Curcumin pretreatment and post-treatment both improve the antioxidative ability of neurons with oxygen-glucose deprivation

Recent studies have shown that induced expression of endogenous antioxidative enzymes thr- ough activation of the antioxidant response element/nuclear factor erythroid 2-related factor 2 （Nrf2） pathway may be a neuroprotective strategy. In this study, rat cerebral cortical neurons cultured in vitro were pretreated with 10 ktM curcumin or post-treated with 5 pM curcumin, respectively before or after being subjected to oxygen-glucose deprivation and reoxygenation for 24 hours. Both pretreatment and post-treatment resulted in a significant decrease of cell injury as indicated by propidium iodide/Hoechst 33258 staining, a prominent increase of Nrf2 protein expression as indicated by western blot analysis, and a remarkable increase of protein expression and enzyme activity in whole cell lysates of thioredoxin before ischemia, after ischemia, and after reoxygenation. In addition, post-treatment with curcumin inhibited early DNA/RNA oxidation as indicated by immunocytochemistry and increased nuclear Nrf2 protein by inducing nuclear accumulation of Nrf2. These findings suggest that curcumin activates the expression of thi- oredoxin, an antioxidant protein in the Nrf2 pathway, and protects neurons from death caused by oxygen-glucose deprivation in an in vitro model of ischemia/reperfusion. We speculate that pharmacologic stimulation of antioxidant gene expression may be a promising approach to neu- roprotection after cerebral ischemia.

Effects of electroacupuncture pretreatment on mitochondrial energy metabolism in the rats with myocardial ischemia reperfusion

Objective:To explore the effects of electroacupuncture pretreatment on mitochondrial energy metabolism in the rats with myocardial ischemia reperfusion injury(MIRI).Methods:A total of 60 SPF Wistar rats were randomly divided into a sham-operation group(sham group),a myocardial ischemia reperfusion injury group(MIRI group)and an electroacupuncture pretreatment group(EA group),20 rats in each one.The rats in the sham group and the MIRI group were binded for 7 days,once a day,20 min each time.On the 8th day,the sample was collected after the heart exposed for 50 min in thoractomy in the sham group and the sample was collected after ischemia for 20 min and reperfusion for 30 min in thoractomy in the MIRI group.In the EA group,the pretreatment intervention with electroacupuncture was applied at"Neiguan(内关PC6)","Guanyuan(关元CV4)"and"Zusanli(足三里ST36)"in the rats for 7 days,once a day,20 min each time.On the 8th day,after ischemia for 20 min and reperfusion for 30 min in thoractomy,the sample was collected in the EA group.The changes in STⅡsegment of electroacardiogram(ECG)were observed and measured.Using enzymelinked immunosorbent assay(ELISA),the concentrations of cardiac troponin T(cTnT)and cardiac troponin I(cTnl)were detected.Using nitro blue tetrazolium chloride monohydrate(NBT)staining,the myocardial infarction weight percentage was measured.Using ELISA,the concentrations of mitochondrial adenosine monophosphate(AMP),adenosine diphosphate(ADP)and adenosine triphosphate(ATP)were detected.Results:(1)STⅡchanges:in 20 min of ligation,compared with the sham group,the STⅡsegment of electrocardiograph(ECG)was elevated significantly in the MIRI group and EA group(both P<0.01),but the elevation range in the EA group was lower than that of the MIRI group(P<0.01).After reperfusion for30 min,the STⅡsegment was fallen by over 50%in the MIRI group and the EA group.Simultaneously,the STⅡsegment in the EA group was lower than that of the MIRI group(P<0.01).(2)Regarding myocardial infarction weight percentage,compared with the sham group,the infarction weight was larger in the MIRI group and the EA group(both P<0.05)and the infarction weight in the EA group was lower than that of the MIRI group(P<0.05).(3)Regarding the levels of serum cTnt and cTnI,compared with the sham group,the levels of serum cTnT and cTnI were higher in the MIRI group and the EA group(all P<0.01)and the levels of cTnT and cTnI in the EA group were lower than that of the MIRI group(both P<0.01).(4)Regarding the concentrations of AMP,ADP and ATP,compared with the sham group,ATP concentration was lower in the MIRI group and the EA group(both P<0.01)and the concentrations of AMP and ADP were higher(P<0.05,P<0.01).Compared with the MIRI group,ATP concentration was higher in the EA group(P<0.05)and the concentrations of AMP and ADP were lower(both P<0.01).Conclusions:Electroacupuncture pretreatment reduces the elevation of ECG STⅡsegment,decreases the concentrations of myocardial injury markers,cTnT and cTnI and regulates the transfer among AMP,ATP and ADP.The protective effect of electroacupuncture pretreatment may result from the regulation of mitochondrial energy metabolism.

microRNA-455-5p alleviates neuroinflammation in cerebral ischemia/reperfusion injury

