乌司他丁对大鼠原位肝脏移植供肝的保护作用

目的：探讨乌司他丁对大鼠原位肝脏移植供肝的保护作用及机制。 方法：分别用单纯UW液（模型组）或含乌司他丁（乌司他丁组）、HO-1诱导剂CoPP（CoPP组）、HO-1抑制剂ZnPP（ZnPP组）的UW液灌注切取的供体大鼠肝脏并保留灌注液1 h后,原位移植受体大鼠。移植后24 h取移植肝脏与受体大鼠血标本,行肝脏病理学检查及评分;分别用real-time PCR和Western bolt法检测肝组织HO-1 mRNA与蛋白的表达;用Elisa法检测大鼠血清中IL-2和IL-10的含量。 结果：与模型组比较,乌司他丁组与CoPP组供肝的损伤明显减轻、Suzuki评分降低,而ZnPP组损伤加重、Suzuki评分升高（均P<0.05）;乌司他丁组与CoPP组HO-1 mRNA与蛋白的表达明显上调,而ZnPP组明显下调（均P<0.05）;乌司他丁组与CoPP组大鼠血清中IL-2水平明显降低、IL-10水平明显升高,而ZnPP组IL-2水平明显升高、IL-10水平明显降低（均P<0.05）。 结论：乌司他丁可能通过上调移植大鼠肝脏的HO-1水平,减轻再灌注损伤、抑制排斥反应而发挥保护作用。

     

血红素加氧酶-1诱导对鼠肝缺血再灌注损伤的保护作用

目的研究血红素加氧酶-1(heme oxygenase-1,HO-1)在鼠肝缺血再灌注损伤肝组织中的表达及其作用。方法建立小鼠部分肝脏热缺血再灌注损伤模型,36只清洁级Balb/C小鼠随机分为3组: 假手术组(S组)、缺血/再灌注损伤组(I/R组)、HO-1诱导剂氯化高铁血红素(hemin)预处理组(HM组)。免疫组化半定量分析肝组织HO-1蛋白的表达,检测血清AST和ALT,肝组织丙二醛(MDA)含量及超氧化物歧化酶(SOD)活性,并观察肝组织的病理变化。结果与S组比较,I/R组HO-1蛋白表达显著增强,hemin预处理后,HO-1蛋白表达较I/R组增高(P<0．01)。I/R组AST,ALT活性和MDA的含量显著高于S组,而HM组均显著低于I/R组(P<0．01);I/R组SOD活性下降,而HM组显著高于I/R组(P<0．01)。HM组病理损伤程度明显轻于I/R组。结论 HO-1在鼠肝缺血再灌注损伤肝组织中表达上调,对肝脏具有保护效应。     

白藜芦醇对肝脏缺血再灌注损伤的保护作用

摘要：探讨白藜芦醇对肝脏缺血再灌注损伤的防护作用。将雄性SD大鼠随机分为空白对照组、缺血再灌注组（I/R组）、I/R加生理盐水处理组和I/R加白藜芦醇处理组。观察肝脏缺血40 min再灌注1，3，6，12h后血清谷丙转氨酶（ALT）、谷草转氨酶（AST）及肝组织丙二醛（MDA）含量的变化以及肝组织病理学改变。结果示肝脏I/R后血清ALT，AST及肝组织MDA含量均显著升高，肝脏缺血再灌注前用白藜芦醇15 mg/kg者，血清ALT，AST及肝组织MDA含量均明显降低，且肝组织病理学损害明显减轻。结果表明白藜芦醇对肝脏I/R损伤具有保护作用     

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.     

