VEGF对缺血/再灌注损伤胰腺细胞凋亡的影响

目的 研究血管内皮生长因子(VEGF)对缺血/再灌注损伤胰腺组织细胞凋亡的影响.方法 将雄性sD大鼠30只随机分为3组(n=10),A组为假手术组,B组为缺血/再灌注损伤组,C组为缺血/再灌注损伤+VEGF反义寡核苷酸组.通过血管夹阻断大鼠腹腔干及肠系膜上动脉30 min,然后去除血管夹再灌注6 h,建立大鼠胰腺缺血/再灌注损伤模型.对各组胰腺组织进行VEGF免疫组化染色及TUNEL法细胞凋亡检测.结果 缺血/再灌注损伤后胰腺组织出现细胞凋亡,同时VEGF蛋白表达上调.缺血/再灌注损伤+VEGF反义寡核苷酸组的胰腺组织VEGF蛋白表达较缺血/再灌注损伤组显著减少(P<0.05),前者细胞凋亡指数较后者明显升高(P<0.05).结论 VEGF能抑制缺血/再灌注损伤胰腺细胞凋亡,可能对胰腺缺血再灌注损伤具有保护作用.     

缺血处理对大鼠缺血再灌损伤性压疮的保护作用

目的通过建立大鼠压疮缺血再灌注损伤缺血处理模型,比较压疮缺血再灌注损伤预处理、后处理及联合处理方法对大鼠皮肤及皮下组织的保护作用,为临床判断压疮损伤的程度及压疮干预效果提供理论依据。 方法将100只SD大鼠随机分为对照组、缺血再灌注组和缺血预处理组、缺血后处理组、缺血联合处理组,每组20只建立大鼠压疮缺血再灌注损伤处理模型,通过肉眼观察受压程度,检测血清氧自由基的水平,判断压疮缺血再灌注损伤程度。 结果缺血再灌注组、缺血预处理组、缺血后处理组及缺血联合处理组大鼠出现Ⅰ期压疮的发生率为100%;缺血预处理和后处理组血清一氧化氮、丙二醛含量均高于对照组,明显低于缺血再灌注组,超氧化物歧化酶活性低于对照组,明显高于缺血再灌注组(P<0.01)。 结论缺血处理对压疮缺血再灌损伤性具有保护作用。     

VEGF对缺血/再灌注损伤胰腺细胞凋亡的影响

目的 研究血管内皮生长因子(VEGF)对缺血/再灌注损伤胰腺组织细胞凋亡的影响.方法 将雄性sD大鼠30只随机分为3组(n=10),A组为假手术组,B组为缺血/再灌注损伤组,C组为缺血/再灌注损伤+VEGF反义寡核苷酸组.通过血管夹阻断大鼠腹腔干及肠系膜上动脉30 min,然后去除血管夹再灌注6 h,建立大鼠胰腺缺血/再灌注损伤模型.对各组胰腺组织进行VEGF免疫组化染色及TUNEL法细胞凋亡检测.结果 缺血/再灌注损伤后胰腺组织出现细胞凋亡,同时VEGF蛋白表达上调.缺血/再灌注损伤+VEGF反义寡核苷酸组的胰腺组织VEGF蛋白表达较缺血/再灌注损伤组显著减少(P<0.05),前者细胞凋亡指数较后者明显升高(P<0.05).结论 VEGF能抑制缺血/再灌注损伤胰腺细胞凋亡,可能对胰腺缺血再灌注损伤具有保护作用.     

VEGF对缺血/再灌注损伤胰腺细胞凋亡的影响

目的 研究血管内皮生长因子(VEGF)对缺血/再灌注损伤胰腺组织细胞凋亡的影响.方法 将雄性sD大鼠30只随机分为3组(n=10),A组为假手术组,B组为缺血/再灌注损伤组,C组为缺血/再灌注损伤+VEGF反义寡核苷酸组.通过血管夹阻断大鼠腹腔干及肠系膜上动脉30 min,然后去除血管夹再灌注6 h,建立大鼠胰腺缺血/再灌注损伤模型.对各组胰腺组织进行VEGF免疫组化染色及TUNEL法细胞凋亡检测.结果 缺血/再灌注损伤后胰腺组织出现细胞凋亡,同时VEGF蛋白表达上调.缺血/再灌注损伤+VEGF反义寡核苷酸组的胰腺组织VEGF蛋白表达较缺血/再灌注损伤组显著减少(P<0.05),前者细胞凋亡指数较后者明显升高(P<0.05).结论 VEGF能抑制缺血/再灌注损伤胰腺细胞凋亡,可能对胰腺缺血再灌注损伤具有保护作用.     

