大鼠脊髓缺血再灌注损伤后神经细胞凋亡及Caspase-1、Caspase-3的表达

目的观察大鼠脊髓缺血再灌注损伤后神经细胞凋亡及Caspase-1、Caspase-3的表达。方法 48只成年健康Wistar大鼠,采用Naslund腹主动脉阻断法制作脊髓缺血再灌注损伤模型。随机分为空白对照组(n=6)、假手术组(n=6)和损伤组(n=36),观察脊髓缺血再灌注损伤后,脊髓的病理变化、细胞凋亡及Caspase-1、Caspase-3的表达变化的规律。结果观察脊髓缺血再灌注损伤后Caspase-1阳性细胞在损伤后12h表达明显,1d损伤区域及周边出现表达高峰。Caspase-3阳性细胞在损伤后12h表达明显,2d损伤区域及周边出现表达高峰。TUNEL阳性细胞也在脊髓损伤后12h表达明显,2d出现表达高峰。空白对照组、假手术组:Caspase-1、Caspase-3免疫组化少有表达,少见TUNEL阳性细胞。结论脊髓缺血再灌注损伤后存在神经细胞凋亡,Caspase-1、Caspase-3均参与损伤的调节。     

大豆异黄酮对脑缺血/再灌注诱导的线粒体损伤和脑细胞凋亡的影响

 目的:研究大豆异黄酮（SI）对全脑缺血/再灌注大鼠脑组织线粒体超微结构、细胞凋亡和细胞色素C（Cyt-C）、caspase-3及caspase-9表达的影响,探讨大豆异黄酮对脑缺血/再灌注损伤的作用及机制。方法: 60只健康成年SD 大鼠随机分为假手术组（sham）、缺血再灌注组（I/R）和大豆异黄酮预处理组（SI）。SI组给予SI 120 mg·kg-1·d-1连续灌胃21 d,其余2组用等体积生理盐水灌胃,每天1次,第22天I/R组和SI组行手术阻断三血管制备全脑缺血/再灌注模型。缺血1 h,再灌1 h后处死,取大脑皮层,光镜观察脑细胞形态学变化,透射电镜观察线粒体超微结构变化,流式细胞术检测细胞凋亡率,半定量RT-PCR法和免疫组织化学法测定脑组织中Cyt-C、caspase-9及caspase-3的表达。结果: I/R组线粒体膜崩解、嵴消失,脑细胞大量凋亡。与I/R组相比,大豆异黄酮预处理能明显改善线粒体超微结构的损伤,减少脑细胞凋亡率（P<0.01）。I/R组Cyt-C、caspase-9和caspase-3 mRNA的表达和蛋白的含量高于sham 组（P<0.01）,与I/R组相比,SI组Cyt-C、 caspase-9及caspase-3 mRNA 和蛋白的表达显著降低（P<0.01）。结论: 大豆异黄酮可能通过稳定线粒体结构,减少线粒体释放Cyt-C,降低caspase-9和caspase-3的表达,抑制细胞凋亡,从而减轻脑缺血/再灌注损伤。     

心肌缺血后处理减轻大鼠缺血/再灌注心肌细胞凋亡及超微结构损伤

缺血预处理(ischemic preconditioning)是减轻缺血/再灌注损伤最有效的方法.Zhao等[1]最近提出的缺血后处理,即心肌缺血后再灌注前反复短暂开通及再闭冠脉,与缺血预处理一样可降低心肌梗死范围及心肌酶释放,但其对心肌细胞凋亡及超微结构的影响国内、外报道较少,尚未见同时从亚细胞水平及细胞凋亡改变评价的报道.     

细胞粘附分子与心肌缺血—再灌注损伤

在细胞缺血－再灌注过程中，细胞粘附分子、尤其是ＣＤ＿（１１）／ＣＤ＿（１８）、选择素家族及ＩＣＡＭ－１等可介导中性粒细胞与血管内皮细胞、中性粒细胞与心肌细胞之间的粘附，通过多种机制造成心肌损伤及血管功能障碍。抗有关细胞粘附分子的单克隆抗体对心肌缺血－再灌注损伤有明显保护作用。     