瑞芬太尼对肝硬化大鼠肝脏缺血再灌注损伤的影响

目的 探讨瑞芬太尼对肝硬化大鼠肝脏缺血再灌注损伤的影响.方法 成年健康雄性SD大鼠30只,体重260～300 g,采用随机数字表法,将其随机分为3组(n=10):肝硬化组(C组)、肝硬化+肝缺血再灌注组(I/R组)和瑞芬太尼组(R组).C组、I/R组和R组采用四因素综合法制备大鼠肝硬化模型,I/R组和R组在肝硬化模型制备成功后1周制备大鼠70％肝脏缺血再灌注模型,R组于缺血前10 min开始静脉输注瑞芬太尼1μg·kg-1·min-至再灌注结束.于再灌注4h时取静脉血样和肝组织,测定血清ALT和AST活性、肝细胞Bcl-2和Bax表达及肝细胞凋亡情况,计算细胞凋亡指数,光镜下观察肝组织病理学结果.结果 与C组比较,I/R组血清ALT和AST的活性升高,肝细胞Bcl-2表达下调,Bax表达上调,细胞凋亡指数升高(P＜0.05);与I/R组比较,R组血清ALT和AST的活性降低,肝细胞Bcl-2表达上调,Bax表达下调,细胞凋亡指数降低(P＜0.05).R组肝组织病理学损伤轻于I/R组.结论 瑞芬太尼可减轻肝硬化大鼠肝脏缺血再灌注损伤,其机制与平衡肝细胞Bcl-2与Bax表达而抑制肝细胞凋亡有关.     

血红素加氧酶-1在治疗性高碳酸血症减轻大鼠肝缺血-再灌注损伤中的作用

目的探究血红素加氧酶-1(HO-1)在治疗性高碳酸血症减轻大鼠肝缺血-再灌注损伤中的作用。方法健康成年SD大鼠60只,随机均分为四组:假手术组(C组)、肝缺血-再灌注损伤组(IR组)、治疗性高碳酸血症处理组(A组)、治疗性高碳酸血症处理+锌原卟啉(ZnPP)预处理组(B组)。通过夹闭大鼠肝门静脉,肝动脉及胆管建立部分肝脏缺血-再灌注损伤模型,实验共缺血1h,再灌注6h。C组和IR组:实验全程机械通气吸入50%O2-50%N2;A组和B组:缺血即刻至再灌注结束期间吸入外源性50%O2-45%N2-5%CO2,C组、IR组、A组于实验前24h腹腔注射生理盐水5ml/kg,B组注射ZnPP 5mg/kg。于机械通气前(基础值)、缺血前即刻、再灌注即刻、再灌注后1、2、3、4、5、6h检测动脉血PaCO2;再灌注6h后取血清检测ALT、AST和TNF-α,并取肝组织HE染色观察病理学改变,TUNEL法检测细胞凋亡水平,Western blot法检测HO-1的相对量表达。结果与C组和IR组比较,A组和B组动脉血PaCO2水平明显升高(P0.05)。与C组比较,IR组肝组织损伤严重,IR组、A组和B组血清ALT、AST和TNF-α含量、凋亡指数和A组HO-1相对表达量明显升高(P0.05)。与IR组比较,A组肝组织损伤减轻,A组和B组血清ALT、AST、TNF-α含量、凋亡指数和B组的HO-1相对表达量明显降低(P0.05),而A组HO-1相对表达量明显升高(P0.05)。与A组比较,B组肝组织损伤加重,血清ALT、AST、TNF-α含量、凋亡指数明显升高(P0.05),HO-1相对表达量明显下降(P0.05)。结论治疗性高碳酸血症通过上调HO-1有效减轻肝缺血-再灌注损伤。     

