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Aim To investigate the dynamic time-course changes in neuronal cytoskeleton after acute ischemia and reperfusion in rats. Methods Reperfusion was performedin rats by blocking the middle cerebralarteryfor 90 min, then therats wereobserved and collected at different time points. The brain damage wasobserved by Nissl staining,and neurobehavioural function was evaluated with neurological deficit score and forelimb placement test. The cellular changes in the alternations of cytoskeletal elements including microtubule associated protein 2 (MAP2) and neurofilament heavy chain (NF-H) were observed by immunohistochemistry staining and Western blot. Impaired axons, dendrites and cytoskeletal alternations were detected by electron microscope. Results Brain damage and neurobehavioural function were gradually aggravated with the prolongation of reperfusion. Brain damage appeared earlier and more severe in striatum than in cortex. Moreover, decreased MAP2-related and increased NF-H-related immunoreactive intensities were found in the ischemic areas. Impaired cytoskeletal arrangement and reduced dense were indicated. Damaged cytoskeletal components such as microtubules and neurofilament arrangement, decreased axonal filament density, and swelled dendrites were observed after cerebral ischemia reperfusion by ultrastructural observations. Conclusions Different brain regions have diverse tolerance to ischemia-reperfusion injury. Major elements of neuronal cytoskeleton show dynamic responses to ischemia and reperfusion, which may further contribute to brain damage and neurological impairment following MCAO and reperfusion.
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Aim To observe cellular damage and astrocyte activation at different time points of cerebral ischemia and reperfusion. Methods The middle cerebral artery of male SpragueDawley rats was occluded for 90 min followed by different time points of reperfusion. Eighty-five SPF male SD rats were randomly divided into control group (Sham), IR3, 6, 12, 24 and IR48h (MCAO followed by 48 h of reperfusion) group. Cerebral ischemia and reperfusion injury was observed by HE staining, and the structure of astrocytes was estimated with transmission electron microscopy (TEM). GFAP expression was detected by immunofluorescence staining and Western blot. Results Cerebral ischemia following by different time points of reperfusion led to different degrees of cellular damage, which was the most serious at 24 h of reperfusion. TEM showed destruction of astrocytes structure, swollen organelles and broken mitochondrial ridge. After cerebral ischemia-reperfusion, the expression levels of GFAP were significant up-regulated in the ischemic penumbra cortex and the highest was at 48 h of reperfusion, indicating astrocytes were activated. In addition, the results showed the gradual decrease in GFAP expression in the infarct core. Conclusions After cerebral ischemia-reperfusion, cellular damage is aggravated, and astrocytes are gradually activated in the ischemic penumbra. With the extension of reperfusion time, the boundaries of infarct area and ischemic area are gradually clear, and scarring may occur.
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Objective:To explore the effect of hyperbaric oxygen (HBO) on the blood-brain barrier via the silent information regulator 1 (SIRT1)/Forkhead box O1(FoxO1) signaling pathway after cerebral ischemia and reperfusion using a rat model.Methods:Forty Wistar rats were randomly assigned into sham, cerebral ischemia-reperfusion (CIR), CIR+ HBO and CIR+ HBO+ EX527 groups, each of 10. The cerebral ischemia-reperfusion model was established in all groups except the sham group by right middle cerebral artery occlusion using the modified thread-occlusion method. The sham group was not ligated. Both the CIR+ HBO and CIR+ HBO+ EX527 groups were given HBO 1, 9, 21, 45 and 69 hours after the reperfusion. The CIR+ HBO+ EX527 group was additionally injected with 5mg/kg of EX527(a SIRT1inhibitor) peritoneally 4, 12, 24, 48 and 72 hours after the reperfusion. Then 2% Evens blue (EB) was injected into the tail vein an hour before the rats were sacrificed. The content of EB and the expression of SIRT1, FoxO1, ZO-1, Occludin, Claudin-5 mRNA and their proteins were determined using spectrophotometry, reverse transcription-polymerase chain reactions and Western blotting.Results:The average EB content of the hippocampal brain tissue from the CIR, CIR+ HBO and CIR+ HBO+ EX527 rats was significantly greater than the Sham group′s average 72h after reperfusion. The average expression of SIRT1, FoxO1, ZO-1, Occludin and Claudin-5 mRNA and their proteins was significantly lower, with the CIR + HBO + EX 527 group′s average significantly lower than that of the CIR+ HBO group.Conclusions:HBO can increase the expression of tight junction protein via the SIRT1/FoxO1 pathway. It helps to protect the blood-brain barrier in CIR injury situations.
