神经妥乐平对H2O2致PC12细胞损伤的保护作用

目的 探索神经妥乐平对H2O2诱导的PC12细胞氧化应激损伤的影响及其潜在机制.方法 用CCK-8法检测细胞存活率,以流式细胞术检测细胞氧化损伤的发生、细胞内活性氧的生成及线粒体膜电位的变化,荧光显微镜观察细胞内活性氧的产生,qRT-PCR测定Caspase-3、Bax和Bcl-2 mRNA的表达.结果 PC12细胞存活率随H2O2浓度的增加而逐渐下降.其中,450μM H2O2处理细胞24 h后细胞存活率、凋亡率、坏死率明显降低;细胞内活性氧水平表达明显升高;线粒体膜电位JC-1红/绿荧光比值下降;Bax和Caspase-3的mRNA表达升高,而Bcl-2的mRNA表达下降,以上指标与对照组相比,差异有统计学意义(P＜0.05).而预先给予0.01UN/ml的NTP处理细胞12h可明显提高细胞存活率,降低细胞凋亡率和坏死率,减少细胞内活性氧生成并提高线粒体膜电位,抑制Bax和Caspase-3的mRNA表达,促进Bcl-2 mRNA的表达,以上指标与H2O2组相比,差异有统计学意义(P＜0.05).结论 NTP能抑制H2O2诱导的PC12细胞损伤,其神经细胞保护作用可能与其降低细胞内活性氧水平、维持线粒体膜电位的高能状态和抑制促凋亡基因表达、促进抗凋亡基因表达有关.     

辛伐他汀诱导K562细胞凋亡过程中对线粒体膜电位的影响

目的:观察辛伐他汀诱导人红白血病K562细胞凋亡时线粒体膜电位(Δψm)的变化及其与时间的关系。方法:常规培养细胞24h,辛伐他汀(20μmol.L-1)处理K562细胞12、24、48、72h,观测细胞形态学改变;MTT法检测细胞增殖抑制情况;流式细胞术检测细胞凋亡率和线粒体膜电位改变,并与溶剂对照组比较。结果:与对照组比较,辛伐他汀作用K562细胞48h后细胞出现核固缩、核碎裂和凋亡小体等形态学改变;作用12、24、48、72h后细胞凋亡率分别增加(2.55±0.35)%、(6.1±0.35)%、(14.15±0.42)%、(30.70±0.65)%,K562细胞凋亡率随着药物作用时间延长而增加;细胞膜电位降低百分率分别为(0.7±0.24)%、(39.6±4.80)%、(24.4±2.45)%、(6.0±1.62)%,24h时膜电位降低百分率最大。结论:线粒体跨膜电位降低是凋亡发生的早期事件,辛伐他汀诱导K562细胞凋亡的可能机制是通过使线粒体跨膜电位崩溃,从而导致细胞凋亡。     

en橙皮甙对H2O2诱导大鼠心肌细胞凋亡的影响

目的研究橙皮甙对H2O2诱导的大鼠心肌细胞凋亡的影响。方法培养并鉴定SD乳鼠心肌细胞;用H2O2诱导培养的大鼠心肌细胞凋亡,观察不同浓度橙皮甙（10^-8mmol/L、10^-5mmol/L、10^-3mmol/L）对SD乳鼠心肌细胞作用4、8、12h后,用Tunel法检测心肌细胞凋亡。结果橙皮甙组与模型组比较有抑制SD乳鼠心肌细胞凋亡的作用,且效应随橙皮甙浓度的增加和时间的延长而增强（P〈0.01）。结论橙皮甙对HO诱导的心肌细胞凋亡有抗凋亡保护心肌细胞的作用。     

二氮嗪对大鼠心肌线粒体膜电位及呼吸功能的影响

目的 :研究二氮嗪对大鼠心肌线粒体功能的影响 ,以探讨其心肌保护作用的可能机理。方法 :以罗丹明 12 3为荧光探针测定线粒体膜电位 ,氧电极法测线粒体呼吸 ,观察二氮嗪对正常大鼠心肌线粒体跨膜电位及呼吸的影响。结果 :5 0 μmol·L-1的二氮嗪可引起线粒体膜电位去极化 ,此影响可被钾通道阻滞剂消除 ;二氮嗪 10 0 μmol·L-1可降低大鼠心肌线粒体琥珀酸链的R3、R4速率 ,但不影响呼吸控制率。结论 :二氮嗪可调节大鼠心肌线粒体功能 ,这与其抗心肌缺血保护作用有关。     