Neuroinflammation is a major pathophysiological factor that results in the development of brain injury after cerebral ischemia/reperfusion.Downregulation of microRNA(miR)-455-5p after ischemic stroke has been considered a potential biomarker and therapeutic target for neuronal injury after ischemia.However,the role of miR-455-5p in the post-ischemia/reperfusion inflammatory response and the underlying mechanism have not been evaluated.In this study,mouse models of cerebral ischemia/reperfusion injury were established by transient occlusion of the middle cerebral artery for 1 hour followed by reperfusion.Agomir-455-5p,antagomir-455-5p,and their negative controls were injected intracerebroventricularly 2 hours before or 0 and 1 hour after middle cerebral artery occlusion(MCAO).The results showed that cerebral ischemia/reperfusion decreased miR-455-5p expression in the brain tissue and the peripheral blood.Agomir-455-5p pretreatment increased miR-455-5p expression in the brain tissue,reduced the cerebral infarct volume,and improved neurological function.Furthermore,primary cultured microglia were exposed to oxygen-glucose deprivation for 3 hours followed by 21 hours of reoxygenation to mimic cerebral ischemia/reperfusion.miR-455-5p reduced C-C chemokine receptor type 5 mRNA and protein levels,inhibited microglia activation,and reduced the production of the inflammatory factors tumor necrosis factor-αand interleukin-1β.These results suggest that miR-455-5p is a potential biomarker and therapeutic target for the treatment of cerebral ischemia/reperfusion injury and that it alleviates cerebral ischemia/reperfusion injury by inhibiting C-C chemokine receptor type 5 expression and reducing the neuroinflammatory response.

Induction of Autologous Bone-Marrow Stem Cells by Low-Level Laser Therapy Has Beneficial Effects on the Kidneys Post-Ischemia-Reperfusion Injury in the Rat

Acute renal failure has a 50% - 80% mortality rate. Currently, treatment options for this life-threatening disease are limited. Low-level laser therapy (LLLT) has been found to modulate biological activity. The aim of the present study was to investigate the possible beneficial effects of laser application to stem cells in the bone marrow, on the kidneys of rats that had undergone ischemia-reperfusion injury (IRI). IRI was induced by occlusion of the renal artery to 3- and 7-month-old rats for 15 or 30 minutes. In an additional experiment IRI was applied to both kidneys for 20 min each in 2-3-month-old rats. Rats were then divided randomly into two groups of control and laser-treated. Laser therapy (Ga-Al-As 810 nm, 200 mW output for 2 min) was applied to the bone marrow 1 and 7 days post-IRI to the kidneys, and rats were sacrificed 2 weeks later. Histomorphometry and immunohistochemistry were performed on kidney sections and blood markers for kidney function. Quantitative histomorphometric analysis revealed a reduction in dilatation of the renal tubules, restored structural integrity of the renal tubules, and reduced necrosis in the laser-treated rats as compared to the control, non-laser-irradiated group. C-kit positive cell density in kidneys post-IRI and laser-treatment was significantly (p = 0.015) 3.2-fold higher compared to the control group. Creatinine and blood urea nitrogen content were significantly lower in the laser-treated rats as compared to control. It is concluded that LLLT application to the bone marrow (BM) causes a significant increase in the density of mesenchymal stem cells in the kidneys post-IRI, probably by induction of stem cells in the BM, which subsequently migrate to the IRI kidney, significantly reducing the pathological features of the kidney and increasing kidney function post IRI.

七氟醚预处理和后处理对局灶性脑缺血再灌注损伤大鼠神经元坏死性凋亡的影响

目的参照改良Zea-longa线栓法建立局灶性脑缺血再灌注损伤的大鼠模型,观察七氟醚处理对局灶性脑缺血再灌注损伤大鼠神经元的影响,并探讨其作用机制。方法选取成年雄性SD大鼠进行实验,按随机分组原则分为4组:假手术(Sham)组、缺血再灌注(IR)组、七氟醚预处理(Spre)组、七氟醚后处理(Spo)组,每组各10只。造模结束后,采用Longa评分法评测神经行为学;酶联免疫吸附测定(ELISA)法检测大鼠脑组织中超氧化物歧化酶(SOD)活性及丙二醛(MDA)水平;采用Western blotting检测蛋白还原型烟酰胺腺嘌呤二核苷酸磷酸氧化酶4(NOX4)、Caspase3的表达情况;流式细胞术检测细胞凋亡情况。结果相对于Sham组,IR组的神经行为学评分、MDA水平、NOX4、Caspase3的表达、神经元凋亡数明显升高,SOD活性降低,差异有统计学意义(P<0.05);与IR组相比,Spre组和Spo组的神经行为学评分、MDA水平、NOX4、Caspase3的表达、神经元凋亡数明显降低,SOD活性升高,差异均有统计学意义(P<0.05)。结论在局灶性脑缺血再灌注损伤模型大鼠中,七氟醚预处理和后处理对缺血再灌注大鼠脑组织均有一定的保护作用,其保护作用可能通过抑制氧化应激损伤导致的神经元坏死性凋亡来实现的。