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Objective: In this work, rats isolated hearts were infused EPA before the ischemia period and during reperfusion for available get well in parameter relatives to redox reactions. Methods: The effect of EPA was tested on isolated hearts induced to ischemia and reperfusion, treatment occurred at different times (ischemia or reperfusion). Antioxidant capacity against peroxyl radicals, glutathione cysteine ligase activity, glutathione concentration, lactate dehydrogenase, and creatine kinase concentration was analyzed. Results: Hearts treated with eicosapentaenoic acid had the minor generation of species reactive oxygen and lipid damage after reperfusion. The GSH concentration was higher when the hearts were treated with eicosapentaenoic acid in the period of reperfusion. Conclusion: In conclusion, this study demonstrates that the dose of EPA (20µM) used before ischemia can act as a cardioprotective antioxidant molecule, prevented damage heart from ischemic and reperfusion injury
Objetivo: Neste trabalho, corações isolados de ratos foram infundidos com EPA antes do período de isquemia e durante a reperfusão para obtenção de melhora em parâmetros relativos às reações redox. Métodos: O efeito do EPA foi testado em corações isolados induzidos a isquemia e reperfusão, o tratamento ocorreu em diferentes momentos (isquemia ou reperfusão). A capacidade antioxidante contra os radicais peroxil, atividade da glutationa cisteína ligase, concentração de glutationa, lactato desidrogenase e concentração de creatina quinase foi analisada. Resultados: Corações tratados com ácido eicosapentaenóico tiveram a menor geração de espécies reativas de oxigênio e danos lipídicos após a reperfusão. A concentração de GSH foi maior quando os corações foram tratados com ácido eicosapentaenóico no período de reperfusão. Conclusão: Em conclusão, este estudo demonstra que a dose de EPA (20µM) utilizada antes da isquemia pode atuar como uma molécula antioxidante cardioprotetora, prevenindo danos ao coração por isquemia e lesão de reperfusão.
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Heart , Infarction , Ischemia , Oxidation-Reduction , Oxidoreductases , Reperfusion , Eicosapentaenoic Acid , Lactic Acid , GlutathioneABSTRACT
OBJECTIVE@#To study the protective mechanism of Chinese medicine Suxiao Jiuxin Pills (, SXJ) on myocardial ischemia and reperfusion (I/R) injury.@*METHODS@#Mouse myocardial I/R injury model was created by 30-min coronary artery occlusion followed by 24-h reperfusion, the mice were then divided into the sham group (n=7), the I/R group (n=13), the tirofiban group (TIR, positive drug treatment, n=9), and the SXJ group (n=11). Infarct size (IS), risk region (RR), and left ventricle (LV) were analyzed with double staining methods. In addition, H9C2 rat cardiomyocytes were cultured with NaSO to simulate I/R in vitro. The phosphorylation of extracellular regulated protein kinases1/2 (ERK1/2), protein kinase B (AKT), glycogen synthase kinase-3β (GSK3β), and protein expression of GATA4 in nucleus were detected with Western blot assay.@*RESULTS@#The ratio of IS/RR in SXJ and TIR groups were lower than that in I/R group (SXJ, 22.4% ±6.6%; TIR, 20.8%±3.3%; vs. I/R, 35.4%±3.7%, P<0.05, respectively). In vitro experiments showed that SXJ increased the NaSO-enhanced phosphorylation of AKT/GSK3β and nuclear expression of GATA4.@*CONCLUSION@#SXJ prevents myocardial I/R injury in mice by activating AKT/GSK3β and GATA4 signaling pathways.
