Protective effect of hemoglobin—induced heme oxygenase—1 on injured lungs caused by limb ischemia—reperfusion in rats

OBJECTIVE: To determine the role of hemoglobin (HB) induced heme oxygenase-1 (HO-1) in injured lungs caused by limb ischemia-reperfusion (I/R) in rats. METHODS: A rat model of ischemia in the hind limbs was made by clamping the infrarenal aorta with a microvascular clip, and lung injury occurred after reperfusion. To induce the expression of HO-1 in the lungs, Hb was administrated intraperitoneally at 16 hours before reperfusion. Northern blotting and Western blotting were used to detect the expression of HO-1 in the lungs, and the carboxyhemoglobin (COHb) level in arterial blood was assayed. The effect of hemoglobin (Hb) on the injured lungs after limb I/R was determined by measuring the changes of lung histology, polymorphonuclear (PMN) count, malondialdehyde (MDA) content and wet-to-dry weight ratio (W/D). Zinc protoporphyrin (ZnPP), an inhibitor of HO, was used to determine whether HO-1 was induced by Hb after lung injury. RESULTS: Hb led to a significant increase in HO-1 mRNA and protein expression in the lungs, accompanied by the increase of COHb level in arterial blood. Compared with the sham controls, the lung PMN count, MDA content and W/D significantly increased at 4 hours after limb I/R, which reversed by the pretreatment with Hb at 16 hours before reperfusion. ZnPP blocked this protective role of Hb in the injured lungs. CONCLUSIONS: Hb can induce the lung HO-1 expression, which plays an important role in the defense against I/R induced lung injury in rats.     

Assessment of heme oxygenase-1 （HO-1） activity in the cavernous tissues of sildenafil citrate-treated rats

Aim： To assess heine oxygenase-1 （HO-1） activity in the cavemous tissue of sildenafil citrate-treated rats. Methods： One hundred and ninety-two Sprague-Dawley male rats, divided into four equal groups, were investigated. Group 1, the control group, received regular animal chow; group 2 received sildenafil citrate by intragastric tube; group 3 received sildenafil and HO inhibitor （zinc protoporphyrin, ZnPP）; and group 4 received sildenafil and nitric oxide synthase （NOS） inhibitor L-nitroarginine methyl ester （L-NAME）. Twelve rats from each group were killed after 0.5 h, 1 h, 2 h and 3 h of drug administration. Then HO-1 activity, cGMP levels and NOS enzymatic activity in the cavernous tissues were estimated. Results： In cavemous tissue, HO-1 activity, NOS enzymatic activity and cGMP concentration increased significantly in sildenafil-treated rats compared to other groups throughout the experiment. Rats receiving either HO or NOS inhibitors showed a significant decrease in these parameters. HO- 1 cavemous tissue activity and NOS enzymatic activity demonstrated a positive significant correlation with cGMP levels （r = 0.646, r = 0.612 respectively; P 〈 0.001）. Conclusion： The actions of PDE5 inhibitor sildenafil citrate in the cavernous tissue are partly mediated through the interdependent relationship between both HO-1 and NOS activities.     

Functional recovery of the spinal cord following ischemia and reperfusion injury

OBJECTIVE: To study the changes of excitatory amino acids (EAAs) and intracellular calcium ([Ca2+]i), and the protective effect of EAAs receptor antagonists in the tissues of rabbit lumbar spinal cord after 40-minues ischemia and 4-hours reperfusion. METHODS: Thirty healthy rabbits were divided into six groups: sham-operation, 40-minues ischemia, 4-hour reperfusion, ketamine and MgSO4 treatment, ketamine treatment, and saline treatment groups. The contents of EAAs (glutamate and aspartate) and [Ca2+]i were measured. RESULTS: The contents of glutamate and aspartate were decreased to 15.18 micromol/g+/-2.33 micromol/g and 9.99 micromol/g+/-0.69 micromol/g, respectively; 13.75 micromol/g+/-2.58 micromol/g and 6.49 micromol/g+/-1.39 micromol/g after reperfusion. In the ischemia group, the [Ca2+]i was elevated to 221.2 microg/g+/-4.27 microg/g, and elevated further to 298.3 microg/g+/-9.26 microg/g after reperfusion, being significantly higher than that of ischemia and control groups. Ketamine could obviously increase the level of glutamate and aspartate and decrease the level of [Ca2+]i during the ischemia and reperfusion injury. CONCLUSIONS: The excitotoxicity of EAAs and the overload of calcium induced by EAAs play a harmful role in ischemia and reperfusion injury. Ketamine has an effective inhibitory effect.     