皮瓣缺血再灌注损伤的发病机制及治疗进展

背景:皮瓣移植技术是治疗严重组织缺损的常用外科手术方式,但术后因缺血再灌注损伤容易引发皮瓣坏死,因此提高移植皮瓣的存活率仍是目前重要的研究课题。目的:综述皮瓣缺血再灌注损伤的发病机制及最新治疗进展。方法:检索CNKI、万方和PubMed数据库中2014-2024年发表的相关文献,中文检索词为“皮瓣,缺血再灌注损伤,炎症反应,氧化应激反应,Ca^(2+)超载,细胞凋亡,间充质干细胞,富血小板血浆,信号通路,冲击波,预处理”,英文检索词为“flap,ischemia-reperfusion injury,inflammatory response,oxidative stress,Ca^(2+)overload,apoptosis,mesenchymal stem cells,platelet-rich plasma,signaling pathways,Shock wave,Pretreatment”。通过阅读文章剔除研究内容与文章主题关系不大、质量较差及内容陈旧文献,最终纳入77篇文献进行归纳总结。结果与结论:皮瓣缺血再灌注损伤损伤可能与炎症反应、氧化应激反应、Ca^(2+)超载、细胞凋亡等病理因素有关,引起皮瓣血管内皮细胞凋亡、血管损伤和微循环障碍,最终导致皮瓣坏死。研究发现,间充质干细胞移植、富血小板血浆、信号通路调节剂、冲击波及预处理等治疗方法均可以从不同方向在不同程度上缓解皮瓣缺血再灌注损伤,降低移植皮瓣的坏死率和坏死面积。关于皮瓣缺血再灌注损伤的治疗方法虽然很多,然而临床还未形成统一有效的治疗方法,各种治疗方法的优缺点也未进行对比研究,并且大部分研究都停留在动物实验阶段,临床观察研究甚少,因此未来还需要进行大量研究,逐步由动物实验向临床迈进,以便更好地为临床服务。

提高间充质干细胞治疗皮瓣缺血再灌注损伤的策略

背景:间充质干细胞在治疗皮瓣缺血再灌注损伤方面潜力巨大,然而其自身的缺陷及在治疗皮瓣缺血再灌注损伤中的作用下降等原因限制了其广泛应用。目的:综述提高间充质干细胞治疗皮瓣缺血再灌注损伤的策略,为其进一步理论研究和临床应用提供参考。方法:检索中国知网、万方和PubMed数据库收录的相关文献。中文检索词为“间充质干细胞,皮瓣缺血再灌注损伤,间充质基质细胞,干细胞,皮瓣,缺血再灌注损伤,预处理,基因修饰,生物材料封装,联合运用”。英文检索词为“mesenchymal stem cell,Ischemia-reperfusion injury of skin flap,Mesenchymal stromal cells,Stem cells,skin flap,Ischemia-reperfusion injury,Pretreatment,Gene modification,Biomaterial packaging,Joint application”。检索2007年以来发表的相关文献,通过阅读文章剔除研究内容与文章主题关系不大、质量较差及内容陈旧的文献,最终纳入75篇文献进行归纳总结。结果与结论:①间充质干细胞具有抑制炎症反应、抗氧化应激以及诱导血管新生等显著作用,在治疗皮瓣缺血再灌注损伤中蕴含着巨大潜力。②尽管间充质干细胞在治疗皮瓣缺血再灌注损伤中显示出了巨大潜力,但其在治疗上存在的缺陷限制了在临床上的广泛运用,通过预处理(细胞因子、低氧、药物及其他预处理间充质干细胞)、基因修饰间充质干细胞、生物材料封装间充质干细胞以及间充质干细胞和其他药物或治疗方法联合运用等,这些方法不仅可以克服间充质干细胞在治疗上的缺陷,还提高了其在皮瓣缺血再灌注损伤方面的治疗效果。③因此,在未来进一步提高间充质干细胞治疗皮瓣缺血再灌注损伤的效果,挖掘其治疗潜力,对于间充质干细胞的研究和皮瓣缺血再灌注损伤的治疗都具有非常重要的意义。