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Methane is the simplest hydrocarbon, consisting of one carbon atom and four hydrogen atoms. It is abundant in marsh gas, livestock rumination, and combustible ice. Little is known about the use of methane in human disease treatment. Current research indicates that methane is useful for treating several diseases including ischemia and reperfusion injury, and inflammatory diseases. The mechanisms underlying the protective effects of methane appear primarily to involve anti-oxidation, anti-inflammation, and anti-apoptosis. In this review, we describe the beneficial effects of methane on different diseases, summarize possible mechanisms by which methane may act in these conditions, and discuss the purpose of methane production in hypoxic conditions. Then we propose several promising directions for the future research.
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Humans , Antioxidants/pharmacology , Apoptosis/drug effects , Inflammation/drug therapy , Ischemia/drug therapy , Methane/therapeutic use , Reperfusion Injury/drug therapyABSTRACT
Methane is the simplest hydrocarbon, consisting of one carbon atom and four hydrogen atoms. It is abundant in marsh gas, livestock rumination, and combustible ice. Little is known about the use of methane in human disease treatment. Current research indicates that methane is useful for treating several diseases including ischemia and reperfusion injury, and inflammatory diseases. The mechanisms underlying the protective effects of methane appear primarily to involve anti-oxidation, anti-inflammation, and anti-apoptosis. In this review, we describe the beneficial effects of methane on different diseases, summarize possible mechanisms by which methane may act in these conditions, and discuss the purpose of methane production in hypoxic conditions. Then we propose several promising directions for the future research.
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OBJECTIVE： To study the protective effects of Polygonum orientale extract on myocardial ischemia-reperfusion injury （MIRI） model rats， and to provide reference for it’s deeply development of medicinal source. METHODS： Totally 24 rats were randomly divided into sham operation group （normal saline）， model group （normal saline）， Compound danshen tablet group （positive group， 0.17 g/kg） and P. orientale extract group （86 g/kg， calculated by crude drug）， with 6 rats in each group. All groups were given drugs 2 mL/100 g intragastrically once a day. After 4 d of consecutive administration， MIRI model was induced by the left anterior descending branch of arteria coronaria in all groups except for sham operation group. 24 h after reperfusion， they were given related medicine again. After medication， the changes of electrocardiogram ST segment were monitored in each group. The plasma levels of LDH， CK-MB， CK， cTn-I， SOD and NO were detected in each group. The myocardial infarction rate in each group was calculated and the pathomorphological changes in the myocardium were observed. RESULTS： Compared with sham operation group， ST segment of myocardial electrocardiogram was increased in model group （P＜0.01）. The plasma levels of LDH， CK， CK-MB and cTn-I were increased significantly （P＜0.01）， while the plasma levels of SOD and NO were decreased significantly （P＜0.01）. The rate of myocardial infarction was increased significantly （P＜0.01）， and pathomorphological changes were observed in myocardial tissue such as infiltration of inflammatory cells and loose cytoplasm of cardiac myocytes. Compared with model group， ST segment of myocardial electrocardiogram was decreased significantly in Compound danshen tablet group and P. orientale extract group （P＜0.05）； the plasma levels of LDH， CK， CK-MB and cTn-I were decreased significantly （P＜0.05）， while the plasma levels of SOD and NO were increased significantly （P＜0.05）； the rate of myocardial infarction was decreased significantly （P＜0.05）， and inflammatory cell infiltration and tissue edema in myocardium were relieved to varying degrees. CONCLUSIONS： The protective effect of P. orientale extract protect on MIRI may be exerted by anti-oxidative damage.