多巴胺受体2减轻离体大鼠心肌缺血/再灌注损伤

目的 观察多巴胺受体2(DR2)对离体大鼠心肌缺血/再灌注(I/R)损伤的影响及其可能机制.方法 将大鼠40只,每组n=10,随机分成对照组(control)、I/R组、10 pmol/L Bromocriptine(DR2激动剂)组(Bro),10 μmol/L Haloper-idol(DR2抑制剂)组(Hal).用Langendorff离体灌流装置,复制大鼠心肌I/R损伤模型.Powerlab生理记录仪记录心功能;比色法测定冠脉流出液LDH、CK活性和心肌组织匀浆SOD活性以及MDA含量;TUNEL染色检测心肌细胞凋亡;Western blot检测DR2、Bcl-2、caspase-3和caspase-9蛋白的表达.结果 与对照组比较,I/R组DR2、Bcl-2、caspase-3和cmpase-9蛋白表达、LDH和CK活性、MDA含量和细胞凋亡率均增加(P＜0.01),唯有SOD活性降低,心功能减弱(P＜0.01).与I/R组比较,Bro降低LDH和CK活性、MDA含量、细胞凋亡率、caspase-3和caspase-9的表达,升高SOD活性,改善心功能和进一步增加Bcl-2的表达(P ＜0.01);Hal对上述指标影响不显著.结论 DR2可减轻心肌I/R损伤,其机制与抗氧化、清除自由基、上调Bcl-2表达以及下调caspase-3和caspase-9的表达有关.     

萝卜硫素减轻心脏移植模型大鼠缺血/再灌注损伤

目的 研究萝卜硫素在大鼠心脏移植缺血/再灌注损伤(I/RI)中的作用及PI3K/AKT/GSK-3β通路是否参与其中的作用.方法 构建大鼠同种异体活体心脏移植模型为对照组,尾静注射萝卜硫素为萝卜磁素处理组(2.5 mg/kg).比较大鼠的存活率、血清心肌酶、心肌细胞凋亡水平及心肌线粒体的肿胀程度;Western blo...     

白细胞与心肌缺血再灌注损伤

白细胞在心肌缺务再灌注损伤中起着重要作用。通过阻塞毛细血管，产生自由基，促进血小板聚集以及参与花生四烯酸代谢等作用对心肌产生损伤。而通过某些方法抑制白细胞的功能，可使心肌缺血再灌注治疗获得较好的疗效。     

Caspase抑制剂对大鼠心肌缺血／再灌注损伤Fas／FasL表达的影响

目的探讨大鼠心肌缺血／再灌注时caspase抑制剂对心肌细胞凋亡及Fas／FasL基因mRNA表达的影响及其机制。方法以穿线结扎或松扎左冠状动脉制备大鼠心肌缺血／再灌注模型。42只大鼠随机分为假手术组、Z-VAD-fmk治疗组和缺血／再灌注对照组,并分设缺血4-5min后再灌注3,6,12h3个时相点。以缺口末端标记法检测心肌细胞凋亡的变化,逆转录聚合酶链反应法检测Fas／FasL基因mRNA的表达改变,并分析心肌组织病理学损伤程度。结果心肌缺血／再灌注后心肌细胞凋亡指数及Fas/FasL基因mRNA表达均增高,caspase抑制剂预处理下调Fas／FasL表达水平,减少心肌细胞凋亡。结论心肌细胞凋亡与Fas／FasL系统参与了心肌缺血／再灌注损伤过程,caspase抑制剂Z-VAD-fmk通过抑制凋亡和下调Fas／FasL表达,减低再灌注损伤。     

肠上皮细胞凋亡与缺血／再灌注损伤

本文依椐细胞凋亡的特点 ,分别从正常肠上皮细胞凋亡的规律及意义 ,肠道冷、热缺血再灌注损伤时肠上皮细胞凋亡的规律及其机制 ,综述了肠上皮细胞凋亡与缺血再灌注损伤方面的研究进展 ,并提出了存在的问题。     

兔实验性心肌缺血再灌注损伤与心肌细胞凋亡的关系

目的　探讨实验性心肌缺血再灌注损伤时心肌细胞是否凋亡及凋亡率的大小。方法　阻断左冠状动脉的左室支建立家兔心肌缺血模型 ,达到预定的缺血时间后 ,使血管再通 ,建立心肌的缺血再灌注模型。采用透射电镜、原位末端探针标记 ,图像分析 ,对缺血再灌注损伤区心肌细胞的损伤情况进行研究。结果　电镜观察显示缺血再灌注损伤区呈现明显的心肌细胞凋亡征象 ,TUNEL检测结果显示缺血再灌注损伤区出现心肌凋亡阳性细胞 ,平均凋亡率为 2 1 10 %。结论　心肌缺血再灌注损伤的发生与凋亡机制有关 ,并可能是其发生的重要原因。     