电针预处理通过调控AKT/mTOR信号通路减轻缺血再灌注大鼠心肌损伤

目的观察电针预处理对心肌缺血再灌注损伤大鼠的影响并探讨其作用机制。方法30只SD大鼠随机抽取6只为假手术组(只穿线不结扎),剩余大鼠采用冠脉结扎法建立心肌缺血再灌注损失(MIRI)大鼠模型,并在造模前1周分别进行电针内关预处理、雷帕霉素预处理和雷帕霉素+电针内关预处理。造模结束后用HE染色法检测心肌细胞病理形态学变化;ELISA法检测血清中CK-MB和IL-6含量;Western-blot法检测Beclin1、Caspase3及磷酸化的AKT、mTOR蛋白表达。结果与模型组比较,电针组心肌纤维断裂减少、细胞间质出血减少,其损伤程度与假手术组较为接近;与雷帕霉素组比较,雷帕霉素+电针组心肌纤维断裂减少、细胞水肿程度减轻。与假手术组比较,模型组大鼠CK-MB、IL-6、Beclin1和Caspase3表达明显升高,p-AKT、p-mTOR表达明显下调(P<0.01);与模型组比较,电针组大鼠CK-MB、IL-6、Beclin1和Caspase3表达明显下调,p-AKT、p-mTOR表达明显升高(P<0.01);与电针组比较,雷帕霉素+电针组大鼠IL-6、CK-MB、Beclin1和Caspase3表达明显升高(P<0.05或P<0.01),p-AKT、p-mTOR表达明显下调(P<0.01)。结论电针内关预处理减轻大鼠MIRI可能与激活AKT/mTOR信号通路相关。

心肌缺血再灌注损伤大鼠HMGB1表达水平的Meta分析

目的对心肌缺血再灌注损伤(MIRI)大鼠高迁移率族蛋白B1(HMGB1)表达水平进行Meta分析。方法在PubMed、Embase及中国国家知识基础设施(CNKI)数据库检索相关文章,最终共纳入16篇文献,从这些文章中提取假手术组、模型组、预处理组的样本量、均数和标准差,采用SYRCLE动物实验风险评估工具进行方法学质量评价,应用Stata12.0软件进行Meta分析。结果MIRI大鼠模型组HMGB1表达水平显著高于假手术组(SMD=8.66,95%CI:6.49~10.82,P<0.001),MIRI大鼠预处理组HMGB1表达水平明显低于模型组(SMD=-3.33,95%CI:-4.22~-2.44,P<0.001)。亚组分析表明,不同预处理方式可能导致异质性存在。敏感性分析显示Meta分析结果可信度较高,而漏斗图显示存在发表偏倚。结论MIRI大鼠HMGB1表达水平升高,通过治疗可降低MIRI大鼠HMGB1表达水平。

TSNⅡA对大鼠IRI肾脏TLR4/NF-κB信号通路的影响

目的探讨丹参酮ⅡA(TSNⅡA)对大鼠肾脏缺血再灌注损伤(IRI)肾脏Toll样受体4(TLR4)/核转录因子-κB(NF-κB)信号通路的影响及对炎症因子水平的下调作用,并分析其对肾脏IRI保护作用机制。方法选取雄性Wistar大鼠建立大鼠肾IRI模型,采用随机数字表表法随机分为五组,每组12只,其中A组大鼠为假手术组;B组为IRI模型组;C组为ST2825干预组,注射ST2825(100 mg/kg);D组为Bay-7082干预组,注射Bay-7082(50μg/kg);E组为TSNⅡA干预组:实验前3 d开始TSNⅡA干预组股静脉注射丹参酮ⅡA注射液(5 mg/kg),每天1次。18 h后,取大鼠下腔静脉血液2 ml,检测血清肿瘤坏死因子(TNF-α)、白细胞介素1(IL-1)、白细胞介素6(IL-6)浓度,并处死大鼠,应用免疫组化法检测肾脏TLR4和NF-κB阳性表达率。结果 B、C、D和E组TLR4和NF-κB阳性率均高于A组,C、D和E组TLR4和NF-κB阳性率均低于B组,E组TLR4和NF-κB阳性率分别为(38.27±2.87)%和(40.76±4.20)%,均高于C和D组,差异均具有统计学意义(P<0.05)。B、C、D和E组血清TNF-α、IL-1和IL-6水平均高于A组,C、D和E组血清TNF-α、IL-1和IL-6水平均低于B组,E组血清TNF-α、IL-1和IL-6水平分别为(76.02±4.28)pg/L、(86.41±6.32)ng/L和(80.28±5.60)ng/L,均高于C和D组,差异均具有统计学意义(P<0.05)。结论TSNⅡA能够下调大鼠肾脏TLR4和NF-κB水平,抑制TLR4/NF-κB信号通路,降低炎症因子水平,实现对肾脏IRI的改善与保护作用。

Shenmai Injection Attenuates Myocardial Ischemia/Reperfusion Injury by Targeting Nrf2/GPX4 Signalling-Mediated Ferroptosis