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Objective@#To observe the effect of electroacupuncture on the volume of cerebral infarction, apoptosis of cerebral cells and the expression of protein kinase A (PKA) in the cerebral cortex of rats after ischemia and reperfusion so as to explore how electroacupuncture stimulates brain protection.@*Methods@#One hundred and twenty healthy, adult, male Sprague-Dawley rats were randomly divided into a sham operation group, a model group, an electroacupuncture group and an electroacupuncture with pre-stimulation group. All except the rats in the sham operation group received occulusion of the left middle cerebral artery using the intraluminal thread method for 2h and then reperfusion. Before the operation, the rats in the electroacupuncture with pre-stimulation group were given 30 minutes of electroacupuncture at the baihui, dazhui and right neiguan points every day for 5 days. After the operation both the electroacupuncture group and the pre-stimulated group were given that same electroacupuncture regimen. The other two groups received no special treatment. Garcia scoring was used to evaluate the neurological deficits of all of the rats 5 and 10 days after the intervention. Meanwhile, the ischemic volume, apoptosis of cortical cells and PKA-positive cells were determined using flow cytometry and immunohistochemistry after triphenyltetrazolium chloride (TTC) staining.@*Results@#The neurological function of the injured rats was severely impaired, while no neurological deficit was found in the sham operation group. The average Garcia score, cerebral infarction volume, cerebral apoptosis rate and PKA-positive cell expression rate of the electroacupuncture and electroacupuncture with pre-stimulation groups were all significantly better than those of the model group at the same time points. The averages of the electroacupuncture with pre-stimulation group were all significantly superior to those of the electroacupuncture group at the same time points.@*Conclusions@#Pre-stimulation using electroacupuncture can promote the recovery of injured nerves after cerebral ischemia and reperfusion, at least in rats. Electroacupuncture′s protective mechanism may be related to its reducing the infarcted volume, inhibiting apoptosis of brain cells and promoting PKA expression.
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Objective To investigate whether silencing repulsive guidance molecule A (KGMa) shows protective effects on blood brain barrier (BBB) and tight junction protein after the injury of cerebral ischemia and reperfusion (I/H) in rats. Methods Middle cerebral artery occlusion (MCAO)reperfusion was employed to establish the models in the male adult rats. Fourty male Sprague-Dawley rats were divided into blank control group (sh-con) and RGMa interference group (sh-RGMa). The effects of adenovirus on RGMa were observed at day 1 and day 3 after injection. The remaining 120 SD rats were randomly divided into sham group, I/R group, I/'R+sh-con group and I/R+sh-RGMa group. After reperfusion for 72 hours, the neurological recovery was evaluated in rats by neurological deficit score, the infarcted volume was measured by 2,3,5-triphenyl tetrazolium chloride (TTC) staining and the permeability of BBB was performed through evans blue by tail vein injection. The expression of RGMa was detected by Western blotting and immunohistochemistry assay. The expression of claudin-5, matrix metalloprotein 9 (MMP-9)and zonula occludin l(ZO-l)were detected by Western blotting. Results Silencing RGMa could improve the permeability of BBB, the infarcted volume, down-regulate the expression of MMP-9, and up-regulate the expression of claudin-5 and Z0-1. Conclusion Silencing RGMa shows protective effects on BBB after I/R injury in rats.