nNOS expression of hippocampal neurons in aged rats after brain ischemia／reperfusion and its role in DND development

OBJECTIVE: To study the role of neuronal nitric oxide synthase (nNOS) in aged rats' hippocampal delayed neuronal death (DND) following brain ischemia. METHODS: Models of incomplete brain ischemia were induced by clipping common carotid artery. A total of 46 aged SD rats were divided into 8 groups: normal control group (Group A, n=5), sham-operation group (Group B, n=5), reperfusion 1, 6, 12, 24, 48, and 96 hours groups after brain ischemia for 30 minutes (Group C, D, E, F, G, and H, n=6/group). The expression of nNOS was examined by immunohistochemistry and neuronal ultrastructural changes were observed by the transmission electron microscopy (TEM) at different time points after reperfusion. RESULTS: Immunohistochemistry showed that nNOS expression in the hippocampal neurons was high in Group E, low expression in Group D, moderate expression in Group F and G. There was nearly no expression of nNOS in Group A, B, C, and H. Ultrastructure of hippocampal neurons was damaged more severely in reperfusion over 24 hours groups. CONCLUSIONS: Nitric oxide (NO) may be one of the important factors in inducing DND after ischemia/reperfusion.     

Pretreatment effect of adenosine on activation of NF—κB and level of TNF—α during myocardial ischemia and reperfusion in rats

Ithasbeenshownthatischemiaandreperfusion(I/R)increasecytokinelevelsincludingTNF α ,IL 1,IL 6 ,IL 8,IF γ ,andintercellularadhesionmolecule 1(ICAM 1)inthemyocardium .1TNF αandIL 6arethoughttobeimportantintheprogressionofmyocardialdysfunction .2 AdenosineinhibitsmyocardialTNF αproductionin postischenmicrat ,reduceshumanmyocardialinjuryafterI/R ,3anddecreasesLipopolysaccharide (LPS )inducedcardiacandmacrophageTNF a production .4 However ,themolecularmechanismsofadenosineinthedown …     

血红素氧合酶-1在临床肝移植中肝脏保护作用的研究

目的 研究移植肝脏血红素氧合酶(HO-1)表达水平与缺血再灌注损伤和移植术后肝脏功能的关系.方法 研究28例人类临床原位肝脏移植,根据供肝血红素氧合酶(HO-1)表达的平均值将供肝分为两组:移植前供肝HO-1高表达组和移植前供肝HO-1低表达组.比较两组移植术后血浆AST、ALT水平、胆汁中胆盐含量以及术前术后HO-1 mRNA和蛋白表达情况.结果 再灌注后移植术前HO-1低表达组的HO-1 mRNA表达显著增加,而高表达组HO-1 mRNA表达却有所下降.肝脏移植后,术前HO-1低表达组与高表达组相比,血浆转氨酶显著降低,胆汁中胆盐含量明显高于后者.结论 移植术前HO-1低表达组供肝在再灌注过程中能够进一步诱导HO-1表达,与高表达组供肝相比其所遭受的缺血再灌注损伤较轻,移植术后肝脏功能较好.移植过程中HO-1表达的增强要比移植前HO-1高表达更具有细胞保护作用.免疫荧光染色证实枯否细胞是人类肝脏表达HO-1的主要部位.     

