Hydrogen-rich saline reduces lung injury induced by intestinal ischemia/reperfusion in rats

Objective. Hydrogen has been reported to selectively reduce the hydroxyl radical, the most cytotoxic of reactive oxygen species. In this study we investigated the effects of hydrogen-rich saline on the prevention of lung injury induced by intestinal ischemia/reperfusion (I/R) in rats. Methods. Male Sprague-Dawley rats (n = 30, 200-220 g) were divided randomly into three experimental groups: sham operated, intestinal I/R plus saline treatment (5 ml/kg, i.v.), and intestinal I/R plus hydrogen-rich saline treatment (5 ml/kg, i.v.) groups. Intestinal I/R was produced by 90 min of intestinal ischemia followed by a 4 h of reperfusion. Results. Hydrogen-rich saline treatment decreased the neutrophil infiltration, the lipid membrane peroxidation, NF-κB activation and the pro-inflammatory cytokine interleukin IL-1β and TNF-α in the lung tissues compared with those in saline-treated rat. Conclusion. Hydrogen-rich saline attenuates lung injury induced by intestinal I/R.     

Edaravone protects against lung injury induced by intestinal ischemia/reperfusion in rat

Intestinal ischemia/reperfusion (I/R) is a critical and triggering event in the development of distal organ dysfunction, frequently involving the lungs. Respiratory failure is a common cause of death and complications after intestinal I/R. In this study we investigated the effects of edaravone (3-methyl-1-phenyl-2-pyrazoline-5-one) on the prevention of lung injury induced by intestinal I/R in rats. Edaravone has been used for protection against I/R injury in patients with cerebral infarction. When rats were subjected to 180 min of intestinal ischemia, a high incidence of mortality was observed within 24 h. In this situation, intravenous administration of edaravone just before the start of reperfusion reduced the mortality in a dose-dependent manner. To examine the efficacy of edaravone on the lung injury induced by intestinal I/R in more detail, we performed 120 min of intestinal ischemia followed by 120 min of reperfusion. Edaravone treatment decreased the neutrophil infiltration, the lipid membrane peroxidation, and the expression of proinflammatory cytokine interleukin-6 mRNA in the lungs after intestinal I/R compared to the I/R-treated rat lungs without edaravone treatment. Histopathological analysis also indicated the effectiveness of edaravone. In conclusion, edaravone ameliorated the lung injury induced by intestinal I/R, resulting in a reduction in mortality.     

Anthocyanins from soybean seed coat inhibit the expression of TNF-alpha-induced genes associated with ischemia/reperfusion in endothelial cell by NF-kappaB-dependent pathway and reduce rat myocardial damages incurred by ischemia and reperfusion in vivo

We examined the inhibition of the expression of some inflammatory genes associated with ischemia-reperfusion (I/R) injury by anthocyanins isolated from black soybean seed coat in tumor necrosis factor-alpha (TNF-alpha)-treated bovine aortic endothelial cells. In addition, its potential use on I/R-injury was investigated using rats subjected to 30-min occlusion of left descending coronary artery followed by 24-h reperfusion. Western blot analysis and luciferase activity assay showed that anthocyanins inhibited TNF-alpha-induced vascular cell adhesion molecule-1, intracellular adhesion molecule-1, and cyclooxygenase-2 levels, which is through NF-kappaB-dependent pathway. Further, anthocyanins protected myocardiac injury from I/R in rats. It is suggested that anthocyanins from black soybean seed coat can be used as a useful drug to modulate cardiovascular disorder.     