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Objective: To investigate the protective effects of the combination of Xuesaitong (XST) and aspirin on cerebral ischemia and reperfusion injury (CIRI) in rats, and further explore the underlying mechanisms. Methods: A total of 150 male Sprague-Dawley (SD) rats were randomly divided into five groups with 30 rats in each group: sham group, middle cerebral artery occlusion/reperfusion (MCAO/R) model group, XST group, aspirin group, and XST + aspirin group. Rats were pretreated with XST, aspirin, or XST + aspirin for 7 d. One hour after the last administration, a model of CIRI was induced by MCAO/R. Neurological deficits were assessed using Longa's five-point scale. Cerebral edema was detected by the measurement of brain water content. The volume of cerebral infarction was determined by 2,3,5-triphenyltetrazolium chloride (TTC) staining. The activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px), as well as levels of malonaldehyde (MDA) were detected by commercial kits. Enzyme-linked immunosorbent assay (ELISA) was used to determine the levels of interleukin-1 (IL-1β), interleukin-4 (IL-4), interleukin-6 (IL-6), interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-α), monocyte chemotactic protein 1 (MCP-1), and kynurenine in serum, cerebral cortex, and hippocampus of MCAO/R rats. The protein expression of nuclear factor erythroid 2-related factor (Nrf2), heme oxygenase-1 (HO-1), I-kappa B alpha (IκBα), and nuclear factor kappa B (NF-κB)/p65 in the cortex were analyzed by western blotting. Results: Treatment of XST, aspirin, and XST + aspirin significantly alleviated the neurological deficits, cerebral edema, and cerebral infarct volume induced by MCAO/R. Treatment of XST, aspirin, and XST + aspirin also reduced MDA, IL-1β IL-6,TNF-α MCP-1, and kynurenine levels, and increased SOD, CAT, GSH-Px, IL-4, and IL-10 levels in serum, cerebral cortex, and hippocampus of MCAO/R rats. Furthermore, treatment of XST, aspirin, and XST + aspirin decreased the expression of nuclear NF-κB/p65 and increased the expression of IκBα nuclear Nrf2, and HO-1. Importantly, the combination of XST and aspirin enhanced the protective effects of XST or aspirin treatment alone on CIRI in rats. Conclusion: The combination of XST and aspirin significantly inhibited oxidative stress and inflammation in serum, cerebral cortex, and hippocampus of MCAO/R rats. The combination of XST and aspirin exerted more protective effects than XST or aspirin treatment alone. The combination of XST and aspirin might provide the synergistic therapeutic effects on CIRI, and deserve further clinical investigation.
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<p><b>OBJECTIVE</b>To observe the in vivo effect of Danlou Tablet (, DLT) on myocardial ischemia and reperfusion (I/R) injury.</p><p><b>METHODS</b>DLT effects were evaluated in mouse heart preparation using 30-min coronary occlusion followed by 24-h reperfusion and compared among sham group (n=6), I/R group (n=8), IPC group (ischemia preconditioning, n=6) and DLT group (I/R with DLT pretreatment for 3 days, 750 mg•kg•day, n=8). The effects of DLT were characterized in infarction size (IS) compared with risk region (RR) and left ventricle using the Evans blue/triphenyltetrazolium chloride double dye staining method in vivo. Furthermore, the dose-dependent effect of DLT on I/R injury was evaluated by double staining method. Five different concentrations of DLT (0.625, 1.25, 2.5, 5 and 10 g•kg•day) were chosen in this study, and dose-response curve of DLT was obtained on these data.</p><p><b>RESULTS</b>The ratio of IS to left ventricle was significantly smaller in the DLT and IPC groups than the I/R group (P<0.05 or P<0.01), the ratio of IS to RR was also reduced in the DLT and IPC groups (P<0.01), while there were no differences in RR among the four groups (P>0.05). Experiments showed incidence of arrhythmias was reduced in the DLT group (P<0.01). Furthermore, DLT produced a dose-dependent inhibitory effect with a half maximal inhibitory concentration of 1.225 g•kg•day.</p><p><b>CONCLUSIONS</b>Our research concluded that DLT was effective in reducing I/R injury in mice, and provided experimental supports for the clinical use of DLT.</p>
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Animals , Male , Arrhythmias, Cardiac , Drug Therapy , Pathology , Body Temperature , Cardiotonic Agents , Pharmacology , Therapeutic Uses , Dose-Response Relationship, Drug , Drugs, Chinese Herbal , Pharmacology , Therapeutic Uses , Heart Rate , Heart Ventricles , Pathology , Mice, Inbred C57BL , Myocardial Reperfusion Injury , Drug Therapy , Pathology , Risk Factors , TabletsABSTRACT