Objective:To examine the effect of Shenmai Injection(SMJ)on ferroptosis during myocardial ischemia reperfusion(I/R)injury in rats and the underlying mechanism.Methods:A total of 120SPF-grade adult male SD rats,weighing 220–250 g were randomly divided into different groups according to a random number table.Myocardial I/R model was established by occluding the left anterior descending artery for 30 min followed by 120 min of reperfusion.SMJ was injected intraperitoneally at the onset of 120 min of reperfusion,and erastin(an agonist of ferroptosis),ferrostatin-1(Fer-1,an inhibitor of ferroptosis)and ML385(an inhibitor of nuclear factor erythroid-2 related factor 2(Nrf2))were administered intraperitoneally separately 30 min before myocardial ischemia as different pretreatments.Cardiac function before ischemia,after ischemia and after reperfusion was analysed.Pathological changes in the myocardium and the ultrastructure of cardiomyocytes were observed,and the myocardial infarction area was measured.Additionally,the concentration of Fein heart tissues and the levels of creatine kinase-MB(CK-MB),troponin I(cTnI),malondialdehyde(MDA)and superoxide dismutase(SOD)in serum were measured using assay kits,and the expressions of Nrf2,glutathione peroxidase 4(GPX4)and acyl-CoA synthetase long-chain family member 4(ACSL4)were examined by Western blot.Results:Compared with the sham group,I/R significantly injured heart tissues,as evidenced by the disordered,ruptured and oedematous myocardial fibres;the increases in infarct size,serum CK-MB,cTnI and MDA levels,and myocardial Feconcentrations;and the decreases in SOD activity(P<0.05).These results were accompanied by ultrastructural alterations to the mitochondria,increased expression of ACSL4 and inhibited the activation of Nrf2/GPX4 signalling(P<0.05).Compared with the I/R group,pretreatment with 9 mL/kg SMJ and 2 mg/kg Fer-1 significantly reduced myocardial I/R injury,Feconcentrations and ACSL4 expression and attenuated mitochondrial impairment,while 14 mg/kg erastin exacerbated myocardial I/R injury(P<0.05).In addition,cardioprotection provided by 9 mL/kg SMJ was completely reversed by ML385,as evidenced by the increased myocardial infarct size,CK-MB,cTnI,MDA and Feconcentrations,and the decreased SOD activity(P<0.05).Conclusions:Ferroptosis is involved in myocardial I/R injury.Pretreatment with SMJ alleviated myocardial I/R injury by activating Nrf2/GPX4 signalling-mediated ferroptosis,thereby providing a strategy for the prevention and treatment of ischemic heart diseases.

BMSCs对IRI大鼠肾小管病理、ROCK蛋白水平的影响

目的研究骨髓间充质干细胞(Bone Marrow Mesenchymal Stem Cells,BMSCs)移植对缺血再灌注损伤(Ischemia Reperfusion Injury,IRI)大鼠肾小管病理、Rho相关卷曲螺旋形成蛋白激酶(Rho Associated Coiled Coil Forming Protein Kinase,ROCK)蛋白水平的影响。方法把30只大鼠随机分为sham组、IRI组和BMSCs组,每组各10只。比较三组大鼠的生化指标和肾组织病理变化,观察三组大鼠肾小管上皮细胞的增殖和凋亡情况,最后比较三组大鼠肾组织中ROCK蛋白的表达情况。结果与sham组大鼠相比较,IRI组大鼠的血肌酐(Serum Creatinine,SCr)和尿素氮(Blood Urea Nitrogen,BUN)水平均显著增高(P<0.05);BMCSs组大鼠的SCr和BUN水平明显低于IRI组大鼠(P<0.05)。IRI组大鼠的肾小管出现严重损坏,肾小管管腔有明显的扩张现象,肾小管上皮细胞也出现肿胀和坏死的现象,管型呈红细胞或颗粒状,肾间质大量的出血和水肿。与IRI组大鼠比较,BMSCs组大鼠的肾单位损伤较轻,肾组织情况得到了明显的改善。与sham组大鼠肾小管上皮细胞中PCNA阳性表达比较,IRI组大鼠PCNA阳性表达显著降低(P<0.05);BMSCs组大鼠的阳性细胞数量显著多于IRI组大鼠。IRI组大鼠的凋亡细胞显著多于sham组,并且在细胞核中存在大量核固缩;BMSCs组大鼠的凋亡情况显著低于IRI组大鼠。与sham组大鼠比较,IRI组大鼠的RhoA蛋白和ROCKⅠ蛋白表达显著增加(P<0.05);BMSCs组大鼠的RhoA蛋白和ROCKⅠ蛋白表达显著低于IRI组(P<0.05)。结论BMSCs可有效的保护肾缺血再灌注损伤导致的肾小管损伤,同时抑制肾组织中ROCK蛋白表达,从而对肾脏起到保护作用。

针灸预处理防治心肌缺血再灌注损伤研究进展

近年来,心血管疾病的发病率及致死率不断增长,其病因多为心脏冠状动脉发生阻塞,导致心肌供血不足,临床治疗均采取手段恢复心肌供血,而梗死区血流恢复再灌注会导致严重的再灌注损伤,严重危害着人们的生命健康。因此,目前对心血管疾病的研究重点之一就是解决心肌缺血再灌注损伤问题。大量实验研究表明,针灸预处理对心肌缺血再灌注损伤有积极的保护作用。该文对近年来心肌缺血再灌注损伤的针灸预处理方式进行了梳理,具体疗法以电针治疗为主,向温和灸、麦粒灸等多种手段干预发展,选穴方面内关穴是选用频率最高的腧穴,且内关穴治疗再灌注损伤具有特异性,也有学者对预处理的介入时间进行了对比。此外,研究指出针灸预处理的作用机制主要涉及调控细胞自噬、抑制细胞凋亡、抑制氧化应激、减轻炎性损害、调节腺苷受体以及神经调控。