细胞自噬在大鼠肺缺血/再灌注引发肝脏损伤中的作用*

目的: 探讨肺缺血/再灌注(LI/R)时肝脏损伤的影响,并初步探索细胞自噬(Autophagy)在其中发挥的作用。方法: 构建大鼠缺血/再灌注肺损伤(LI/RI)模型,模型制备方法为大鼠麻醉后切开气管进行机械通气,使用动脉夹将肺门夹闭模拟缺血过程,30 min后松开动脉夹,恢复灌注3 h。24只大鼠随机分为伪手术组(Sham组)、缺血/再灌注组(I/R组)、溶剂组(DMSO组)和自噬抑制剂组(3-MA组),每组均6只,后2组大鼠术前分别腹腔注射DMSO和3-MA,造模结束后使用肺湿/干重比判断造模是否成功;抽取静脉血测定肝脏转氨酶指标ALT与AST;取肝脏组织,光镜下观察肝脏形态改变,以及电镜下观察肝细胞超微结构;使用RT-qPCR和Western blot实验分别检测肝脏组织细胞中自噬相关蛋白的基因mRNA表达水平和蛋白表达水平。结果: 与Sham组相比,其余各组肺湿/干重比均升高;血AST和ALT均有大幅升高且肝脏组织损伤明显,其中以I/R组升高最为明显,光镜下组织形态学及电镜下细胞微细结构均有不同程度的破坏;肝脏中自噬相关蛋白的基因表达水平与蛋白表达水平均有明显不同,表现为自噬上升 (P＜0.01或P＜0.05)。I/R组和DMSO组肝脏组织均有较重损伤,肝细胞结构破坏严重,自噬小体形成,而AST、ALT、自噬相关蛋白转录和表达水平等各项指标均无统计学差异(P＞0.05)。而相较于DMSO组,3-MA组肝脏组织损伤有所减轻,肝细胞微细结构损伤程度低,且无自噬小体形成,血中AST和ALT下降,肝脏组织内自噬水平均下降 (P＜0.05)。结论: 肺缺血/再灌注可引起大鼠肝损伤;细胞自噬可介导大鼠肺缺血/再灌注引起的肝损伤,抑制细胞自噬可以有效减轻大鼠LI/R引起的肝损伤。     

Ischemic conditioning by short periods of reperfusion attenuates renal ischemia/reperfusion induced apoptosis and autophagy in the rat

Prolonged ischemia amplified iscehemia/reperfusion (IR) induced renal apoptosis and autophagy. We hypothesize that ischemic conditioning (IC) by a briefly intermittent reperfusion during a prolonged ischemic phase may ameliorate IR induced renal dysfunction. We evaluated the antioxidant/oxidant mechanism, autophagy and apoptosis in the uninephrectomized Wistar rats subjected to sham control, 4 stages of 15-min IC (I15 × 4), 2 stages of 30-min IC (I30 × 2), and total 60-min ischema (I60) in the kidney followed by 4 or 24 hours of reperfusion. By use of ATP assay, monitoring O₂ ^-. amounts, autophagy and apoptosis analysis of rat kidneys, I60 followed by 4 hours of reperfusion decreased renal ATP and enhanced reactive oxygen species (ROS) level and proapoptotic and autophagic mechanisms, including enhanced Bax/Bcl-2 ratio, cytochrome C release, active caspase 3, poly-(ADP-ribose)-polymerase (PARP) degradation fragments, microtubule-associated protein light chain 3 (LC3) and Beclin-1 expression and subsequently tubular apoptosis and autophagy associated with elevated blood urea nitrogen and creatinine level. I30 × 2, not I15 × 4 decreased ROS production and cytochrome C release, increased Manganese superoxide dismutase (MnSOD), Copper-Zn superoxide dismutase (CuZnSOD) and catalase expression and provided a more efficient protection than I60 against IR induced tubular apoptosis and autophagy and blood urea nitrogen and creatinine level. We conclude that 60-min renal ischemia enhanced renal tubular oxidative stress, proapoptosis and autophagy in the rat kidneys. Two stages of 30-min ischemia with 3-min reperfusion significantly preserved renal ATP content, increased antioxidant defense mechanisms and decreased ischemia/reperfusion enhanced renal tubular oxidative stress, cytosolic cytochrome C release, proapoptosis and autophagy in rat kidneys.     

Involvement of glutamate in retinal protection against ischemia/reperfusion damage induced by post-conditioning

Retinal ischemia could provoke blindness and there is no effective treatment against retinal ischemic damage. Brief intermittent ischemia applied during the onset of reperfusion (i.e., post-conditioning) protects the retina from ischemia/reperfusion injury. Multiple evidences support that glutamate is implicated in retinal ischemic damage. We investigated the involvement of glutamate clearance in post-conditioning-induced protection. For this purpose, ischemia was induced by increasing intra-ocular pressure for 40 min, and 5 min after reperfusion, animals underwent seven cycles of 1 min/1 min ischemia/reperfusion. One, three, or seven days after ischemia, animals were subjected to electroretinography and histological analysis. The functional and histological protection induced by post-conditioning was evident at 7 (but not 1 or 3) days post-ischemia. An increase in Müller cell glial fibrillary acidic protein (GFAP) levels was observed at 1, 3, and 7 days after ischemia, whereas post-conditioning reduced GFAP levels of Müller cells at 3 and 7 days post-ischemia. Three days after ischemia, a significant decrease in glutamate uptake and glutamine synthetase activity was observed, whereas post-conditioning reversed the effect of ischemia. The intravitreal injection of supraphysiological levels of glutamate mimicked electroretinographic and histological alterations provoked by ischemia, which were abrogated by post-conditioning. These results support the involvement of glutamate in retinal protection against ischemia/reperfusion damage induced by post-conditioning.     

