describe profound revolution in our understanding of black holes and their relation to quantum me...

  6. The effect of intermittent fasting and water restriction on myocardial ischemia/reperfusion-induced arrhythmia in rats

    KAYA, Salih Tunç; BOZDOĞAN, Ömer

    2011-01-01

    To investigate the effect of intermittent fasting and water restriction on ischemia/reperfusion-induced arrhythmias. Materials and methods: Six minutes of ischemia followed by 6 min of reperfusion was produced by the ligation and then releasing of the left coronary artery. Intermittent fasting and water restriction were applied during 1 month for 12 h/day. The duration, type, and incidence of arrhythmias during reperfusion and the survival rate at the end of reperfusion were determined and c...

  7. Volume regulated anion channel currents of rat hippocampal neurons and their contribution to oxygen-and-glucose deprivation induced neuronal death.

    Huaqiu Zhang

    2011-02-01

    Full Text Available Volume-regulated anion channels (VRAC are widely expressed chloride channels that are critical for the cell volume regulation. In the mammalian central nervous system, the physiological expression of neuronal VRAC and its role in cerebral ischemia are issues largely unknown. We show that hypoosmotic medium induce an outwardly rectifying chloride conductance in CA1 pyramidal neurons in rat hippocampal slices. The induced chloride conductance was sensitive to some of the VRAC inhibitors, namely, IAA-94 (300 µM and NPPB (100 µM, but not to tamoxifen (10 µM. Using oxygen-and-glucose deprivation (OGD to simulate ischemic conditions in slices, VRAC activation appeared after OGD induced anoxic depolarization (AD that showed a progressive increase in current amplitude over the period of post-OGD reperfusion. The OGD induced VRAC currents were significantly inhibited by inhibitors for glutamate AMPA (30 µM NBQX and NMDA (40 µM AP-5 receptors in the OGD solution, supporting the view that induction of AD requires an excessive Na(+-loading via these receptors that in turn to activate neuronal VRAC. In the presence of NPPB and DCPIB in the post-OGD reperfusion solution, the OGD induced CA1 pyramidal neuron death, as measured by TO-PRO-3-I staining, was significantly reduced, although DCPIB did not appear to be an effective neuronal VRAC blocker. Altogether, we show that rat hippocampal pyramidal neurons express functional VRAC, and ischemic conditions can initial neuronal VRAC activation that may contribute to ischemic neuronal damage.

  8. The short term effects of resveratrol on ischemia-reperfusion injury in rat testis.

    Yuluğ, Esin; Türedi, Sibel; Karagüzel, Ersagun; Kutlu, Omer; Menteşe, Ahmet; Alver, Ahmet

    2014-03-01

    The purpose of this study was to identify changes taking place in the rat testis at the 24th hour of reperfusion following testicular torsion and to evaluate the effects of resveratrol (RSV), a powerful antioxidant, in preventing these changes using novel biochemical parameters and histopathology. Eighteen adult male rats were divided into three groups: Sham-operated (S), torsion/detorsion (T/D), and T/D+RSV groups. In the T/D group, testicular ischemia was achieved by rotating the left testis 720° clockwise for 4h. In the T/D+RSV group, 20mg/kg RSV was administered intraperitoneally 30 min before detorsion. All rats were sacrificed 24h after detorsion. Serum and tissue malondialdehyde (MDA) concentrations, ischemia modified albumin (IMA), total oxidative status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), and histopathological damage score were analyzed. Serum MDA, IMA, TOS, and OSI levels rose significantly in the T/D group. Serum MDA and IMA values were lower in the T/D+RES groups, but not significantly. OSI and TOS values were lower in the T/D+RES group, and the difference was significant. TAS values decreased significantly in the T/D group and rose in the T/D+RSV group, but not significantly. Ipsilateral tissue MDA values were significantly elevated in the T/D group and decreased in the T/D+RSV group, but not significantly. Apoptosis and histopathological damage increased significantly in the T/D group and decreased significantly in the T/D+RSV group. In the contralateral testis, apoptosis increased significantly in the T/D group. It decreased significantly in the T/D+RSV group. Our findings show that RSV had a protective effect against oxidative damage induced with a testicular T/D model, especially at the antiapoptotic and histopathological level. OSI may be a good guide to the clinical status of testicular T/D. © 2014.

  9. Hypoperfusion Induced by Preconditioning Treadmill Training in Hyper-Early Reperfusion After Cerebral Ischemia: A Laser Speckle Imaging Study.