VEGF对缺血/再灌注损伤胰腺细胞凋亡的影响

目的 研究血管内皮生长因子(VEGF)对缺血/再灌注损伤胰腺组织细胞凋亡的影响.方法 将雄性sD大鼠30只随机分为3组(n=10),A组为假手术组,B组为缺血/再灌注损伤组,C组为缺血/再灌注损伤+VEGF反义寡核苷酸组.通过血管夹阻断大鼠腹腔干及肠系膜上动脉30 min,然后去除血管夹再灌注6 h,建立大鼠胰腺缺血/再灌注损伤模型.对各组胰腺组织进行VEGF免疫组化染色及TUNEL法细胞凋亡检测.结果 缺血/再灌注损伤后胰腺组织出现细胞凋亡,同时VEGF蛋白表达上调.缺血/再灌注损伤+VEGF反义寡核苷酸组的胰腺组织VEGF蛋白表达较缺血/再灌注损伤组显著减少(P<0.05),前者细胞凋亡指数较后者明显升高(P<0.05).结论 VEGF能抑制缺血/再灌注损伤胰腺细胞凋亡,可能对胰腺缺血再灌注损伤具有保护作用.     

VEGF对缺血/再灌注损伤胰腺细胞凋亡的影响

目的 研究血管内皮生长因子(VEGF)对缺血/再灌注损伤胰腺组织细胞凋亡的影响.方法 将雄性sD大鼠30只随机分为3组(n=10),A组为假手术组,B组为缺血/再灌注损伤组,C组为缺血/再灌注损伤+VEGF反义寡核苷酸组.通过血管夹阻断大鼠腹腔干及肠系膜上动脉30 min,然后去除血管夹再灌注6 h,建立大鼠胰腺缺血/再灌注损伤模型.对各组胰腺组织进行VEGF免疫组化染色及TUNEL法细胞凋亡检测.结果 缺血/再灌注损伤后胰腺组织出现细胞凋亡,同时VEGF蛋白表达上调.缺血/再灌注损伤+VEGF反义寡核苷酸组的胰腺组织VEGF蛋白表达较缺血/再灌注损伤组显著减少(P<0.05),前者细胞凋亡指数较后者明显升高(P<0.05).结论 VEGF能抑制缺血/再灌注损伤胰腺细胞凋亡,可能对胰腺缺血再灌注损伤具有保护作用.     

VEGF对缺血/再灌注损伤胰腺细胞凋亡的影响

目的 研究血管内皮生长因子(VEGF)对缺血/再灌注损伤胰腺组织细胞凋亡的影响.方法 将雄性sD大鼠30只随机分为3组(n=10),A组为假手术组,B组为缺血/再灌注损伤组,C组为缺血/再灌注损伤+VEGF反义寡核苷酸组.通过血管夹阻断大鼠腹腔干及肠系膜上动脉30 min,然后去除血管夹再灌注6 h,建立大鼠胰腺缺血/再灌注损伤模型.对各组胰腺组织进行VEGF免疫组化染色及TUNEL法细胞凋亡检测.结果 缺血/再灌注损伤后胰腺组织出现细胞凋亡,同时VEGF蛋白表达上调.缺血/再灌注损伤+VEGF反义寡核苷酸组的胰腺组织VEGF蛋白表达较缺血/再灌注损伤组显著减少(P<0.05),前者细胞凋亡指数较后者明显升高(P<0.05).结论 VEGF能抑制缺血/再灌注损伤胰腺细胞凋亡,可能对胰腺缺血再灌注损伤具有保护作用.     