右美托咪啶对肺缺血/再灌注诱发小鼠肾脏超微结构改变的影响

目的：评价右美托咪啶对小鼠肺缺血/再灌注诱发肾脏损伤的影响。方法：雄性健康SPF级C57BL/6J小鼠50只,体重20 g~24 g,8~10周龄,采用随机数字表法,将其分为5组（n=10）：假手术组（sham组）、肺缺血/再灌注损伤组（I/R组）、肺缺血/再灌注+生理盐水组（NS组）、右美托咪啶组（Dex组）、右美托咪啶+阿替美唑（Atip）（DA组）。采用小鼠在体左侧肺门夹闭30 min再灌注180 min方法制备肺缺血/再灌注损伤（I/R）模型。Dex组在肺门阻断前30 min腹腔注射右美托咪啶20 μg/kg,NS组为用同Dex组等体积的生理盐水替代Dex,DA组腹腔注射右美托咪啶（20 μg/kg）+阿替美唑（250 μg/kg）,其余处理同I/R组。再灌注结束后静脉取血ELISA法检测血浆中IL-1β和TNF-α浓度;取双肾组织,透射电镜下观察肾组织病理学结果。结果：与对照组相比,其余组血浆IL-1β和TNF-α浓度明显升高,肾组织病理学损伤明显加重;与I/R、NS、DA组相比,Dex组IL-1β和TNF-α浓度明显下降,差异有统计学意义（P<0.05）,且肾组织超微结构损伤有所减轻。结论：右美托咪啶预先给药可减轻小鼠肺缺血/再灌注诱发肾脏损伤,其机制可能与抑制炎性反应有关。     

青藤碱抗大鼠肝脏缺血/再灌注损伤作用的机制探讨

目的:观察青藤碱时大鼠肝脏缺血再灌注损伤的影响,探讨其保护大鼠肝脏缺血再灌注损伤作用的机制.方法:通过建立大鼠全肝缺血再灌注损伤模型,应用硝酸酶还原法测定肝脏缺血再灌注后60min血清NO水平变化;测定再灌注60 min后肝组织内MDA和SOD含量变化;再灌注60min取肝组织完成肝组织显微结构的观察.结果:肝脏缺血再灌注损伤后血清NO水平降低;青藤碱能提高再灌注后血清NO水平,且能改善肝脏缺血再灌注损伤的微循环,减轻肝细胞内超微结构的损害程度.结论:青藤碱对大鼠肝脏缺血再灌注损伤有保护作用,其主要作用机制是清除氧自由基和改善微循环.     

Oleuropein prevents oxidative myocardial injury induced by ischemia and reperfusion

The potential protective effects of oleuropein, a dietary antioxidant of olive oil, has been investigated in the isolated rat heart. The organs were subjected to 30 minutes of no-flow global ischemia and then reperfused. At different time intervals, the coronary effluent was collected and assayed for creatine kinase activity as well as for reduced and oxidized glutathione. In addition, the extent of lipid peroxidation was evaluated by measuring thiobarbituric acid reactive substance concentration in cardiac muscle. Pretreatment with 20 microg/g oleuropein before ischemia resulted in a significant decrease in creatine kinase and reduced glutathione release in the perfusate. The protective effect of oleuropein against the post-ischemic oxidative burst was investigated by measuring the release, in the coronary effluent, of oxidized glutathione, a sensitive marker of heart's exposure to oxidative stress. Reflow in ischemic hearts was accompanied by a prompt release of oxidized glutathione; in ischemic hearts pretreated with oleuropein, this release was significantly reduced. Membrane lipid peroxidation was also prevented by oleuropein. The reported data provide the first experimental evidence of a direct cardioprotective effect of oleuropein in the acute events that follow coronary occlusion, likely because of its antioxidant properties. This finding strengthens the hypothesis that the nutritional benefit of olive oil in the prevention of coronary heart disease can be also related to the high content of oleuropein and its derivatives. Moreover, our data, together with the well documented antithrombotic and antiatherogenic activity of olive oil polyphenols, indicate these antioxidants as possible therapeutic tools for the pharmacological treatment of coronary heart disease as well as in the case of cardiac surgery, including transplantation.     