小檗碱减轻大鼠心肌缺血再灌注损伤

目的探讨小檗碱(BBR)减轻大鼠心肌缺血再灌注(MI/R)损伤的作用及其与JAK2/STAT3信号通路的关系。方法雄性SD大鼠(250只)随机分为7组(n=36):假手术组(sham)、sham+BBR组、sham+AG490(AG,JAK2/STAT3通路抑制剂)组、MI/R+溶剂组(MI/R+V)、MI/R+BBR组、MI/R+BBR+AG组、MI/R+AG组。常规结扎大鼠冠状动脉左前降支行心肌缺血再灌注手术,缺血30 min后再灌注4 h,用Western blot法检测心肌JAK2、STAT3磷酸化水平及心肌凋亡相关蛋白表达,再灌注6 h后检测心肌细胞凋亡率、梗死面积及氧化应激相关指标,再灌注72 h后检测心功能。结果 BBR可显著改善心肌缺血再灌注术后心功能并减轻心肌凋亡及梗死,这种保护作用可被AG阻断(均P0.05)。BBR治疗还可显著提高心肌JAK2及STAT3磷酸化水平,抑制凋亡相关信号分子表达,这种作用也被AG阻断(P0.05)。结论 BBR可显著减轻大鼠MI/R损伤后心肌梗死及凋亡水平,改善心功能,JAK2/STAT3可能介导此作用。     

α-亚麻酸减轻糖尿病大鼠心肌缺血/再灌注损伤

 目的 研究摄食?-亚麻酸（ALA）对糖尿病大鼠心肌缺血/再灌注（MI/R）损伤的影响。方法 构建高脂饲料-链脲霉素诱导的2型糖尿病大鼠模型（HFD-STZ）,每日灌胃给予正常或HFD-STZ大鼠ALA处理（500 μg/kg）,4周后行心肌缺血（30 min）/再灌注（4或6 h）,并检测心肌梗死范围、血清肌酸激酶（CK）、乳酸脱氢酶（LDH）活性、细胞凋亡,用Western blot检测PI3K、Akt等。结果 HFD-STZ大鼠MI/R损伤加重,虽摄食ALA 4周对正常动物MI/R损伤无影响,但可将HFD-STZ大鼠的心梗面积减小至37.7% ± 5.4%,显著低于对照组的45.6% ± 8.5%（P < 0.05）,且血清CK、LDH活性及细胞凋亡减少;还可增加HFD-STZ大鼠心肌PI3K表达及Akt磷酸化。结论 长期摄食ALA有效减轻糖尿病大鼠MI/R损伤,可能与激活PI3K-Akt信号有关。     

Batroxobin对狗心脏缺血／再灌注损伤中内皮素的影响

本工作研究Batroxobin对狗心脏I／R损伤过程中ET水平的.针狗左冠状动脉前降支结扎30min,恢复血流90min,造成I／R模,于缺血前或缺血后15min静注Batroxobin（1U／kg),测定血浆,心肌ET浓度以及血浆CK和LDH活性。结果表明,I／R组心肌组织及血浆ET水平明显升高,心肌组织明显损伤Batroxobin能够显著降低再灌期血浆及心肌ET水平,降低CK及LDH活性,减轻心肌组织I／R损伤。     

Xanthoangelol alleviates cerebral ischemia reperfusion injury in rats

Ischemia/reperfusion (I/R) injury accounts to be a prime cause of neurological deficit following stroke. This study aimed to explore the neuro-protective effects of Xanthoangelol (XAG) on I/R-induced injury in both in vivo and in vitro models. Our data demonstrated that XAG can shrink infarct size and brain edema in middle cerebral artery occlusion (MCAO) model. In addition, XAG was capable of alleviating the neurological deficit in rats that have undergone MCAO procedure. Meanwhile, antiapoptotic activities of XAG against I/R-induced neuronal injury were evidenced and further illustrated that XAG elicits antiapoptotic activities by suppressing excessive oxidative stress via nuclear factor erythroid-2-related factor 2 activation. Overall, our study revealed that XAG displayed the potential to be utilized as a neuroprotective agent against I/R-induced neurological injury.     

MicroRNA-323 regulates ischemia/reperfusion injury-induced neuronal cell death by targeting BRI3

Purpose: MicroRNA-323 (miR-323) has been reported to be upregulated in Ischemia/Reperfusion (I/R) injury-treated neuronal cell. However, the effect and underlying mechanism of miR-323 in I/R-induced neuronal cell death remains poorly understood. The current study was aim to investigate the role and molecular basis of miR-323 in I/R-induced neuronal cell. Methods: An oxygen-glucose deprivation (OGD) model of hippocampal neuron I/R was produced in vitro. Cell apoptosis, cell survival, and the expression of miR-323 were determined after 6 h, 12 h and 24 h after OGD treatment. The up- or down-regulation of miR-323 was performed by miR-323 mimics or anti-miR-323, respectively. Results: OGD induced apoptosis and suppressed survival in rat hippocampal neurons. And the expression levels of miR-323 were increased after OGD treatment. Furthermore, the up-regulation of miR-323 promoted apoptosis and suppressed survival, whereas the inhibition of miR-323 suppressed apoptosis and enhanced survival in OGD-treated neurons. Moreover, miR-323 could directly bind to BRI3 3’-UTR. Notably, the knockdown of BRI3 by BRI3 siRNA apparently abrogated cell survival and induced cell apoptosis in rat neurons. Conclusion: This study indicated that miR-323 might regulate ischemia/reperfusion-induced rat neuronal cell death via targeting BRI3.     

