红细胞对创伤性脑内出血大鼠脑含水量及HO-1表达的影响

目的研究大鼠创伤性脑内出血(TICH)中红细胞对脑含水量和血红素氧合酶-1(HO-1)表达的影响,并分析二者的关系,以探讨红细胞在TICH后脑水肿形成中的作用机制。方法120只大鼠随机分为创伤性脑损伤组(TBI组),TBI加注全血组(WB组),TBI加注溶解红细胞组(LRBC组)和TBI加注压积红细胞组(PRBC组),每组30只。4组均采用自由落体打击法造成大鼠脑外伤。后3组借助立体定向仪分别向伤区脑皮质内注射全血、溶解红细胞或压积红细胞,造成TICH模型。每组于伤后1、3、5d分别处死10只大鼠,5只测伤区脑组织含水量,5只用免疫组化法检测HO-1的表达。结果4组组内比较:TBI、WB和PRBC3组第3d的脑含水量最高(分别为82.85%±0.60%,85.00%±1.12%,84.93%±1.21%),LRBC组第1d的含水量最高(84.44%±0.85%;4组间比较,1d时LRBC组含水量最高,3d时WB和PRBC组含水量最高。在WB、PRBC和LRBC组,HO-1阳性表达的强弱与脑含水量的高低变化相一致。结论红细胞在TICH后迟发性脑水肿的形成中有重要作用,其机制涉及红细胞的降解产物。     

Influence of bradykinin B1 and B2 receptors in the immune response triggered by renal ischemia–reperfusion injury

Bradykinin B1 receptors are exclusively expressed in inflamed tissues. For this reason, they have been related with the outcomes of several pathologies. Ischemia–reperfusion injury is caused by the activation of inflammatory and cytoprotective genes, such as macrophage chemoattractant protein-1 and heme oxygenase-1, respectively. This study was aimed to analyze the involvement of bradykinin B1 and B2 receptors (B1R and B2R) in tissue response after renal ischemia–reperfusion injury. For that, B1R (B1−/−), B2R (B2−/−) knockout animals and its control (wild-type mice, B1B2+/+) were subjected to renal bilateral ischemia, followed by 24, 48 and 120 h of reperfusion. At these time points, blood serum samples were collected for creatinine and urea dosages. Kidneys were harvested for histology and molecular analyses by real-time PCR. At 24 and 48 h of reperfusion, B1−/− group resulted in the lowest serum creatinine and urea levels, indicating less renal damage, which was proved by renal histology. Renal protection associated with B1−/− mice was also related with higher expression of HO-1 and lower expression of MCP-1. In conclusion, the absence of B1R had a protective role against inflammatory responses developed after renal ischemia–reperfusion injury.     

HO-1在CCK-8减轻脂多糖所致的急性肺损伤中的作用

目的： 探讨血红素氧合酶（HO）-1在八肽胆囊收缩素（CCK-8）减轻脂多糖（LPS）所致急性肺损伤（ALI）中的作用。方法: 将大鼠随机分为5组：正常对照组、LPS组、CCK-8+LPS组、LPS+Hm（氯血红素，CO供体）组、LPS+ZnPP（锌原卟啉，HO-1特异性阻断剂）组。各组给药后2 h、6 h、12 h行支气管肺泡灌洗、检测支气管肺泡灌洗液（BALF）中中性粒细胞（PMN）数目；进行肺组织的形态学观察；测定肺组织中丙二醛（MDA）含量和HO-1蛋白活性；应用RT-PCR和Western blotting技术检测给药后6h肺组织中HO-1 mRNA和蛋白的表达情况。结果: LPS组肺组织出现损伤性变化，同时BALF中PMN数目、肺组织中MDA含量、HO-1蛋白活性、HO-1 mRNA和蛋白的表达均高于相应对照组（均P<0.05）；CCK-8+LPS和LPS+Hm组肺组织损伤程度、BALF中PMN数目和肺组织中MDA含量低于相应LPS组，而肺组织中HO-1蛋白活性、HO-1 mRNA和蛋白的表达均高于相应LPS组（均P<0.05）；LPS+ZnPP组肺组织损伤程度、BALF中PMN数目和肺组织中MDA含量分别高于相应LPS组，而肺组织中HO-1蛋白活性、HO-1 mRNA和蛋白的表达分别低于相应LPS组（均P<0.05）。结论: CCK-8可部分通过HO-1介导的抗氧化、抑制PMN聚集等效应来发挥减轻LPS所致的肺损伤作用。     

The self antigen heme evades immune recognition by sequestration in some hemoproteins

Heme is a non-protein autoantigen which is ubiquitous in vivo, primarily complexed in various hemoproteins or bound to specialized carrier molecules. Nevertheless, heme is able to stimulate a high frequency of CD4⁺, class II-restricted T cells, freshly explanted from unprimed mice, to proliferate in vitro. In this study, we show that heme incorporated into various species of mammalian cytochrome c (cyt c), including murine cyt c, represents a facultative cryptic determinant, able to be recalled only at high doses of native cyt c. By contrast, avian cyt c is of comparable antigenicity to free heme. Artificially denatured carboxymethylated (CM) mammalian cyt c exhibited greatly increased antigenicity, comparable to that of heme and avian cyt c, indicating that the crypticity of heme in native mammalian cyt c is due to the resistance of the native conformation of this molecule to antigen processing within murine antigen-presenting cells. Thus, tolerance to the heme group of at least some hemoproteins, may be maintained by the crypticity of the heme, rather than by deletion of hemereactive T cells. Given the high frequency of heme-reactive T cells in unprimed mice, these findings suggest that heme may become an important modulator during an inflammatory response.     