颗粒细胞凋亡及线粒体膜电位与卵巢功能的相关性研究

目的探讨人卵巢黄素化颗粒细胞的凋亡率及线粒体膜电位的变化与卵巢功能及妊娠结局的相关性。方法应用流式细胞仪AnnexinV-PI双染法检测颗粒细胞凋亡,同时利用新型荧光探针JC-1测定细胞线粒体跨膜电位,分析其与卵巢功能的关系。结果黄素化颗粒细胞的凋亡率与年龄、基础FSH水平呈正相关（P〈0.01）,与获卵数,HCG日雌二醇水平及优质胚胎率呈负相关（P〈0.01）,颗粒细胞的凋亡率与Gn支数差异无统计学意义（P〉0.05）。妊娠组颗粒细胞的凋亡率低于未妊娠组（P〈0.05）。黄素化颗粒细胞线粒体膜电位与颗粒细胞凋亡率呈显著负相关（r=0.634,P〈0.01）,与优质胚胎率及妊娠率呈正相关关系（r=0.460,P〈0.05）。结论颗粒细胞的凋亡和线粒体膜电位可能影响卵巢功能及胚胎的体外发育潜能,从而影响妊娠结局。     

西红花酸对去甲肾上腺素所致原代培养心肌细胞能量代谢和凋亡的影响

目的研究西红花酸对去甲肾上腺素(NE)诱导原代培养心肌细胞能量代谢障碍和细胞凋亡的保护作用。方法1 μmol·L^-1 NE损伤原代培养的心肌细胞,检测细胞培养上清液的LDH、心肌细胞ATPase、线粒体琥珀酸脱氢酶(MSDH)的活力,线粒体膜电位的变化,流式细胞仪检测细胞凋亡,观察西红花酸保护作用。结果模型组细胞培养上清液LDH增加,心肌细胞MSDH和ATPase的活力降低,线粒体膜电位降低,心肌细胞凋亡率增加。西红花酸明显降低培养上清液LDH增加,提高MSDH和ATPase的活力、线粒体膜电位的水平,对心肌细胞的凋亡具有明显的保护作用。结论西红花酸对NE所致的心肌细胞能量代谢障碍和凋亡具有明显的保护作用。     

Bcl-2介导的芹菜素抗心肌细胞缺氧/复氧损伤作用

目的探讨芹菜素(apigenin,Api)在心肌细胞缺氧/复氧损伤中的作用,并阐明Api对心肌损伤的保护作用是否主要由Bcl-2介导。方法培养H9c2心肌样细胞;随机分为正常对照(Cont)组、缺氧/复氧(Anoxia/Reoxygenation,A/R)组、Api预处理组、Api+ABT-737组。MTT法检测细胞存活率;Western blot法检测Bcl-2表达;比色法检测培养液LDH活性、细胞SOD及GSH-Px活性、MDA含量;流式细胞仪检测心肌细胞ROS含量、线粒体膜电位及细胞凋亡。结果 Api预处理25 h后,心肌细胞Bcl-2表达呈剂量依赖性上调(P<0.01);细胞存活率升高,培养液LDH活性降低,细胞SOD、GSH-Px活性升高,MDA含量与ROS生成减少,线粒体膜电位更为稳定,细胞凋亡减少(P<0.01);Bcl-2抑制剂ABT-737则可取消Api的上述心肌保护作用。结论Api抗心肌A/R损伤作用涉及Bcl-2信号通路,至少部分依赖于其对Bcl-2表达水平的上调。     

橙皮甙在H2O2诱导的大鼠心肌细胞凋亡中的作用

目的研究橙皮甙对H2O2诱导的大鼠心肌细胞凋亡的影响。方法体外培养SD乳鼠心肌细胞,用H2O2诱导培养的大鼠心肌细胞凋亡,制造心肌细胞凋亡模型。设立对照组、模型组、溶媒组、橙皮甙低剂量组（终末浓度10^-5mmol／L）、中剂量组（终末浓度10^-5mmol／L）、高剂量组（终末浓度10^-5mmol／L）,于药物作用4、8、12h后用流式细胞仪检测细胞凋亡情况。结果橙皮甙组与模型纽比较有抑制SD乳鼠心肌细胞凋亡的作用,且效应随橙皮甙浓度的增加和时间的延长而增强（P〈0．01）。结论橙皮甙对H2O2诱导的心肌细胞凋亡有抗凋亡保护心肌细胞的作用。     