VEGF对缺血/再灌注损伤胰腺细胞凋亡的影响

目的 研究血管内皮生长因子(VEGF)对缺血/再灌注损伤胰腺组织细胞凋亡的影响.方法 将雄性sD大鼠30只随机分为3组(n=10),A组为假手术组,B组为缺血/再灌注损伤组,C组为缺血/再灌注损伤+VEGF反义寡核苷酸组.通过血管夹阻断大鼠腹腔干及肠系膜上动脉30 min,然后去除血管夹再灌注6 h,建立大鼠胰腺缺血/再灌注损伤模型.对各组胰腺组织进行VEGF免疫组化染色及TUNEL法细胞凋亡检测.结果 缺血/再灌注损伤后胰腺组织出现细胞凋亡,同时VEGF蛋白表达上调.缺血/再灌注损伤+VEGF反义寡核苷酸组的胰腺组织VEGF蛋白表达较缺血/再灌注损伤组显著减少(P<0.05),前者细胞凋亡指数较后者明显升高(P<0.05).结论 VEGF能抑制缺血/再灌注损伤胰腺细胞凋亡,可能对胰腺缺血再灌注损伤具有保护作用.     

VEGF对缺血/再灌注损伤胰腺细胞凋亡的影响

目的 研究血管内皮生长因子(VEGF)对缺血/再灌注损伤胰腺组织细胞凋亡的影响.方法 将雄性sD大鼠30只随机分为3组(n=10),A组为假手术组,B组为缺血/再灌注损伤组,C组为缺血/再灌注损伤+VEGF反义寡核苷酸组.通过血管夹阻断大鼠腹腔干及肠系膜上动脉30 min,然后去除血管夹再灌注6 h,建立大鼠胰腺缺血/再灌注损伤模型.对各组胰腺组织进行VEGF免疫组化染色及TUNEL法细胞凋亡检测.结果 缺血/再灌注损伤后胰腺组织出现细胞凋亡,同时VEGF蛋白表达上调.缺血/再灌注损伤+VEGF反义寡核苷酸组的胰腺组织VEGF蛋白表达较缺血/再灌注损伤组显著减少(P<0.05),前者细胞凋亡指数较后者明显升高(P<0.05).结论 VEGF能抑制缺血/再灌注损伤胰腺细胞凋亡,可能对胰腺缺血再灌注损伤具有保护作用.     

VEGF对缺血/再灌注损伤胰腺细胞凋亡的影响

目的 研究血管内皮生长因子(VEGF)对缺血/再灌注损伤胰腺组织细胞凋亡的影响.方法 将雄性sD大鼠30只随机分为3组(n=10),A组为假手术组,B组为缺血/再灌注损伤组,C组为缺血/再灌注损伤+VEGF反义寡核苷酸组.通过血管夹阻断大鼠腹腔干及肠系膜上动脉30 min,然后去除血管夹再灌注6 h,建立大鼠胰腺缺血/再灌注损伤模型.对各组胰腺组织进行VEGF免疫组化染色及TUNEL法细胞凋亡检测.结果 缺血/再灌注损伤后胰腺组织出现细胞凋亡,同时VEGF蛋白表达上调.缺血/再灌注损伤+VEGF反义寡核苷酸组的胰腺组织VEGF蛋白表达较缺血/再灌注损伤组显著减少(P<0.05),前者细胞凋亡指数较后者明显升高(P<0.05).结论 VEGF能抑制缺血/再灌注损伤胰腺细胞凋亡,可能对胰腺缺血再灌注损伤具有保护作用.     

Role of free radicals in failure of fatty liver grafts caused by ethanol.