YAP在肝脏缺血-再灌注损伤中的作用及其机制

目的探究Yes相关蛋白(YAP)在小鼠肝脏缺血-再灌注损伤(IRI)中的作用及机制。方法雄性C57BL/6小鼠40只,按随机数字表法分为假手术组(Sham组)、溶血磷脂酸(LPA)+Sham组、IRI组、 LPA+IRI组,每组10只。缺血-再灌注6 h后,收集肝组织和血清标本。检测血清丙氨酸转氨酶(ALT)和天冬氨酸转氨酶(AST)的水平,苏木素-伊红(HE)染色、免疫组织化学(免疫组化)染色检测肝组织病理学改变和巨噬细胞浸润情况,蛋白印迹法分析肝组织YAP的蛋白表达水平,逆转录聚合酶链反应(RT-PCR)法评估炎症因子肿瘤坏死因子(TNF)-α、诱生型一氧化氮合酶(iNOS)、白细胞介素(IL)-1和IL-6的信使核糖核酸(mRNA)表达水平。结果蛋白印迹结果显示,LPA+IRI组YAP的蛋白表达水平较IRI组明显升高。与Sham组相比,IRI组ALT和AST显著增高(均为P0.05);LPA+IRI组较IRI组血清ALT和AST显著降低(均为P0.05)。HE染色显示,Sham组和LPA+Sham组肝细胞形态正常;LPA+IRI组和IRI组出现肝脏淤血、肝细胞肿胀和肝小叶结构异常等病理改变;LPA+IRI组相较于IRI组病理改变程度减轻。RT-PCR提示,LPA+IRI组中炎症因子TNF-α、iNOS、IL-1和IL-6的mRNA表达水平较IRI组降低(均为P0.05)。免疫组化显示,LPA部分抑制了IRI后缺血组织巨噬细胞浸润。结论 YAP能明显缓解肝脏IRI,其作用机制与调控巨噬细胞募集和活化相关。     

瑞香素激活Keap1/NRF2通路减轻小鼠肝脏缺血再灌注损伤的实验研究

目的:探讨瑞香素对小鼠肝脏缺血再灌注损伤(IRI)的保护作用及机制。方法:构建小鼠70%肝脏IRI模型,将小鼠随机分为假手术组(Sham组)、瑞香素组(Dap组)、缺血再灌注组(IRI组)、缺血再灌注+瑞香素组(IRI+Dap组),每组8只。Sham组和IRI组小鼠腹腔注射0.9%氯化钠溶液,Dap组和IRI+Dap组小鼠肝脏缺血前1 h腹腔注射Dap(1.5 mg/kg)。IRI术后12 h处死小鼠收集标本,检测血清转氨酶及炎症因子的表达水平,取肝组织行苏木紫-伊红(HE)染色观察肝组织病理损伤,通过免疫荧光检测肝组织炎症因子的表达,通过ELISA检测肝组织氧化应激相关因子表达,通过蛋白印迹实验检测肝组织NRF2/HO-1通路相关蛋白的表达。结果:和IRI组小鼠相比,IRI+Dap组小鼠肝脏IRI 12 h后,血清中ALT、AST、TNFα、CCL2的表达显著降低,肝组织坏死面积显著减小,肝组织中CD11b、Ly6g阳性炎症细胞浸润属相显著减少,肝组织中MDA水平显著降低、SOD、GSH水平显著升高,同时肝组织中Keap1表达显著降低、HO-1、p-NRF2表达显著升高。结论:瑞香素能够显著抑制小鼠肝脏IRI后的炎症和氧化应激。瑞香素对肝脏IRI的保护作用可能是通过激活Keap1-NRF2通路实现。     

白术多糖对缺血再灌注损伤大鼠肝脏的保护作用

目的：探讨白术多糖对大鼠肝脏缺血再灌注（I/R）损伤的保护作用。
方法：成年雄性SD大鼠随机分成3组：假手术组,I/R组,白术多糖预处理缺血再灌注组（PC组）,分别于成模后1,6,24 h 3个时段分别检测3组大鼠血清谷丙转氨酶（ALT）和谷草转氨酶（AST）水平;检测肝组织中ICAM-1 mRNA含量及IL-1的表达。
结果：PC组及I/R组ALT,AST水平以及ICAM-1 mRNA含量和IL-1表达均高于假手术组（P＜0.05）,但PC组上述4个指标均较I/R组显著降低,差异有统计学意义（P＜0.05）。
结论：白术多糖可能通过降低ICAM-1的含量而减少炎症因子IL-1的生成,从而对肝脏I/R损伤起保护作用。     