右美托咪定预处理通过PI3K/Akt/mTOR信号通路对心肌缺血再灌注大鼠心脏损伤和心肌组织自噬的影响

目的:探讨右美托咪定预处理通过磷脂酰肌醇3-激酶/蛋白激酶B/雷帕霉素靶蛋白(PI3K/Akt/mTOR)信号通路对心肌缺血再灌注大鼠心脏损伤和心肌组织自噬的影响。方法:60只SD大鼠随机分为假手术组(n=20)、心肌缺血再灌注组(n=20)和右美托咪定预处理组(n=20),建立心肌缺血再灌注损伤模型。假手术组仅接受假手术而不造成心肌缺血,右美托咪定预处理组输注右美托咪定。比较各组大鼠心脏损伤、心肌细胞自噬、PI3K/Akt/mTOR表达、氧化应激及炎症指标。结果:与假手术组比较,右美托咪定预处理组、心肌缺血再灌注组血清肌酸激酶同工酶(CK-MB)、乳酸脱氢酶(LDH)水平依次升高,且右美托咪定预处理组心肌梗死面积百分比明显小于心肌缺血再灌注组(均P<0.05)。与假手术组比较,右美托咪定预处理组、心肌缺血再灌注组心肌组织中LC3、Beclin、P62蛋白表达依次升高(均P<0.05)。与假手术组比较,右美托咪定预处理组、心肌缺血再灌注组心肌组织中PI3K/Akt/mTOR表达依次下降(均P<0.05)。与假手术组比较,右美托咪定预处理组、心肌缺血再灌注组血清髓过氧化物酶(MPO)、丙二醛(MDA)水平依次升高,血清超氧化物歧化酶(SOD)水平依次下降(均P<0.05)。与假手术组比较,右美托咪定预处理组、心肌缺血再灌注组血清白介素-6(IL-6)、白介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)水平依次升高(均P<0.05)。结论:右美托咪定预处理能够保护心肌缺血再灌注损伤大鼠心脏功能,可抑制炎症因子表达、减轻氧化应激反应,其作用机制可能与下调心肌细胞自噬蛋白表达,从而激活PI3K/Akt/mTOR信号通路有关。

电针预处理对脑缺血再灌注损伤大鼠神经功能及缺血半暗带区VEGF、CD31表达的影响

目的通过观察电针预处理对脑缺血再灌注损伤大鼠神经功能、脑梗死体积及半暗带区脑组织血管内皮生长因子(vascular endothelial growth factor,VEGF)、血小板-内皮细胞黏附分子(platelet endothelial cell adhesion molecule-1,CD31)表达的影响,判断电针预处理对半暗带区血管新生的影响,探索电针预处理改善脑缺血再灌注损伤的可能作用机制。方法将36只SD大鼠按照随机数字表法分为假手术组、模型组、电针预处理组,每组12只。电针预处理组予以电针百会、水沟、大椎,每天1次,共7次;假手术组、模型组仅捆绑,不予电针处理。实验第8天,参照Zea Longa方法对模型组、电针预处理组进行大脑动脉栓塞(medial cerebral artery occlusion,MCAO)造模后灌注,假手术组仅切开皮肤暴露颈动脉,不做手术。造模24 h后,对各组大鼠进行神经功能缺损评分(neurological severity scores,NSS)法评估神经功能,评分后取大鼠梗死侧脑半球行红四氮唑(2,3,5-Triphenyltetrazolium Chloride,TTC)染色检测脑梗死面积,取脑缺血半暗带区组织进行HE染色观察脑组织形态变化,免疫组织化学法测定VEGF、CD31表达。结果假手术组未见梗死以及任何神经功能损伤,细胞形态正常;模型组半暗带区细胞损伤显著增加,排列紊乱,呈肿胀状,毛细血管管腔塌陷;电针预处理组损伤程度减轻,排列轻度紊乱,细胞肿胀不明显。与假手术组比较,模型组大鼠神经功能缺损评分明显升高(P<0.01),脑梗死面积明显增加(P<0.01),缺血半暗带区VEGF、CD31表达明显增加(P<0.01);与模型组比较,电针预处理组大鼠神经功能缺损评分降低(P<0.05),脑梗死面积明显减少(P<0.01),缺血半暗带区VEGF、CD31表达明显增加(P<0.01)。结论电针预处理可能通过促进缺血半暗带区血管新生,从而改善脑缺血再灌注损伤大鼠神经功能损伤、降低脑梗死体积。