<p><b>OBJECTIVE</b>To observe the effects of low-intensity pulsed ultrasound (LIPUS) pretreatment on pulmonary expression of high mobility group box-1 (HMGB1) in a rat model of lung ischemia-reperfusion (IR).</p><p><b>METHODS</b>Thirty-two male SpragueDawley rats weighing 250-300 g were randomly divided (=8) into sham-operated group, lung IR group, LIPUS pretreatment group and pretreatment with α7-nicotinic cholinergic receptor (α7nAChR) antagonist group. In the sham-operated group, the left pulmonary hilum was dissociated without occlusion; in the other 3 groups, the left pulmonary hilum was occluded for 45 min followed by reperfusion for 180 min; LIPUS pretreatment for 30 min and intraperitoneal injection of methyllycaconitine (2 mg/kg), an α7nAChR antagonist, were administered before the operation. The wet/dry weight ratio (W/D) and pulmonary permeability index (LPI) of the lung tissue were measured, and the lung histopathology was observed and scored. The contents of interleukin-1 (IL-1) and IL-6 in the lung tissues were measured using ELISA, and the pulmonary expression of HMGB1 protein was detected using immunofluorescence assay and Western blotting.</p><p><b>RESULTS</b>Compared with those in the sham-operated group, the W/D of the lung tissue, LPI, pathological scores, IL-1 and IL-6 contents in the lung tissue, and pulmonary HMGB1 expression all significantly increased in the other 3 groups ( < 0.05). LIPUS preconditioning significantly lowered the W/D values, LPI, pathological score, IL-1 and IL-6 contents and HMGB1 expression in the lung tissues following lung IR, and these effects were significantly inhibited by administration of methyllycaconitine.</p><p><b>CONCLUSIONS</b>LIPUS preconditioning can reduce lung IR injury possibly by activating α7nAChR-dependent cholinergic anti-inflammatory pathway to reduce lung tissue HMGB1 expression.</p>
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Abstract AIM To compare the amount of cardioprotection induced by a single exercise session with those achieved after an 8-week aerobic exercise training following ischemia reperfusion injury in rats. METHODS Twenty-five male Wistar rats (250-300g) were assigned into a group submitted to physical training (TR; n=12) or a single maximal exercise session (EXE; n=13). Following sedentarism or physical training (8 weeks, 5 sessions/wk, 1h/session at 70% of maximal speed) both groups performed a maximal exercise test. Then, groups were submitted to ischemia reperfusion injury (30 min/1h) through an isolated heart protocol, in which left ventricle developed pressure was measured. RESULTS The TR group presented greater maximal oxygen consumption compared to the EXE group (77.25±20.41 vs 41.32±25.86 ml/Kg/min; P=0.003). Regarding left ventricle developed pressure, no differences were detected between groups at baseline (TR: 89.78±24.40 vs EXE: 81.37±31.84 mmHg; P=0.48). However, after reperfusion, the TR group presented superior intraventricular pressure than EXE group (37.94±18.34 vs 21.59±13.67 mmHg; P=0.03). CONCLUSION Eight-week aerobic training induced greater cardioprotection against ischemia reperfusion injury in rats compared to a single exercise session, due to an increased cardiac function. This suggests that exercise-induced cardioprotection is a multifactorial process that may involve different mediators according to the exercise duration.(AU)
Subject(s)
Animals , Male , Rats , Exercise , Myocardial Reperfusion Injury/chemically induced , Rats, WistarABSTRACT
Objective To preliminarily reveal the neurovascular effect of electroacupuncture and adrenomedullin (ADM) in cerebral ischemia-reperfusion injury.Methods Rat changes after middle cerebral artery ischemia and reperfusion, and the effect of electroacupuncture and ADM on them were investigated using the neurological deficit score, somatosensory evoked potentials and TTC staining technique.Results Electroacupuncture and ADM can significantly improve the neurological deficit score after cerebral ischemia and reperfusion (P0.05). The P1-N1 and N1-P2 peak values of somatosensory evoked potentials decreased significantly at 30 min after ischemia (P0.05).Conclusions Electroacupuncture can reduce neurological impairment and improve brain blood supply after cerebral ischemia and reperfusion. That is similar to the neurovascular effect of ADM.