N-乙酰半胱氨酸对大鼠肝缺血-再灌注损伤的保护作用及机制

目的探讨N-乙酰半胱氨酸(NAC)对肝缺血-再灌注损伤的保护作用及机制。方法60只Wistar大鼠随机分为3组:假手术组(P组),只开腹不阻断肝血流,I/R组和I/R-NAC组均阻断大鼠肝70%的血流,45min后恢复再灌注,其中I/R-NAC组再灌注前5min经尾静脉注射NAC300mg/kg。在再灌注后1、3、6、24h时,采取血液及肝组织,分别检测血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、脂多糖(LPS)、Toll样受体4(TLR4)mRNA及其蛋白的表达。结果I/R组和I/R-NAC组ALT、AST及LPS的含量均在6h达高峰,但组内在各时间点比较,ALT、AST及LPS含量的差异并无统计学意义(P>0.05);I/R组同一时间点的ALT、AST及LPS含量均高于I/R-NAC组(P<0.05)。I/R组肝组织TLR4mRNA的表达从再灌注3h起明显增强(P<0.01),并维持高表达,而I/R-NAC组TLR4mRNA的表达在各时间点无显著变化(P>0.05)。I/R组和I/R-NAC组TLR4蛋白表达在再灌注1、3h时类似于P组,但在6、24h时显著增强。结论TLR4参与了肝缺血-再灌注损伤的病理过程,NAC可通过抑制TLR4mRNA表达而减弱肠源性内毒素血症对肝脏的损伤。     

Heme oxygenase-1 overexpression protects rat hearts from cold ischemia/reperfusion injury via an antiapoptotic pathway

BACKGROUND: Ischemia/reperfusion (I/R) injury is one of the most important causes of the early graft loss. We have shown that overexpression of heme oxygenase-1 (HO-1), an inducible heat shock protein 32, protects rat livers against I/R injury. We report on the cytoprotective effects of HO-1 in a rat cardiac I/R injury model, using cobalt protoporphyrin (CoPP) as HO-1 inducer and zinc protoporphyrin (ZnPP) as HO-1 inhibitor. METHODS: Three groups of Lewis rats were studied: group 1 control donors received phosphate-buffered saline 48 hr before the harvest; group 2 donors were pretreated with CoPP at -48 hr; and in group 3, donors received CoPP at -48 hr and ZnPP was given to recipients at reperfusion. Hearts were harvested, stored in University of Wisconsin solution (4 degrees C) for 24 hr, and then transplanted to syngeneic (Lewis) rats. RESULTS: Sixty percent of control grafts ceased their function in <15 min. In contrast, 80% of CoPP-pretreated grafts survived 14 days. All grafts stopped functioning within 24 hr after CoPP + ZnPP therapy. Cardiac HO-1 enzymatic activity and protein expression correlated with beneficial effects of CoPP and deleterious effects of adjunctive ZnPP treatment. Markedly less apoptotic (TUNEL+) myocyte/endothelial cells could be detected in CoPP cardiac grafts, as compared with controls. The expression of antiapoptotic (Bcl-2/Bag-1) proteins was up-regulated in the CoPP group. CONCLUSION: HO-1 overexpression provides potent protection against cold I/R injury in a stringent rat cardiac model. This effect depends, at least in part, on HO-1-mediated up-regulation of a host antiapoptotic mechanism, especially in the early postreperfusion period.     