淫羊藿苷对异丙肾上腺素所致乳鼠心肌细胞损伤的保护作用

目的在异丙肾上腺素(isoproterenol,ISO)诱导原代培养乳鼠心肌细胞损伤的模型上,探讨淫羊藿苷对心肌细胞的保护作用。方法采用ISO损伤心肌细胞,通过MTT法检测心肌细胞存活率,以荧光染色激光共聚焦显微镜检测线粒体膜电位的变化,流式细胞仪检测细胞凋亡的发生。结果ISO处理心肌细胞72h后降低心肌细胞的存活率,诱导心肌细胞发生凋亡,凋亡率达35%,线粒体的膜电位明显降低。预先给予0.1～10μmol.L-1淫羊藿苷,可提高心肌细胞的存活率,改善线粒体的膜电位,降低心肌细胞的凋亡率。结论淫羊藿苷对ISO诱导原代培养心肌细胞损伤具有明显的保护作用。     

二氮嗪抑制Aβ1-42对U251细胞存活率、线粒体膜电位和细胞内活性氧的影响

目的：探讨线粒体膜上ATP敏感的钾离子通道开放药物二氮嗪防治Aβ1-42细胞毒性作用及其分子学机制。方法：采用不同浓度的Aβ1-42和二氮嗪同时处理神经胶质瘤U251细胞24h，以四唑盐比色法测定细胞存活率；四氯四乙基苯并咪唑基羰花青碘化物（JC-1）检测线粒体膜电位；     

Methylamine irisolidone,a novel compound,increases total ATPase activity and inhibits apoptosis in vivo and in vitro

We propose to further research the protective effect of MMI on myocardium ischemic rat model and H9c2 cells that underwent cell apoptosis induced by hypoxia. We established the myocardium ischemic rat model via the cardiac surgical procedures in vivo and treated the model rats with different concentration of MMI. In vitro, with the pretreatment of MMI for 12 h in the model of Na₂S₂O₄-induced hypoxia injury, the H9c2 cells viability was determined by MTT assay. We found that MMI had significantly improved cardiac function of the myocardial ischemia, and significantly decreased the reactive oxygen species level. The expression of P53, Bcl-2, Bax, and caspase-9 was also induced by MMI. In vitro study revealed a concentration-dependent increase in cell viability associated with MMI pretreatment. Annexin V-FITC and PI staining results showed that MMI had a preventive effect on hypoxia-induced apoptosis in H9c2 cells. MMI also inhibited the mitochondrial membrane potential decrease and increased total ATPase activity during hypoxia in H9c2 cells. In conclusion, MMI can enhance the cardiac function in myocardial ischemic rat and increase cell viability and attenuate the apoptosis in H9c2 cells induced by hypoxia, which was associated with inhibiting MMP decreasion and increasing total ATPase activity.     

23-羟基白桦酸诱导LoVo细胞凋亡与线粒体膜电位的变化

目的探讨23-羟基白桦酸对人结肠癌细胞株LoVo细胞增殖和凋亡的影响。方法采用MTT法检测23-羟基白桦酸对LoVo细胞的增殖抑制作用。Hoechst染色、流式细胞仪检测细胞凋亡及线粒体膜电位的变化。结果23-羟基白桦酸能抑制LoVo细胞的增殖,其作用呈明显的时间和剂量依赖性。Hoechst33258染色显示细胞凋亡特征。23-羟基白桦酸25、50、100及200μmol·L-1作用LoVo细胞48h后,其凋亡率分别为11.32%±0.92%、19.23%±0.78%、24.51%±5.88%及42.22%±2.32%,显示一定的剂量依赖性关系。与空白组相比,23-羟基白桦酸可明显降低LoVo细胞线粒体膜电位(P<0.01)。结论23-羟基白桦酸可抑制LoVo细胞的增殖,其机制与降低线粒体膜电位继而诱导LoVo细胞凋亡有关。     

葛根素保护双氧水诱导的SH-SY5Y细胞凋亡

目的探讨葛根素对双氧水(H_2O_2)诱导的SH-SY5Y细胞凋亡的保护作用及其机制。方法建立体外神经元损伤模型,MTT法观察细胞存活率;Hoechst 33342染色观察细胞核改变;JC-1染色检测细胞线粒体膜电位的改变;酶活性检测线粒体caspase-3和caspase-9的变化;Western blot检测细胞中Bcl-2、Bax、p-Akt、Akt蛋白的表达。结果与H_2O_2模型组相比,葛根素预处理能明显改善H_2O_2诱导的SHSY5Y细胞存活率下降(P<0.05),缓解H_2O_2引起的线粒体膜电位的下降(P<0.01),抑制caspase-3和caspase-9的酶活性(P<0.01),减少H_2O_2诱导的细胞凋亡。此外,葛根素还促进细胞内p-Akt、Bcl-2蛋白表达,抑制Bax蛋白表达,而这种作用能被PI3K/Akt的抑制剂LY294002所抑制。结论葛根素可保护H_2O_2诱导的SH-SY5Y细胞凋亡,这种保护作用可能是通过激活PI3K/Akt信号通路实现的。     