Alcohol is associated with accidental deaths and suicides leading to organ donation, and hepatic steatosis is an important risk factor for initial poor function and failure of human liver grafts. Mechanisms of fatty graft failure are not fully understood, but increased oxidative stress may be a major factor. To characterize the role of free radical stress and the efficacy of antioxidant treatments in fatty liver graft injury, donors for orthotopic rat liver transplantation were treated chronically (3 or more weeks) and acutely (single dose) with ethanol. After transplantation, necrosis and alanine aminotransferase release were threefold to fourfold higher in recipients of fatty grafts from donors treated with ethanol either acutely or chronically compared with findings for recipients of grafts from untreated donors. Moreover, graft survival decreased from nearly 100% to less than 20%. Free radical adducts, as measured by electron spin resonance spectroscopy, were detected in the blood and bile of rats receiving fatty grafts caused by ethanol. Markers of lipid peroxidation also increased after transplantation. Destruction of Kupffer cells with gadolinium chloride decreased free radical production and improved graft survival. Leukocyte adhesion increased beginning early after implantation, and adherent white blood cells obtained from transplanted fatty livers produced the same free radical species as were detected in blood. Therefore, Kupffer cells and adherent white blood cells are important sources of free radicals. Free radicals not only damage fatty grafts directly but also lead to enhanced inflammation and disturbed microcirculation. Delivery of superoxide dismutase-1 and superoxide dismutase-2 genes, free radical-scavenging polyphenols, and antioxidant-containing Carolina Rinse solution reduced injury and improved survival of fatty grafts caused by ethanol. Taken together, these findings indicate that free radicals increase in fatty grafts after transplantation and play an important role in injury of fatty grafts obtained from ethanol-exposed donors. Treatment of fatty donor livers with antioxidants and free radical scavengers may thus be an effective clinical therapy to prevent failure of fatty grafts.     

内镜下双支架治疗肝移植术后胆管狭窄

目的：探讨内镜下胆道塑料双支架治疗肝移植术后胆管狭窄的应用价值。方法：回顾性分析2005年1月-2008年12月35例肝移植胆管狭窄经内镜胆道双支架治疗的临床资料。结果：全组35例均成功放置胆道塑料双支架。28例治疗有效;3例拔管后3月部分胆管再狭窄,再次内镜下置入胆道双支架;4例合并肝内胆管狭窄疗效不明显,长期置管。术后高淀粉酶血症5例,胆管炎7例,经保守治疗治愈。结论内镜下胆道塑料双支架治疗肝移植术后胆管吻合口狭窄是安全有效的治疗方法。     

双重血流同时开放对大鼠肝移植胆管TNF-α表达的影响

目的探讨门静脉、肝动脉双重血流同时开放对大鼠肝移植胆道缺血／再灌注（I／R）损伤中的TNF-α表达的影响。方法选用雄性SD大鼠建立大鼠自体原位肝移植模型，随机分为双重血流同时开放组（P组）、门静脉先开放组（N组）和假手术对照组（S组）。供肝再灌注后检测血清ALT、AST、GGT、AKP、TBiL及DBiL水平，比色法测定髓过氧化物酶（MPO）含量，RT-PCR法检测胆管组织TNF-α mRNA表达。结果肝脏再灌注后6h及24h两个时点P组的GGT水平明显低于N组水平（P〈0.05）；肝脏再灌注后24h，P组的AKP、TBiL、DBiL水平及胆管损伤病理学评分明显低于N组水平（P〈0．05）；再灌注后6h，N组大鼠肝组织的MPO含量明显高于P组（P〈0．05）；供肝再灌注后2h、6h，P组大鼠肝组织TNF-α mRNA的相对表达水平明显低于N组（P〈0．05）。结论门静脉、肝动脉双重血流同时开放，有利于减轻肝移植物胆管组织的I／R损伤；其机制可能与TNF-α表达水平的降低以及中性粒细胞（PMN）浸润的减少有关。     

Glutamine preserves cardiomyocyte viability and enhances recovery of contractile function after ischemia-reperfusion injury