血红素氧合酶-1减轻大鼠移植肝缺血再灌注损伤的作用及机制

目的 探讨血红素氧合酶-1(HO-1)减轻大鼠移植肝缺血再灌注损伤的作用及其机制.方法 选择近交系雄性SD大鼠作为肝移植的供、受者;采用单纯随机方法将48只SD大鼠随机分为对照组、抑制组和诱导组(每组供、受者各8只).对照组:供肝不用任何药物处理;抑制组:在获取供肝前24 h,经供者腹腔注射HO-1抑制剂锌原卟啉20 mg/kg进行预处理;诱导组:在获取供肝前24 h,经供者腹腔注射HO-1诱导剂钴原卟啉5 mg/kg进行预处理.获取供肝后,在4℃UW液中冷保存24 h.肝移植前检测供肝HO-1的表达水平;肝移植后6 h采血并获取移植肝标本,分离培养枯否细胞;检测受者的肝功能;检测枯否细胞培养上清中肿瘤坏死因子α(TNF-α)和白细胞介素6(IL-6)的含量;观察移植肝组织病理学表现以及枯否细胞CD14 mRNA的表达水平和蛋白含量测定.结果 移植前诱导组供肝HO-1的表达水平明显增高.移植后诱导组血清丙氨酸转氨酶(ALT)和天冬氨酸转氨酶(AST)含量明显降低;移植肝组织病理学损伤减轻;枯否细胞培养上清中TNF-α和IL-6含量减少;而且枯否细胞上的CD14 mRNA表达水平和蛋白含量也明显低于抑制组.结论 诱导供肝HO-1表达上调可能抑制了枯否细胞的激活,从而减轻大鼠移植肝缺血再灌注损伤.     

Transient limb ischemia induces remote preconditioning in liver among rats: the protective role of heme oxygenase-1

BACKGROUND: We have reported the protective role of heme oxygenase-1 (HO-1) in the mechanism of hypoxic preconditioning. We wish to investigate the role of HO-1 in remote preconditioning (RP) against hepatic ischemia/reperfusion (I/R) injury in rats. METHODS: The remote preconditioning was produced by four cycles of 10-min ischemia-reperfusion of the hind limb of rats. Partial hepatic ischemia was produced in the left lobes for 45 min followed by 240 min of reperfusion. Zinc-protoporphyrin IX (ZnPP), a specific inhibitor of HO enzymatic activity, was intra-peritoneally injected 1 hr before the ischemia-reperfusion injury in separate groups of RP rats. Serum alanine transaminase (ALT) levels, expression of hepatic HO-1 protein and mRNA, immunohistochemical staining and HO enzymatic activity were measured. RESULTS: HO-1 was induced in the livers of rats 4 hr after the RP stimuli, and the overexpression persisted for 24 hr. Immunohistochemical staining demonstrated induction of HO-1 in the hepatocytes. The peripheral lymphocytes did not express HO-1 after RP. RP diminished the elevation of serum ALT levels 4 hr after I/R injury (283.7+/-167.4 U L) when compared with controls (1297.7+/-729.3 U L) and RP+ ZnPP pretreated groups (1429.9+/-750.9 U L). The heme oxygenase activity in treated rats also correlated these results (286.8+/-34.3 pmol mg protein hr for the RP group, 156.3+/-27.5 pmol mg protein hr for the RP+ ZnPP pretreated group, and 170.6+/-19.4 pmol mg protein hr for the control group, 144.8+/-7.8 pmol mg protein hr for the control+ ZnPP pretreated group). CONCLUSION: Our results indicated that the induction of HO-1 in remote preconditioning played a protective role against hepatic I/R injury.     

锌原卟啉对种植性乳腺癌细胞凋亡的影响

目的探讨锌原卟啉（ZnPP）对种植性乳腺癌细胞凋亡及信号传导和转录因子-3（STAT-3）的影响。方法应用种植性乳腺癌模型，结合ZnPP、钴原卟啉（CoPP）处理，分别用逆转录．聚合酶链反应（RT-PCR）检测乳腺癌组织中的血红素氧合酶-1（HO-1）mRNA并HO-1酶活性，免疫组织化学、Western blot蛋白印迹杂交检测癌组织中HO-1、CAS-3、bel-XL、STAT-3蛋白表达。TUNEL法评价肿瘤细胞凋亡。结果ZnPP组肿瘤平均直径明显低于其余各组（t=3．6324，P〈0．01）；CoPP组最大（t=3．5546，P〈0．01）。ZnPP组肿瘤组织内的HO-1 mRNA、HO-1蛋白及HO-1酶活性均低于其余各组，而CoPP组高于其余各组。ZnPP组STAT-3及bel-XL蛋白表达低于CoPP组（t=2．4216，P〈0．05）（t=4．3706，P〈0．01），CoPP＋ZnPP组STAT-3高于空白对照组（t=2．7965，P〈0．05），其余各组间差异无统计学意义（P〉0．05）。ZnPP组CAS-3蛋白表达及肿瘤细胞凋亡指数与其他组相比较明显增高（t=3．6856，P〈0．01）（t=3．5969，P〈0．01）。结论ZnPP可能通过抑制HO-1蛋白的表达来降低STAT-3和bcl-XL蛋白表达，从而增加CAS3的表达。并可能由此增加了肿瘤细胞凋亡的发生。     