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Objective:To investigate the effects of high thoracic epidural anesthesia (HTEA) on the cerebral blood flow (CBF) and hippocampal apoptosis-related proteins Bcl-2 and Bax during global cerebral ischemia and reperfusion (GCI) in rats.Methods:Fifteen-minute global ischemia was established by 4-vessel occlusion and epidural catheterization was performed through T4-5 intervertebral spaces in adult male Wistar rats.According to the different drugs infused into the epidural space,the rats were randomly divided into four groups:Sham group (0.9 ％ NaC1),Sham-HTEA group (0.25 ％ bupivacaine),GCI group (global cerebral ischemia,0.9 ％ NaC1) and HTEA group (global cerebral ischemia,0.25 ％ bupivacaine).And 0.25 ％bupivacaine or 0.9 ％ saline (20 μL·h-1) was infused continuously to the thoracic epidural space from 15 minutes before ischemia to 24 hours after reperfusion.Mean arterial pressure (MAP),heart rate (HR) and cerebral blood flow (CBF) were determined until 2 hours after reperfusion,and the hippocampal Bcl-2 and Bax proteins at 24 hours after reperfusion were examined by Western-blot.Results:Compared with the GCI group,HTEA group has no significant difference on MAP and HR during ischemia and 2 hours after reperfusion,andcompared with the Sham group,MAP in GCI group increased in ischemia 0 min and decreased in reperfusion 0 min.The CBF in HTEA group was significantly lower than that in GCI group (123.1％± 35.2％ vs 177.5％± 32.4％,P＜0.01) in reperfusion 10 min,and higher than that in GCI group during the hypoperfusion of 60 to 120 minutes after reperfusion (P＜0.05),and the ratio of Bax/Bcl-2 in hippocampus was significantly decreased in HTEA group 24 hours after reperfusion (P＜0.01).Conclusions:Continuous HTEA infusion of 0.25 ％ bupivacaine 20 μL ·h-1 could maintain the hemodynamic stability,and improve the CBF of hypoperfusion period in rats,as well as reduce the ratio of Bax/Bcl-2 at 24 hours after reperfusion.
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Objective Ischemia reperfusion injury (IRI) is a major limiting factor of graft survival in organ transplantation.We've established a novel procedure called ischemia-free liver transplantation (IFLT) in big animal study.In this report,we aimed to investigate the feasibility and early outcomes of IFLT.Methods We have performed 3 cases of IFLT during July 23,2017 to August 9,2017.We analyzed the surgical methods,normothermic perfusion parameters,blood gas analysis,liver function tests and complications early after liver transplantation.Pathologic studies and immunohistochemical staining of donor liver biopsies were conducted before procurement,at the end of machine perfusion,as well as after re-vascularization for evaluating IRI.Results The surgical procedures of all 3 patients were successful,without stoppage of blood supply for the liver grafts throughout organ procurement,ex vivo preservation and implantation.During normothermic perfusion,the pH value was stable within the normal range and the lactate levels dropped quickly to lower than detected (＜0.3 mmol/L) within 1.5-3 h.The livers continued to produce bile with the volume of 2-6 mL/h.Hematoxylin and eosin (HE) staining evaluation and TdT-mediated dUTP nick end labeling (TUNEL) assay of biopsies taken from liver tissues before procurement,at the end of machine perfusion and after re-vascularization,showed few necrostic and apoptotic hepatocytes in the liver biopsies.The immunohistochemical staining of IL-1β and vWF suggested no inflammatory cytokine release and sinusoidal endothelial cell activation.The three patients recovered smoothly without rejection,vascular and biliary complications.Conclusion IFLT is a feasible and effective procedure,which is able to overcome the major limitations of conventional procedure.The novel IFLT will become one of the mainstream transplant procedures in the future.
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Objective To investigate the effect and mechanism of autophagy inhibited by Met/HGF passway in alleviating myocardial ischemia and reperfusion injury.Methods Lsolated cardiomyocytes of rats were divided into 5 groups:control group,ischemia and reperfusion (IR) group,Met-transfection group,Met siRNA-transfection group,Met-transfection and HGF activator group.Over or less expressions of Met were controlled by the method of transfection.Cell proteins were extracted after IR injury.The expression of cell protein such as met,HGF,AMPK,PI3K,autophagy-related protein LC3B,Beclin-1 and apoptosis-related protein Bcl-2 were detected by Western blot.Results Compared with control group,Western blot results showed that the expression of AMPK and PI3K increased significantly by the method of over expression of Met and activation of HGF,the expression of autophagy-related protein LC3B and Beclin-1 decreased significantly at the same time.However,it showed an opposite trend in IR group and Met siRNA-transfection group.Conclusion Activation of the Met/HGF signal pathway inhibits autophagy and attenuates myocardial ischemia-reperfusion injury.