CO对局灶性缺血脑组织血脑屏障通透性的影响

目的:研究一氧化碳及其限速酶(血红素氧合酶-1)对局灶性缺血脑组织血脑屏障通透性的影响。方法:将SD大鼠随机分为3组(n=6),使用血红素氧合酶诱导剂及抑制剂腹腔注射,用等量生理盐水腹腔注射作为对照组,12h后复制MCAO模型。梗塞后24h后检测血液中一氧化碳浓度、血脑屏障通透性。结果:诱导剂组一氧化碳浓度明显高于对照组(P＜0.01),血脑屏障通透性明显低于对照组(P＜0.05),而抑制剂组一氧化碳浓度明显低于对照组(P＜0.01),血脑屏障通透性明显高于对照组(P＜0.05)。血红素氧合酶诱导剂、抑制剂对非梗塞侧的血脑屏障通透性没有影响(P＞0.05)。结论:一氧化碳作为一种信使分子,脑缺血时浓度升高具有保护血脑屏障的作用。     

银杏叶提取物诱导大鼠主动脉平滑肌细胞HO-1的表达及细胞信号通路研究

目的： 旨在研究银杏叶提取物（Ginkgo Biloba Extract,EGB761）对大鼠主动脉平滑肌细胞(RVSMC)血红素氧合酶-1（HO-1）蛋白的影响,并探讨其中涉及的细胞信号通路。方法: 大鼠主动脉平滑肌细胞株复苏、传代培养到第6代，再复孔培养用于实验，分别给予空白对照、单纯EGB761、EGB761＋锌原卟啉Ⅸ(ZnPPⅨ)或不同的细胞内信号途径特异性阻断剂进行处理，采用Western blotting法定量检测HO-1蛋白表达。结果: EGB761能呈剂量依赖性诱导HO-1蛋白表达，加用ZnPPⅨ（血红素氧合酶特异性阻断剂）及酪氨酸蛋白激酶(TPK)阻断剂木黄酮均能显著抑制EGB761诱导的HO-1蛋白表达（均P<0.01），但calphostin-C（蛋白激酶C阻断剂）、LY294002（磷脂酰肌醇-3激酶阻断剂）及Bay11-7082（核因子-κB阻断剂）对EGB761诱导的HO-1蛋白表达无明显影响（均P>0.05）。结论: (1) EGB761能显著诱导RVSMC中HO-1蛋白的表达，并且这种诱导作用能被血红素氧合酶的特异性阻断剂ZnPPⅨ所阻断。（2）EGB761通过TPK途径介导大鼠主动脉平滑肌细胞HO-1蛋白的表达。     

血红素氧合酶-1对大鼠颈动脉球囊损伤后内膜增殖的影响

目的:观察血红素氧合酶-1(HO-1)对大鼠颈动脉球囊损伤后内膜增殖的影响。方法:健康雄性Wistar大鼠40只,随机分为4组(每组10例)。A组:正常对照组;B组:球囊损伤对照组;C组:氯血红素干预组;D组:原卟啉锌(ZnPP)干预组。A组行假手术(分离颈总动脉,但不损伤内膜),B、C、D组按文献方法制作颈动脉内膜损伤模型。B、C、D组于球囊损伤前3d至术后14d,分别给予0.9%氯化钠溶液1ml/只、氯血红素15mg/kg、ZnPP40μmol/kg隔日1次腹腔注射。球囊损伤后第14天处死大鼠,分离颈总动脉,行苏木精-伊红染色,观察颈动脉内膜增殖情况;RT-PCR及Western blotting分析颈动脉组织HO-1mRNA及蛋白质表达。结果:A组颈动脉内膜无增厚,颈动脉组织无HO-1表达;B组和D组颈动脉内膜明显增厚,D组颈动脉组织无明显HO-1表达,而B组颈动脉组织仅有少量HO-1表达;C组颈动脉内膜增厚明显减轻,HO-1表达量显著增高,与B组和D组比较差异有统计学意义(P<0.01)。结论:氯血红素显著抑制颈动脉球囊损伤后新生内膜的形成,提示HO-1在动脉损伤诱导的新生内膜形成中具有保护作用。     

布地奈德对哮喘大鼠模型肺组织血红素氧合酶-1的调控作用

目的：研究大鼠哮喘模型肺组织血红素氧合酶-1(heme oxygenase-1,HO-1)蛋白及基因表达特点,以及布地奈德(budesonide,BUD)对HO-1蛋白及基因表达的影响。方法：用卵清蛋白(OVA)致敏、激发大鼠建立哮喘动物模型,并在致敏、激发过程中分别经地塞米松(DXM) 、血晶素(Hemin)及BUD处理。分别测定激发后各组动物全血COHb 的百分比含量;计算肺泡灌洗液（BALF）沉渣中细胞总数和分类百分比;进行支气管周围炎性细胞浸润评分;利用免疫组化和RT-PCR检测方式观察HO-1在哮喘大鼠肺组织的蛋白及基因表达。结果：肺组织的病理改变及BALF细胞学检测显示Hemin (H)组、DXM (D)组和BUD (B)组炎性细胞浸润较哮喘(A)组有显著减轻(P<0.01或P<0.05）。与对照(C)组相比,A、H、D和B组HO-1蛋白、基因表达以及碳氧血红蛋白(COHb)含量显著性升高(P<0.01);而与A组相比,H、D和B组HO-1蛋白及mRNA表达亦显著升高(P<0.01或P<0.05）;D组和H组COHb含量显著升高（P<0.05）。结论：哮喘大鼠的肺组织HO-1表达水平及活性显著增加,提示HO-1可能参与了哮喘的发病过程;HO-1对大鼠哮喘模型气道炎症有保护作用;BUD和DXM对大鼠哮喘模型气道炎症有保护作用,可能通过上调肺组织HO-1表达实现。