血红素氧合酶-1对大鼠肾缺血再灌注损伤的保护作用

目的　探讨钴卟啉 (CoPP)诱导的血红素氧合酶 (HO) 1高表达对大鼠肾缺血再灌注损伤 (IRI)的保护作用。方法　建立大鼠肾缺血再灌注损伤模型 ,随机将动物分为假手术组 ,对照组和实验组。动态检测血尿素氮 (BUN)、肌酐 (Cr)、超氧化物岐化酶 (SOD)、丙二醛 (MDA)的含量以及进行肾组织光镜形态学观察和酶联免疫吸附试验 (ELISA)和Westernblot分析HO 1。结果　对照组BUN、Cr升高 ,SOD下降 ,MDA升高 ,HO 1中度提高 (14 4.5± 13 .6) ,肾组织结构紊乱。实验组除HO 1含量大幅提高外 (62 9.4± 78.9) ,尚能显著逆转上述改变 ,两组间差异具有统计学意义 (P <0 .0 5 )。结论　CoPP预处理诱导HO 1在肾缺血之前高表达可通过清除氧自由基 (OFRs)而减轻大鼠肾IRI。     

诱导HO-1改善氧化应激状态减轻老年供肝缺血-再灌注损伤

目的观察诱导血红素氧合酶-1(HO-1) 生成能否减轻老年供肝移植后缺血-再灌注损伤.方法取老年(16个月龄)SD大鼠5只和成年(3个月龄)大鼠5只,分别测定其肝脏组织中超氧化物歧化酶(SOD)和过氧化氢酶(CAT)的活性及维生素E(Vit E)、维生素C(Vit C)和丙二醛(MDA)含量; 另取老年SD大鼠60只作为供体,随机均分为血晶素(Hemin)组和对照组,分别于取肝前24 h腹腔注射Hemin或生理盐水,然后将其肝脏移植给同种大鼠,同时观察再灌注后肝脏组织学变化和细胞凋亡.结果老年大鼠肝脏组织中SOD活性明显低于成年大鼠,Vit C含量亦少(P＜0.05),而MDA明显增高(P＜0.05).用Hemin预处理的老年SD大鼠供肝在切取前,SOD活性增加,Vit E、Vit C含量增加,MDA含量降低(P＜0.05); 肝移植后血清ALT明显降低,肝组织HO-1活性明显增高,肝脏组织学检查示再灌注后凋亡细胞明显减少(P＜0.05).结论老年SD大鼠肝脏存在氧化应激和脂质过氧化状态,HO-1可通过改善这种状态而减轻其缺血-再灌注损伤.     

血红素氧合酶-1在HO-1/Luc小鼠原位肝脏移植模型中的表达

目的 应用活体生物萤光成像技术(BLT)无创定量检测血红素氧合酶-1(HO-1)在活体动物肝脏移植模型中的时空表达.方法 建立小鼠原位肝脏移植模型(HO-1/Luc转基因小鼠8只,wildtype小鼠40只),使用活体生物萤光成像技术连续检测HO-1在移植术后HO-1/Luc转基因小鼠中的转录.应用逆转录-聚合酶链反应(RT-PCR)检测HO-1 mRNA水平,免疫组织化学方法 (IHC)行HO-1的表达定位.结果 移植肝脏发出的萤光信号最早于移植后1 h被检测到(P<0.05),随后信号不断增强在6 h达到峰值.与移植术前比较,除0、48 h外信号差异均有统计学意义(P<0.05).移植后48 h信号衰减至基础水平.与移植术前比较,RT-PCR方法 测得HO-1 mRNA于0～9 h均显著升高(P<0.05),其中于3 h达到峰值,12 h降至基础水平.IHC证实肝脏细胞是移植后HO-1表达上调的主要部位.结论 活体生物萤光成像技术可实时定量检测肝脏移植后HO-1的表达.     

梗阻性黄疸大鼠肺血红素氧化酶-1 mRNA表达及一氧化碳含量的变化

目的探讨梗阻性黄疸时肺血红素氧化酶(HO)1mRNA表达及一氧化碳(CO)含量变化的意义。方法健康雄性Wistar大鼠48只,随机等分成4组假手术对照组(CG)、梗阻性黄疸7d组、梗阻性黄疸14d组和梗阻性黄疸21d组。应用原位杂交技术行HO1mRNA表达检测,采用双波长分光光度计法测定大鼠血浆及肺组织匀浆中CO含量。结果7d组大鼠肺泡上皮细胞HO1mRNA表达呈中度阳性,14d组支气管黏膜上皮细胞、血管内皮细胞中HO1mRNA高表达,而21d组其表达进一步增强;14d和21d组血浆中CO含量均较CG组增高(P<0.05,P<0.01),梗阻性黄疸各组肺组织匀浆中CO含量均较CG组明显升高(P<0.01);7、14及21d组肺组织匀浆中CO含量的升高分别与同时间组肺HO1mRNA表达变化呈显著正相关。结论梗阻性黄疸时肺HO1mRNA的高表达及CO产生增多,有助于扩张肺血管并改善肺微循环,从而减轻梗阻性黄疸时肺损害的程度。     