安宫牛黄丸通过诱导细胞凋亡和降低线粒体膜电位抑制肿瘤细胞增殖

目的 观察安宫牛黄丸的抗肿瘤作用,并探索其可能的作用机制。方法 安宫牛黄丸9,30,90,300和900 mg·L^-1分别与人胃癌MGC-803和人肝癌BEL-7402细胞孵育24,48和72 h。采用噻唑蓝(3-(4,5-二甲基噻唑-2-基)-5(3-羧基甲基苯基)-2-(4-磺酸苯基)-2H-四氮唑)细胞毒实验MTS法和克隆实验观察安宫牛黄丸对MGC-803和BEL-7402细胞增殖的影响;应用Hoechst 33258/PI染色和流式细胞仪检测细胞凋亡;荧光分光光度计检测线粒体膜电位。结果 安宫牛黄丸具有浓度依赖性地抑制肿瘤细胞增殖的作用。MTS法测定结果表明,安宫牛黄丸作用48和72 h对MGC-803细胞增殖具有抑制作用,浓度-效应相关系数分别为0.996(P=0.002)和0.756(P=0.024);与BEL-7402细胞作用48和72 h的浓度-效应相关系数分别为0.732(P=0.030)和0.702(P=0.037)。细胞克隆实验结果表明,安宫牛黄丸作用24 h可浓度依赖性地抑制MGC-803细胞(r=0.914,P=0.011)和BEL-7402细胞(r=0.871,P=0.024)克隆形成。Hoechst 33258/PI染色和流式细胞仪检测结果表明,安宫牛黄丸900 mg·L^-1作用24 h可诱导MGC-803和BEL-7402细胞凋亡,细胞凋亡百分率分别达27.2%和19.7%。安宫牛黄丸900 mg·L^-1作用后连续检测3 min,MGC-803和BEL-7402细胞的线粒体膜电位比对照组分别下降15.9%和15.0%。结论 安宫牛黄丸具有抑制肿瘤细胞增殖的作用,其作用机制与诱导细胞凋亡和降低肿瘤细胞线粒体膜电位有关。     

儿童手术应激后外周血中性粒细胞凋亡及线粒体膜电位变化

目的 探讨手术应激后儿童外周血中性粒细胞凋亡及线粒体膜电位变化.方法 择期手术患儿16例,分别于术前24h,术后24、72h采集外周血3.5～5ml.用梯度离心法分离出中性粒细胞培养15h.加入7-AAD、DioC6(3)染色.通过流式细胞仪检测细胞凋亡和线粒体膜电位.结果 术后24h中性粒细胞凋亡率明显减少[术前(13.27±7.11)%,术后(7.55±4.70)%,P＜0.05],术后72h仍处于减少状态[(5.47±2.67)%,P＜0.05].同时荧光指数也下降(术前46.08±29.19,术后30.72±15.84,P＜0.05).术后72h仍处于减少状态(29.63±22.39,P＜0.05).结论 手术创伤使外周血中性粒细胞凋亡减少,同时荧光指数降低,表明有较少的细胞线粒体膜电位降低.中性粒细胞凋亡的延迟是术后炎症反应综合征的原因之一.     

Effect on apoptosis、mitochondrial membrane potential and Ca~(2+) concentration in HepG-2 by CSEO

Objective To study on the mechanism of growth inhibiting and apoptosis inducing effect of total alkaloid in the CSEO(Capparis spinosa L.essential oil,CSEO)on human hepatocarcinoma cell Line HepG-2.Methods The growth inhibiting effect of the CSEO on human hepatocarcinoma cell Line HepG-2 was measured by MTT method.Morphological observation of the HepG-2 cells was completed by fluorescence microscope.The changing of mitochondrion membrane potential induced by CSEO was observed by staining with Rhodamine123.Effect of the CSEO on intracellular Ca2+ level of the HepG-2 cells was measured by laser confocal microscope.Results The CESO has obvious growth inhibiting effect on the HepG-2 and seems to be dose-dependent,and its IC50 is 127.5 μg·mL-1.The characteristic apoptosis morpha of HepG-2 cells has been observed,and the apoptosis percentage increase to 44.447% in the 300 μg·mL-1 dosage group.In addition,the progress of cells cycle of G1 period has been blocked,and the cellular proportion in S and G2 period is decreased in the 75 μg·mL-1 and 150 μg·mL-1 dosage groups by the function of CSEO for 48 h.The mitochondria membrane potential(Δψm)effected by CESO is decreased,while the curve moves toward left.In addition,the intracellular Ca2+ level is increased by the function of CESO in the middle and high dose groups.Conclusions The CESO has obviously growth inhibiting and apoptosis inducing effect on human hepatocarcinoma cell Line HepG-2 by the mechanism of decreasing the mitochondria membrane potential and increasing the intracellular Ca2+ level.     