川芎嗪对脑缺血/再灌注后所致肺损伤的影响

目的：观察川芎嗪对脑缺血／再灌注后肺损伤的影响。方法：采用Pulsinelli等的方法建立大鼠急性全脑缺血／再灌注模型。将Wistar大鼠随机分为三组,即：对照组（Control）、缺血／再灌注组（I／R）、川芎嗪＋缺血／再灌注组（TEP＋I／R）,分别测定各组肺功能（PaO2、PaCO2）,肺系数（LI％）、血浆和肺组织中与自由基有关物质的含量。结果：川芎嗪可有效改善脑缺血／再灌注后肺功能,减轻肺水肿,减少胞浆酶的漏出,增加自由基清除醇的活性,抑制组织脂质过氧化的发生。结论：川芎嗪对脑缺血／再灌注后肺损伤具有保护作用,其机制可能与其抗氧自由基和膜保护作用有关。     

Expression of bystin in reactive astrocytes induced by ischemia/reperfusion and chemical hypoxia in vitro

In this study, we investigated the effects of ischemia/reperfusion and chemical hypoxia on the morphology, cell viability and expression of bystin and glial fibrillary acidic protein (GFAP) in primary cultured astrocytes which were prepared by the subculture method. The astrocytes in Hank's medium without glucose and serum (oxygen-glucose deprivation, ischemic cells) were first exposed to 1% O2 and then to 21% O2 (normoxia), or treated with different concentrations of CoCl2 or NaN3 for different periods. Relevant observations and measurements were then conducted. The findings showed that treatment with 1% O2 for 0.5 or 3 h could induce a characteristic 'reactive' morphology and a significant increase in cell viability and total protein amount. The western blot analysis showed that treatment with 1% O2 for 0.5 or 3 h also induced a significant increase in the expression of bystin and that the response of bystin to mild ischemia was much more sensitive than that of GFAP. Similar results were also found in the cells treated with mild chemical hypoxia. The data demonstrated for the first time that mild ischemia and hypoxia could activate astrocytes and that bystin is a much more sensitive marker in activated astrocytes induced by ischemia and hypoxia as compared to GFAP. The significant up-regulation of bystin suggests that bystin may play an important role in the activation of astrocytes as well as in the neuroprotective role of hypoxic and ischemic preconditioning.     

Renal ischemia/reperfusion injury inhibits differentiation of dendritic cells derived from bone marrow monocytes in rats

Dendritic cells (DCs) are impacted by surgical injury, exercise, and other physiological stressors. This study aims to determine whether renal I/R injury affects 1) the differentiation of myeloid DCs from bone marrow monocytes (BMMos) and the maturation and activation state of these DCs and 2) DC infiltration of kidney. Sprague-Dawley rats were subjected to I/R injury or sham-operated. Creatinine clearance was monitored daily during the 14 d of reperfusion that followed the ischemic insult. At 2 and 14 d of reperfusion, the following were assessed 1) properties of BMMo-derived DCs (i.e., the amount of generated DCs, differentiation state markers [CD11c, CD80, CD86, and Ia], and functional state [MLR and amount of IL-12 produced]), and 2) the presence of DCs in the kidney. Numbers of BMMo-derived DCs were significantly decreased in the I/R injured group (compared with the sham-operated group) at 2 d but not 14 d. A comparison of the their functionality found mixed lymphocyte response [MLR] and IL-12 production were similar in the two groups at both time points. Also, immunohistochemistry showed infiltrating DCs in the outer medulla of the I/R injured kidney at 2 d but not 14 d of reperfusion. Thus, I/R stress reduces the number of DCs differentiated from BMMos but not the functional activity of these DCs. This decrease may reflect a stress-induced downshift in the capacity of BMMos to differentiate into DCs and a parallel upshift in the capacity of DCs to infiltrate the kidney.     