细胞穿透肽PEP-1导入血红素加氧酶-1蛋白对大鼠肾缺血再灌注损伤的影响

目的 评价细胞穿透肽PEP-1导入血红素加氧酶-1(HO-1)蛋白对大鼠肾缺血再灌注损伤的影响.方法 健康雄性SD大鼠18只,周龄7～9周,体重210 ～ 260 g,采用随机数字表法,将其随机分为3组(n=6):假手术组(S组)、肾缺血再灌注组(I/R组)和融合蛋白PEP-1/HO-1+肾缺血再灌注组(HO组).采用夹闭双侧肾动脉45 min恢复灌注的方法制备大鼠肾缺血再灌注损伤模型.HO组于夹闭双侧肾动脉前30 min时静脉注射融合蛋白PEP-1/HO-1.于再灌注6h时取右侧颈总动脉血样,测定血清BUN和Cr浓度;取肾组织检测MDA含量和SOD活性;采用免疫组化法检测肾组织HO-1的表达.结果 与S组比较,I/R组和HO组肾组织MDA含量、血清BUN和Cr浓度升高,肾组织SOD活性降低,HO-1蛋白表达上调(P＜0.05);与I/R组比较,HO组肾组织MDA含量、血清BUN和Cr浓度降低,肾组织SOD活性升高,HO-1蛋白表达上调(P＜0.05).结论 细胞穿透肽PEP-1将HO-1蛋白成功导入肾组织,导入的HO-1蛋白通过抑制脂质过氧化反应减轻肾缺血再灌注损伤.     

胱硫醚β-合酶/硫化氢和血红素氧合酶-1/一氧化碳体系在大鼠脑缺血再灌注损伤中的作用

目的 研究胱硫醚β-合酶（CBS）／硫化氢（H2S）体系和血红素氧合酶-1（HO-1）／一氧化碳（CO）体系在大鼠脑缺血再灌注损伤中的作用。方法 30只Wistar大鼠随机分为5组（n=6）：对照组（C组）、脑缺血再灌注组（I／R组）、脑缺血再灌注＋锌原卟啉（HO-1抑制剂）组（I／R＋Z组）、脑缺血再灌注＋羟氨（CBS抑制剂）组（I／R＋H组）、脑缺血再灌注＋锌原卟啉＋羟氨组（I／R＋Z＋H组）。采用四血管阻断法建立全脑缺血再灌注损伤模型，I／R＋Z组、I／R＋H组和I／R＋Z＋H组夹闭两侧颈总动脉前30min分别腹腔注射锌原卟啉45／zmol／kg、羟氨5mmol／L、羟氨5mmol／L＋锌原卟啉45／maol／kg1ml，C、I／R组给予等量生理盐水。再灌注6h时处死大鼠，取海马，测定海马组织H2S、CO、还原型谷胱甘肽（GSH）、丙二醛（MDA）、超氧化物歧化酶（SOD）水平及CBSmRNA和HO-1mRNA的表达；电镜下观察海马线粒体变性情况。结果 与C组比较，I／R组海马组织CO、H2S、CBSmRNA和HO-1mRNA、MDA水平及线粒体变性率均升高，海马组织SOD、GSH水平降低（P〈0．01）；与I／R组比较，I／R＋Z组海马组织CO、HO-1mRNA水平降低，海马组织H2S、CBSmRNA、GSH、MDA水平升高，I／R＋H组海马组织CO、HO-1mRNA、MDA水平升高，H2S、CBSmRNA、GSH水平降低；I／R＋Z＋H组海马组织CO、RS、HO-1mRNA和CBSmRNA、SOD、GSH水平降低，线粒体变性率升高（P〈0．05）。结论 CBS／H1S体系和HO-1／CO体系可拮抗大鼠脑缺血再灌注损伤，其作用可相互代偿。     