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<p><b>OBJECTIVE</b>To analyze the effects of salvianolate on myocardial infarction in a murine in vivo model of ischemia and reperfusion (I/R) injury.</p><p><b>METHODS</b>Myocardial I/R injury model was constructed in mice by 30 min of coronary occlusion followed by 24 h of reperfusion and pretreated with salvianolate 30 min before I/R (SAL group). The SAL group was compared with SHAM (no I/R and no salvianolate), I/R (no salvianolate), and ischemia preconditioning (IPC) groups. Furthermore, an ERK1/2 inhibitor PD98059 (1 mg/kg), and a phosphatidylinositol-3-kinase (PI3-K) inhibitor, LY294002 (7.5 mg/kg), were administered intraperitoneal injection (i.p) for 30 min prior to salvianolate, followed by I/R surgery in LY and PD groups. By using a double staining method, the ratio of the infarct size (IS) to left ventricle (LV) and of risk region (RR) to LV were compared among the groups. Correlations between IS and RR were analyzed. Western-blot was used to detect the extracellular signal-regulated kinase 1/2 (ERK1/2) and protein kinase B (AKT) phosphorylation changes.</p><p><b>RESULTS</b>There were no significant differences between RR to LV ratio among the SHAM, I/R, IPC and SAL groups (P>0.05). The SAL and IPC groups had IS of 26.1%±1.4% and 22.3%±2.9% of RR, respectively, both of which were significantly smaller than the I/R group (38.5%±2.9% of RR, P<0.05, P<0.01, respectively). Moreover, the phosphorylation of ERK1/2 was increased in SAL group (P<0.05), while AKT had no significant change. LY294002 further reduced IS, whereas the protective role of salvianolate could be attenuated by PD98059, which increased the IS. Additionally, the IS was not linearly related to the RR (r=0.23, 0.45, 0.62, 0.17, and 0.52 in the SHAM, I/R, SAL, LY and PD groups, respectively).</p><p><b>CONCLUSION</b>Salvianolate could reduce myocardial I/R injury in mice in vivo, which involves an ERK1/2 pathway, but not a PI3-K signaling pathway.</p>
Subject(s)
Animals , Male , Blotting, Western , Cardiotonic Agents , Pharmacology , Therapeutic Uses , Flavonoids , Pharmacology , Heart Ventricles , Pathology , MAP Kinase Signaling System , Mice, Inbred C57BL , Mitogen-Activated Protein Kinase 1 , Metabolism , Mitogen-Activated Protein Kinase 3 , Metabolism , Myocardial Reperfusion Injury , Drug Therapy , Pathology , Organ Size , Phosphorylation , Plant Extracts , Chemistry , Pharmacology , Therapeutic Uses , Protein Kinase Inhibitors , Pharmacology , Staining and LabelingABSTRACT
Kidney ischemia and reperfusion injury (IRI) is associated with a high mortality rate, which is attributed to tubular oxidative and nitrative stresses; however, an effective approach to limit IRI remains elusive. Spermidine, a naturally occurring polyamine, protects yeast cells against aging through the inhibition of oxidative stress and necrosis. In the present study, spermidine supplementation markedly attenuated histological damage and kidney dysfunction during IRI. In addition, exogenous spermidine potently inhibited poly(ADP-ribose) polymerase 1 (PARP1) activation and DNA nitrative/oxidative stress following IRI. Conversely, inhibition of ornithine decarboxylase (ODC) via siRNA transfection in vivo significantly enhanced DNA nitration, PARP1 activation, and functional damage during IRI. Finally, in ODC knockdown kidneys, PARP1 inhibition attenuated histological and functional damage induced by IRI, but not DNA nitrative stress. In conclusion, these data suggest that spermidine protects kidneys against IRI through blocking DNA nitration and PARP1 activation and this finding provides a novel target for prevention of acute kidney injury including IRI.