电针预处理对脑缺血再灌注大鼠HO-1表达及脑血流、神经功能、脑梗死体积的影响

目的观察电针预处理对脑缺血再灌注损伤大鼠血清血红素氧合酶-1(HO-1)表达以及脑血流量、神经功能、脑梗死体积的影响。方法27只成年雄性SD大鼠按照随机数字表法分为假手术组、模型组和电针预处理组,每组各9只。假手术组除不插入线栓外,其余同模型组;模型组造模前束缚14 d,采用线栓法制备大脑中动脉缺血再灌注模型;电针预处理组在造模前14 d行EA预处理,其余同模型组。比较大鼠造模即刻、造模后和再灌注后的脑血流量,造模后24 h的Bederson评分、改良神经功能缺损评分(mNSS)及脑梗死体积;采用Morris水迷宫实验测试空间学习记忆能力;并采用酶联免疫吸附试验检测血清HO-1浓度变化。结果造模即刻,造模后60、120 min,再灌注即刻,再灌注后10、20、30 min,与假手术组比较,模型组大鼠脑血流量明显降低,差异均有统计学意义(P<0.05);与模型组比较,电针预处理组大鼠脑血流量明显升高,差异均有统计学意义(P<0.05)。造模后24 h,与假手术组比较,模型组大鼠Bederson评分、mNSS评分增加,差异均有统计学意义(P<0.05);与模型组比较,电针预处理组Bederson评分、mNSS评分均降低,差异均有统计学意义(P<0.05)。造模后24 h,假手术组TTC染色无梗死灶形成,模型组与电针预处理组均可见不同程度灰白色梗死灶。与模型组比较,电针预处理组脑梗死占比明显减小,差异有统计学意义(P<0.05)。假手术组与模型组大鼠的第四象限滞留时间百分比和血清HO-1水平比较,差异均无统计学意义(P>0.05);与模型组比较,电针预处理组大鼠的第四象限滞留时间百分比和血清HO-1水平均明显升高,差异均有统计学意义(P<0.05)。结论电针预处理可有效恢复脑血流,改善神经缺损功能,减小脑梗死体积,提高认知水平,从而在脑缺血再灌注损伤中发挥一定的保护作用。其机制可能与提高模型大鼠血清中HO-1蛋白表达水平发挥抗氧化应激作用有关。

电针预处理对心肌缺血再灌注损伤小鼠下丘脑腹内侧核神经元活动的影响

目的 观察电针预处理心经经穴对心肌缺血再灌注损伤(myocardial ischemia-reperfusion injury, MIRI)小鼠下丘脑腹内侧核(ventromedial hypothalamic nucleus, VMH)神经元活动的影响,探讨电针预处理抗MIRI的中枢调控机制。方法 将36只C57BL/6小鼠随机分为假手术组、模型组、电针组,每组12只;电针组选取双侧神门、通里穴进行电针预处理,每次30 min,每日1次,共干预7 d,末次电针预处理结束后1 h内进行MIRI模型复制;模型组和假手术组小鼠不予电针。采用Powerlab多导生理记录仪和Chart软件记录并分析各组小鼠模型复制前、缺血30 min、再灌注120 min时ST段电压值的变化;苏木精—伊红(hemaxylin eosin, HE)染色法观察各组小鼠心肌组织病理变化;免疫荧光染色法观察各组小鼠VMH中c-fos表达情况以及模型组小鼠VMH中c-fos分别与谷氨酸、γ-氨基丁酸共表达情况;采集、分析和比较各组小鼠VMH神经元电活动。结果 与假手术组比较,模型组小鼠结扎30 min及再灌注120 min时ST段电压值均显著升高(P<0.05),HE染色可见小鼠心肌组织损伤严重,VMH中c-fos阳性细胞数显著增加(P<0.05),VMH锥体神经元放电次数显著增加(P<0.05),中间神经元放电次数显著减少(P<0.05),VMH神经元局部场电位频谱能量增强,放电频率较为密集;与模型组比较,电针组小鼠结扎30 min及再灌注120 min时ST段电压值均显著降低(P<0.05),HE染色可见心肌组织损伤较轻,VMH中c-fos阳性细胞数显著减少(P<0.05),VMH锥体神经元放电次数显著减少(P<0.05),中间神经元放电次数差异无统计学意义(P>0.05),VMH神经元局部场电位频谱能量降低,放电频率较为疏散。模型组小鼠VMH中c-fos与谷氨酸能神经元的共表达量高于与γ-氨基丁酸能神经元的共表达量(P<0.05)。结论 电针预处理心经经穴可降低小鼠VMH锥体神经元放电频率和c-fos表达水平,减轻心肌损伤,VMH中谷氨酸能神经元参与了电针抗MIRI的中枢整合机制。

Influence of extract of Ginkgo biloba leaves tablets on the aquaporin-1 expression in isolated lung ischemia reperfusion