心肌缺血预适应循环血中微囊泡对大鼠心肌I/R损伤的作用

目的：研究心肌缺血预适应（IPC）大鼠循环血中微囊泡（MVs）对大鼠在体心肌缺血/再灌注（I/R）损伤的作用及相关机制。方法：反复短暂结扎/松开大鼠冠状动脉左前降支建立大鼠IPC模型,自腹主动脉取血,超速离心法分离循环血中的IPC-MVs,并对其进行流式鉴定。建立在体大鼠心肌I/R模型,股静脉注射IPC-MVs 7 mg/kg。HE染色观察心肌形态学变化,TTC染色检测心肌梗死范围,TUNEL染色检测心肌细胞凋亡率。比色法测定血清乳酸脱氢酶（LDH）活力,分光光度法测定心肌组织caspase 3活力,Western blot法检测心肌组织Bcl-2、Bax蛋白表达水平。结果：流式细胞术检测IPC-MVs浓度为4380±745个/μl。与I/R组比较,IPC-MVs能够减轻I/R大鼠心肌组织损伤,缩小心肌梗死范围（P<0.01）,减少心肌细胞凋亡数量（P<0.01）,明显降低血清LDH活力（P<0.01）,降低心肌组织caspase 3活力（P<0.01）,升高Bcl-2蛋白表达（P<0.01）,降低Bax蛋白表达（P<0.01）,升高Bcl-2/Bax比值（P<0.01）。结论：IPC-MVs显著减轻大鼠在体心肌I/R损伤,通过上调心肌组织中Bcl-2的蛋白表达,下调Bax的蛋白表达,升高Bcl-2/Bax比值,降低caspase 3活力而发挥心肌保护作用。     

Propofol protects the autophagic cell death induced by the ischemia/reperfusion injury in rats

Autophagy has been implicated in cardiac cell death during ischemia/reperfusion (I/R). In this study we investigated how propofol, an antioxidant widely used for anesthesia, affects the autophagic cell death induced by the myocardial I/R injury. The infarction size in the myocardium was dramatically reduced in rats treated with propofol during I/R compared with untreated rats. A large number of autophagic vacuoles were observed in the cardiomyocytes of I/R-injured rats but rarely in I/R-injured rats treated with propofol. While LC3-II formation, an autophagy marker, was up-regulated in the I/R-injured myocardium, it was significantly down-regulated in the myocardial tissues of I/R-injured and propofol-treated rats. Moreover, propofol inhibited the I/R-induced expression of Beclin-1, and it accelerated phosphorylation of mTOR during I/R and Beclin-1/Bcl-2 interaction in cells, which indicates that it facilitates the inhibitory pathway of autophagy. These data suggest that propofol protects the autophagic cell death induced by the myocardial I/R injury.     

七叶皂苷钠对肠缺血/再灌注肠过氧化损伤的影响

目的：探讨七叶皂苷钠对肠缺血/再灌注肠过氧化损伤的影响及其机制。方法：复制大鼠肠缺血/再灌注（I/R）损伤模型,观察七叶皂苷钠对血浆和肠组织超氧化物歧化酶（SOD）、丙二醛（MDA）、二胺氧化酶（DAO）、髓过氧化物酶（MPO）的影响,同时观察肠组织水肿和病理损害。结果：七叶皂苷钠可显著改善肠损伤,降低肠组织湿/干比值及含水率,同时升高血浆和肠组织SOD活性,降低血浆和肠组织MPO活性及MDA含量（P〈0.01）。结论：七叶皂苷钠对肠I/R后肠黏膜具有保护作用,其机制可能与抑制中性粒细胞的聚集与活化,对抗脂质过氧化损伤有关。     

Effect of stobadine on cardiac injury induced by ischemia and reperfusion

The aim of this work was to evaluate the effect of the antioxidant stobadine on ischemia/reperfusion-induced injury of the isolated rat heart. Experiments were performed according to Langendorff. Ischemia was induced by stop-flow lasting 30 minutes and the duration of repefusion was 30 minutes. Reperfusion of the ischemic heart induced dysrhythmias, with the most severe ones occurring in the first minutes of reperfusion. A significant increase in coronary perfusion pressure was observed starting after 15 min of reperfusion. Stobadine (10(-6) M applied 3 minutes before onset of ischemia and during reperfusion) prevented the deleterious effects to develop fully. The protective effect of stobadine observed in our experiments seems to be a consequence of its antioxidant properties.