钴原卟啉诱导血红素氧合酶-1高表达减轻大鼠肾脏缺血再灌注损伤

目的 探讨钴原卟啉(CoPP)诱导血红素氧合酶-1(HO-1)高表达对大鼠肾脏缺血再灌注损伤(IRI)的影响及其机理.方法 以Wistar大鼠为实验对象,CoPP组分别于左肾血流阻断前48 h和24 h腹腔注射CoPP 2.5 mg/kg,然后阻断左肾血流47 min,恢复左肾血流的同时切取大鼠右肾,采用免疫组织化学染色和免疫印迹法检测其HO-1的表达.在再灌注24 h后,处死大鼠,取其下腔静脉血和左肾,测定血肌酐(Cr)和尿素氮(BUN)浓度,观察肾组织学变化,检测肾组织中HO-1的表达.IRI组除不用CoPP处理外,其余同CoPP组.CoPP组和IRI组另有部分大鼠的血流阻断时间延长至80 min,恢复血流后不处死,观察14 d,记录其存活情况.结果 IRI组血清Cr及BUN分别为(134.37±24.26)μmol/L和(30.10±3.09)mmol/L,明显高于CoPP组的(48.92±12.92)μmol/L和(13.99±5.00)mmol/L(P＜0.05).IRI组肾小管细胞大片坏死,管型形成,与之相比,CoPP组肾小管坏死范围稍小,但肾小管病变范围仍较广泛,肾小管上皮细胞多处于水变性阶段,"缺血样"肾小球减少,管型形成较少.缺血前及再灌注24 h后,CoPP组的肾组织中HO-1均为高表达,主要位于肾间质的毛细血管处,IRI组再灌注24 h后也见肾组织中HO-1为高表达.术后14 d内,IRI组的6只大鼠中有4只死亡,而CoPP组的5只大鼠全部存活,两组大鼠存活率的差异有统计学意义(P＜0.05).结论 缺血前使用CoPP可减轻大鼠肾脏缺血再灌注损伤,该保护作用可能是通过CoPP诱导肾脏高表达HO-1来实现的.     

大鼠血红素加氧酶-1基因转染对心肌缺血再灌注损伤大鼠炎性因子的影响

目的探讨重组腺相关病毒（rAAV）介导大鼠血红素加氧酶-1（HO-1）基因转染对心肌缺血再灌注损伤大鼠炎性因子的影响。方法雄性SD大鼠93只，体重225．275g，随机分为4组：假手术组（SH组，n=12）、生理盐水组（NS组，n=27）、重组腺相关病毒．荧光蛋白组（rAAv-EGFP组。n=27）及重组腺相关病毒．血红素加氧酶-1组（rAAV-rHO-1组，n=27）。NS组、rAAV-EGFP组和rAAV-rHO-1组分别于左心室前后壁共取4点注入600μl生理盐水、rAAV-EGFP或rAAV-HO-1病毒液。在基因转染后3个月，通过RT-PCR和Westernblot法检测HO-1mRNA和蛋白的表达，荧光显微镜下观察荧光蛋白的表达。采用结扎左冠状动脉前降支30min、再灌注120min的方法建立大鼠心肌缺血再灌注模型，再灌注120min后，处死大鼠，测定心肌梗死面积及血清TNF-α、IL-6水平，电镜下观察心肌细胞的超微结构。结果rAAV-rHO-1组HO-1表达明显高于NS组和rAAV-EGFP组（P〈0．01），仅rAAV-EGFP组心肌观察到荧光蛋白的表达；与SH组比较，NS组、rAAV-EGFP组和rAAV-rHO-1组心肌梗死面积增加，血清TNF-α、IL-6水平明显升高（P〈0．05），心肌结构紊乱；与NS组和rAAV-EGFP组比较，rAAV-rHO-1组心肌梗死面积减少（P〈0．01），血清TNF-α、IL-6水平明显降低（P〈0．05），心肌结构破坏程度较轻。结论重组腺相关病毒介导大鼠血红素加氧酶-1基因转染大鼠心肌细胞后，降低炎性因子的产生，从而减轻心肌缺血再灌注损伤。     