Background The extract of Ginkgo biloba leaves tablets, ginaton, is widely used in treating ischemic cerebrovascular disease in the clinic. This study aimed to investigate the expression of aquaporin-1 （AQP-1） in rat lung with ischemia/ reperfusion injury after pretreatment with ginaton, and whether the pretreatment with ginaton reduces the acute lung injury caused by ischemia/reperfusion injury. Methods Adult Wistar rats were divided into two groups. Some rats were used as donors （n=20）, the others as recipients （n=20）. Left lungs of donor rats were used for the isolated lung reperfusion model, which perfused only with low potassium dextran （LPD） solution as group A （n=10）; the others were pretreated with ginaton before reperfusion as group C （n=10）. Right lung of donor rat without any treatment was used as a control group （group B and group D, n=10 for each group）. After the model was established, the expression of AQP-1 in the lung tissues was examined by immunohistochemistry, Western blotting, and reverse transcriptase-polymerase chain reaction. Results Immunohistochemical examination revealed that AQP-1 was expressed in endothelia. Immunoblotting demonstrated that the relative gray values of AQP-1 protein in groups A and C were 0.65±0.06, 0.88±0.11, respectively. The relative gray values of the mRNA expression in groups A and C were 0.30±0.08, 0.49±0.11, respectively. The expression of AQP-1 protein and mRNA in group C was significantly higher than in group A （P 〈0.05）. Conclusion The pretreatment with ginaton can reduce the acute lung injury caused by ischemia/reperfusion.

Continuous Monitoring of Serum Tumor Necrosis Factor-α for Patients with TEMIS Treated by Nitrates Postconditioning during PCI

Objective: To investigate the protective effect of nitrates postconditioning on myocardial ischemia-reperfusion injury and whether it plays a regulatory role in TNF-α in patients with STEMI during PCI. Methods: Patients with STEMI who underwent PCI were selected, except for obvious anemia, head trauma, cerebral hemorrhage, hypotension (systolic blood pressure less than 90 mmHg), and patients with autoimmune diseases, all kinds of acute and chronic infections and malignant tumors. They were randomly divided into PCI standardized treatment group and isosorbide dinitrate postconditioning during PCI group. The concentrations of cTnI and TNF-α in serum were detected by ELISA method in each group before PCI and after 2 hours, 1 day, 4 days and 7 days of PCI. Results: 1) There were no statistically significant differences in sex, age, smoking history, diabetes, hypertension and blood lipid abnormality in two groups. 2) Before operation, the concentration of cTnI in two groups was not statistically significant. The concentration of cTnI in the experimental group was lower than that of the control group after 4 days and 7 days of PCI, and P α in two groups before operation. The concentration of TNF-α in the experimental group was lower than that in the control group after 1 day, 4 days and 7 days of PCI, and P α in two groups was both in 1 day after operation, and the peak level of the experimental group and the level of each time after the operation were lower than that of the control group. Conclusion: Nitrates postconditioning during PCI in patients with STEMI has a protective effect on myocardial ischemia-reperfusion injury. Nitrates postconditioning has an effect to reduce the level of TNF-α of patients with STEMI after PCI treatment, and may have the mechanism of alleviating the inflammatory response after myocardial ischemia and reperfusion.

右美托咪定预处理对视网膜缺血再灌注损伤的保护效应及机制研究

目的:探究右美托咪定预处理对视网膜缺血再灌注损伤的保护效应及机制研究。方法:随机挑选30只雄性大鼠,分为健康组、缺血组和预处理组,每组各10只。健康组大鼠各项指标均正常,缺血组采用高眼压法制造的大鼠视网膜缺血再灌注模型,预处理组对缺血组小鼠进行了右美托咪定预处理。分别于缺血前15 min作用及再灌注前5 min左右,健康组及缺血组按照5 mL/kg大鼠体重进行生理盐水灌注,预处理组对缺血组小鼠按照25μg/kg大鼠体重进行了右美托咪定预处理灌注。比较三组大鼠于再灌注24 h时的视网膜电图(ERG)、细胞凋亡指数(AI)、促凋亡因子(Bax)、抑凋亡因子(Bcl-2)表达水平、肿瘤坏死因子(TNF-α)及白细胞介素-6 (IL-6)表达水平。结果:健康组ERG显著优于缺血组,缺血组ERG显著优于预处理组,三组组间比较差异有统计学意义(F=1 296.98、667.99,P<0.05);健康组AI显著优于缺血组,缺血组AI显著优于预处理组,三组组间比较差异有统计学意义(F=43.32,P<0.05);三组大鼠Bax、Bcl-2、TNF-α、IL-6比较,差异有统计学意义(F=50.09、54.04、113.06、105.19,P<0.05)。结论:右美托咪定可能通过促进Bcl-2表达、抑制Bax表达以改善细胞凋亡指数,同时能够抑制TNF-α、IL-6表达,降低视网膜缺血再灌注损伤炎症效应,进而改善视网膜缺血再灌注损伤发挥保护作用。