    He, Zhijie; Lu, Hongyang; Yang, Xiaojiao; Zhang, Li; Wu, Yi; Niu, Wenxiu; Ding, Li; Wang, Guili; Tong, Shanbao; Jia, Jie

    2018-01-01

    Exercise preconditioning induces neuroprotective effects during cerebral ischemia and reperfusion, which involves the recovery of cerebral blood flow (CBF). Mechanisms underlying the neuroprotective effects of re-established CBF following ischemia and reperfusion are unclear. The present study investigated CBF in hyper-early stage of reperfusion by laser speckle contrast imaging, a full-field high-resolution optical imaging technique. Rats with or without treadmill training were subjected to middle cerebral artery occlusion followed by reperfusion. CBF in arteries, veins, and capillaries in hyper-early stage of reperfusion (1, 2, and 3 h after reperfusion) and in subacute stage (24 h after reperfusion) were measured. Neurological scoring and 2,3,5-triphenyltetrazolium chloride staining were further applied to determine the neuroprotective effects of exercise preconditioning. In hyper-early stage of reperfusion, CBF in the rats with exercise preconditioning was reduced significantly in arteries and veins, respectively, compared to rats with no exercise preconditioning. Capillary CBF remained stable in the hyper-early stage of reperfusion, though it increased significantly 24 h after reperfusion in the rats with exercise preconditioning. As a neuroprotective strategy, exercise preconditioning reduced the blood perfusion of arteries and veins in the hyper-early stage of reperfusion, which indicated intervention-induced neuroprotective hypoperfusion after reperfusion onset.

  10. Ex-vivo and in vitro protective effects of kolaviron against oxygen-derived radical-induced DNA damage and oxidative stress in human lymphocytes and rat liver cells

    Farombi, E.O.; Moller, P.; Dragsted, L.O.

    2004-01-01

    at concentrations between 30-90 mumol/L and decreased H2O2-induced DNA strand breaks and oxidized bases. Neither alpha-tocopherol nor curcumin decreased H2O2-induced DNA damage in this assay. In lymphocytes incubated with Fe3+ /GSH, Fe3+ was reduced to Fe2+ by GSH initiating a free radical generating reaction which...

  11. Endotoxin tolerance does not limit mild ischemia-reperfusion injury in humans in vivo.

    Draisma, A.; Goeij, M. de; Wouters, C.W.; Riksen, N.P.; Oyen, W.J.G.; Rongen, G.A.P.J.M.; Boerman, O.C.; Deuren, M. van; Hoeven, J.G. van der; Pickkers, P.

    2009-01-01

    Animal studies have shown that previous exposure to lipopolysaccharide (LPS) can limit ischemia-reperfusion injury. We tested whether pretreatment with LPS also protects against ischemia-reperfusion injury in humans in vivo. Fourteen volunteers received bolus injections of incremental dosages of LPS

  12. Effect of 5-aminosalicylic acid on myocardial capillary permeability following ischaemia and reperfusion

    Hansen, P R; Svendsen, Jesper Hastrup; Høst, N B

    1992-01-01

    The aim was to evaluate the effect of 5-aminosalicylic acid on myocardial capillary permeability for small hydrophilic molecules after ischaemia and reperfusion.......The aim was to evaluate the effect of 5-aminosalicylic acid on myocardial capillary permeability for small hydrophilic molecules after ischaemia and reperfusion....

  13. Reperfusion therapy for ST elevation acute myocardial infarction 2010/2011

    Kristensen, Steen D; Laut, Kristina G; Fajadet, Jean

    2014-01-01

    AIMS: Primary percutaneous coronary intervention (PPCI) is the preferred reperfusion therapy in ST-elevation myocardial infarction (STEMI). We conducted this study to evaluate the contemporary status on the use and type of reperfusion therapy in patients admitted with STEMI in the European Society...

  14. Retinal reperfusion in diabetic retinopathy following treatment with anti-VEGF intravitreal injections

    Levin AM

    2017-01-01

    Full Text Available Ariana M Levin, Irene Rusu, Anton Orlin, Mrinali P Gupta, Peter Coombs, Donald J D’Amico, Szilárd Kiss Department of Ophthalmology, Weill Cornell Medical College, New York, NY, USA Purpose: The aim of this study is to report peripheral reperfusion of ischemic areas of the retina on ultra-widefield fluorescein angiography (UWFA following anti-vascular endothelial growth factor (VEGF intravitreal injections in patients treated for diabetic retinopathy. Methods: This study is a retrospective review of 16 eyes of 15 patients with diabetic retinopathy, who received anti-VEGF intravitreal injections and underwent pre- and postinjection UWFA. The main outcome measured was the presence of reperfusion in postinjection UWFA images in areas of the retina that demonstrated nonperfusion in preinjection images. Images were analyzed for reperfusion qualitatively and quantitatively by two graders. Results: Twelve of 16 eyes (75% or 11 of 15 patients (73.3% demonstrated reperfusion following anti-VEGF injection. On UWFA, reperfusion was detected both within the field of 7-standard field (7SF fluorescein angiography and in the periphery outside the 7SF. Four of 16 eyes or 4 of 15 patients did not demonstrate reperfusion, one of which had extensive scarring from prior panretinal photocoagulation. Conclusion: In patients with diabetic retinopathy, treatment with anti-VEGF agents can be associated with reperfusion of areas of nonperfusion, as demonstrated by UWFA. Keywords: anti-VEGF, diabetes, diabetic retinopathy, ischemia, perfusion, reperfusion