PI3K/Akt通路介导TRPV1抑制离体小鼠心脏缺血再灌注后的细胞凋亡

目的研究瞬时受体电位香草酸亚型1(TRPV1)对离体小鼠心脏缺血/再灌注(I/R)后心肌细胞凋亡的影响及与PI3K/Akt通路的关系。方法 TRPV1基因敲除(TRPV1~(-/-))和野生型(WT)小鼠各54只,均各随机分为假手术组(sham)、缺血再灌注组(I/R)和LY294002处理组(LY)。建立Langendorff离体心脏灌注模型,检测心功能;灌注结束后,TTC染色法检测心肌梗死面积;TUNEL法检测心肌细胞凋亡;Western blot检测Bcl-2、Bax、Akt和p-Akt的蛋白表达水平。结果 I/R后,TRPV1~(-/-)小鼠较WT小鼠的LVDP明显降低(P0.001),LVEDP明显升高(P0.001),同时心肌梗死面积和心肌凋亡细胞明显增加(P0.01),Bcl-2/Bax和p-Akt表达水平下降(P0.001)。LY294002阻断PI3K后,与相应的I/R组相比,WT小鼠心肌梗死面积明显扩大(P0.001),心肌凋亡细胞明显增加(P0.01),Bcl-2/Bax和p-Akt蛋白表达水平降低(P0.001)。结论 TRPV1可能通过PI3K/Akt通路抑制离体小鼠心脏缺血/再灌注所致的心肌细胞凋亡。     

Circ-RHOJ.1 regulated myocardial cell proliferation and apoptosis via targeting the miR-124-3p/NRG-1 axis in myocardial ischemia/reperfusion injury

IntroductionMyocardial ischemia/reperfusion (I/R) injury is a leading cause of cardiac dysfunction. Circular RNAs (circRNAs) are involved in the pathogenesis of myocardial I/R injury. However, the functions and underlying mechanisms are unclear. The present study determined the role of circ-RHOJ.1 in regulating myocardial cell proliferation and apoptosis after I/R injury.Material and methodsMyocardial cells isolated from Sprague-Dawley rats were identified with an immunofluorescence assay using cardiac troponin T antibody. Expression of circ-RHOJ.1, miR-124-3p and neuregulin-1 (NRG1) mRNA was assessed with real-time quantitative polymerase chain reaction. NRG1 protein expression was evaluated with western blot and immunofluorescence assays. Dual-luciferase reporter assay was performed to confirm interaction between miR-124-3p and circ-RHOJ.1, and miR-124-3p and NRG1. Effects of circ-RHOJ.1 overexpression or miR-124-3p inhibition on cell proliferation and apoptosis were evaluated using cell counting kit (CCK)-8 assay and flow cytometry. Cytokines levels were analyzed with an enzyme-linked immunosorbent assay.ResultsMyocardial cells were successfully isolated and had down-regulated expression of circ-RHOJ.1 and NRG1, and up-regulated expression of miR-124-3p after I/R injury. circ-RHOJ.1 acted as a sponge for miR-124-3p, and NRG1 served as a target gene of miR-124-3p. circ-RHOJ.1 overexpression or miR-124-3p inhibition increased interleukin (IL)-10 levels and reduced IL-2, IL-6, and tumor necrosis factor-α levels in myocardial cells after I/R injury. Functional assay results illustrated that circ-RHOJ.1 overexpression or miR-124-3p inhibition enhanced proliferation and inhibited apoptosis of myocardial cells after I/R injury.ConclusionsCirc-RHOJ.1 served as a molecular marker of myocardial I/R injury via regulation of miR-124-3p and NRG1 expression.     

NADPH氧化酶与脑缺血/再灌注损伤

氧化应激是发生脑缺血/再灌注(ischemia/reperfusion,I/R)损伤的重要机制.近来研究发现,还原型烟酰胺腺嘌呤二核苷酸磷酸(nicotinamide adenine dinucleotide phosphate,NADPH)氧化酶产生的活性氧对脑I/R后的氧化应激起到重要的作用.一些方法(如常压高氧、缺血后处理)和一些药物(如罗布麻宁、替米沙坦、桦木酸、加兰他敏、雷公藤红素等)可以NADPH氧化酶为靶点治疗脑I/R损伤.