BACKGROUND: Glutamine has been shown to protect against cellular injury in in vitro gut epithelial cells and in vivo in the septic rat. Glutamine's effect on the cardiomyocyte has not been explored. We tested the hypothesis that glutamine can enhance heat shock protein 72 (HSP 72) expression, attenuate intracellular oxidant generation, and protect cardiomyocytes against ischemia/reperfusion (I/R) injury. METHODS: Chicken cardiomyocytes were supplemented with glutamine (10 mmol/L) or were controls (0 mmol/L). Cells underwent I/R, and HSP 72 content was evaluated using Western blotting. Reactive oxygen species generation was quantified through 2'-7'-dichlorofluorescin diacetate oxidation. Cell viability was quantified using propidium iodide staining. Return of contractile function was analyzed through phase contrast microscopy. RESULTS: Glutamine significantly increased cardiomyocyte HSP 72 expression and markedly reduced cell death after I/R injury. Glutamine did not significantly decrease intracellular oxidant generation. Contractile function returned in all glutamine-treated cells versus none of the control cells postreperfusion. CONCLUSIONS: Glutamine significantly increases cardiomyocytes survival and recovery of contractile function after I/R injury. This protection is associated with enhanced HSP 72 expression. These observations suggest that glutamine may prove beneficial as a protective therapy in patients at risk for cardiac ischemia and reperfusion injury, such as patients undergoing procedures requiring cardiopulmonary bypass and patients with coronary artery disease.     

Antioxidant capability and efficacy of Mega-H silica hydride,an antioxidant dietary supplement,by in vitro cellular analysis using photosensitization and fluorescence detection

Treatment of Chinese hamster ovary and mouse hybridoma cells with Mega-H brand silica hydride, a marketed antioxidant, after photosensitization with singlet oxygen and hydroxyl/superoxide reactive oxygen species through the use of rose bengal diacetate and malachite green resulted in an effective method of reducing free radical activity by more than 96% against singlet oxygen species and more than 86% for hydroxyl and superoxide free radicals with the dosage recommended by the manufacturer. The analysis used a combinational spectrafluorometric technique to determine cell viability and cytotoxicity through the mechanism of intracellular esterase activity and plasma membrane integrity. Photosensitized controls not treated with silica hydride showed less than 1% viability under the same conditions. The reduction of the introduced free radicals and singlet oxygen species and the consequent high levels of cell viability may be the result of effective and efficient antioxidant and radical scavenging properties of silica hydride.     

Pyruvate in organ transplantation.

Pyruvate (PY) is a 3-carbon compound present in human tissues and physiologically used by cells as an energetic substrate in anaerobic conditions. In the last few years, we have successfully used PY to protect small bowel (SB), liver, and kidneys from ischemia/reperfusion injury in several experimental models. Although the mechanism of protection is not fully clarified, we have shown increased tissue levels of adenosine triphosphate (ATP) during ischemia. This suggests that providing supra-physiologic concentrations of PY during anaerobic glycolysis might enable the cells to remain viable during prolonged hypoxia. Furthermore, mechanisms such as direct inhibition of oxygen free radical formation, abrogation of neutrophilic infiltration and reduced up-regulation of adhesion molecules have also been documented in these studies. In light of these findings, we evaluated the efficacy of PY in organ preservation and transplantation. We demonstrated a protective effect on intestinal preservation injury and during acute rejection. Oral PY treatment induced immunologic changes in rejecting allograft, inhibiting perforin and granzyme-b expression and leukocytic infiltration. Protection was also documented on livers after prolonged hypothermic preservation using a PY based preservation solution. Additionally, isolated pancreatic islets were cultured in PY enriched media and maintained viable for up to 120 days followed by in vitro testing and transplantation revealing a well preserved function. All these findings suggest that PY is a potentially beneficial nutrient in patients undergoing organ transplantation and that future clinical application of PY in this field should be encouraged.     

Preoperative fasting induced protection against renal ischemia/reperfusion injury is independent of ghrelin in mice

One of the factors negatively influencing the outcome after kidney transplantation is ischemia-reperfusion (I/R) injury. Preoperative fasting is able to confer protection against I/R injury. We hypothesized that the protection imposed by preoperative fasting is mediated by increased levels of acylated ghrelin. Male C57BL/6 mice, 10 to 12 weeks old, were fasted for 1, 2, or 3 days, after which, acylated ghrelin levels were determined. Ad libitum fed mice were injected with acylated ghrelin or phosphate-buffered saline before renal I/R injury. Furthermore, mice were fasted for 3 days during which they were injected with a growth hormone secretagogue receptor antagonist, to block the effects of ghrelin, or a vehiculum. Bilateral renal I/R injury was induced by clamping the artery and vein of the left and right kidney simultaneously for 37 minutes. Kidney function was assessed by means of serum urea values determined at 24 and 48 hours after reperfusion. Fasting significantly increased acylated ghrelin serum levels. Ghrelin suppletion in ad libitum fed animals or ghrelin receptor blockade in fasted animals did not affect renal function after I/R injury. Our data suggest that the increased levels of acylated ghrelin induced by fasting do not mediate its protection against renal I/R injury.     