血红素氧合酶1基因转移对大鼠肾缺血再灌注损伤的防护作用

目的探讨血红素氧合酶1(HO-1)基因转移对大鼠自体移植肾缺血再灌注损伤的保护作用。方法构建HO-1腺病毒表达载体,经肾动脉灌注转染26只大鼠(实验组)移植肾,4℃保存24h后行自体移植,移植后5d切除对侧肾脏;以25只大鼠为对照。于移植后3h、3d,应用逆转录聚合酶链反应(RT-PCR)及免疫组织化学方法检测移植肾HO-1基因及蛋白的表达;应用酶联免疫吸附试验(ELISA)法测定肾组织匀浆中HO-1蛋白的含量(以吸光度值表示)。结果移植后3h及3d,实验组移植肾HO-1mRNA的表达强度分别为0·65±0·11及0·86±0·17,而对照组分别为0·09±0·01及0·15±0·02,两组相比差异具有统计学意义(t=14·38,11·73,P均<0·05);实验组移植肾HO-1蛋白含量分别为(297±61)及(468±51)ng/g,而对照组分别为(98±30)及(155±31)ng/g,两组相比差异具有统计学意义(t=8·27,14·83,P均<0·05)。与对照组相比实验组移植肾病理改变明显减轻(P<0·05),血肌酐水平明显降低(t=8·41,P<0·05)。结论腺病毒载体可成功介导HO-1基因对大鼠肾脏的转移,对自体移植肾缺血再灌注损伤具有保护作用。     

HO-1/CO系统在缺血/再灌注中的保护机制

缺血/再灌注(ischemia/reperfusion,I/R)损伤是心肌梗死等许多疾病的病理生理基础,也是手术、创伤、休克以及器官移植导致器官功能和结构损伤的原因之一.在已知的I/R损伤的众多病理机制中已经明确氧化应激产生的活性氧自由基和炎症反应具有重要的作用.血色素氧合酶-1(heme oxygenase-1,HO-1)能催化血色素降解生成胆绿素、一氧化碳(carbon monoxide,CO),并释放Fe2+离子.近年来的研究已经证明HO-1及其催化产物CO具有抗氧化应激和抗炎作用,在正规损伤中能够发挥对组织器官的保护作用.现就I/R损伤中HO-1/CO系统的保护作用进行综合阐述.     

转染血红素氧合酶-1基因减轻大鼠脂肪肝移植后的缺血再灌注损伤

目的 探讨转染血红素氧合酶-1(HO-1)基因对大鼠脂肪肝移植后缺血再灌注损伤的影响.方法 利用分子生物学方法构建携带有HO-1基因的重组腺病毒(Ad5-HO-1),于供肝切取前48 h经阴茎背静脉将Ad5-HO-1注入供者体内,供肝置于4℃HTK液保存2 h,然后移植.对照组接受正常肝移植;轻度对照组接受轻度脂肪肝移植;轻度实验组接受注射Ad5～HO-1的轻度脂肪肝移植;重度对照组接受重度脂肪肝移植;重度实验组接受注射Ad5-HO-1的重度脂肪肝移植.术后观察各组大鼠的存活率及肝功能;观察移植肝组织的病理变化;测定移植肝组织中HO-1的活性以及HO-1、Bcl-2、锌指蛋白A20、凋亡蛋白酶-3(Caspase-3)的表达.结果 与重度对照组相比较,重度实验组的丙氨酸转氨酶水平显著下降(P＜0.05).轻度实验组和重度实验组的HO-1活性分别高于各自的对照组(P＜0.05).重度实验组移植肝组织中HO-1、Bcl-2及锌指蛋白A20的表达水平明显高于重度对照组(P＜0.05),而Caspase-3的表达是降低的(P＜0.05).重度实验组的1、7、21 d存活率分别为66.7%(4/6)、50%(3/6)和50%(3/6),而重度对照组的1、7、21 d存活率分别为33.3%(2/6)、16.7%(1/6)和16.7%(1/6),二者比较,差异有统计学意义(P＜0.05).结论 转染血HO-1基因可减轻大鼠脂肪肝移植后的缺血再灌注损伤.     

缺血后处理对大鼠缺血再灌注损伤肝脏血红素加氧酶-1表达的影响

灌注损伤,其机制可能与增加HO-1的表达和增强移植肝脏抗氧化能力有关.