Effects of UTP on membrane current and potential in rat aortic myocytes

The electrophysiological effects of UTP on freshly isolated rat aortic myocytes were examined using the perforated patch clamp technique. Application of ,β-methylene ATP (β-meATP) and UTP, putative P2X and P2Y₂ or P2Y₄ purinoceptor agonists, induced transient and oscillatory inward currents, respectively. Experiments with Cl⁻ channel blockers and different external Cl⁻ concentrations demonstrated that the oscillatory current elicited by UTP is attributable to activation of Cl⁻ channels. The transient component elicited by β-meATP appeared to be responsible for a non-selective cationic current. With internal application of low-molecular-weight heparin, a blocker of inositol 1,4,5-trisphosphate (InsP₃), the oscillatory current elicited by UTP was abolished. The oscillatory current was activated in an all-or-none manner by UTP over the concentration range 0.1 and 1 μM and the frequency and amplitude were independent of the UTP concentration. Under current-clamp mode, UTP produced an oscillatory membrane potential. These results show that rat aortic myocytes have at least two types of P2 receptors. Activation of the P2Y receptor by UTP produces InsP₃, which releases Ca²⁺ from the store site. The resulting increase in intracellular Ca²⁺ concentration causes the oscillatory Cl⁻ current and the subsequent membrane potential changes.     

Methotrexate induced mitochondrial injury and cytochrome c release in rat liver hepatocytes

Methotrexate (MTX) is a folic acid antagonist that is widely used to treat a variety of diseases. One of the most serious side effects of MTX therapy is hepatotoxicity. The potential molecular cytotoxic mechanisms of MTX toward isolated rat hepatocytes were investigated using Accelerated Cytotoxicity Mechanism Screening (ACMS) techniques. A concentration and time dependent increase in cytotoxicity and reactive oxygen species (ROS) formation and a decrease in mitochondrial membrane potential (MMP) were observed with MTX. Furthermore, a significant increase in MTX (300?μM)-induced cytotoxicity and ROS formation were observed when glutathione (GSH)-depleted hepatocytes were used whereas addition of N-acetylcysteine (a GSH precursor) decreased cytotoxicity. Catalase inactivation also increased MTX-induced cytotoxicity, while the direct addition of catalase to the hepatocytes decreased cytotoxicity. MTX treatment in isolated rat mitochondria caused swelling and significantly decreased adenosine triphosphate (ATP) and GSH content, and cytochrome c release. Potent antioxidants such as mesna, resveratrol and Trolox decreased MTX-induced cytotoxicity and ROS formation and increased MMP. This study suggests that MTX-induced cytotoxicity caused by ROS formation and GSH oxidation leads to oxidative stress and mitochondrial injury in rat hepatocytes.     

二苯乙烯苷对H_2O_2诱导的PC12细胞损伤的抗凋亡作用

目的:探讨二苯乙烯苷(2,3,5,4'-tetrahydroxystibene-2-O-β-D-glucoside,TSG)对H2O2诱导的PC12细胞损伤的抗凋亡作用。方法:本实验分为正常对照组、H2 O2处理组和H2 O2+TSG(0.1,1,10和50μmol.L-1)预处理组。采用MTT比色法和乳酸脱氢酶(LDH)测定法检测细胞活性,Hoechst染色观察细胞凋亡程度,Western Blotting检测细胞凋亡相关蛋白表达。结果:与正常对照组相比,细胞经H2O2诱导处理后,细胞存活率降低,LDH释放增加,Hoechst染色显示凋亡细胞增多,细胞核呈固缩突亮或碎块状致密浓染,Western Blotting显示促凋亡蛋白Bax表达升高,抑凋亡蛋白Bcl-2表达降低,Bcl-2与Bax的比值降低。不同浓度TSG预处理能改善H2O2所致的细胞存活率降低,减轻细胞凋亡程度,减少促凋亡蛋白Bax的表达以及增加抑凋亡蛋白Bcl-2的表达。结论:TSG可抑制H2O2诱导的PC12细胞损伤,其机制可能与抗凋亡有关。