The protective role of heme oxygenase-1 on the liver after hypoxic preconditioning in rats

BACKGROUND: Hypoxic preconditioning (HP) confers cytoprotection against ischemia/reperfusion (I/R) injury. This effect is in part attributable to the induction of heme oxygenase (HO)-1. This experiment evaluates liver cell damage after I/R injury in HP rats. METHODS: HP rats were prepared by exposure (15 hr/day) to an altitude chamber (5500 m) for 2 weeks. Partial hepatic ischemia was produced in the left lobes for 45 min followed by 180 min of reperfusion. Zinc (Zn) protoporphyrin (PP), a specific inhibitor of HO enzymatic activity, was subcutaneously injected 1 hr before the I/R injury into separate groups of sea-level (SL) control and HP rats. Serum alanine aminotransferase (ALT) levels, liver HO-1 mRNA and protein, and HO enzymatic activity were measured. RESULTS: HO-1 was induced in the livers of rats exposed to HP. The levels of HO-1 mRNA and protein were obviously overexpressed after 2 weeks of HP. HP diminished the elevation of serum ALT levels after I/R injury (83.7+/- 4.9 U/L) when compared with SL controls (280.8+/-19.4 U/L) and HP+ZnPP-pretreated groups (151.3+/-4.4 U/L). The HO activity in treated rats also was correlated with these results (237.9+/-19.8 pmol/mg of protein per hour for the HP group, 164.3+/-12.7 pmol/mg of protein per hour for the HP+ZnPP group, and 182.6+/-8 pmol/mg of protein per hour for the SL controls). CONCLUSIONS: The authors' results indicated that the induction of HO-1 in hypoxic preconditioning played a protective role against hepatic I/R injury.     

Heme Oxygenase-1 Overexpression Protects Rat Livers from Ischemia/Reperfusion Injury with Extended Cold Preservation

This study analyzes the effects and mechanisms of heme oxygenase-1 (HO-1)-mediated cytoprotection in rat livers exposed to cold preservation. In the first series, rats were pretreated with cobalt protoporphyrin (CoPP) or zinc protoporphyrin (ZnPP), HO-1 inducer and antagonist, respectively. Livers were stored at 4 degrees C for 24 h, and then perfused ex vivo for 2 h. Livers pretreated with CoPP had significantly higher portal venous blood flow and increased total bile production, as compared with the ZnPP group. This correlated with histologic (Banff) criteria of hepatocyte injury/liver function. In the second series, rat livers were stored at 4 degrees C for 24 h or 40 h, and then transplanted into syngeneic recipients. After 24 h of preservation, 80% of rats bearing CoPP-pretreated liver grafts survived 21 days (vs. 50% in controls). After 40h of cold preservation, liver transplant survival at day 1, 7 and 21 for the CoPP group was: 100%, 71% and 57%, respectively (vs. 50%, 50% and 33% in controls). This correlated with improved hepatic function/histologic (Suzuki) criteria of hepatocyte injury after HO-1 overexpression (immunohistology/Western blots) by infiltrating macrophages. This study documents the potential utility of HO-1-inducing agents in preventing ischemia/reperfusion injury resulting from prolonged storage of liver transplants.