Possible molecular basis of cardioprotective effects of green tea

Clinical data suggest that people who use green tea have a lower cardiovascular risk. However, the exact mechanisms of these cardioprotective effects are unknown. We know that STAT1 plays a critical role in promoting apoptotic cell death and STAT3 may antagonise STAT1 and protect cardiac myocytes from ischaemia/reperfusion (I/R) injury. More recently it has been shown that specific molecules such as epigallocatechin-3-gallate (EGCG), which is present in green tea extract (GTE), have antioxidant properties. Considering that: (i) oxygen free radicals (OFR) are produced during myocardial I/R insult and (ii) OFR are responsible for reperfusion cardiac damage, we therefore investigated whether chronic administration per os of GTE reduced I/R damage in the Langendorff perfused isolated rat heart. In addition we evaluated myocardial content of STAT1 and STAT3 and degree of apoptosis. In Sprague-Dawley isolated hearts, GTE reduced the ischaemic mechanical insult, prolonged STAT3 activation/phosphorylation and reduced STAT1 activation with consequent less cell apoptosis. These results show that chronic treatment with GTE protects the heart from I/R injury. Activation of prosurvival STAT3 over the pro-apoptotic STAT1 could be one of the molecular mechanisms involved in green tea-mediated cardiopretection.     

蜂胶水提液对大鼠肠缺血再灌注后肝的保护作用

目的研究蜂胶水提液(WEP)在大鼠肠缺血/再灌注(I/R)过程中对肝组织的保护作用及其机制。方法 40只健康雄性Wistar大鼠随机分为假手术(Sham)、I/R和WEP(50、100、200 mg/kg)组。肠系膜上动脉阻断45 min、再灌注2 h建立肠I/R模型。采血检测转氨酶(ALT、AST)活性、肝组织髓过氧化酶(MPO)、超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量。常规制备病理切片,光镜下观察肝组织病理学改变。结果 (1)与sham组比较,I/R组血中转氨酶水平和肝MPO活性升高(P0.01),肝SOD活性降低而MDA含量增加(P0.01),肝组织明显淤血坏死。(2)与I/R组比较,WEP组血中转氨酶水平和肝MPO活性降低,WEP剂量依赖性地抑制肠I/R所致的肝组织SOD活性降低和MDA含量升高。肝组织淤血坏死减轻。结论蜂胶水提液可通过抗氧化反应、降低自由基生成,减轻大鼠肠I/R所致的肝损伤。     

Effect of anthocyanins on expression of matrix metalloproteinase-2 in naproxen-induced gastric ulcers

Non-steroidal anti-inflammatory drugs cause gastric ulceration through a number of mechanisms including inhibition of PG synthesis, generation of reactive oxygen species (ROS) and induction of apoptosis. Recently, matrix metalloproteinases (MMP) have been suggested to play a crucial role in these mechanisms. The present study investigated the protective effect of anthocyanins isolated from black rice bran (Heugjinjubyeo) against naproxen-induced gastric mucosal injury in rats. The oral administration of anthocyanins (5, 25 or 50?mg/kg body weight) showed significant protection against naproxen (80?mg/kg body weight)-induced gastric ulcer and inhibited lipid peroxidation in the gastric mucosa. In addition, pretreatment with anthocyanins resulted in a significant increase in the activities of radical-scavenging enzymes such as superoxide dismutase, catalase and glutathione peroxidase. Also biochemical and zymographic analyses suggested that the administration of anthocyanins gives a significant protection against naproxen-induced gastric antral ulcer through scavenging ROS and regulation of matrix metalloproteinase-2 (MMP-2) activity. The results of intracellular radical activation show that anthocyanins suppress the generation of intracellular ROS and attenuate the suppression of MMP-2 activity by naproxen. These results suggest that anthocyanins extracted from black rice may offer potential remedy of gastric antral ulceration.