  15. Sphingosine-1-Phosphate reduces ischemia/reperfusion injury by phosphorylating the gap junction protein Connexin43

    Morel, Sandrine; Christoffersen, Christina; Axelsen, Lene N

    2016-01-01

    recruitment seems only indirectly affected. Importantly, short-term S1P treatment at the onset of reperfusion was sufficient to reduce ischemia/reperfusion injury in isolated perfused hearts. Mechanistic in vitro and ex vivo studies revealed that 5 min of S1P treatment induced phosphorylation of the gap...

  16. Sustained benefit of temporary limited reperfusion in skeletal muscle following ischemia

    Anderson, R.J.; Cambria, R.; Kerr, J.; Hobson, R.W. II

    1990-01-01

    Limiting the rate of reperfusion blood flow following prolonged ischemia in skeletal muscle has been shown beneficial. However, the persistence of this benefit with reinstitution of normal blood flow remains undefined. We investigated the role of temporary limited reperfusion on ischemia-reperfusion injury in an isolated gracilis muscle model in six anesthetized dogs. Both gracilis muscles were subjected to 6 hr of ischemia followed by 2 hr of reperfusion. Reperfusion blood flow was limited for the first hour in one gracilis muscle to its preischemic rate followed by a second hour of normal reperfusion (LR/NR). The contralateral muscle underwent 2 hr of normal reperfusion (NR/NR). Muscle injury was quantified by technetium-99m pyrophosphate (TcPyp) uptake and by histochemical staining using triphenyltetrazolium chloride (TTC) with planimetry of the infarct size. Capillary permeability was evaluated by muscle weight gain. Results are reported as the mean +/- SEM. These data demonstrate a sustained benefit from temporary limited reperfusion. This methodology should be considered in the surgical management of the acutely ischemic limb

  17. Reduced ischemia-reperfusion injury with isoproterenol in non-heart-beating donor lungs.

    Jones, D R; Hoffmann, S C; Sellars, M; Egan, T M

    1997-05-01

    Transplantation of lungs retrieved from non-heart-beating donors could expand the donor pool. Recent studies suggest that the ischemia-reperfusion injury (IRI) to the lung can be attenuated by increasing intracellular cAMP concentrations. The purpose of this study was to determine the effect of IRI on capillary permeability, as measured by Kfc, in lungs retrieved from non-heart-beating donors and reperfused with or without isoproterenol (iso). Using an in situ isolated perfused lung model, lungs were retrieved from non-heart-beating donor rats ventilated with O2 or not at varying intervals after death. The lungs were reperfused with or without iso (10 microM). Kfc, lung viability, and pulmonary hemodynamics were measured, and tissue levels of adenine nucleotides and cAMP were measured by HPLC. Iso-reperfusion decreased Kfc significantly (P Kfc in non-iso-reperfused (r = 0.65) and iso-perfused (r = 0.84) lungs. cAMP levels increased significantly with iso-reperfusion. cAMP levels correlated with Kfc (r = 0.87) in iso-reperfused lungs. Iso-reperfusion of lungs retrieved from non-heart-beating donor rats results in decreased capillary permeability and increased lung tissue cAMP levels. Pharmacologic augmentation of tissue TAN and cAMP levels may further ameliorate the increased capillary permeability seen in lungs retrieved from non-heart-beating donors.

  18. Reduced cerebral ischemia-reperfusion injury in Toll-like receptor 4 deficient mice

    Cao Canxiang; Yang Qingwu; Lv Fenglin; Cui Jie; Fu Huabin; Wang Jingzhou

    2007-01-01

    Inflammatory reaction plays an important role in cerebral ischemia-reperfusion injury, however, its mechanism is still unclear. Our study aims to explore the function of Toll-like receptor 4 (TLR4) in the process of cerebral ischemia-reperfusion. We made middle cerebral artery ischemia-reperfusion model in mice with line embolism method. Compared with C3H/OuJ mice, scores of cerebral water content, cerebral infarct size and neurologic impairment in C3H/Hej mice were obviously lower after 6 h ischemia and 24 h reperfusion. Light microscopic and electron microscopic results showed that cerebral ischemia-reperfusion injury in C3H/Hej mice was less serious than that in C3H/OuJ mice. TNF-α and IL-6 contents in C3H/HeJ mice were obviously lower than that in C3H/OuJ mice with ELISA. The results showed that TLR4 participates in the process of cerebral ischemia-reperfusion injury probably through decrease of inflammatory cytokines. TLR4 may become a new target for prevention of cerebral ischemia-reperfusion injury. Our study suggests that TLR4 is one of the mechanisms of cerebral ischemia-reperfusion injury besides its important role in innate immunity